Amgen stock crashed Tuesday after its weight-loss drug met Wall Street's expectations, but was only on par with Eli Lilly's Zepbound.

Amgen's experimental drug MariTide helped overweight or obese patients lose up to 20% weight on average in a year-long mid-stage trial, data that missed lofty investor expectations and sent the shares down 8% before the bell on Tuesday.

Amgen said its experimental weight loss injection helped patients lose up to 20% of their weight on average after a year in a critical mid-stage trial. The company said it did not observe a plateau, which indicates the potential for further weight loss beyond 52 weeks.

Analysts were expecting the treatment to achieve an average weight loss of about 20% to 25% after one year of treatment, making it competitive with Eli Lilly & Co. Inc.’s Zepbound.

Amgen Inc (NASDAQ: AMGN) says patients on its weight-loss injection in a mid-stage trial weighed up to 20% less on average after a year. The biopharmaceutical giant is convinced its treatment will help lower body weight even further upon continued consumption (beyond 52 weeks) as it did not observe a plateau in the Phase II study.

Amgen's experimental drug MariTide led to an average weight loss of up to 20% in a year-long mid-stage trial of nearly 600 people who were overweight or obese, the company said on Tuesday.

An Amgen obesity drug helped participants lose a substantial amount of weight, but questions about how competitive it could be remain

Amgen (NASDAQ:AMGN) today announced positive data at 52 weeks in a double-blind, dose-ranging Phase 2 study with MariTide (maridebart cafraglutide, formerly AMG 133), an investigational antibody peptide conjugate subcutaneously administered monthly or less frequently.

Upcoming data from a mid-stage study of Amgen's experimental weight-loss drug MariTide will shed light on how well it might measure up against the popular GLP-1 drugs sold by Eli Lilly and Novo Nordisk .