Amgen drops an early-stage obesity candidate

Amgen said on August 4, 2026, that it discontinued development of AMG 513, an obesity candidate that had been in Phase 1 testing ^[1][2]. The decision leaves MariTide as Amgen's only obesity treatment in late-stage development ^[1]. One Phase 1 study of AMG 513 will keep running so that participants already enrolled can finish the study as planned, but no new work on the drug is moving forward ^[1].

AMG 513 never reached later-stage trials, so it was not close to being available to patients outside of research studies. Amgen has not published a public explanation of why the program was dropped, and the sources used for this article do not give a reason. That detail is not yet known.

MariTide is now carrying Amgen's obesity ambitions on its own. The drug is being tested in a Phase 3 program called MARITIME, which spans several conditions: chronic weight management, type 2 diabetes, cardiovascular outcomes, heart failure, and obstructive sleep apnea ^[1]. Amgen's second-quarter 2026 financial results, also released August 4, show research and development spending rising 7% on a GAAP basis and 10% on a non-GAAP basis compared with the same period in 2025, driven in part by higher spending on later-stage clinical programs, "primarily those related to MariTide" ^[2]. The company reported total revenue of $10.1 billion for the quarter, up 10% year over year ^[2].

Why it matters for patients

For people currently using or considering GLP-1 medications like Ozempic, Wegovy, Mounjaro, or Zepbound, this news does not change anything about those approved drugs. AMG 513 was never available to the public and was still years away from a possible approval, if it had continued. Its discontinuation mainly affects the future pipeline of obesity treatments rather than anyone's current prescription.

The bigger signal is about competition. Amgen is now putting its resources behind a single obesity candidate, MariTide, rather than developing several drugs at once. That kind of narrowing is common in drug development, where companies frequently trim early-stage programs to focus money and staff on the candidates furthest along and considered most likely to succeed. MariTide itself remains investigational. It has not been approved by the Food and Drug Administration and is still being studied in Phase 3 trials across multiple conditions ^[1].

For patients who were enrolled in the discontinued Phase 1 study of AMG 513, Amgen said that one such study will continue so those participants can complete it as originally planned ^[1]. That detail matters for people already in that trial, but it does not open the drug to new patients.

What happens next

The sources reviewed here do not give a timeline for MariTide's Phase 3 MARITIME results or for when Amgen might seek FDA approval. Those dates are not yet known based on the available reporting. Amgen's R&D spending trends, including continued investment tied to MariTide, were disclosed as part of its second-quarter 2026 financial results, but no specific readout or filing date for MariTide was included in that same disclosure ^[2]. Readers following the broader competitive landscape, including regulatory and trial news for other GLP-1 medicines, can expect ongoing coverage as those programs report results.