Altimmune gears up for FDA meeting on pivotal Phase 3 trial in alcohol use disorder

Altimmune is gearing up to talk to the FDA next month about a pivotal program for its glucagon/GLP-1 dual receptor agonist pemvidutide, which reduced drinking in patients with alcohol use disorder in a mid-stage study.

The biotech, which shared topline results from the Phase 2 RECLAIM trial in July, provided another look at the data Monday at a meeting of the American Association for the Study of Liver Diseases (AASLD) in Denver. Investigators randomized about 100 people with alcohol use disorder (AUD) to receive pemvidutide or placebo once weekly for 24 weeks, together with a standardized behavioral intervention.

As reported in July, the trial met its primary endpoint. Compared to baseline, patients on pemvidutide had 4.2 fewer heavy-drinking days per week during weeks 21 to 24 of the trial. Patients on placebo had 2.75 fewer heavy-drinking days per week. The result was “highly statistically significant,” Altimmune said in July.

Now, Altimmune has scheduled an end-of-Phase 2 meeting with the FDA for next month to discuss the design of the Phase 3 registrational program for AUD.

In a note to investors, William Blair analysts named the 38% reduction in serum phosphatidylethanol (PEth)— a direct biomarker for alcohol consumption—versus a 5.9% increase with placebo, as the “strongest validation for pemvidutide in this indication.” Altimmune first disclosed the serum PEth data in its July release of topline results.

Noting the limitations of cross-trial comparisons, “pemvidutide appears to exhibit a more robust clinical profile than short-duration low-dose semaglutide,” the analysts said. A Phase 2 trial in February 2025 found weekly heavy-drinking days fell from two to less than one in 48 patients who took semaglutide, the GLP-1 receptor agonist that Novo sells as Ozempic and Wegovy, for nine weeks.

The potential benefits of GLP-1s in AUD have long intrigued biopharma.

Last year, Eli Lilly started two Phase 3 trials of brenipatide in adults with AUD. Lilly designed each trial to enroll 1,100 patients with AUD to assess whether taking brenipatide, a GLP-1/GIP receptor agonist, for 56 weeks changes drinking patterns. The studies are scheduled to wrap in early 2028, according to the federal trial database.

Noting the size and duration of the Lilly studies, William Blair said, “We believe Altimmune will require additional capital to fund a pivotal program in AUD.” Altimmune ended June with $519 million in cash, cash equivalents and investments. The biotech recently began a Phase 3 trial of pemvidutide in the liver disease metabolic dysfunction-associated steatohepatitis (MASH).

While the analysts believe pemvidutide has shown therapeutic activity in MASH, they have doubts about whether the Phase 2b data demonstrate clear clinical differentiation. As they noted, the MASH market is increasingly competitive, with Madrigal Pharmaceuticals’ Rezdiffra and Novo’s Wegovy already out there, and Boehringer Ingelheim and Lilly advancing assets through the clinic.