Roche Obesity Shot Led to 18% Weight Loss in Study
(Bloomberg) — Roche Holding AG said patients on its experimental shot lost 18% more weight than those who got placebo in a study that will help set the stage for the Swiss drugmaker to compete in the lucrative obesity market.
Almost half of the volunteers treated with the highest dose shed 20% or more of their body weight by week 48 of the mid-stage trial, Roche said Tuesday.
The results are the first in a raft of mid-stage results due out this year from five key experimental drugs as Roche pushes to reach the top three of the obesity market despite a relatively late start in the field. The drugmaker acquired much of its obesity pipeline in its $3.1 billion purchase of Carmot Therapeutics Inc. in 2023.
Roche shares rose as much as 1.1% in early Zurich trading. They have climbed about 7% so far this year, more than the Bloomberg index tracking European biotech and pharma companies.
The Roche shot delivered weight loss that appears on par with Eli Lilly & Co.’s blockbuster Zepbound and better than Novo Nordisk A/S’s Wegovy, said Michael Leuchten, an analyst for Jefferies. Roche will need to show how it can make the drug stand out in “an increasingly crowded market,” Leuchten said. “They need to show a path to commercial relevance.”
Other drugmakers developing weight-loss medicines, besides Lilly and Novo, include AstraZeneca Plc and Pfizer Inc., which won a heated bidding war for obesity specialist Metsera Inc. late last year.
Roche’s weekly shot, called CT-388, was part of the Carmot portfolio and works in a similar way as Zepbound.
Most gastrointestinal side effects were mild to moderate, and 5.9% of the people on the shot quit the trial due to health impacts — a figure Roche said was low for the class.
Combination Therapy
In another measure of the drug’s effectiveness, Roche estimated that it would have delivered 22.5% weight loss if all the patients had stuck to taking it as planned in the trial. The gap between the two figures suggests that patients may have not adhered to some of the doses, according to Leuchten.
Roche said it will start late-stage trials this quarter. The drugmaker eventually plans to test it not just as a standalone therapy, but also in combination with other obesity treatments.
The results show the shot has the potential to be the best in its class, said Manu Chakravarthy, Roche’s global head of cardiovascular, renal and metabolism product development. Crucially, weight loss didn’t seem to have reached a plateau by week 48, suggesting the drug could help people lose even more if they took it longer.
In its late-stage programs, Roche will offer three different doses to “cover the spectrum” of weight loss that patients need, he said. In order to manage side effects, the company used what he called a “low and slow” approach to moving patients up to stronger doses, increasing the dose of the shot just once every four weeks.
“That’s probably the right regimen and gives us confidence,” Chakravarthy said.
(Updates with analyst comment in the fifth paragraph, executive comment from 10th paragraph)
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