Amgen prepares Phase III for weight-loss drug, boosts production

Investor enthusiasm for obesity treatments is far from dwindling, as evidenced by Amgen's significant after-hours stock surge. Following an optimistic update on its experimental weight-loss drug AMG 133, also known as maridebart cafraglutide (MariTide), Amgen observed a remarkable 14% increase in its stock value. If this trend persists, the pharmaceutical giant's market capitalization could soar by nearly $20 billion. During a recent call to discuss the company’s quarterly earnings, CEO Bob Bradway expressed confidence in the interim Phase II data for MariTide, stating, “The interim Phase II analysis is complete, and we are very encouraged with the results we’ve seen thus far. We believe that MariTide’s differentiated profile will address significant unmet medical needs.”

Although specific data from the study were not shared—topline results are expected by late 2024—Bradway highlighted the company's commitment to advancing MariTide into a Phase III program and scaling up manufacturing capabilities. The positive earnings call also revealed that Amgen outperformed sales and profit expectations for the quarter.

Chief Scientific Officer Jay Bradner emphasized MariTide’s potential during the investor call. He described the drug as a bispecific antibody that combines a GIP antagonist with two GLP-1 agonist peptides, setting a new standard for Amgen’s obesity medications. Based on interim findings, the company plans to swiftly move into a broad Phase III trial, targeting patients with obesity, diabetes, and possibly other obesity-related conditions. This could pave the way for a cardiovascular benefit approval, similar to the one Novo Nordisk’s Wegovy obtained earlier this year, enabling access for Medicare patients.

Bradner noted that MariTide will be administered using a convenient, handheld autoinjector, with monthly or even less frequent injections. This dosing regimen could provide a competitive edge over existing treatments like Wegovy and Eli Lilly’s Zepbound, which require weekly injections.

In addition to advancing clinical trials, Amgen is expanding its manufacturing capacity for MariTide, considering both clinical and commercial needs. Bradway expressed confidence in the company’s ability to meet manufacturing demands, citing Amgen's established expertise in biotherapeutic production. He highlighted that the company’s capital expenditure plans for the year include preparations to tackle the clinical and commercial challenges ahead.

Interestingly, Amgen has decided to discontinue the development of its small molecule obesity drug, AMG 786, following a Phase I trial. Bradner explained, “Given the profile we've seen with AMG 786, we will not pursue further development. Instead, we are focusing our investment on MariTide and several preclinical assets, including both oral and injectable programs.”

Investor sentiment towards MariTide has significantly improved since the mixed reception of its Phase I data in February. The bispecific antibody’s dual mechanism of action—GIP inhibition and GLP-1 activation—had been a point of uncertainty. Despite achieving dose-dependent weight loss in the Phase I trial, including an average of 14.5% at the highest dose level, the study faced challenges such as patient drop-outs and no meaningful changes in blood pressure or lipid levels. However, Bradner assured that the Phase II trial has not faced patient retention issues thus far.

Amgen also reported a strong financial performance for the first quarter, with revenues reaching $7.45 billion, a 22% increase from the previous year and slightly above analyst expectations. The revenue growth was driven by strong sales of treatments like Repatha for high cholesterol, Evenity for osteoporosis, and Blincyto for acute lymphoblastic leukemia. The company has revised its full-year revenue forecast to between $32.5 billion and $33.8 billion, raising the lower end of its previous estimate by $100 million. It also adjusted its earnings per share guidance to a range of $19 to $20.20, up from the earlier range of $18.90 to $20.30.