Amgen Inc. (AMGN) delivered encouraging news about its obesity drug MariTide at the J.P. Morgan Healthcare Conference on Monday, and it's the kind of update that matters in the increasingly competitive weight-loss drug market: patients kept the weight off, and they didn't feel terrible doing it.

What Amgen Found

CEO Robert Bradway shared results from the second part of MariTide's Phase 2 study, and here's what stood out. Most participants maintained their weight loss from year one for another full year while taking either a lower monthly dose or a quarterly dose. That quarterly dosing schedule is notable because nobody wants to stick themselves with needles more often than necessary.

The second year went smoothly from a safety perspective. Patients tolerated MariTide well, including those on quarterly doses, with very low rates of nausea and vomiting. Those side effects have been a persistent complaint with existing weight-loss drugs, so this is actually a big deal. No new safety concerns popped up either.

Beyond weight loss, MariTide maintained improvements in cardiometabolic parameters throughout the second year at effective maintenance doses.

The Bigger Picture

Back in June 2025, Amgen released full results from part one of the Phase 2 study. MariTide delivered up to 20% average weight loss in people with obesity but without Type 2 diabetes, and up to 17% in those with diabetes. Both groups significantly outperformed placebo.

A separate 24-week study tested monthly MariTide specifically for Type 2 diabetes patients with or without obesity. Results showed clinically meaningful reductions in both HbA1c levels and weight.

Amgen now has six Phase 3 studies running for MariTide across obesity and related conditions including diabetes, heart disease, and sleep apnea.

What Analysts Think

William Blair wasn't particularly surprised by the 52-week update, given what was already known from every-eight-weeks dosing data. There's still uncertainty about what dose would work best for quarterly maintenance, especially since the 420 mg dose level isn't being studied in current Phase 3 trials.

Analyst Matt Phipps sees MariTide as differentiated from currently approved GLP-1 therapies and those in late-stage development. That differentiation could translate into meaningful market share and a multibillion-dollar peak sales opportunity. Phipps maintains an Outperform rating on the stock, citing revenue upside potential from key assets and late-stage pipeline success.

Amgen (AMGN) stock traded up 0.46% at $325.80 at publication on Wednesday.