Amgen, seeking to crash Novo's party, links bispecific to weight loss months after end of dosing

Amgen plans to start a phase 2 dose-ranging trial early next year. (Nuthawut Somsuk/iStock/Getty Images Plus)

Amgen’s late run for the obesity market is gathering pace. In phase 1, recipients of the highest dose of the company’s would-be challenger to Novo Nordisk’s Wegovy maintained double-digit percentage weight loss 150 days after receiving the last of three subcutaneous shots. 

The phase 1 clinical trial has enrolled 110 people with obesity, but without diabetes, across single- and multiple-ascending dose stages. Amgen shared an early look at the data last month, revealing a 14.5% reduction in body weight at the highest dose after 12 weeks, and used the World Congress on Insulin Resistance, Diabetes and Cardiovascular Disease Hybrid Conference to share an update on Saturday.

In the update, researchers showed what happened to body weight in the weeks after the final dose. The news is encouraging for Amgen, with percentage body weight loss in the high-dose cohort slipping over the 150 days after the third dose to come in at 11.2%. 

Buoyed by the finding, Amgen plans to start a phase 2 dose-ranging trial of the bispecific GIPR antagonist and GLP-1 receptor agonist early next year.

Amgen is arriving late to the party. Novo Nordisk won FDA approval for Wegovy as a treatment for chronic weight management last year, and Eli Lilly’s Mounjaro could secure a nod in the indication by the end of next year. 

Both drugs have triggered significant weight reductions in large clinical trials. Novo Nordisk secured approval after linking Wegovy to placebo-adjusted weight loss of 10.3% and 12.4% in a pair of 68-week studies. Lilly went one better in its phase 3 trial, reporting placebo-adjusted weight loss of 17.8% in the 72-week SURMOUNT-1 study. Data from Lilly’s second trial are due in 2023.

A slew of other drug developers including AstraZeneca, Boehringer Ingelheim and Pfizer are studying molecules in patients with obesity, either in isolation or with comorbidities such as nonalcoholic steatohepatitis. Amgen is taking a different approach than its rivals, pursuing a GIPR antagonist amid a sea of GIPR agonists in the belief that both activating and inhibiting the receptor cause weight loss.