An experimental weight-loss injection developed by Amgen Inc., administered less frequently compared to popular treatments from Eli Lilly & Co. and Novo Nordisk A/S, appears to sustain weight loss even after treatment cessation.

According to a recent study published in the journal Nature Metabolism, patients receiving monthly injections of Amgen’s drug, dubbed MariTide, experienced weight loss of up to 14.5% of their body weight within 12 weeks. Impressively, some participants maintained weight loss for up to 150 days post-treatment discontinuation.

Narimon Honarpour, Amgen’s senior vice president of global development, described this as a remarkable characteristic of MariTide. Investors and analysts have been eagerly awaiting updates on the drug since Amgen first presented early results in 2022. The latest study provides the most comprehensive insight yet, as MariTide progresses through mid-stage trials, with further results expected later this year.

MariTide functions differently from Wegovy or Zepbound as it is an antibody-drug conjugate (ADC), a type of molecule typically used in targeted cancer treatment. It consists of an antibody blocking the GIP receptor and two peptides mimicking the gut hormone GLP-1, designed to stick around in the body longer than weekly weight-loss shots.

Initially developed as a treatment for obesity, Amgen is now testing MariTide in diabetic patients, contrary to the development path of weight-loss drugs from Eli Lilly and Novo Nordisk. Insights from human genetics prompted Amgen’s decision to inhibit GIP based on associations with decreased BMI.

The study, involving 110 obese patients, primarily aimed to assess MariTide’s safety and tolerability but revealed its significant impact on weight loss. Those receiving the highest single dose experienced up to 8.2% weight loss after 92 days, indicating sustained effects.

Safety profiles were comparable to other GLP-1 drugs, with nausea and vomiting being the most common side effects. Mild gastrointestinal issues prompted four patients in the highest dose group to withdraw before receiving a second shot.

While early results are promising, further studies are necessary before MariTide becomes available to patients. Amgen considers this a crucial step, alongside ongoing work on an oral weight-loss drug expected to yield results in the first half of the year.