After finding ‘irregularities,’ Bristol Myers to extend key trial of Cobenfy in Alzheimer’s psychosis

Data from a closely watched study evaluating Bristol Myers Squibb’s mind-stabilizing medicine Cobenfy in patients with Alzheimer’s disease could now come a year later than expected.

In late July, Bristol Myers executives said they were reviewing the company’s near-term clinical trials to ensure the “timely delivery” of results with the “highest probability of success.” The review included “ADEPT-2,” a late-stage experiment exploring whether Cobenfy, which is already used to treat schizophrenia, may also have positive effects on the moderate to severe psychosis that often accompanies Alzheimer’s.

On Wednesday, Bristol Myers disclosed that it had identified “irregularities” in the way the study was conducted at a “small number” of sites. This discovery prompted the company to not only exclude patient data from those sites for the study’s primary analysis, but, after consulting with the Food and Drug Administration, also bring in an “independent party” to assess the data that had been collected.

Based on that party’s findings, a data monitoring committee recommended the trial keep going and enroll more participants so as to hit its original target. Bristol Myers is following this advice. ADEPT-2 had recruited around 400 patients across 119 locations, according to its listing on a federal database of clinical trials.

The company now expects results to come by the end of 2026.

“Our decision to exclude patient data from sites where irregularities were observed reflects our unwavering commitment to safeguarding the integrity of our studies,” said Laura Gault, head of Bristol Myers’ neuroscience drug development, in a statement.

On Wall Street, the hope was that ADEPT-2 would produce results before the end of this year. The readout is “highly anticipated by investors,” according to William Blair analyst Matt Phipps, in part because of the “size of the market opportunity.” Roughly 7 million people in the U.S. have Alzheimer’s and, though estimates vary widely, it’s generally thought that between a quarter and a half experience related psychosis.

Clinical delays typically lead to stock sell-offs. Shares of Bristol Myers, however, were up almost 5% by mid-morning Wednesday, to trade at $50.60 apiece.

To Phipps, investors may be seeing the go-ahead from the FDA and data monitoring committee as a good sign, suggesting the trial data shows at least some positive trends. “[I]f there was no signal, why bother increasing enrollment?” he wrote in a note to clients.

Carter Gould, of the investment firm Cantor Fitzgerald, appears to hold a less-optimistic view. He expects the stock gain is presumably because a “no news” or “delayed news” is better than negative results. “That may work in the near-term,” Gould wrote in his own note, “though we would argue this update stops far short of de-risking Cobenfy” in Alzheimer’s psychosis or Bristol Myers’ broader growth profile.

“While there’s clearly a scenario whereby ADEPT-2 could still [succeed], none of this suggests an overwhelmingly positive result, and all of our past issues with this trial and setting remain,” he added.

Prior to Wednesday, Bristol Myers’ shares had fallen 15% from the start of the year. The pharmaceutical giant is set to lose patent protection on its two top-selling drugs — the blood thinner Eliquis and the cancer immunotherapy Opdivo — over the next couple years. Efforts to offset those looming losses have been mixed.

Last month, Bristol Myers stopped early the first of three late-stage studies testing an experimental anticoagulant it’s been co-developing with Johnson & Johnson. The partners have pegged this drug, milvexian, as a potential multibillion-dollar product. Bristol Myers has also reported stumbles this year in heart disease and a type of anemia.