Amgen’s most advanced obesity asset MariTide is entering Maritime—that is, a phase 3 program that includes two freshly launched trials.
Historically, the California-based pharma has remained tight-lipped when it comes to plans for MariTide, a monoclonal antibody linked to a pair of peptides designed to boost GLP-1 receptor activity while tamping down on the receptor for GIP.
Now, Amgen’s R&D head Jay Bradner, M.D., has shared some information about the late-stage studies at the TD Cowen Health Care Conference.
The program, dubbed Maritime, includes one study for people living with obesity or overweight without Type 2 diabetes that is expected to enroll 3,500 participants. Called Maritime-1, the trial has a primary readout date slated for the beginning of 2027, according to ClinicalTrials.gov.
Meanwhile, Maritime-2 will recruit 999 people living with obesity or overweight with Type 2 diabetes, with a readout also expected in the start of 2027, according to the federal database.
The primary endpoint for both studies will measure the percent change from baseline in body weight at 72 weeks. Both trials are placebo-controlled and will test out three different doses of MariTide.
Amgen plans to use dose escalation in both studies but isn’t sharing more information around the dose schema at this time, Bradner said.
The MariTime program is expected to include other phase 3 trials in cardiovascular disease, heart failure, kidney disease and obstructive sleep apnea, though timing has not yet been announced for the additional studies.
MariTide is Amgen’s most advanced clinical obesity asset. In November, the company shared phase 2 data that linked monthly doses of the investigational treatment to average weight loss of up to 20% over 52 weeks in individuals with obesity or overweight.
The trial enrolled 592 adults who received either a monthly MariTide dose of 140 mg, 280 mg or 420 mg; an eight-week 420 mg dose; or placebo.
The 20% weight loss figure was reached by the 280 mg monthly patient group, with the pooled two 420 mg dosing regimens and the 140 mg monthly dose groups following slightly behind. A weight loss plateau was not observed for the MariTide cohorts, which Amgen said indicates the potential for further weight loss beyond 52 weeks.
While trial-to-trial comparisons are difficult, Leerink analysts said at the time that the findings were “roughly on par” with Eli Lilly’s weekly Zepbound (tirzepatide), meaning that MariTide’s “only differentiation appears to be dosing frequency.”
In response to a question from analysts on an earnings conference call, Bradner said that Amgen could “potentially” run a head-to-head trial of MariTide versus approved weight loss drugs, but he didn’t offer any concrete plans.
Amgen’s efforts in obesity have been shrouded in drama, with several prospects being axed and a hidden Excel tab containing data on bone density changes in a phase 1 MariTide trial temporarily wiping billions of dollars off the pharma’s market cap last November.
Previously, in May 2024, the company dropped an early-stage obesity candidate, known as AMG 786, to go all in on MariTide. Little information was shared about the terminated small-molecule program, with a release revealing only that a related phase 1 clinical trial had been completed.
More recently, Amgen’s mysterious asset—the company’s only other clinical obesity prospect called AMG 513—was hit by a clinical hold. The pause, reported at the beginning of February, impacts a phase 1 trial. Amgen hasn’t publicly shared the mechanism of AMG 513, but did say during its full-year earnings call that it doesn’t think the issue is related to the drug.