Trial By Error: My Follow-Up Letter to Professor Rona Moss-Morris

By David Tuller, DrPH

Ten days ago, I sent a letter to Professor Rona Moss-Morris of King’s College London, seeking information about the licensing deal involving her web-based program of cognitive behavior therapy to treat irritable bowel syndrome. Since I have not heard back, this morning I made a second attempt to reach out to her and obtain some answers to my questions.

In both letters, I have made it clear that I would be happy to post any response she should send me on Virology Blog–at full length and without editorial interruption from me. I feel now I have done my due diligence in soliciting her input. I doubt I will reach out to her a third time–although I do not categorically exclude the possibility, depending on developments. (The subject line for my latest e-mail: “reaching out a second time about IBS, CBT and Mahana Therapeutics”)


Dear Professor Moss-Morris,

It has been more than a week since I wrote about my concerns involving the Mahana Therapeutics licensing deal for Regul8, the web-based CBT program for irritable bowel syndrome. I have also reached out to Mahana Therapeutics itself, but have not received any response. (I have cc’d Mahana on this e-mail, along with Professor Vincent Racaniello, the Columbia University microbiologist who hosts Virology Blog.)

Mahana’s declarations in the press release and website have focused primarily on the ACTIB findings related to symptom severity reduction. I am aware the study also reported very modest benefits for the web-based group over treatment-as-usual on the other self-reported instruments. This should not be especially surprising after a round of CBT and does not necessarily have much or anything to do with actual reductions in IBS symptom severity.

As I mentioned in my last message, my invitation to post your comments on Virology Blog–at any length and without interruption–is a standing offer. In the meantime, I have some specific questions as well:

1. The Mahana Therapeutics press release stated that improvements in symptom severity from the web-based program were “substantial” and “durable.” The website states that the web-based program produced €œdramatic and potentially game-changing€ benefits and documents this claim with results from the IBS-Symptom Severity Scale. On this scale, the 35.2-point difference between the mean scores of participants in the web-based arm and the treatment-as-usual arm was less than the 50-point threshold that represents clinically significant change in an individual. And the negligeable 12-point severity scale difference between the mean scores of the two groups at 24 months was not statistically significant. Do you believe it is accurate and appropriate for Mahana to describe these results as “substantial,” “durable,” €œdramatic,” and “potentially game-changing€?

2. The Mahana Therapeutics website also declares that, at 12 months, 66% of those in the web-based arm reduced their IBS-SSS scores by 50 or more points. The website does not mention that 44% of participants who received treatment-as-usual and provided data at 12 months also achieved that threshold. Do you agree that the omission of that important detail tends to create the impression that all the reported improvements should be attributed to the web-based program? Do you believe the Mahana Therapeutics website should also mention that 30% of the trial participants did not provide these 12-month responses, so their IBS-SSS outcomes are unknown? 

3. You indicated that you did not receive payment from Mahana Therapeutics until the study was submitted. Post-submission, when did you receive such payment or payments, and how much have you received to date? Before becoming a paid advisor, were you consulting with or advising Mahana Therapeutics or a precursor group in an unpaid capacity? When did you receive the Manaha Therapeutics stock options, and how many stock options have you received?

In the Mahana press release about the licensing deal, you are quoted as praising the company for being an “amazing collaborative partner.” Presumably, such a stellar partner should be presenting information that genuinely reflects, rather than hypes and exaggerates, the ACTIB findings on clinical efficacy. 

For full transparency, I will post this letter on Virology Blog, as I did the previous one. Once again, I look forward to hearing from you. Thanks much!


David Tuller, DrPH
Senior Fellow in Public Health and Journalism
Center for Global Public Health
School of Public Health
University of California, Berkeley

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