May
16

Dispensing errors and ‘dispensing errors’

It just occurred to me that my posts on our recent paper discussing ‘dispensing errors’ could have been confusing for some clinicians or pharmacists for which ‘dispensing errors’ is totally altogether different..such as giving people the wrong drug which they have been prescribed.

Just thought I would clarify that up front. But things can get a bit fuzzy when pipettes are actually used to dispense/ give people drugs like in the example below. This goes to show the complexities of searching for a topic :

Drug Dev Ind Pharm. 2006 Feb;32(2):197-205.

Study of eye drops dispensing and dose variability by using plastic dropper tips.

Sklubalová Z, Zatloukal Z.

Source

Department of Pharmaceutical Technology, Charles University in Prague, Faculty of Pharmacy, Hradec Králové, Czech Republic. zdenka.sklubalova@faf.cuni.cz

Abstract

The application of eye drops from flexible dropper bottles fitted with different types of dropper tips is associated with the high variability of eye drop weights. The aim of this report was to investigate the simultaneous effect of three factors influencing the mean weight of drops dispensing from two plastic dropper tips. Using a designed experiment (Box-Behnken), the effect of the concentration of benzalkonium chloride solutions (BAC) in the range of 0-0.02%, the dispensing angle from 90 degrees to 30 degrees from horizontal, and the residual volume of liquid in the dropper bottle from 4 to 10 mL on the mean drop weights were examined. The significant effect of the increase in BAC concentration resulted in a linear decrease in drop weights for both of the dropper tips investigated. The significant effect of the dispensing angle was influenced by the dropper tip design. For the dropper tip A, the effect of the dropper tip tilt was described by the quadratic equation with a minimum, which corresponded to the dispensing angle equal to that of 48 degrees from horizontal. Below this angle, the increase in drop weights occurred due to the drop formation from the wetted external surface of the tip orifice. The linear decrease in drop weights in response to the decrease in dispensing angle was detected for the dropper tip B. The regression equations and the contour line plots obtained allowed the drop weights to be estimated for the actual combinations of both the BAC concentration and the dispensing angle. The effect of the residual volume was found to be non-significant. Based on the formula of Tate’s law, the direct proportion between surface tension of a solution and the radius of the effective perimeter of a dropper tip can be used to estimate the theoretical maximal weight of drops at the dispensing angle of 90 degrees . Using the stalagmometric values of surface tension of the BAC solutions, the maximal drop weights were estimated for both of the dropper tips investigated. A comparison between the theoretical and the experimentally measured drop weights enabled the dropper tips behavior to be discussed by using Harkins and Brown correction factor F. The F-value of 0.74 noted for the dropper tip A differed from that of stalagmometer F-value (0.61) indicating a deviation from the simple drop formation process in answer to more complicated design of the dropper tip A. On the other hand, the F-value of 0.6 observed for the dropper tip B demonstrated the better consistency with stalagmometry. As a result, the dropper tip B with the linear decrease of drop weights in response to the increased concentration of BAC and the decreased dispensing angle without the adverse external drop formation could be recommended in real drop dispensing.

PMID:

16537200

 

Prompted by the interest in the paper and feedback from different people I have been doing a bit of digging to find other papers that might be of interest..Pipetting errors get a few mentions in PubMed abstracts, some very unusual topics - but there is not a lot of detail to infer whether the papers are relevant.

 

Food Addit Contam Part A Chem Anal Control Expo Risk Assess. 2012;29(11):1770-9. doi: 10.1080/19440049.2012.712063. Epub 2012 Aug 29.

Evaluation of variability and quality control procedures for a receptor-binding assay for paralytic shellfish poisoning toxins.

Ruberu SR, Langlois GW, Masuda M, Perera SK.

Source

Drinking Water and Radiation Laboratory Branch and Environmental Management Branch, California Department of Public Health, 850 Marina Bay Parkway, Richmond, CA 94804, USA. Shiyamalie.Ruberu@cdph.ca.gov

Abstract

The receptor-binding assay (RBA) method for determining saxatoxin (STX) and its numerous analogues, which cause paralytic shellfish poisoning (PSP) in humans, was evaluated in a single laboratory study. Each step of the assay preparation procedure including the performance of the multi-detector TopCount® instrument was evaluated for its contribution to method variability. The overall inherent RBA variability was determined to be 17%. Variability within the 12 detectors was observed; however, there was no reproducible pattern in detector performance. This observed variability among detectors could be attributed to other factors, such as pipetting errors. In an attempt to reduce the number of plates rejected due to excessive variability in the method’s quality control parameters, a statistical approach was evaluated using either Grubbs’ test or the Student’s t-test for rejecting outliers in the measurement of triplicate wells. This approach improved the ratio of accepted versus rejected plates, saving cost and time for rerunning the assay. However, the potential reduction in accuracy and the lack of improvement in precision suggests caution when using this approach. The current study has recommended an alternate quality control procedure for accepting or rejecting plates in place of the criteria currently used in the published assay, or the alternative of outlier testing. The recommended procedure involves the development of control charts to monitor the critical parameters identified in the published method (QC sample, EC₅₀, slope of calibration curve), with the addition of a fourth critical parameter which is the top value (100% binding) of the calibration curve.

PMID:

22928711

 

Sex Transm Dis. 2012 Sep;39(9):733-4. doi: 10.1097/OLQ.0b013e318259efe2.

Mucus digestion improves the detection of Chlamydia trachomatis and Neisseria gonorrhoeae on the cobas 4800.

Miller A, Bromhead C, Jones M, Tustin P.

Source

From Aotea Pathology Ltd, Wellington, New Zealand.

Abstract

We compared the performance of cobas 4800 PCR for Neisseria gonorrhoeae with culture and found an association between pipetting errors and positive culture, caused by mucopurulent discharge. The problem may be resolved by pretreating samples with Sputasol, thus improving detection of both Chlamydia trachomatis and Neisseria gonorrhoeae.

PMID:

22902672

 

Rev Sci Instrum. 2010 Dec;81(12):124301. doi: 10.1063/1.3509395.

Absorbance and fluorometric sensing with capillary wells microplates.

Tan HY, Cheong BH, Neild A, Liew OW, Ng TW.

Source

Laboratory for Optics, Acoustics, and Mechanics, Department of Mechanical and Aerospace Engineering, Monash University, Clayton, Victoria 3800, Australia.

Abstract

Detection and readout from small volume assays in microplates are a challenge. The capillary wells microplate approach [Ng et al., Appl. Phys. Lett. 93, 174105 (2008)] offers strong advantages in small liquid volume management. An adapted design is described and shown here to be able to detect, in a nonimaging manner, fluorescence and absorbance assays minus the error often associated with meniscus forming at the air-liquid interface. The presence of bubbles in liquid samples residing in microplate wells can cause inaccuracies. Pipetting errors, if not adequately managed, can result in misleading data and wrong interpretations of assay results; particularly in the context of high throughput screening. We show that the adapted design is also able to detect for bubbles and pipetting errors during actual assay runs to ensure accuracy in screening.

PMID:

21198036

 

J Biomol Screen. 2010 Oct;15(9):1160-4. doi: 10.1177/1087057110381648. Epub 2010 Sep 17.

Capillary wells microplate with side optical access.

Tan HY, Ng TW, Neild A, Liew OW.

Source

Laboratory for Optics, Acoustics, & Mechanics, Department of Mechanical & Aerospace Engineering, Monash University, Clayton, Victoria, Australia.

Abstract

The presence of bubbles in liquid samples residing in microplate wells causes inaccuracies in fluorescence measurements. In addition, pipetting errors, if not adequately managed, can result in misleading data and wrong interpretations of assay results, particularly in the context of high-throughput screening. In this work, the authors describe an adapted design to the capillary wells microplate approach that permits side viewing. They demonstrate a prototype that detects bubbles and pipetting errors during actual assay runs to ensure accuracy in screening.

PMID:

20852025

 

I am also keen to see this recent paper :

J Lab Autom. 2013 Jan 25. [Epub ahead of print]

Evaluation of a Liquid Dispenser for Assay Development and Enzymology in 1536-Well Format.

Butendeich H, Pierret NM, Numao S.

Source

1Novartis Institutes for Biomedical Research, Basel, Switzerland.

Abstract

Although developments in liquid dispensers have made the use of 1536-well plates for high-throughput screening (HTS) standard, there is still a gap in dispenser technology for performing matrix experiments with several components. Experiments such as those performed during assay development and enzymological studies are therefore still performed by manual pipetting in lower-density plates. We have evaluated a new dispenser, the Certus liquid dispenser (Gyger Fluidics GmbH, Switzerland), that is capable of flexible dispensing in 1536-well format, with a dead volume of less than 200 µL. Taking advantage of the precision of the dispenser for volumes down to 50 nL, we have created concentration gradients on plates by dispensing different volumes of reagent and then backfilling with buffer. Using this method and the flexibility of the dispenser software, we have performed several multidimensional experiments varying two to three components, including an assay development for an HTS, a mode of inhibition study, and a cofactor optimization, in which we determined 32 K(M) values. Overall, the flexibility of the plate layout for multiple components, the accuracy to dispense volumes ranging 2 log orders, and minimal reagent usage enable this dispenser for complex biochemical experiments.

PMID:

23355542

 

..And also his one in which a 300,000 compound screen resulted in no hits. It makes me wonder whether the dispensing approach could have an impact on screens like this?

 

J Ocul Pharmacol Ther. 2013 Apr;29(3):298-309. doi: 10.1089/jop.2012.0135. Epub 2012 Oct 25.

In pursuit of synthetic modulators for the orphan retina-specific nuclear receptor NR2E3.

Qin Q, Knapinska A, Dobri N, Madoux F, Chase P, Hodder P, Petrukhin K.

Source

Department of Ophthalmology, Columbia University Medical Center, New York, NY 10032, USA.

Abstract

PURPOSE:

NR2E3 is an orphan nuclear receptor expressed exclusively in photoreceptor cells of the retina. NR2E3-specific modulators may prolong photoreceptor survival in patients with dry age-related macular degeneration and other forms of retinal degeneration. To definitively establish NR2E3 as a photoreceptor protection target, identification of small-molecule NR2E3 modulators and their testing in animal models of retinal degeneration are required. Development of the high-throughput screen (HTS)-compatible screen for small-molecule NR2E3 modulators is the first step toward this goal.

METHODS:

Purification protocol for isolation of the functionally competent soluble NR2E3 protein after its expression in the insect Sf9 cells was developed. The time-resolved fluorescence energy-transfer (TR-FRET) assay assessing agonist-sensitive interaction between apo-NR2E3 and transcriptional corepressor RetCOR was used for characterization of the previously reported putative NR2E3 agonist, Compound 11a, and to conduct the HTS for novel small-molecule NR2E3 modulators (direct and inverse agonists). A counterscreen TR-FRET assay that measures the affect of test compounds on PPARγ interaction with corepressor NCOR was used for assessing the specificity of compounds identified in the HTS.

RESULTS:

We developed the cell-free TR-FRET assay for small-molecule NR2E3 modulators, which is based on agonist-induced disruption of the interaction between GST-tagged apo-NR2E3 and MBP-tagged fragment of transcriptional corepressor RetCOR. Compound 11a, a putative NR2E3 agonist, did not affect the NR2E3-RetCOR interaction, as was established by its titration in the developed assay. The assay was miniaturized for an ultralow-volume 1,536-well format and automated into 3 simple pipetting steps. Consistent with excellent assay performance, the test runs established a Z’-score within the 0.6-0.8 range. Analysis of the mid-size National Institutes of Health collection of 315,001 structurally diverse drug-like compounds confirmed excellent assay performance, but did not reveal NR2E3-specific agonists or inverse agonists.

CONCLUSIONS:

A robust and reliable TR-FRET assay for small-molecule NR2E3-specific modulators suitable for the analysis of million compound-strong HTS libraries was developed. A previously described putative NR2E3 agonist, Compound 11a, is unlikely to represent a direct NR2E3 agonist. Application of the developed assay for screening of a more abundant and diverse compound collection be required for identification of synthetic NR2E3 ligands.

PMID:

23098562

[PubMed - in process]

PMCID:

PMC3613967

Free PMC Article

 

Well if anyone reading this has any papers on dispensing errors that I might be interested in – as opposed to those documenting “giving the wrong doses of drugs to patients” – please let me know and add them to the comments below. My guess is I will be digging for a good long while at this rate.

 

May
14

Designed obsolescence and drug resistance: are they really that different?

My recent ‘bad luck’ with iPhones, iPad and a Sony Vaio laptop had me thinking about obsolescence, so much so that I fell asleep trying to remember the very word. What about pharmaceuticals, are they designed to become obsolete? Are we living in a world in which the things we rely on ultimitately become obsolete at an alarming rate?

Over the past year I had an iPad 2 that needed complete replacement in 6 months as it failed to charge. A nearly 2 year old iPhone 4 replaced first due to failure of the video sound / speaker phone, then that in turn was replaced in about 4 months due to failed headphone jack. The months old Sony Vaio has travelled to Texas 4 times since November to have the hard disk replaced each time, ultimately to be exchanged for another laptop. To me this failure of technology is alarming, but is it planned? Perhaps gone are the days when a device you had made a significant investment in would last for many years. A laptop usually lasts me 2 years before it starts to have some issue (fan, power cord, battery etc). My first printer lasted me over 5 years, since then I am replacing them every 2 years, creating singlehandedly a mountain of used IT related hardware. I depend on these tools to do my work.

This had me thinking about what else we depend on in life and can we tolerate obsolescence. I was naturally thinking about drugs which are much more important than my IT hardware needs. Sure there are drugs that have been around for over 100 years like Aspirin , quinine, digoxin, paracetamol etc and they are still in wide use today. But there are also diseases which become resistant to drugs e.g. isoniazid resistance and Tuberculosis, artemisinin resistance and malaria due to genetic mutations or the efflux of drugs out of the bacteria or parasite, respectively. There are also examples of other drug resistance/ diseases like melarsoprol resistance and Human African Trypanosomiasis and Candida species resistance to antibiotics (as well as combinations of antibiotics). Drug resistance also is well known in cancers and there is a role in other diseases like epilepsy,  HIV, hepatitis, schizophrenia and beyond. Sure I am mixing up the obvious here, human tolerance to drugs and viruses that mutate to resist the drug/s which have very different mechanisms.  However beyond the thousands of examples of papers on drug resistance there appears to be relatively little written on obsolescence and drugs in general. Diseases are certainly complex and drugs are relatively simple in comparison. But I am not aware that anyone has really analyzed why some drugs can still be useful after 100 omore years and others can be obsolete within a few years of release. Are we unwittingly designing-in obsolescence into new drugs, do we need to think about how we can make them more stable in the face of mutations in their targets in the same way we can design in ’resistance’/ stability to metabolism and efflux? Is this even possible?

Designing longevity in drugs perhaps flies in the face of rational business decisions because of the short patent lifetime (and yet Bayer still holds onto Aspirin) and the ultimate move to generic drugs, in which case the innovator has to come up with a new molecule for the disease in question or leave home empty handed. Which begs the question, has our system of innovation, patents, Hatch-Waxman Act driven the pharmaceutical companies to designed obsolescence, because there is no long term financial benefit of a drug that has a 100 year lifetime for them anymore? Repositioning or repurposing old drugs for new uses certainly could help a drug remain in use and relevant and thus avoiding obsolescence. I think a lifetime analysis of drugs would be interesting or has this already been done?

A world in which we have to replace drugs for a major disease / infection/ virus every 2 years would be intolerable if not a public health disaster. And yet there is certainly concern that we are seeing increasing levels of drug resistance. Perhaps its time for a rethink about how we discover, target and ultimately design drugs to have a long life so that we can prosper.

 

 

 

May
13

A virtuous cycle

Since publishing a couple of papers in PLOS ONE (here and here) over the past few weeks and my respective blogs (here, here, here and here) there seems to be more interest than usual on this blog and much of this has been driven by attention from Derek Lowe’s In the Pipeline blog.

I have summarized this all in the following graphic. I wonder if this represents a virtuous circle that self reinforces interest in the open access articles or this blog? I am not sure which because I only have data from my side of the equation. Also a big component is likely the press that the dispensing paper received. I am totally at a loss as to where this will lead or what it really means. Will It be possible to find another topic that can achieve so much interest? What I do know is that I have tried to be as balanced/ restrained as possible in presenting what has happened over the past several months. I am pretty sure I am not the only person this stuff happens to when submitting papers and I am pretty sure it happens everywhere. The question is how do we improve publishing in science? I am not sure I can answer that in a single blog, but other people should be able to learn from my experiences at least.

May
13

Rare diseases make it into Chemical and Engineering News – chemists can help !

I want to take some time to highlight a terrific 4 part article  “Orphans find a home” that came out today in Chemical and Engineering News by Lisa Jarvis which I think absolutely captures what I have been seeing the last few years through my interactions with several rare and ultra rare disease groups – or fighter mums as they term themselves. In full disclosure I do get a mention in the article (on the online version which has a Resaerch Kick-starter feature) as does Jill Wood, Lori Sames and Allison Moore whose foundations Jonahs Just Begun, Hannah’s Hope Fund and Hereditary Neuropathy Foundation , respectively are highlighted and with whom I volunteer in my “spare” time.

I met with Lisa at the Science Online meeting and discussed over lunch what had happened over the last few years and my interactions with Jill, Lori and Allison and how they are really making amazing strides. Lisa has put a lot of time into the article interviewing the different parent advocates, families, scientists, pharma executives, FDA regulators as well as doing research on ultra rare diseases such as the 13 mucopolysaccharidosis diseases. The article is remarkable because it is in a predominantly Chemistry focussed magazine. YES it is important that chemists see this type of article and I will tell you why.

As the article explains I met Jill in late 2011 at a 1 to 1 meeting at Partnering for Cures and was amazed at what she had gone through and done in a small space of time. I hope the tens of thousands of readers of this magazine/ website will see the same. Parents like the many highlighted in the article are driving the search for treatments and we “chemists” can help them. There are likely many readers that will be inspired by reading the article, if they want to find out how they can help please get in contact with any rare disease foundation they see, like those described in the article too. Perhaps others with an entrepreneural streak or who have recently lost their jobs will feel that rare diseases are a ray of hope on the pharma / drug discovery landscape. Maybe they will have an idea and develop a molecule or treatment, maybe they will help raise visibility for rare diseases, or maybe they or a loved one has a rare disease and they did not know it until reading this…While big Pharma is certainly showing more interest in rare diseases, most of the treatments have come from biotechs to date that in some cases are being sought out by the bigger fish,  but do they have the ability to move as fast as smaller biotechs? VC are also investing in rare disease start ups. I see this as just the tip of the iceberg. Chemists have to be a part of the future of rare disease research and I think Lisa’s article could catalyze this.

If readers of the article have any suggestions on what we could do to engage more chemists I would be interested and if I can connect you to rare disease foundations I would be happy to do this.

 

 

May
09

My experiences with publishing at PLOS

I should begin by saying I really want to support the concept of open access. I read lots of papers that are open access, in particular in PLOS, BMC journals etc..I want to do everything I can to get people to be more open and make research accessible, I even encourage scientists to put their data in such journals on Figshare, slideshare etc… However I am currently conflicted and this comes from several recent experiences over the past year. I should also say that in the interests of full disclosure I am currently on the editorial board of Pharmaceutical Research (Springer), Drug Discovery Today (Elsevier), Mutation Research Reviews (Elsevier) and Chem-Bio Informatics (CBI-Society).

It seems that over the last year just getting collaborative papers published (for me) has become an incredibly difficult task as documented here on this blog. For example getting the work on the Green solvents mobile app published took close to a year. The “Disruption paper” at Science reviewed but rejected  and then tried TIPS, was reviewed and acceptable but they rejected as we had a preprint at Nature Precedings also took close to a year. Both of these examples ended up in traditional closed access journals. Finally there was the recent “dispensing paper” that went through Science and Analytical Chemistry (twice rejected in each case) before finding a home at PLOS ONE, which also took close to a year (but not PLOS fault).

I have one more example, this did not take as long but for me it documents how a good paper can be held back for no aparent reason. On October 26th 2012 we submitted a paper ‘Enhancing Hit Identification in Mycobacterium tuberculosis Drug Discovery Using Validated Dual-Event Bayesian Models’ to PLOS Computational Biology, which seemed appropriate considering we used Bayesian Machine learning models to predict prospectively potential compounds with activity and then tested hundreds of molecules and found >20% hit rate. we felt the choice of journal was appropriate given the computational nature and that such work on this scale had not previously been published. We had a companion paper “Dual-event machine learning models to accelerate drug discovery” (which would eventually be published as “Bayesian models leveraging bioactivity and cytotoxicity information for drug discovery”) using additional TB Bayesian models which combined retrospective and prospective evaluation as well as in vivo work, which we sent to Chemistry & Biology. This journal is a part of the Cell Press family of journals owned by Elsevier, so a closed journal compared to PLOS which is an open access publisher. What follows is our experience with PLOS.

We did not have to wait long for a response:

Dear Dr. Ekins,

Thank you very much for submitting your manuscript ‘Enhancing Hit Identification in Mycobacterium tuberculosis Drug Discovery Using Validated Dual-Event Bayesian Models’ for review by PLOS Computational Biology. I apologize for the delay in handling your manuscript. We have held a consultation among the editors. Unfortunately the general opinion was that while the problem is important and the results are useful, we do not feel that the manuscript is suitable for PLOS Computational Biology.

The main strength of the manuscript is in the validated database that it provides. The method (software) is not provided as an open source as we require, and it is also unclear to what extent it is novel rather than incremental to what was published earlier. As such we believe that it would fit better into a drug, or medicinal chemistry journal.

We are sorry that we cannot be more positive on this occasion, but we hope that you appreciate the reasons for this decision and that you will consider PLOS Computational Biology for other submissions in the future.

While we cannot consider your manuscript for publication in PLOS Computational Biology, we very much appreciate your wish to present your work in an Open Access publication. We therefore want to alert you to an alternative that you may find attractive. Our sister journal PLOS ONE (www.plosone.org) is a swift, high-volume, efficient and economical system for the publication of peer-reviewed research in all areas of science and medicine; a unique publishing forum that exploits the full potential of the web to make the most of every piece of research.

If you would like to submit your work to PLOS ONE we can transfer your files directly into PLOS ONE’s manuscript handling system; please contact the PLOS ONE publication staff (transfers@editorialoffice.co.uk) now, citing your manuscript tracking number. If you would like more information about submitting to PLOS ONE please either visit its website or email plosone@plos.org.

Thank you again for your support of PLOS Computational Biology and open-access publishing.

Sincerely,

Ruth  Nussinov
Editor-in-Chief
PLOS Computational Biology

So PLOS Computational Biology prevents people from publishing using commercial software to do drug discovery, how lame is that. What next banning Microsoft Word? We even provided the models created to anyone that wants them and have already shared them with several pharmas. We took their advice and by Nov 6th the manuscript was in PLOS ONE for review. We did not expect the following on Dec 14th

PONE-D-12-34738
Enhancing Hit Identification in Mycobacterium tuberculosis Drug Discovery Using Validated Dual-Event Bayesian Models
PLOS ONE

Dear Dr. Ekins,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we have decided that your manuscript does not meet our criteria for publication and must therefore be rejected.

Two independent reviewer reports were fully in contrast (see below). Therefore, I asked to a third reviewer, who has found major limitations and problems with the study in the current status. Specifically, this reviewer cannot help but notice a somewhat disturbing lack of completeness in this report. The authors constantly refer to a submitted but not published (as far as the reviewer could tell) manuscript (ref. 30, Ekins S, Reynolds R, Kim H, Koo M-S, Ekonomidis M, et al. (2012) Dual-event machine learning models to accelerate drug discovery. Submitted.), in which the Bayesian procedure applied here should be reported in full details together with a retrospective validation and a preliminary  prospective application. Without ref. 30 published – or, at the very least, confidentially available to reviewers – a fair assessment of the scientific quality of the results presented here, is impossible.  And, also in this case, it would remain to be established how big and general an improvement the results presented here would make with respect to those presented in ref. 30.

I am sorry that we cannot be more positive on this occasion, but hope that you appreciate the reasons for this decision.

Yours sincerely,

Andrea Cavalli, PhD
Academic Editor
PLOS ONE

Reviewers’ comments:

Reviewer #1: The manuscript entitled “Enhancing Hit Identification in Mycobacterium tuberculosis Drug Discovery Using Validated Dual-Event Bayesian Models” by Ekins et al. describes an series of three prospective validation experiments using commercially available molecules from Asinex, Maybridge  and Selleck Chemicals kinase libraries. In the process of this evaluation, the authors have identified valuable starting points for the discovery of novel antitubercular agents: 124 actives against Mycobacterium tuberculosis, including two families built around drug-like heterocyclic cores and several FDA-approved human kinase-targeting drugs.

1. The research article describes a method that provides hits more efficiently, thus decreasing the time and cost involved in their evolution to leads and eventually a clinical candidate. The methodological approach well sounds.
2. The results reported in the manuscript have not been published elsewhere.
3. The in vitro antitubercular experiments of the selected molecules have been conducted rigorously with appropriate controls, although without replication. The cross-validation of the best models reveals a good predictive capability, substantiating their robustness. Methods and reagents have been described in sufficient detail.
4. The data presented in the manuscript support the conclusions drawn and the results appear exhaustively discussed.
5. The article is presented in an intelligible fashion and is written in standard English.
6. The research meets all applicable standards for the ethics of experimentation and research integrity.
7. The article adheres to appropriate reporting guidelines and community standards for data availability.

For these reasons, I recommend the publication of the manuscript on PlosOne without alteration.

Reviewer #2: The authors state that they have generated a “Bayesian model with enhanced predictive capability” but at the moment the cited paper (30) is only submitted. In this paper, they are validating again a model not published yet and unavailable for the readers/reviewers. In my opinion the acceptance of this paper has to follow the publication of paper cited in 30.
In addition, while I have no reason to question the results described in this manuscript, the discussion has to be written in a more intelligible way. On the other hand, I am not convinced that the paper has significant novelty to justify publication in PONE. I recommend publication in a more specialized journal.
Moreover, authors have to check more carefully the references before submission, i.e. in references 9, 18, 29, 32, 33 some details are missing.

I had to request the following review because it was omitted from the email

Reviewer#3
The manuscript submitted by Ekins and colleagues describes the application of a Bayesian classifier aimed at selecting molecules displaying inhibitory activity toward Mtb. The screening procedure carried out on three libraries of commercially available compounds returned an average hit rate of 22.5%.

Despite a certain tendency toward overselling a little bit the described results, this hit rate would be quite interesting. Yet, I cannot help but notice a somewhat disturbing lack of completeness in this report. The authors constantly refer to a submitted but not published (as far as I could tell) manuscript (ref. 30, Ekins S, Reynolds R, Kim H, Koo M-S, Ekonomidis M, et al. (2012) Dual-event machine learning models to accelerate drug discovery. Submitted.) in which the Bayesian procedure applied here should be reported in full details together with a retrospective validation and a preliminary  prospective application. Without ref.30 published – or, at the very least, confidentially available to this reviewer – a fair assessment of the scientific quality of the results presented here, is impossible.

And, also in this case, it would remain to be established how big and general an improvement the results presented here would make with respect to those presented in ref. 30.
It is my opinion that, in the present form, relying too heavily on unpublished data, the manuscript should be rejected for publication on Plos ONE but maybe it could be addressed to a more specific and technical forum shifting the focus more on the hits rather thatn on the procedure that generated them.

This opinion is solely based on my scientific expertise and it is not biased by any competing interest.

So our paper was rejected because we referenced our other paper which was submitted at roughly the same time and did not provide this at the same time even though the content of both manuscripts is different. Dec 15th Chemistry & Biology sent us a manuscript asking for major revisions to this paper..Which we did and it was accepted Jan 3rd. In the meantime…

Anyway I sent the following

Sent: 15/12/2012
To: plosone@plos.org
Subject: Re: PLOS ONE Decision: PONE-D-12-34738

Dear Dr Cavalli,
I am happy to send ref 30, which deals with a totally seperate test set. I had no idea that was required along with submission of this paper. Our previous papers on single event Bayesian models using retrospective and prospective validation have all been published.

I thought PLOS was meant to focus on the science …novelty was not an issue?

Sincerely
Sean Ekins

On the 18th Dec 2012 I recieved the following:

Dear Dr. Ekins,

Thank you for contacting PLOS ONE.

I am writing to inquire whether you would be interested in formally appealing the original decision rendered through PLOS ONE regarding the manuscript PONE-D-12-34738.  While I cannot guarantee that your appeal will be approved by our in house editors, they will consider appeals via the formal appeals process when you submit a detailed rebuttal letter.

Appeal requests should be made in writing, not by telephone, and should be addressed to plosone@plos.org with the word “appeal” in the subject line.  Authors should provide detailed reasons for the appeal and point-by-point ‘responses to the reviewers’ and/or Academic Editor’s comments.  Decisions on appeals are final without exception.

If you have any further questions or concerns, please do not hesitate to contact us.

Kind regards,

Dianne Cartwright
Staff EO
PLOS ONE

Case Number: 01546111
ref:_00DU0Ifis._500U069JTc:ref

So Dec 20th we submitted both manuscripts to PLOS ONE with our appeal listed below.

Dear PLOS ONE,

We are writing to formally appeal the original decision for PONE-D-12-34738. After reading the reviews sent to us, it became clear that the basis of rejection was questionable and did not hinge on failures in any of the seven criteria listed as publication criteria (http://www.plosone.org/static/publication).

  1. The study presents the results of primary scientific research.
  2. Results reported have not been published elsewhere.
  3. Experiments, statistics, and other analyses are performed to a high technical standard and are described in sufficient detail.
  4. Conclusions are presented in an appropriate fashion and are supported by the data.
  5. The article is presented in an intelligible fashion and is written in standard English.
  6. The research meets all applicable standards for the ethics of experimentation and research integrity.
  7. The article adheres to appropriate reporting guidelines and community standards for data availability.

It should be noted that our manuscript (30) is currently under revision at Chemistry and Biology and is enclosed with this appeal. We now include a rebuttal of all 3 reviews now in our possession.

Rebuttal

Letter from Editor

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we have decided that your manuscript does not meet our criteria for publication and must therefore be rejected.

Two independent reviewer reports were fully in contrast (see below). Therefore, I asked to a third reviewer, who has found major limitations and problems with the study in the current status. Specifically, this reviewer cannot help but notice a somewhat disturbing lack of completeness in this report. The authors constantly refer to a submitted but not published (as far as the reviewer could tell) manuscript (ref. 30, Ekins S, Reynolds R, Kim H, Koo M-S, Ekonomidis M, et al. (2012) Dual-event machine learning models to accelerate drug discovery. Submitted.), in which the Bayesian procedure applied here should be reported in full details together with a retrospective validation and a preliminary prospective application. Without ref. 30 published – or, at the very least, confidentially available to reviewers – a fair assessment of the scientific quality of the results presented here, is impossible. And, also in this case, it would remain to be established how big and general an improvement the results presented here would make with respect to those presented in ref. 30.

 I am sorry that we cannot be more positive on this occasion, but hope that you appreciate the reasons for this decision.

Yours sincerely,

Andrea Cavalli, PhD
Academic Editor
PLOS ONE

Response : The editor suggests reviewer #3 as the reason for their decision as follows “Specifically, this reviewer cannot help but notice a somewhat disturbing lack of completeness in this report.” After reading the comments from reviewer #3 below it would appear that this would refer to the manuscript referenced as (30) being submitted elsewhere. In the manuscript, we clearly stated reference 30 was submitted. At any time during the editing or review process we would have been happy to supply reference 30 and it is enclosed with this appeal.  We have previously published papers outlining the validation of single-event Bayesian models, which are more appropriate for comparison to the dual-event Bayesian models described in this current work. We contend that the current manuscript stands alone and, therefore, a fair assessment of the scientific quality of the results is possible and does not require reference 30. For example, references 20, 21, and 22 could be used for comparison. However, as stated previously, had we been notified at any point during the review process prior to the decision being rendered, we would have supplied the manuscript under review.

Reviewers’ comments:

Reviewer #1: The manuscript entitled “Enhancing Hit Identification in Mycobacterium tuberculosis Drug Discovery Using Validated Dual-Event Bayesian Models” by Ekins et al. describes an series of three prospective validation experiments using commercially available molecules from Asinex, Maybridge and Selleck Chemicals kinase libraries. In the process of this evaluation, the authors have identified valuable starting points for the discovery of novel antitubercular agents: 124 actives against Mycobacterium tuberculosis, including two families built around drug-like heterocyclic cores and several FDA-approved human kinase-targeting drugs.

1. The research article describes a method that provides hits more efficiently, thus decreasing the time and cost involved in their evolution to leads and eventually a clinical candidate. The methodological approach well sounds.
2. The results reported in the manuscript have not been published elsewhere.
3. The in vitro antitubercular experiments of the selected molecules have been conducted rigorously with appropriate controls, although without replication. The cross-validation of the best models reveals a good predictive capability, substantiating their robustness. Methods and reagents have been described in sufficient detail.
4. The data presented in the manuscript support the conclusions drawn and the results appear exhaustively discussed.
5. The article is presented in an intelligible fashion and is written in standard English.
6. The research meets all applicable standards for the ethics of experimentation and research integrity. 7. The article adheres to appropriate reporting guidelines and community standards for data availability.

For these reasons, I recommend the publication of the manuscript on PlosOne without alteration.

RESPONSE: We thank the reviewer for their comments which supports publication based on the 7 criteria for publication listed above.

Reviewer #2:

Comment #1: The authors state that they have generated a “Bayesian model with enhanced predictive capability” but at the moment the cited paper (30) is only submitted. In this paper, they are validating again a model not published yet and unavailable for the readers/reviewers. In my opinion the acceptance of this paper has to follow the publication of paper cited in 30.

RESPONSE: We thank the reviewer for their comments. To clarify, the models used in this study are fully described in this manuscript and supporting information. These models are available upon request as described in the supporting information. However, it should be clear we are not validating this work against reference 30, they are distinct manuscripts that are independent. This current manuscript can stand alone. We have demonstrated in this manuscript that we can expand the concept of dual-event Bayesian models across many datasets, using the models to select compounds without human intervention. In this study, we have tested 550 molecules and identified 124 actives. Paper 30 is currently with the editors of Chemistry and Biology after we addressed changes they requested. We have provided the manuscript with this rebuttal. In it we provide one small example of the use of a dual-event Bayesian model to test 7 compounds and identify 5 hits. So the manuscripts are clearly distinct in scope with this manuscript probing the antitubercular efficacy of nearly 80X more molecules.

Comment #2: In addition, while I have no reason to question the results described in this manuscript, the discussion has to be written in a more intelligible way. On the other hand, I am not convinced that the paper has significant novelty to justify publication in PONE. I recommend publication in a more specialized journal.

RESPONSE: We thank the reviewer for their comments. Based on the PLOSONE 7 criteria for publication, novelty is not listed as one of them. We would disagree that our manuscript is not novel when, in fact, we have clearly performed the largest prospective testing of any computational models for TB drug discovery. Our manuscript details testing of 550 molecules and identification of 124 actives.  We have written this manuscript to appeal to a broad readership and have attempted to make it generally accessible.

Comment #3: Moreover, authors have to check more carefully the references before submission, i.e. in references 9, 18, 29, 32, 33 some details are missing.

RESPONSE: At the time of writing full reference information for references 9, 18, 29, 33 were unavailable as these were in press – ref 18 is still in press. The full reference for reference 32 is correct as provided.

9. Stanley SA, Grant SS, Kawate T, Iwase N, Shimizu M, et al. (2012) Identification of Novel Inhibitors of M. tuberculosis Growth Using Whole Cell Based High-Throughput Screening. ACS Chem Biol 7: 1377-1384.

29. Singh N, Chaudhury S, Liu R, Abdulhameed MD, Tawa G, et al. (2012) QSAR Classification Model for Antibacterial Compounds and Its Use in Virtual Screening. J Chem Inf Model 52: 2559-2569.

33. Ballester PJ, Mangold M, Howard NI, Robinson RL, Abell C, et al. (2012) Hierarchical virtual screening for the discovery of new molecular scaffolds in antibacterial hit identification. J R Soc Interface 9: 3196-3207.

Reviewer #3:

Comment #1: The manuscript submitted by Ekins and colleagues describes the application of a Bayesian classifier aimed at selecting molecules displaying inhibitory activity toward Mtb. The screening procedure carried out on three libraries of commercially available compounds returned an average hit rate of 22.5%.
Despite a certain tendency toward overselling a little bit the described results, this hit rate would be quite interesting. Yet, I cannot help but notice a somewhat disturbing lack of completeness in this report. The authors constantly refer to a submitted but not published (as far as I could tell) manuscript (ref. 30, Ekins S, Reynolds R, Kim H, Koo M-S, Ekonomidis M, et al. (2012) Dual-event machine learning models to accelerate drug discovery. Submitted.) in which the Bayesian procedure applied here should be reported in full details together with a retrospective validation and a preliminary prospective application. Without ref.30 published – or, at the very least, confidentially available to this reviewer – a fair assessment of the scientific quality of the results presented here, is impossible.

RESPONSE: We thank the reviewer for their comments. We do not believe we have made any efforts to oversell the research and would appreciate more specific examples so we can address them. Paper 30 is currently with the editors of Chemistry and Biology after we addressed changes they requested. We have provided the manuscript with this rebuttal and the full methods for Bayesian model development are included in both manuscripts (as well as those previously published by us on single-event models -references 20, 21, and 22). Please note that the current manuscript also has unique models for a dataset resulting from screening Mtb against a human kinase compound library not described in reference 30.  In reference 30, we provide one small example of the use of a dual-event Bayesian model to test 7 compounds and identify 5 hits. The remainder of reference 30 focuses on prospective evaluation of single-event Bayesian models. We have demonstrated in the current manuscript that we can expand the concept of dual-event Bayesian models across many datasets, using the models to select compounds without human intervention. In this study, we have tested 550 molecules and identified 124 actives.

We would also assert that the scientific quality of the results in the current manuscript are independent of reference 30.

Comment #2: And, also in this case, it would remain to be established how big and general an improvement the results presented here would make with respect to those presented in ref. 30.
It is my opinion that, in the present form, relying too heavily on unpublished data, the manuscript should be rejected for publication on Plos ONE but maybe it could be addressed to a more specific and technical forum shifting the focus more on the hits rather thatn on the procedure that generated them.

RESPONSE: As we reference on page 10, “Previous work highlighted a 14% hit rate when applying a single-event Bayesian model and a dual-event model afforded 5/7 hits with an MIC ≤ 2 mg/ml [1]. “ In contrast, in the current study we assayed a total of 550 molecules in vitro (compared with the 7 in reference 30), and identified 124 actives (compared with 5 in reference 30). The current study is therefore more useful as an example to compare to traditional HTS as well as previous single-event models that were validated retrospectively (references 20, 21, and 22). The current study greatly expands on the efforts in reference 30. We are not aware of any other published TB computational studies that have made such extensive prospective predictions using machine learning models followed up by in vitro screening for validation.

We are not relying on unpublished data in paper 30; the data for each paper are distinct and independent. This current manuscript can stand alone. We have demonstrated in this manuscript that we can expand the concept of dual-activity Bayesian models across many datasets, using the models to select compounds without human intervention.

We recognize that other scientists (readers of PLOSONE) who would otherwise perform HTS should understand that prior HTS data can be readily used with commercially available and increasingly open software (Gupta et al., Drug Metab Dispos. 2010 Nov;38(11):2083-90) to build models that can be used to dramatically narrow the number of compounds that need to be tested to find active compounds. By publishing in a more technical journal, we would miss the very scientists we are trying to reach as an audience in PLOSONE. We have gone into detail on some of the hits in this manuscript and are in the process of following them up for further optimization.

Comment #3: This opinion is solely based on my scientific expertise and it is not biased by any competing interest.

RESPONSE: We thank the reviewer for that statement.

We conclude that the manuscript was not rejected based on the 7 publication criteria. We asserted in the manuscript as submitted (and described above) how this study differed from that disclosed in reference 30 which was under review elsewhere at the same time and that the current study is independent of it. We were not requested to submit the manuscript 30 to PLOSONE at any time during the editorial or review process. If omission of reference 30 was so critical, surely reviewer # 1 would have raised the issue too. Instead, they noted that we complied with the seven criteria for publication. It appears there were no other comments of note from reviewers #2 and #3 that require addressing. We have dealt with the minor updates in references that were in press (or their information was not available in PubMed) during submission of the manuscript.

We hope that this manuscript is now acceptable and we trust that PLOSONE will overturn the initial decision which we feel was made hastily without any recourse for us to provide additional information.

                        Yours sincerely,

 …….

After not getting responses to several follow up emails ( there are no phone numbers that get you through to any editors at PLOS) Jan 24th 2013 we received the following.

Dear Dr. Ekins,

Please accept our apologies for not replying sooner. Unfortunately we had a technical issue with our inbox, we do apologise for this technical error. I can confirm that all five of your emails have now been reinstated and we are dealing with this as a matter of urgency.

Your request for appeal has been forwarded to our internal editors who will determine whether or not PLOS ONE will consider your appeal. We may also need to consult additional editorial board members.

We will notify you via email once a decision has been made on whether we will consider your appeal.  If your request for an appeal is granted, your manuscript will go out for review a second time and may incur additional review time.  Please be aware that appeals typically take longer to review than new submissions due to the complexity of their history. Decisions on appeals are final without exception. Details about appeals can be found under “Editorial and Peer-Review Process” at: http://www.plosone.org/static/information.action.

We will be in touch again soon with more information, but in the meantime, please do not hesitate to contact us if you have any further questions or concerns.

Thank you and best wishes,

Dianne Cartwright
Staff EO
PLOS ONE

Case Number: 01546111
ref:_00DU0Ifis._500U069JTc:ref

Then Jan 31 we get the following request.

PONE-D-12-34738
Enhancing Hit Identification in Mycobacterium tuberculosis Drug Discovery Using Validated Dual-Event Bayesian Models
PLOS ONE

Dear Dr. Ekins,

Thank you for your email regarding the above manuscript, I apologise for not replying sooner.

I understand from your last email that the submission to Chemistry & Biology is now in press. In the light of this, I agree that it is not necessary to include a full description of the Bayesian models in the current manuscript.

I would be grateful if you could please revise the manuscript to update the citations to the publication in Chemistry & Biology and provide a brief description of how the current study relates to the work in that publication and resubmit your manuscript files online. While I appreciate that you note that two papers are different in scope, I believe it will still be relevant for the further evaluation of the work -and eventually for readers if the manuscript is accepted – to have a some details regarding the relationship between the two studies outlined in the current manuscript.

Once we receive the resubmitted files, the manuscript will be re-evaluated as per the appeal process, we will aim to reach a decision without further external review, but please note that the re-evaluation will be handled by Academic Editors and thus the steps involved will depend on their consideration.

I hope this is of help but please do let me know if you have any further queries.

With best wishes,

Iratxe Puebla
Consulting Editor, PLOS ONE

After several  enquires Feb 24th we recieve the following.

PONE-D-12-34738R1
Enhancing Hit Identification in Mycobacterium tuberculosis Drug Discovery Using Validated Dual-Event Bayesian Models
PLOS ONE

Dear Dr. Ekins,

I am writing to update you on the status of your appeal submission to the PLOS ONE journal. 

Currently, your manuscript is being discussed by two editorial board members.  We have been in communication with these individuals, and we are doing all we can to ensure that your paper will receive a timely and proper decision.

Many thanks for your patience, and as always, please feel free to email us any further questions or concerns that may arise.

Regards,

Kate Massingham
PLOS ONE

Then Feb 27th the following

Dear Dr. Ekins,

I have been contacted by the Academic Editor handling your recent submission PONE-D-12-34738 requesting a copy of your article currently in press at Chemistry & Biology, Bayesian Models Leveraging Bioactivity and Cytotoxicity Information for Drug Discovery. Would you please send me a copy of this article to forward to the Academic Editor to facilitate his review?

 
Please let me know if you have any questions regarding this request.


Kind regards,
Tara

PLOS I OPEN FOR DISCOVERY
Tara Garnett I Publications Assistant

 

So after Joel resend the files while I was out of the country I responded on the 6th March.

Dear Tara,

I am following up on your last email as Joel was able to send the paper requested last week (which we had already submitted on 2 seperate occasions). Has any decision been made yet please.

Also please note this case has involved emails to Dianne Cartwright and this appeal was submitted on the 20th of Dec 2012, it is now March 6. I think if we do not have a response in the next week we will take this elsewhere.

Sincerely
Sean

A quick response on the 7th March..

PONE-D-12-34738R1
Enhancing Hit Identification in Mycobacterium tuberculosis Drug Discovery Using Validated Dual-Event Bayesian Models
PLOS ONE

Dear Dr. Ekins,

Thank you for your email which has been forwarded to me.  Currently, your manuscript is being discussed by two editorial board members.  We are in constant communication with these individuals, and we are doing all we can to ensure that your paper will receive a timely and proper decision.

Many thanks for your patience, and as always, please feel free to email us any further questions or concerns that may arise.

Best regards,
Kate Massingham
PLOS ONE

Finally March 14th we get a decision…but wait it went out for review all over again!!!

CC: daniel.sem@cuw.edu
PONE-D-12-34738R1 Enhancing Hit Identification in Mycobacterium tuberculosis Drug Discovery Using Validated Dual-Event Bayesian Models PLOS ONE
Dear Dr. Ekins,
We have carefully reviewed your manuscript, and also sent it out for external review. We note that the previous concern regarding reference #30 has now been addressed, since you have provided access to that manuscript. Furthermore, the reviewer was in favor of publishing with modification, and we are in agreement.
Please address the reviewer concerns, and also provide an update on the citation for the manuscript cited as reference 30, as appropriate.
We encourage you to submit your revision within forty-five days of the date of this decision.
When your files are ready, please submit your revision by logging on to http://pone.edmgr.com/ and following the Submissions Needing Revision link. Do not submit a revised manuscript as a new submission. Before uploading, you should proofread your manuscript very closely for mistakes and grammatical errors. Should your manuscript be accepted for publication, you may not have another chance to make corrections as we do not offer pre-publication proofs.
If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter.
Please also include a rebuttal letter that responds to each point brought up by the academic editor and reviewer(s). This letter should be uploaded as a Response to Reviewers file.
In addition, please provide a marked-up copy of the changes made from the previous article file as a Manuscript with Tracked Changes file. This can be done using ‘track changes’ in programs such as MS Word and/or highlighting any changes in the new document.
If you choose not to submit a revision, please notify us.
Yours sincerely,
Daniel Sem, PhD Associate Professor of Pharmaceutical Sciences Concordia University Wisconsin Academic Editor PLOS ONE
Yung-fu Chang, DVM, Ph.D Professor of Molecular Microbiology, College of Veterinary Medicine, Cornell University  Academic Editor PLOS ONE
 

Reviewers’ comments:

Reviewer’s Responses to Questions
Comments to the Author
1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass this form and submit your “Accept” recommendation.

Reviewer #1: (No Response)


Please explain (optional).
Reviewer #1: This is an interesting article by Ekins et al. showing how they can used a dual-event Bayesian model to identify Mtb actives in commercially available compound libraries.
Overall, their results are interesting and the TB community will benefit from sharing this information.  In addition, there will be widespread interest to apply such Bayesian methodologies to drug discovery for other pathogens. 
Issues to address:
1) This article erroneously compares hit rates using Bayesian methodology and single point HTS.  As they state, single point HTS is often performed at ~10 and 25 uM.  However, this article defines a “hit” as one that shows a MIC of 90% growth inhbition at 100 uM using re-ordered compounds (page 9, 4 lines from bottom, “where a hit demonstrated >90% inhibition at 100 ug/mL”).  The mistake in logic is that hit rates do not increase in a linear manner as one changes the cutoff threshold, as the authors imply, but instead they can be closer to exponential.  This is also observed when one decreases the % inhibition cut-off from, let’s say, 90% to 20%.  The 90% cutoff is standard, but also arbitrary for large screens and it is very common for both academic and big pharma groups to analyze data well below 90% inhibition.  Thus, if someone using standard HTS has a 1% hit rate at 10 uM, they may have a 25% hit rate if they screen at 100 uM (it could also be lower — a lot depends on the library).  The reason most academic and industrial labs screen at 10 to 25 uM is that they usually aim for a hit rate of 0.5-1%, which limits the number of compounds to re-confirm in cherry picking assays.  There is a big difference between designing an HTS and cut-off rates to obtain a 1% hit rate, and claiming that an HTS hit rate of 1% (as a fixed value).
The authors should compare apples to apples.  I’d recommend that they describe their hit rate using an MIC of 10 or 25 uM as a cutoff in a manner similar to a normal single-point HTS.  Since their data was determined in MIC format, they have the data (the MIC must have been tested at 100, 50, 25, 12.5, 6 ? uM).  What is their hit rate at 10 uM?  At 25 uM?  Most of the MIC’s for compounds shown in this article fall in the 50-100 uM category and most likely their hit rate will be very low if using 10 uM as an MIC cutoff.  This could be summarized in a table in which the authors could present hit rates for 100 uM and also 10 uM; this will allow readers to draw their own conclusions.
Taking account such higher hit rates of “regular” HTS may impact other figures in the paper, for example supplementary Figure S9.
2)  Even if the author’s hit rate decreases significantly after performing the analysis suggested in point 1, obviously their Bayesian predictive methodology still has immense value in TB drug discovery.  However, the authors would be better served re-writing this article to tone down the overselling of their results, tone down their negative perception of standard screening methods (which, for all their listed negatives, still work), and consider presenting their work in a different context – Bayesian virtual screening of libraries is a complementary technique to standard methods.  Bayesian virtual screening may pick up weak actives missed by standard HTS, and pick up interesting pharmacophores (often weak hits) that could be developed to generate improved activity with medicinal chemistry.  Ironically, they also have to take into account that their Bayesian learning method uses data generated by standard HTS.
Finally, although their method is obviously very rapid, they still have to reorder compounds and test them in standard assays.  Many pharmaceutical companies have technologies to screen upwards of 100K compounds in whole cells screens per day – including Mtb (with a 1-2 day wait for reading plates).
3) The LORA assay is well accepted and appreciated in the TB field.  However, the Bayesian models were generated using publically available data for Mtb grown at 20% O2, not data from a low-oxygen screen.  Perhaps the authors may want to clarify in the text why they chose to test compounds by LORA as well – or at least point out that their model should not be relevant to the LORA data (my understanding is that it should not be predictive of LORA activity since the model was based on replicating activity at 20% O2).
4)  Was there a quality control for the identity and purity of each chemical re-ordered?  I did not see that in the methods.  Were there solubility issues observed at the higher concentrations that gave MIC values?
5)  Were MICs/LORA assays performed once?  In triplicates?  How did control compounds perform in the assays?  Please comment and/or update Methods.
6)  Please included calculated selectivity index (SI) for each compound in tables; one SI for MABA, one SI for LORA – this will make data much easier to go through (this is common for this type of data).
7)  A minor point – the technical jargon used is highly specific for Bayesian analysis and will be lost on many readers.  I found some information in the Methods.  The article may be easier to understand, and thus be more accessible to readers from other fields, if the authors spell out terms and give brief explanations of their meaning/significance.  For example, “LOO ROC”, pg7, etc.


2. Is the manuscript technically sound, and do the data support the conclusions?
The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Partly


Please explain (optional).
Reviewer #1: This article erroneously compares hit rates using Bayesian methodology and single point HTS.  As they state, single point HTS is often performed at ~10 and 25 uM.  However, this article defines a “hit” as one that shows a MIC of 90% growth inhbition at 100 uM using re-ordered compounds (page 9, 4 lines from bottom, “where a hit demonstrated >90% inhibition at 100 ug/mL”).  The mistake in logic is that hit rates do not increase in a linear manner as one changes the cutoff threshold, as the authors imply, but instead they can be closer to exponential.  This is also observed when one decreases the % inhibition cut-off from, let’s say, 90% to 20%.  The 90% cutoff is standard, but also arbitrary for large screens and it is very common for both academic and big pharma groups to analyze data well below 90% inhibition.  Thus, if someone using standard HTS has a 1% hit rate at 10 uM, they may have a 25% hit rate if they screen at 100 uM (it could also be lower — a lot depends on the library).  The reason most academic and industrial labs screen at 10 to 25 uM is that they usually aim for a hit rate of 0.5-1%, which limits the number of compounds to re-confirm in cherry picking assays.  There is a big difference between designing an HTS and cut-off rates to obtain a 1% hit rate, and claiming that an HTS hit rate of 1% (as a fixed value).
The authors should compare apples to apples.  I’d recommend that they describe their hit rate using an MIC of 10 or 25 uM as a cutoff in a manner similar to a normal single-point HTS.  Since their data was determined in MIC format, they have the data (the MIC must have been tested at 100, 50, 25, 12.5, 6 ? uM).  What is their hit rate at 10 uM?  At 25 uM?  Most of the MIC’s for compounds shown in this article fall in the 50-100 uM category and most likely their hit rate will be very low if using 10 uM as an MIC cutoff.  This could be summarized in a table in which the authors could present hit rates for 100 uM and also 10 uM; this will allow readers to draw their own conclusions.
Taking account such higher hit rates of “regular” HTS may impact other figures in the paper, for example supplementary Figure S9.


3. Has the statistical analysis been performed appropriately and rigorously?
Reviewer #1: No


Please explain (optional).
Reviewer #1: Please refer to comment above regarding hit rates and request for authors to determine their hit rate using Bayesian analysis at 10 and 25 uM vs 100 uM.


4. Does the manuscript adhere to standards in this field for data availability?
Authors must follow field-specific standards for data deposition in publicly available resources and should include accession numbers in the manuscript when relevant. The manuscript should explain what steps have been taken to make data available, particularly in cases where the data cannot be publicly deposited.

Reviewer #1: Yes


Please explain (optional).
Reviewer #1: (No Response)


5. Is the manuscript presented in an intelligible fashion and written in standard English?
PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors below.

Reviewer #1: Yes


6. Additional Comments to the Author (optional)
Please offer any additional comments here, including concerns about dual publication or research or publication ethics.

Reviewer #1: There is concern regarding a second article (reference 30) that is in publication elsewhere, it appears that it may be very similar to the current publication.


7. If you would like your identity to be revealed to the authors, please include your name here (optional).
Your name and review will not be published with the manuscript.

Reviewer #1: (No Response)

So we resubmitted AGAIN!! March 2oth

Reviewer’s Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass this form and submit your “Accept” recommendation.

Reviewer #1: (No Response)
Please explain (optional).

Reviewer #1: This is an interesting article by Ekins et al. showing how they can used a dual-event Bayesian model to identify Mtb actives in commercially available compound libraries.

RESPONSE: Thank you.


Overall, their results are interesting and the TB community will benefit from sharing this information. In addition, there will be widespread interest to apply such Bayesian methodologies to drug discovery for other pathogens.

RESPONSE: Thank you.



Issues to address:

1) This article erroneously compares hit rates using Bayesian methodology and single point HTS. As they state, single point HTS is often performed at ~10 and 25 uM. However, this article defines a “hit” as one that shows a MIC of 90% growth inhbition at 100 uM using re-ordered compounds (page 9, 4 lines from bottom, “where a hit demonstrated >90% inhibition at 100 ug/mL”). The mistake in logic is that hit rates do not increase in a linear manner as one changes the cutoff threshold, as the authors imply, but instead they can be closer to exponential. This is also observed when one decreases the % inhibition cut-off from, let’s say, 90% to 20%. The 90% cutoff is standard, but also arbitrary for large screens and it is very common for both academic and big pharma groups to analyze data well below 90% inhibition. Thus, if someone using standard HTS has a 1% hit rate at 10 uM, they may have a 25% hit rate if they screen at 100 uM (it could also be lower — a lot depends on the library). The reason most academic and industrial labs screen at 10 to 25 uM is that they usually aim for a hit rate of 0.5-1%, which limits the number of compounds to re-confirm in cherry picking assays. There is a big difference between designing an HTS and cut-off rates to obtain a 1% hit rate, and claiming that an HTS hit rate of 1% (as a fixed value).

The authors should compare apples to apples. I’d recommend that they describe their hit rate using an MIC of 10 or 25 uM as a cutoff in a manner similar to a normal single-point HTS. Since their data was determined in MIC format, they have the data (the MIC must have been tested at 100, 50, 25, 12.5, 6 ? uM). What is their hit rate at 10 uM? At 25 uM? Most of the MIC’s for compounds shown in this article fall in the 50-100 uM category and most likely their hit rate will be very low if using 10 uM as an MIC cutoff. This could be summarized in a table in which the authors could present hit rates for 100 uM and also 10 uM; this will allow readers to draw their own conclusions.

Taking account such higher hit rates of “regular” HTS may impact other figures in the paper, for example supplementary Figure S9.

 

RESPONSE: Thank you for this suggestion. To be clear we do not perform a direct comparison between single point and MIC hit rates, the reviewer would appear to be conflating text from different parts of the manuscript. We do not state or imply anywhere in the manuscript that hit rates increase in a linear manner as one changes the cutoff threshold. As described in the paper molecules were tested from the Asinex Library, and the Maybridge Library at a single concentration of 100 mg/mL. The kinase library was screened at 50 mg/mL. In all three cases we looked at compounds that resulted in greater than or equal to 90% inhibition of Mtb activity. We only have MIC data for MABA and LORA for the selected hits so the proposed suggested approach of using MIC of 10 or 25 uM for all compounds does not appear relevant or possible based on the data we have produced for this paper. In fact, the process of single point screening followed by MIC testing of hits is routine. In addition we show in Table S5 for comparison hit rates at the Institute for Tuberculosis Research for libraries of 1000 to 100,000 molecules performed at 10-50uM for which there appears to be no relationship in hit rate and concentration. It is likely that this hit rate will be influenced by diversity of the libraries as well rather than any concentration used for screening. We are also no aware of others looking at hit rates at different concentrations.

                                                                                                                                             

2) Even if the author’s hit rate decreases significantly after performing the analysis suggested in point 1, obviously their Bayesian predictive methodology still has immense value in TB drug discovery. However, the authors would be better served re-writing this article to tone down the overselling of their results, tone down their negative perception of standard screening methods (which, for all their listed negatives, still work), and consider presenting their work in a different context – Bayesian virtual screening of libraries is a complementary technique to standard methods. Bayesian virtual screening may pick up weak actives missed by standard HTS, and pick up interesting pharmacophores (often weak hits) that could be developed to generate improved activity with medicinal chemistry. Ironically, they also have to take into account that their Bayesian learning method uses data generated by standard HTS.

Finally, although their method is obviously very rapid, they still have to reorder compounds and test them in standard assays. Many pharmaceutical companies have technologies to screen upwards of 100K compounds in whole cells screens per day – including Mtb (with a 1-2 day wait for reading plates).

 

RESPONSE: We agree that Bayesian methods will be important for tuberculosis research as we have demonstrated in this manuscript and previous papers since 2010. However this manuscript is novel because it presents a truly prospective and large scale analysis of predictions unlike any of our previous studies or those from other groups. Contrary to the reviewers suggestion the hit rate calculated is in line with previous calculations generated across different libraries in our hands. We do not believe that we have ‘oversold’ the results, we are presenting the data in a transparent manner across this paper and ref 30. We are quite open about some Bayesian models not performing well in some cases as described in the results and in the discussion e.g. see bottom of page 14. We are also continuing the development of the models we started with in 2010. So this study represents the evolution of these in terms of refining the data including cytotoxicity. The reality is that no other groups are doing prospective computational prediction and testing for Mtb activity. Also while the technique is complimentary to HTS we are saying that there is enough HTS screening data now for TB that we can start with Bayesian models and pick through vendor libraries and compounds that have received little attention. Instead of screening every compound we could feasibly pick less than 1% and test it. It should also be clear that the data we are using is coming from HTS screens of the various collaborators, so this opinion expressed in the manuscript is coming from screeners and modelers. Neither of the previous two reviewers had any issues with the manner in which the data was presented or how the manuscript written.

Our approach is indeed rapid and reordering, supply and testing of compounds can all be achieved in 1-2 weeks. Finally, as further evidence of the value of these models, we suggest screening 100k compounds is unnecessary and have provided the models in the manuscript to two pharmaceutical companies so they can cherry pick thousands of compounds from upwards of 500K-1M compound plus libraries.



3) The LORA assay is well accepted and appreciated in the TB field. However, the Bayesian models were generated using publically available data for Mtb grown at 20% O2, not data from a low-oxygen screen. Perhaps the authors may want to clarify in the text why they chose to test compounds by LORA as well – or at least point out that their model should not be relevant to the LORA data (my understanding is that it should not be predictive of LORA activity since the model was based on replicating activity at 20% O2).

RESPONSE: LORA and MABA MIC data was only generated on hit compounds, we were not predicting LORA activity. The LORA assay was used to see if any of the hits from single point screening were also active in this assay at low oxygen concentrations.

4) Was there a quality control for the identity and purity of each chemical re-ordered? I did not see that in the methods. Were there solubility issues observed at the higher concentrations that gave MIC values?

RESPONSE: These compounds were used as is which is frequently the case in such studies.  It would be prohibitively expensive to QC such a high number of compounds and the samples are supplied within claimed QC ranges by the commercial supplier.  Furthermore, several of the libraries were supplied in very small amounts that would make it difficult to run a thorough QC.  We have published numerous papers in reputable journals based on initial HTS screening data of commercial samples without additional verification of the supplied sample and quality.  It is routine to run and report these types of studies on small library samples and publish the data based on the claimed QC by the company.  Any follow up work would typically require purchasing or preparing enough material to confirm sample structure, quality, and activity in the screens. A statement has been added to the paper regarding the fact that compounds were used as supplied from the commercial company.  No overt solubility issues were identified or the samples would have been eliminated from the screens or a lower dose used.

5) Were MICs/LORA assays performed once? In triplicates? How did control compounds perform in the assays? Please comment and/or update Methods.

RESPONSE: LORA MIC data, was only run once with 8 concentrations and is in line with standard protocols used by this laboratory for many other libraries and studies.

6) Please included calculated selectivity index (SI) for each compound in tables; one SI for MABA, one SI for LORA – this will make data much easier to go through (this is common for this type of data).

RESPONSE: Thank you for pointing this out. We have now added the SI and additional text to tables S2-S4..

7) A minor point – the technical jargon used is highly specific for Bayesian analysis and will be lost on many readers. I found some information in the Methods. The article may be easier to understand, and thus be more accessible to readers from other fields, if the authors spell out terms and give brief explanations of their meaning/significance. For example, “LOO ROC”, pg7, etc.

RESPONSE Thank you for this suggestion. Leave-one-out cross-validation receiver operator curve (LOO ROC) has been added in results section, it was also defined in the methods section previously. It appears that this is the only definition that needed amending.
2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Partly


Please explain (optional).

Reviewer #1: This article erroneously compares hit rates using Bayesian methodology and single point HTS. As they state, single point HTS is often performed at ~10 and 25 uM. However, this article defines a “hit” as one that shows a MIC of 90% growth inhbition at 100 uM using re-ordered compounds (page 9, 4 lines from bottom, “where a hit demonstrated >90% inhibition at 100 ug/mL”). The mistake in logic is that hit rates do not increase in a linear manner as one changes the cutoff threshold, as the authors imply, but instead they can be closer to exponential. This is also observed when one decreases the % inhibition cut-off from, let’s say, 90% to 20%. The 90% cutoff is standard, but also arbitrary for large screens and it is very common for both academic and big pharma groups to analyze data well below 90% inhibition. Thus, if someone using standard HTS has a 1% hit rate at 10 uM, they may have a 25% hit rate if they screen at 100 uM (it could also be lower — a lot depends on the library). The reason most academic and industrial labs screen at 10 to 25 uM is that they usually aim for a hit rate of 0.5-1%, which limits the number of compounds to re-confirm in cherry picking assays. There is a big difference between designing an HTS and cut-off rates to obtain a 1% hit rate, and claiming that an HTS hit rate of 1% (as a fixed value).

The authors should compare apples to apples. I’d recommend that they describe their hit rate using an MIC of 10 or 25 uM as a cutoff in a manner similar to a normal single-point HTS. Since their data was determined in MIC format, they have the data (the MIC must have been tested at 100, 50, 25, 12.5, 6 ? uM). What is their hit rate at 10 uM? At 25 uM? Most of the MIC’s for compounds shown in this article fall in the 50-100 uM category and most likely their hit rate will be very low if using 10 uM as an MIC cutoff. This could be summarized in a table in which the authors could present hit rates for 100 uM and also 10 uM; this will allow readers to draw their own conclusions.

Taking account such higher hit rates of “regular” HTS may impact other figures in the paper, for example supplementary Figure S9.

 

RESPONSE: As described previously above in 1-

Thank you for this suggestion. To be clear we do not perform a direct comparison between single point and MIC hit rates, the reviewer would appear to be conflating text from different parts of the manuscript. We do not state or imply anywhere in the manuscript that hit rates increase in a linear manner as one changes the cutoff threshold. As described in the paper molecules were tested from the Asinex Library, and the Maybridge Library at a single concentration of 100 mg/mL. The kinase library was screened at 50 mg/mL. In all three cases we looked at compounds that resulted in greater than or equal to 90% inhibition of Mtb activity. We only have MIC data for MABA and LORA for the selected hits so the proposed suggested approach of using MIC of 10 or 25 uM for all compounds does not appear relevant or possible based on the data we have produced for this paper. In fact, the process of single point screening followed by MIC testing of hits is routine. In addition we show in Table S5 for comparison hit rates at the Institute for Tuberculosis Research for libraries of 1000 to 100,000 molecules performed at 10-50uM for which there appears to be no relationship in hit rate and concentration. It is likely that this hit rate will be influenced by diversity of the libraries as well rather than any concentration used for screening. We are also no aware of others looking at hit rates at different concentrations.

 3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: No


Please explain (optional).

Reviewer #1: Please refer to comment above regarding hit rates and request for authors to determine their hit rate using Bayesian analysis at 10 and 25 uM vs 100 uM.

RESPONSE: As described previously above in 1-

Thank you for this suggestion. To be clear we do not perform a direct comparison between single point and MIC hit rates, the reviewer would appear to be conflating text from different parts of the manuscript. We do not state or imply anywhere in the manuscript that hit rates increase in a linear manner as one changes the cutoff threshold. As described in the paper molecules were tested from the Asinex Library, and the Maybridge Library at a single concentration of 100 mg/mL. The kinase library was screened at 50 mg/mL. In all three cases we looked at compounds that resulted in greater than or equal to 90% inhibition of Mtb activity. We only have MIC data for MABA and LORA for the selected hits so the proposed suggested approach of using MIC of 10 or 25 uM for all compounds does not appear relevant or possible based on the data we have produced for this paper. In fact, the process of single point screening followed by MIC testing of hits is routine. In addition we show in Table S5 for comparison hit rates at the Institute for Tuberculosis Research for libraries of 1000 to 100,000 molecules performed at 10-50uM for which there appears to be no relationship in hit rate and concentration. It is likely that this hit rate will be influenced by diversity of the libraries as well rather than any concentration used for screening. We are also no aware of others looking at hit rates at different concentrations.
4. Does the manuscript adhere to standards in this field for data availability?

Authors must follow field-specific standards for data deposition in publicly available resources and should include accession numbers in the manuscript when relevant. The manuscript should explain what steps have been taken to make data available, particularly in cases where the data cannot be publicly deposited.

Reviewer #1: Yes
Please explain (optional).

Reviewer #1: (No Response)
5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors below.

Reviewer #1: Yes
6. Additional Comments to the Author (optional)

Please offer any additional comments here, including concerns about dual publication or research or publication ethics.

Reviewer #1: There is concern regarding a second article (reference 30) that is in publication elsewhere, it appears that it may be very similar to the current publication.

RESPONSE: This paper is different to ref 30 (which is due to be published in the next week) and has been provided to the editors of PLOSONE previously– this is the whole reason for this re-review. We have previously extensively documented how the two are unique.
7. If you would like your identity to be revealed to the authors, please include your name here (optional).

Your name and review will not be published with the manuscript.

Reviewer #1: (No Response)

RESPONSE: Thank you for reviewing it.

But they had made it more difficult in the interim by changing editorial Manager..March 21

Dear Sean,

Thank you for contacting PLOS ONE.

We apologize for the difficulty you experienced while attempting to resubmit your manuscript.  We have recently updated the Editorial Manager system to require co-author zip codes. This means that authors of revisions that previously included sufficient co-author details in their original submission will be presented with an error message when they try to submit their manuscript. Please go back to the details page and fill in the zip code for each co-author before you attempt to submit your manuscript again.

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Jackie Surplice
EO Staff
PLOS ONE

Case Number: 01878752
ref:_00DU0Ifis._500U07B37m:ref

After several more emails on formating and the addition of our other paper now published..April 3rd

PONE-D-12-34738R2
Enhancing Hit Identification in Mycobacterium tuberculosis Drug Discovery Using Validated Dual-Event Bayesian Models
PLOS ONE

Dear Dr. Ekins,

I am pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE.

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PLOS ONE

I will spare you all the emails back and forth on production around heading levels, figure resolutions etc..But needless to say we probably dealt with most people at PLOS. One point of contact would have been ideal. Dianne Cartwright is acknowledged for giving us the opportunity to appeal and Daniel Sem for the addition to his editing workload. But honestly based on our responses it would have been faster to submit the paper elsewhere and get it published. The paper came out May 7th. The Chemistry & Biology paper came out March 21.

I have published in PLOS Computational Biology previously and by comparison had relatively good experience for this one, while a more recent paper literally had to be cut in half  and part provided as a supplemental file before acceptance, which seem incredible for an online journal. Combined with our previous experience of PLOS ONE editorial overstretching to demanding paper press release edits it pains me to say this but I am on the lookout for alternative journals. Perhaps PeerJ, possibly F1000 research. I try to do interesting work with collaborators, push the boundries a little. I am persistant and will keep fighting for papers and ideas I believe in, but at some stage you have to move on. So I have come up with 5 points that I would like to see in a journal.

1. Common sense

2. Responsivenes

3. Accountability

4. Cost effectiveness

5. Transparency

 

May
07

Molecule names but no structures again on NCATS

One has to ask how often history repeats itself. In the case of NCATS its at least every year.

Last year a few of us brought to light the case of the drug company (industry) provided compounds looking for a repurposing home on the NCATS website, which oddly enough did not have any structures.  This provided fodder for several blogs here, here, here and  lead to a paper and our own efforts to find the structures with Chris Southan and Antony Williams described here.

Now today I see a tweet

NCATS@ncats_nih_gov20h

NCATS wants you! Pharma and biotech partners are needed to further develop and commercialize NCATS technologies: http://1.usa.gov/13cKzGv

and I respond

Sean Ekins@collabchem2h

@ncats_nih_gov will be interesting to see if you get nibbles, most assume pharma wants later stage cpds – partner with disease foundations?

Then Chris Southan responds

Christopher Southan@cdsouthan1h

@collabchem @ncats_nih_gov  see http://cdsouthan.blogspot.se/2013/05/ncats-vice-versa-cpds-more-blinded.html …

It would appear that again NCATS are listing compound IDs without structures..so again its left for scientists to do the grunt work to figure out the correct molecule structure and ID match. This is absolutely nuts. Here we are funding NCATS out of our taxes and they are fishing for pharmas to partner their molecules and not even providing structures. Will they ever learn?

Perhaps if they provided structures of the molecules it might help them partner the molecules and rare and neglected disease groups might even be interested..still sticking with my tweet, pharmas likely to be more interested in later stage compounds..This feels like the movie GroundHog day.

 

 

 

May
06

Why does this issue still give me nightmares?

A week or so ago I was seriously contemplating giving up blogging after just a so-so level of interest over 2 years and a couple of spikes that really only corresponded to issues around database quality which is not even the main focus of of my research. My blog is by far not the most important thing in my life but I was asking myself why I do it. Then one mention of a recent paper  on Derek Lowe’s “In the Pipeline” has ignited some interest in what I have written around the paper and gone to show that the blog can add something the paper cannot, a human factor, a sense of the frustration that goes into the scientific process. Ironically I have written about reviews on another paper in the past and had far less interest. I do not even think this paper is the most important thing I have ever done (e.g. I like this )– that is open for debate, but it has certainly been the cause for many sleepless nights (the night the paper appeared, last night etc. being pretty notable). Why you might ask?

Well lets begin with Antony Williams who gave a really nice back story as to our interest in data quality.

If it was not for Joe Olechno contacting us in early 2012 I would be none the wiser and the PLOS paper would not have appeared. While I had worked in HTS in the late 90s and early 2000’s I had pretty much left that screening world behind and not kept in touch with technological developments. The use of sound for moving liquids was as alien to me as the electric lightbulb must have been to those using gaslamps. I am sure this is also the case for many scientists still today.I was attracted to probing this further and seeing what pretty simple modeling could do. I did not expect what we found. And I certainly did not expect the responses from reviewers and journals that we had. I have had a much more balanced set of responses from audiences at an ACS local meeting in Raleigh last year, the SLAS meeting early this year and the recent ACS in New Orleans.

So lets think of all the places that dispense liquids to do analysis…Think about every hospital tox lab, think about those companies that analyze your biofluids for you, think about the contractors that look at the effect of compounds on the environment using animal or in vitro models (and the money that pours into this). It’s definitely not an issue just relevant to pharma, or med chemists (because lets face it there are far fewer of them). Just imagine do we think the labs in China, India etc. are dispensing with acoustic methods?

Do we think that all pharmas have shifted to acoustic? No what about those that use acoustic and tip-based dispensing together (why). An informal chat with an AZ employee mentioned their wholesale shift to acoustic dispensing 3-4 years ago. My guess is they kept it pretty quiet because it was acompetitive advantage, but then again it is likely all the top pharma’s did the same. Just goes to show the need for some precompetitive work in this area, or perhaps comparison of different dispensing techniques. And then there is my recent blog about the job opening at NIH regarding big data . Surely the kinds of analyses that we have done should be a requirement of the NIH. I am not aware that they have published on different dispensing techniques. I certainly have not seen meta data in PubChem or any other database that tells you what technique was used for dispensing.

So when PLOS tells us that our press release has statements regarding my nightmares that are “over-reaching in their representation of the study results.” and reiterate this via Twitter.. Well fine, they are my nightmares, they are very real and until someone clears up what is going on they are going to likely continue. Do we waste more time and money ignoring the issue of which technique to use for dispensing or does someone do the experiment (and fund it)?

Here are some of the responses to those comments on the  “in the pipeline blog”

8. Computationally Entertained on May 3, 2013 10:58 AM writes…

It reminds me of the complaints I had for a recent paper titled “do medicinal chemists learn from activity cliffs? …”

http://pubs.acs.org/doi/abs/10.1021/jm400147j

 

SE – This is interesting – could mode of liquid transfer suggest activity cliffs that are spurious?

 

In response to

9. Stephan on May 3, 2013 11:06 AM writes…

I think (hope) everybody in assay development is familiar with the sticky wall and volatile plate issues.
Our production folks certainly are. If I ask them to package 100µl of 1µg/ml (there aren’t any moles in their lab) detector antibody they ask if that is for immediate use (fine) use any time after after 2 weeks @ 4°C (fine, they will adjust the conc.), or to be used anywhere between 12h and 14 days after bottling (good luck, you are on your own).

 

SE – Clearly not a lot of people are aware of issues with compound dilution, stickiness, leaching or otherwise represented in the early references cited in the PLOS paper. Just using Google Scholar you can see the number of citations is very low and the much larger number of citations for the Science paper – likely due to higher exposure than the other journals? I think we were justified in trying to bring the issue into the open.

Ref 1

Pharmacological evaluation of different compound dilution and transfer paradigms on an enzyme assay in low volume 384-well format

T Spicer, Y Fitzgerald, N Burford, S Matson… – Drug Discovery …, 2005 – picoliterinc.com

Page 1. Pharmacological Evaluation of Different Compound Dilution and Transfer
Paradigms on an Enzyme Assay in Low Volume 384-well Format. Tim Spicer, Yvonne
Fitzgerald, Neil Burford*, Sandra Matson, Moneesh Chatterjee

Cited by 8

Ref 2

CITATION][C] Assay sciences: A model for improving efficiency through centralization

J Wingfield, D Jones, R Clark, P Simpson – American Drug Discovery, 2008

Cited by 4

Ref 3

Achieving accurate compound concentration in cell-based screening: validation of acoustic droplet ejection technology

RJ Grant, K Roberts, C Pointon… – Journal of …, 2009 – jbx.sagepub.com

Abstract Compound handling is a fundamental and critical step in compound screening
throughout the drug discovery process. Although most compound-handling processes within
compound management facilities use 100% DMSO solvent, conventional methods of

Cited by 14

Ref 4

Best practices in compound management for preserving compound integrity and accurately providing samples for assays

SL Matson, M Chatterjee, DA Stock… – Journal of …, 2009 – jbx.sagepub.com

Abstract Preserving the integrity of the compound collection and providing high-quality
materials for drug discovery in an efficient and cost-effective manner are 2 major challenges
faced by compound management (CM) at Bristol-Myers Squibb (BMS). The demands on

Cited by 13

Ref 5

Gradient, contact-free volume transfers minimize compound loss in dose-response experiments

D Harris, J Olechno, S Datwani… – Journal of biomolecular …, 2010 – jbx.sagepub.com

Abstract More accurate dose-response curves can be constructed by eliminating aqueous
serial dilution of compounds. Traditional serial dilutions that use aqueous diluents can result
in errors in dose-response values of up to 4 orders of magnitude for a significant

Cited by 6

Ref 6

Bioactive contaminants leach from disposable laboratory plasticware

GR McDonald, AL Hudson, SMJ Dunn, H You… – Science, 2008 – sciencemag.org

Abstract Disposable plasticware such as test tubes, pipette tips, and multiwell assay or
culture plates are used routinely in most biological research laboratories. Manufacturing of
plastics requires the inclusion of numerous chemicals to enhance stability, durability, and

Cited by 82

Ref 7

Nonylphenol ethoxylate plastic additives inhibit mitochondrial respiratory chain complex I

C Belaiche, A Holt, A Saada – Clinical chemistry, 2009 – Am Assoc Clin Chem

Am J Physiol 1998;274:1127-1139. ↵ McDonald GR, Hudson AL, Dunn SM, You
H, Baker GB, Whittal RM, et al. Bioactive contaminants leach from disposable
laboratory plasticware. Science (Wash DC) 2008;322:917. Abstract

Cited by 7

 

In response to

12. darwinsdog on May 3, 2013 12:04 PM writes…

In additional to adhesion to plastic surfaces, I would wonder about aggregation of cmpds (think Brian Shoichet) or other physical effects related to the properties of each cmpd that manifest by diff. dispensation methods.

SE – I am aware of this work and I think its worth testing as well – now if we could get our hands on the compunds..We tried to engage AZ at the outset but no joy.

 

21. darwinsdog on May 3, 2013 1:35 PM writes…

@16,19 First of all the paper in question is a meta analysis of data from other papers. So take it for what it is worth and realize that a lot more may be a variable here than just the dispensation method alone (usual list when changing assay protocols all the way to material lots over time) but it makes for a point to blog about and count as a PLOS publication (for whatever that gets you). But back to the detergent control – I do not know if the original papers included detergent controls in an attempt to address aggregation but I can tell you in general pharma companies (at least the ones I know about first hand) don’t usually dedicate wells in a plate to this type of control (I guess the cmpd libraries are deemed to sufficiently cover the ‘palmolive-space’ :-) .

SE – Yes it is a meta analysis of data from same lab AZ in same patents..Actually just blogging about this was not considered because so few people read the blog, it had to go somewhere that was accessible. Hence the first attempts being science. We think part of the problem is the earlier papers on the tip vs acoustic differences were just not in widely read places.If you ask 99% of biologists and chemists (and probably physicists) they would have no idea of this issue..

As for PLOS, while it is not the same caliber as Science – it is very visible, it is free to the reader, the review process was fast and more reasonable than other journals tried (Science & Anal Chem).

24. cdsouthan on May 3, 2013 2:53 PM writes…

Time for a CASFEAR competition “Critcal Assesment For Enzyme Assay Reproducability”

Just send a few reference compounds (with LogP spread) out to 20 to 50 labs and ask for the IC50s and Ki’s back with some linearity curves thrown in. Then write the paper.

SE – -Chris – good idea – though just a comparison across dispensing techniques with a big set of compounds with structures that are accessible and open data would suffice to start with..

25. Hap on May 3, 2013 3:28 PM writes…

I can see why it wasn’t in Science, but I wouldn’t have agreed that it belonged in a medicinal chemistry journal.

How do journals get all the pretty biological data they show? In some cases (maybe a lot), there aren’t exogenous components in the assays or their standards and so aggregation/other issues during dispensing aren’t issues, but in the remaining cases components which may not behave correctly are added exogenously. Without further data, you can’t assume that all compounds behave like this (maybe the set of compounds used was funny in some way that led to the observed behavior), but I’d not be betting the house, its furniture, or even the toys that this doesn’t happen elsewhere. Doesn’t that possibility make an awful lot of biological data look less secure? If it does, that would be important to a lot of people.

SE – Perhaps you have a point, except the leaching work appeared in Science and this issue is on a par with that IMHO. The earlier work by AZ and BMS put out in posters and talks shows much bigger numbers of compounds as described in the paper and shown on Derek’s blog. They show the same issue so it is not just one lab, one target, or one set of hairy compounds.

 

30. Jose on May 3, 2013 10:40 PM writes…

I think it’s an important finding, but did they seriously think it was Science worthy enough to submit not once, but TWICE?

Thanks Jose. We addressed the editor comments and added text to broaden the relevance – because lets face it – it is not just med chemists or those in pharma that rely on dilution with tips (see comments above).. and tried again, and failed. Probably should have tried a third time?

May
04

Open Drug Discovery Teams – An example of a lean start-up as an app

I have written quite a bit in the past on this blog about how the Open Drug Discovery Teams app was created with Alex Clark and how we have used it to highlight rare and neglected diseases, share molecules via Twitter and so much more! We think this is an example of a lean start-up, a very lean start-up in fact because it consumes a small piece of that 150% of the time we are working!

So if you want all the news to date we have created and updated a new slideset that extensively describes the app and what we plan on in the future. Well now we have updated the user guide too SO NOW YOU HAVE SOMETHING ELSE TO READ.

We think there is a whole array of other topics we could add, so if there is a rare disease with a good network of patient advocates and scientists that you think would benefit from being in the app, just let us know, send us an image we can use and some hashtags PLEASE..

We would also like to hear how you use the app and what other features you might like to see in the future. I am sure as the year progresses we will update you on how we are using ODDT..

Please tell everyone about this FREE app. If you are a company or organization that want to use what is in ODDT for a project or new app of your own please also get in touch.

May
03

What it took to get the paper out

Our new paper took a while to make it out into the world..here is a view of reviews and editorial decisions..This is just the tip of the iceberg..the initial reviews and in most cases rejections are shown below.

So first we tried Science as a Brevia…The review came back in 7 May 2012 – - rejected

(Note some addresses and phone numbers, emails etc removed to avoid spammers)

Manuscript number: 1224145
Dear Dr. Ekins:
Thank you for submitting your manuscript “Dispensing Processes Impact Computational and Statistical Analyses” to Science. Because your manuscript was not given a high priority rating during the initial screening process, we will not be able to send it out for in-depth review. Although your analysis is interesting, we feel that the scope and focus of your paper make it more appropriate for a more specialized journal. We are therefore notifying you so that you can seek publication elsewhere.
We now receive many more interesting papers than we can publish. We therefore send for in-depth review only those papers most likely to be ultimately published in Science. Papers are selected on the basis of discipline, novelty, and general significance, in addition to the usual criteria for publication in specialized journals. Therefore, our decision is not necessarily a reflection of the quality of your research but rather of our stringent space limitations.
Sincerely,
Jake S. Yeston, Ph.D. Senior Editor
Then we tried Science again.. 14 June 2012 again rejection
Manuscript number: 1225655
Dear Dr. Ekins:
Thank you for resubmitting your manuscript “Dispensing Processes Impact Assays and Analyses” to Science. I regret that we still feel the scope and focus of the manuscript would be more appropriate for publication in a medicinal chemistry journal, where practitioners in the field are still likely to see it and appreciate the implications. We are now receiving more than ten times the number of submissions that we have space to publish, and so are obligated to turn away a great deal of outstanding work. We wish you every success in publishing the study elsewhere.
Sincerely,
Jake S. Yeston, Ph.D. Senior Editor

Then we tried Analytical chemistry Oct 11 – 2012 – Apparently the editor sent out 6 invites for review and only one responded..They rejected it

Journal:  Analytical Chemistry Manuscript ID: ac-2012-02719s Title: “Dispensing Processes Profoundly Impact Biological Assays and Computational and Statistical Analyses” Author(s): Ekins, Sean; Olechno, Joe; Williams, Antony
Dear Dr. Ekins:
I am reporting on the above manuscript, which you recently submitted for consideration in Analytical Chemistry.
After a careful study of the manuscript and considering the reviewers’ comments, I regret to inform you that I have decided against publication.  The potential usefulness of your work is not in question.  However, in light of the reviewers’ evaluation and comments, I do not believe that publication is justified.  I hope you will find the reviewers’ specific comments helpful in planning future work.  These comments are either included here or, if they were given in the form of a file, will appear at the bottom of the copy of this letter which will appear and be stored in your Author Center.
I appreciate the opportunity to have considered this contribution, and thank you for your interest in Analytical Chemistry.
Kind regards,
John Yates Associate Editor Analytical Chemistry

————————————
Reviewer(s)’ Comments to Author: Reviewer: 1
Recommendation: Should not be published in Analytical Chemistry.
Comments: This paper compares two liquid handling approaches, namely, the acoustic vs. tip-based dispensing.  Table 1 is the key table for this comparison, indicating values for LogP and LogD parameters.  While there are differences between N=14 and N=16, the first and last data columns, N=14 (acoustic) and N=24 (tip-based) show no statistically significant differences and closely match each other.  This indicates that increasing the sample size analyzed (i.e., number of samples) with the tip-based approach can off-set the error.  Based on my experience in 3 pharmaceutical companies, these types of correlations (using a tip-based approach) is often done with a large sampling size (N=50, N=100,…) anyway.  Thus, the paper does not present a convincing case and should not be published in Analytical Chemistry.  Lastly, bunch of measured acoustic IC50 data is missing from Table 2 and 3 which makes the matter more confusing.
Additional Questions: Originality: Poor
Technical Quality: Poor
Clarity of Presentation: Fair
Importance to Field: Poor
The authors have addressed all necessary safety concerns.: Yes
The length of the article, including the number of figures, is appropriate for its content.: Yes

 So we tried Analytical Chemistry again rejection came 23rd Dec 2012 – good Xmas present.

Journal:  Analytical Chemistry
Manuscript ID: ac-2012-03094v
Title: “The Impact of Dispensing Processes on Biological Assays Determined by Computational and Statistical Analyses”
Author(s): Ekins, Sean; Olechno, Joe; Williams, Antony

Dear Dr. Ekins:

I am reporting on the above manuscript, which you recently submitted for consideration in Analytical Chemistry.

After a careful study of the manuscript and considering the reviewers’ comments, I regret to inform you that I have decided against publication.  The potential usefulness of your work is not in question.  However, in light of the reviewers’ evaluation and comments, I do not believe that publication is justified.  I hope you will find the reviewers’ specific comments helpful in planning future work.  These comments are either included here or, if they were given in the form of a file, will appear at the bottom of the copy of this letter which will appear and be stored in your Author Center.

I appreciate the opportunity to have considered this contribution, and thank you for your interest in Analytical Chemistry.

Kind regards,

John Yates
Associate Editor
Analytical Chemistry

Reviewer(s)’ Comments to Author: Reviewer: 1 Recommendation: Not appropriate subject matter for Analytical Chemistry; recommend the following journal Journal of Biomolecular Screening (http://jbx.sagepub.com/) Comments: I have read the authors’ revisions and continue to believe that the paper lacks the criteria suitable for publication in Analytical Chemistry. Additional Questions: Originality: Fair Technical Quality: Fair Clarity of Presentation: Fair Importance to Field: Poor The authors have addressed all necessary safety concerns.: Yes The length of the article, including the number of figures, is appropriate for its content.: Yes

Reviewer: 2 Recommendation: Publish either as is or subject to minor revisions as indicated. Comments: review attached Additional Questions: Originality: Good Technical Quality: Clarity of Presentation: Good Importance to Field: Good The authors have addressed all necessary safety concerns.: Yes The length of the article, including the number of figures, is appropriate for its content.: Yes

Reviewer:3 Recommendation: Should not be published in Analytical Chemistry. Comments: General comments: 1.    Article addresses concepts at the interface of computational and experimental drug discovery that cannot be adequately summarized in “Letter format”. 2.    The authors state “no previous publication has analyzed or compared such data based on tip-based and acoustic dispensing”. As such this reviewer feels that a detailed (full manuscript) explanation is required for correlating pharmacophore modeling and compound dispensing. Detailed comments: (1)    The authors cite all computational methods used in this research. The use of this analysis to highlight differences between contact and non-contact dispensing is not adequately explained and cannot really be described in a “Letter format” manuscript. (2)    The authors describe highly specialized techniques such as (i) pharmacophore models, (ii) derivation of affinity from these models and (iii) correlation of affinity data with contact vs non-contact dispensing. However they do not provide adequate justification and explanation for their methodology. (3)    The authors use a limited dataset (14 compounds at most) to derive models without an explanation of why their models are correct. (4)    The authors make emphatic statements such as “the result of which is likely to misdirect drug design” that are not justified from their findings on this small dataset. (5)    The authors do not discuss the assays used for tip-based and contactless dispensing. As such they cannot justify the correlation between these datasets, since differences in the assay protocol may give rise to the differential results and not the use of tip vs acoustic dispensing. Additional Questions: Originality: Fair Technical Quality: Poor Clarity of Presentation: Poor Importance to Field: Fair The authors have addressed all necessary safety concerns.: Yes The length of the article, including the number of figures, is appropriate for its content.: No

 reviewer 4. (this one is italicized because I like it)

In this reviewers opinion this paper highlights a critically important factor in the drug
discovery process, namely that the quality of the SAR models built by medicinal chemists is
dependent on the quality of the data generated from the screen. Understanding how the
properties of a compound impact on its potential behavior in a screen is vitally important.
Clearly if compounds have properties which make them difficult to dispense or cause them
to drop out of solution during the assay this will likely lead to an inappropriate estimate of
compound activity in that biological test environment. To maximize the understanding of
SAR space around any pharmacophore it is necessary to have accurate data from as many
exemplar molecules in that space as possible.
The data presented suggests that the physical handling of compounds is important in
ensuring a complete SAR picture is generated. While the data set used in this article is
relatively small, it clearly shows that it is possible to miss biologically relevant chemical
features from design sets when these features adversely impact on the handling properties
of the molecule. In effect library design is biased towards compounds that have good liquid
handling properties and solubility. While ultimately these properties may lead to success in
vivo, biasing library design early in hit identification and lead generation will limit medicinal
chemistry understanding of target engagement at a molecular level.
If the physical handling of compounds can have a profound effect on the IC50 data
generated in an assay due to the chemical properties of the molecule, it brings into question
the integrity of historical screening data sets. A key question would be what percentage of
compounds in any library have the physical properties that might generate erroneous data.
This question is only touched upon in this article and there is some unpublished (anecdotal)
evidence provided at the end of the paper to suggest the scale of the potential issue.
Comments to be addressed by authors:
1. The authors need to remove the word disposable when referencing the tip-based
dispensing. None of the AZ data referenced in this paper was generated with
disposable tip based Tecan Genesis instruments.
2. The authors need to be careful when citing differences between IC50 values. There
will be intrinsic variability between test events and therefore small differences
between IC50s may not be significant. Typical run to run variability in a biochemical
assay could easily result in 3 fold variability between IC50 estimations. In addition it
is more common to use the inverse log of the IC50 value when making comparisons
because the use of the log scale helps to standardize the errors between test events.
I would suggest that for the data presented here anything less than 4 fold difference
in IC50 could just be run to run variability rather than due to the compound handling
process.
3. Citation 14 seems to be inappropriately used on page 3 as it is used to support
statements regarding inhibition of the TK EphB4. The Comley paper is a review of
serial dilution vs direct dilution and is not related to the EphB4 data.
4. Second sentence of the abstract uses “dispensing” too frequently, would read better
if it started, “Data shows IC50 values obtained via tip based serial dilution versus
acoustic dispensing can differ by orders of magnitude…..” The statement as it stands
in the original paper is not only difficult to read but also implies that there is always a
difference between tip-bases IC50s and acoustic IC50s and this is not the case.
5. Sentence 3 page 3 requires softening. The statement that the two liquid handling
techniques generate conflicting results is not always true, only for a sub population of
compounds.

 

Then we tried PLOSONE:Feb 20 2013it was accepted

PONE-D-13-02029
Dispensing Processes Impact Apparent Biological Activity as Determined by Computational and Statistical Analyses
PLOS ONE

Dear Dr. Ekins,

Thank you for submitting your manuscript for review to PLOS ONE. After careful consideration, we feel that your manuscript will likely be suitable for publication if it is revised to address the points below. Therefore, my decision is “Minor Revision.”

We invite you to submit a revised version of the manuscript that addresses the following points:

Please correct the different points asked by the reviewers.

We encourage you to submit your revision within forty-five days of the date of this decision.

When your files are ready, please submit your revision by logging on to http://pone.edmgr.com/ and following the Submissions Needing Revision link. Do not submit a revised manuscript as a new submission. Before uploading, you should proofread your manuscript very closely for mistakes and grammatical errors. Should your manuscript be accepted for publication, you may not have another chance to make corrections as we do not offer pre-publication proofs.

If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter.

Please also include a rebuttal letter that responds to each point brought up by the academic editor and reviewer(s). This letter should be uploaded as a Response to Reviewers file.

In addition, please provide a marked-up copy of the changes made from the previous article file as a Manuscript with Tracked Changes file. This can be done using ‘track changes’ in programs such as MS Word and/or highlighting any changes in the new document.

If you choose not to submit a revision, please notify us.

Yours sincerely,

Alexandre G. de Brevern, Ph.D.
Academic Editor
PLOS ONE

Reviewer’s Responses to Questions
Comments to the Author
1. Is the manuscript technically sound, and do the data support the conclusions?
The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.
Reviewer #1: Yes
Reviewer #2: Yes

Please explain (optional).
Reviewer #1: (No Response)
Reviewer #2: (No Response)

2. Has the statistical analysis been performed appropriately and rigorously?
Reviewer #1: I don’t know
Reviewer #2: Yes

Please explain (optional).
Reviewer #1: Needs further revision
Reviewer #2: (No Response)

3. Does the manuscript adhere to standards in this field for data availability?
Authors must follow field-specific standards for data deposition in publicly available resources and should include accession numbers in the manuscript when relevant. The manuscript should explain what steps have been taken to make data available, particularly in cases where the data cannot be publicly deposited.
Reviewer #1: Yes
Reviewer #2: Yes

Please explain (optional).
Reviewer #1: (No Response)
Reviewer #2: (No Response)

4. Is the manuscript presented in an intelligible fashion and written in standard English?
PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors below.
Reviewer #1: Yes
Reviewer #2: Yes

Please explain (optional).
Reviewer #1: (No Response)
Reviewer #2: (No Response)

5. Additional Comments to the Author (optional)
Please offer any additional comments here, including concerns about dual publication or research or publication ethics.
Reviewer #1: 1) Write the importance of Pharmacophoric fit values in the respective study.
2) Table 2. Statistical analysis results for statistically significant correlations with IC50. Note the correlation of LogP with 14 molecules using acoustic dispensing and how addition of more compounds results in correlations of LogP and LogD with tip-based dispensing. No correlations were observed for IC50 value against molecular weight, hydrogen bond donors, hydrogen bond acceptors, isoelectric point, polar surface area, molar refractivity.
How the authors consider this as statistically significant correlations with IC50. Though there is very less or no correlation at all between descriptors and activity. Justify the results.
3) How does the study can be carried forward in more general sense of wider applicability. Is this model robust enough for wider class of molecules for w.r.to studied set only??? The range of IC50 values studied. Is this model applicable for identifying less active compounds?
Reviewer #2: (No Response)

6. If you would like your identity to be revealed to the authors, please include your name here (optional).
Your name and review will not be published with the manuscript.
Reviewer #1: (No Response)
Reviewer #2: (No Response)

 SUMMARY

We used all the preceding reviewer comments and each time the manuscript changed. We also had our own ideas of what else to add and remove. Imagine the final paper is bloated compared to the approx 1000 (word) version originally written and the relatively short communication sent to Analytical Chemistry. If I had any advice for scientists in the same position it would be “do not give up! Science is clearly not interested! Analytical Chemistry would not recognize something of relevance if it bit them in the rear.”

As I blogged previously, everything with the final home for the manuscript was going well until the 11th hr when the poop hit the fan on the press release. Just goes to show that sometimes when you think its over, well it isn’t.

 

 

May
02

Press releases that morph

I thought long and hard about publishing this blog, so it is with a sense of sadness and complete loss that I write these words. My interest in trying to publish in Open Access (OA) journals died yesterday.

Yesterday should have been an exciting day with a new article coming out in an OA journal, the culmination of a year and half of real time and many hundreds of hours of work with collaborators. Unfortunately for me it was spoilt at the 11th hour by (IMHO) an over-reaching OA publisher that wanted complete control over a press release (that had been crafted by many people including a professional journalist to make it pretty accessible to the non-expert). I wanted to convey what I have already discussed in several presentations, most recently at the ACS. The topic and the repercussions of the work are cause to give me “nightmares”. That did not go down very well.

Here is the press release that came out and below are two statements in the email from the publisher and how I originally intended them (bold is text removed). The collaborating group obviously made the changes before the press release appeared on their website. I was only alerted to why the changes were made after the fact.

….The last two paragraphs in your press release state:
 
“Incorrect processes can have a dramatic effect on chemical testing for many areas, including health and the environment.
 
“This is a nightmare situation that can keep you awake at night,” Ekins said. He urges scientists to ask questions about the data they use. How much of a database is generated using pipette methods? How much is erroneous? How does it affect all subsequent science and conclusions?”
 
Based on my reading and input from our internal staff, these statements are over-reaching in their representation of the study results. As you’re aware, incorrect processes and erroneous data have extremely strong implications to the scientific process, researchers and the general population affected by environmental and health research, so please rephrase or remove these lines.
 
We would appreciate it if we could ensure the most responsible communication possible for this significant piece of research. Please let me know if you have further questions or would like to discuss outreach for this research in greater detail, and please provide us with a revised draft of the release prior to sending it out………

You may think as I have been told …”Put it down to experience”, “these things happen”, “grow a thicker skin”, “don’t come off as a jerk or a hothead” ….In all my time publishing and the few times a press release has come out, I have never seen this kind of control over ones own words happen. In the big scheme of things a press release is ‘water off a ducks back’, but the implications are that this OA publisher, who was paid to publish the article (which BTW was not NIH funded), demands control over what you say in the press release. I think others need to be aware what can happen. For me this is just as big a ‘nightmare’ as the problem we pointed out in the paper. I will not be submitting this blog to the publisher for approval.

 

 

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