Amgen has ended development of its early-stage obesity drug AMG 513, foisting its hopes for a slice of the massive weight loss market onto the shoulders of phase 3 candidate MariTide.
A phase 1 study of the scrapped asset will continue for patients already enrolled, the California biopharma announced today during its second-quarter earnings call.
AMG 513 was previously hit with a clinical hold by the FDA in February 2025, which was lifted a few months later. At the time, Amgen leaders said they didn’t think the hold was related to AMG 513 and that they still expected to pursue development of the candidate.
The cull of AMG 513 echoes that of AMG 786, another phase 1 obesity drug that Amgen discontinued back in early 2024. Back then, the company’s R&D leader Jay Bradner, M.D., said the decision was made after 786 “just did not meet” the bar set by MariTide.
He added that in addition to MariTide, Amgen would continue to invest in preclinical obesity assets. One of those ultimately became AMG 513, which kicked off its first-in-human study that fall.
The same high bar that sank AMG 786 was ultimately AMG 513’s undoing as well.
“The bar is high at Amgen for obesity medicines,” an Amgen spokesperson told Fierce, adding that more will be shared about 513 “in due course.”
Other preclinical obesity prospects are still in the works, the spokesperson added, including those with incretin and non-incretin mechanisms.
With 513 joining 786 on the scrap heap, all of Amgen’s near-term obesity dreams now rest with MariTide, an antibody-peptide conjugate designed to both activate the GLP-1 receptor and inhibit the glucose-dependent insulinotropic polypeptide receptor (GIPR) with potentially just four to six doses per year.
Amgen’s sprawling phase 3 program for MariTide includes tests of the drug’s potential in weight loss, cardiovascular risk, Type 2 diabetes and obstructive sleep apnea. Key readouts on MariTide’s ability to cut weight will come next year.