Bristol Myers Squibb Delays Key Alzheimer's Psychosis Trial for Cobenfy Amid Site Irregularities

Bristol Myers Squibb (BMS) has announced a significant delay in the readout of its closely watched ADEPT-2 trial, evaluating the drug Cobenfy for Alzheimer's disease psychosis. The pharmaceutical giant cited "irregularities" in trial execution at some study sites, pushing the expected results to 2026.

Trial Setback and Regulatory Response

BMS revealed that it had identified irregularities in the conduct of the ADEPT-2 study at a small number of sites. In response, the company has taken several steps:

• Patient data from the affected sites will be excluded from the primary analysis.
• After consulting with the FDA, an independent party was brought in to assess the collected data.
• A data monitoring committee recommended continuing the trial and enrolling additional participants to meet the original target.

Laura Gault, head of neuroscience drug development at BMS, emphasized the company's commitment to maintaining study integrity, stating, "Our decision to exclude patient data from sites where irregularities were observed reflects our unwavering commitment to safeguarding the integrity of our studies."

Impact on Cobenfy's Development Timeline

The ADEPT-2 trial delay has significant implications for Cobenfy's development in Alzheimer's psychosis:

• Results are now expected by the end of 2026, a year later than previously anticipated.
• Two other phase III trials, ADEPT-1 and ADEPT-4, are still on track to deliver data by the end of 2026.
• BMS maintains that at least two positive trials are required for regulatory filing, suggesting the overall approval timeline may not be affected.

This setback follows an earlier disappointment for Cobenfy in April 2025, when it failed to show significant benefits as an adjunctive treatment for schizophrenia in the ARISE study.

Market Reaction and Analyst Perspectives

Despite the delay, BMS shares saw an unexpected rise, trading up almost 5% following the announcement. Analysts offered mixed interpretations of this market response:

William Blair analyst Matt Phipps suggested that investors might view the trial continuation as a positive sign, noting, "If there was no signal, why bother increasing enrollment?"

Conversely, Carter Gould of Cantor Fitzgerald cautioned that while a delay might be preferable to negative results in the short term, it "stops far short of de-risking Cobenfy" in Alzheimer's psychosis or bolstering BMS's broader growth profile.

The ADEPT-2 trial's outcome remains crucial for BMS, as the company faces patent expirations on its top-selling drugs Eliquis and Opdivo in the coming years. With Alzheimer's psychosis affecting an estimated 3-3.5 million patients in the U.S., Cobenfy represents a significant market opportunity for BMS in its efforts to offset looming revenue losses.