Journal mulls expression of concern for Cassava Sciences paper

A journal is considering issuing an expression of concern for a 2005 paper by authors tied to a company that’s now under investigation for fraud, Retraction Watch has learned. 

[See an update on this post (bottom).]

The article, “Ultra-low-dose naloxone suppresses opioid tolerance, dependence and associated changes in mu opioid receptor–G protein coupling and Gβγ signaling,” was written by a group linked to Pain Therapeutics, Inc., which in 2019 changed its name to Cassava Sciences.

Last week, the Wall Street Journal reported that the U.S. Securities and Exchange Commission and the National Institutes of Health were investigating claims that the company manipulated data for simulfilam, its experimental drug for Alzheimer’s disease. 

As we reported in August, a law firm submitted a “citizen’s petition” to the FDA citing: 

grave concerns about the quality and integrity of the laboratory-based studies surrounding this drug candidate and supporting the claims for its efficacy. …

The petition cites three main areas of concern: Unreliable biomarker data, questionable methodology in key experiments and suspect Western blots in papers that constitute the backbone of Cassava’s regulatory finding (along with a grant application to the National Institutes of Health). The articles — which appear in Neuroscience, Biological Psychiatry, PLOS ONE, and other journals, were written by Hoau-Yan Wang, of City University of New York (CUNY), and Lindsay Burns, a Cassava employee. 

The company has pushed back on the allegations, which were followed by critiques on PubPeer by Elisabeth Bik and others.

Juan Lerma, the editor-in-chief of Neuroscience, told us that an expression of concern had been drafted but not published: 

We issued an expression of concern [for the 2005 article] … However, the authors of the paper originating concern have been able to find the original uncropped blots and send them to me. I am evaluating them now and will make a decision soon.

Lerma added: 

I stopped publication [of the notice] as soon as authors sent the material to me. Indeed, this was planned for publication early this week. I believe that the authors have the right [to have] their allegations be considered. 

The article has been cited 125 times, according to Clarivate Analytics’ Web of Science.

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4 thoughts on “Journal mulls expression of concern for Cassava Sciences paper”

  1. The author of the Citizen’s Petition is Labaton Sucharow who stated that they represent clients who are actively short the stock for Cassava.

  2. When short sellers are making allegations against a company, it is clear that they are financially motivated and it is hard to give much credence to their concerns. Pain Therapeutics gave up on pursuing a better analgesic and moved to studying Alzheimer’s, when they realized it was a much more productive direction to pursue, based on what they learned during their research. The NIH presumably believed in Cassava’s direction, when they decided to fund their research. To my understanding, the phase 2 study that had problems in their results, showed atypical variation in results in the placebo group, which should not happen. Cassava then found another company to perform the testing, as it seemed the first lab had competency problems. The re-evaluation of results eliminated the placebo variation problem and gave believable results. This is all on Cassava’s website in their press releases, for anyone to review.

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