08:48 AM EST, 11/26/2024 (MT Newswires) -- (Updates with additional details throughout the story and the latest stock movement in the seventh paragraph.)

Amgen ( AMGN ) said Tuesday a phase 2 study showed that its investigational obesity drug MariTide demonstrated up to 20% average weight loss after a year in people living with obesity or overweight without type 2 diabetes without plateauing.

The study also showed that patients with type 2 diabetes achieved up to 17% average weight loss, also without plateauing, Amgen ( AMGN ) said.

The most common adverse reactions in the phase 2 trial were gastrointestinal related, including nausea, vomiting, and constipation, Amgen ( AMGN ) said, adding that nausea and vomiting were reduced with increased dosage.

Additionally, the company said it did not observe any weight loss plateau in either study group, while there was no link between the administration of MariTide and bone mineral density changes.

The trial admitted 592 adult participants in two groups living with obesity or overweight.

The company said it is currently working on a second part of the study to evaluate any further weight loss with continued treatment after 52 weeks, adding that it will start a phase 3 Maritime program in obesity and obesity-related conditions.

Amgen's ( AMGN ) stock fell 12% in recent Tuesday premarket activity.