With data from a mid-stage trial showing weight loss of up to 12.3% at 28 weeks in patients treated with PF’3944, “Pfizer is moving full speed into obesity clinical development,” BMO Capital Markets said Tuesday.
Fresh off its bidding war with Novo Nordisk to acquire Metsera, Pfizer has released its first-ever readout from the company’s obesity pipeline, touting weight-loss that exceeded 12% at the highest dose level tested.
“Pfizer is moving full speed into obesity clinical development,” BMO Capital Markets said in a note to investors on Tuesday.
Pfizer presented data from the long-acting GLP-1 injectable MET-097i—now known as PF’3944—In the Phase IIb VESPER-3 study. The drug was given first as weekly subcutaneous injections to initiate patients, before transitioning them to monthly dosing. The trial used four titration protocols, each with various strengths and schedules, as well as a placebo control arm, according to a Tuesday news release.
At the medium dose arm—which involved weekly injections of 0.4 mg ramping up to 1.2 mg before hitting 4.8 mg monthly—patients achieved 12.3% placebo-adjusted weight loss at 28 weeks. A lower dose arm, which topped out at 3.2-mg monthly injections, reached 10% placebo-adjusted weight reduction.
In a note to investors Tuesday morning, analysts at BMO Capital Markets said these weight-loss results “look competitive” with other commercially available therapies. The group offered Novo’s semaglutide, which hit placebo-adjusted weight loss of around 9% at 28 weeks in the Phase III STEP-1 study, as an example. Eli Lilly’s tirzepatide, meanwhile, reached 13% at the same time point in the Phase III SURMOUNT-1 trial.
Patients in both treatment groups showed no plateau effect at the time of readout—an outcome Pfizer said points to the “robust and continuous weight loss” with PF’3944, even after switching to a monthly regimen. The pharma expects patients’ body weights to continue to drop through 64 weeks of follow-up.
Pfizer will take both the low and medium dose schedules into Phase III development, the company said on Tuesday.
Pfizer has an “expansive” late-stage program planned for PF’3944, one that will span 10 Phase III studies addressing various patient populations and comorbidities. These include the recently launched VESPER-4, which will look at weekly doses in patients who have obesity or are overweight but don’t have type 2 diabetes. Another trial, dubbed VESPER-5, will focus on those with type 2 diabetes.
Aside from these monotherapy trials, investors will also be on the lookout for potential combination regimens with MET-233i, an amylin asset also acquired in the Metsera purchase, according to BMO.
“Any data regarding combination with [PF’3944] and the asset’s relative competitive profile . . . will be key as we continue to evaluated [sic] Pfizer’s positioning in the evolving obesity market,” the analysts added.
Pfizer in September last year had initially planned to acquire Metsera for $4.9 billion, an offer that was easily eclipsed by Novo’s rival proposal of $8.5 billion. A fierce—not to mention messy—bidding war ensued, and while Pfizer came out on top, the victory came at a hefty price tag of around $10 billion.
And while Tuesday’s data for PF’3944 “appear supportive of a competitive mono-agonist profile,” they nevertheless “leave some questions” as Pfizer builds to a full release in June this year, BMO said.
