New Weight-Loss Drug Delivers 15.5% Reduction — Can It Rival Wegovy and Mounjaro?
An experimental Roche obesity drug helped people with type 2 diabetes and overweight or obesity lose an average of 15.5% of their body weight over 48 weeks at the highest tested dose, strengthening Roche’s position in the rapidly expanding market for weight-loss medicines.
The once-weekly injectable, called enicepatide or CT-388, also produced substantial improvements in blood sugar control in a Phase II trial. The drug remains investigational and has not been approved for commercial use.
Roche obesity drug: What did the trial show?
The CT-388-104 study enrolled 447 adults living with type 2 diabetes and overweight or obesity in a randomized, double-blind, placebo-controlled Phase II trial lasting 48 weeks.
Participants receiving the highest titrated dose of 24 mg achieved an average 15.5% reduction in body weight by week 48, according to Roche.
The company said the weight-loss curve had not reached a demonstrable plateau by the end of the study, although that does not establish how much additional weight participants might lose with longer treatment.
At the same dose, average HbA1c fell by 2.65 percentage points from a baseline of 8.1%.
Roche said 90% of participants in the 24 mg group reached an HbA1c level of 6.5% or lower, while 62% reached levels below 5.7%, which is outside the diagnostic range for diabetes.
How does enicepatide work?
Enicepatide is a once-weekly injectable that targets both the GLP-1 and GIP receptors, hormonal pathways involved in appetite, blood sugar regulation and energy balance.
Its mechanism therefore has similarities to tirzepatide, the active ingredient in Eli Lilly’s Mounjaro for diabetes and Zepbound for chronic weight management, which also targets GLP-1 and GIP receptors.
Wegovy, by contrast, contains semaglutide and primarily targets the GLP-1 receptor.
Those mechanistic similarities do not demonstrate that enicepatide is equivalent or superior to Wegovy, Mounjaro or Zepbound. The latest Roche trial was not a direct head-to-head study against any of those medicines.
Does 15.5% weight loss make it a Wegovy or Mounjaro rival?
The results strengthen Roche’s position in the obesity-treatment race, but they cannot be used on their own to rank enicepatide against medicines already on the market.
The latest study involved people with type 2 diabetes, whose weight-loss responses can differ from those of people living with obesity without diabetes.
Clinical trials also vary in design, dosing, patient characteristics and duration, making cross-trial comparisons less reliable than direct head-to-head studies.
Reuters said the findings nevertheless reinforce Roche’s ambitions to challenge Novo Nordisk and Eli Lilly, which currently dominate the global obesity-drug market.
What were the side effects?
Roche said enicepatide’s safety and tolerability profile was generally consistent with the established incretin drug class.
The most common adverse events were predominantly mild-to-moderate gastrointestinal effects.
About 2% of participants in the enicepatide treatment groups discontinued therapy because of adverse events, compared with no such discontinuations in the placebo group.
Longer and larger studies will still be needed to establish the drug’s safety profile before regulators can consider approval.
Roche expands its weight-loss drug pipeline
The September results follow earlier positive Phase II findings for enicepatide in people with obesity or overweight without type 2 diabetes.
Roche has already moved the drug into Phase III studies for chronic weight management and plans additional late-stage studies focused on glycemic control and cardiovascular outcomes.
The program forms part of a broader Roche push into cardiometabolic medicine as the company attempts to establish a significant presence in obesity, diabetes and related cardiovascular conditions.
Weight-loss market could reach $100–150 billion
Obesity medicines have become one of the pharmaceutical industry’s most competitive global markets.
Industry estimates cited by Reuters suggest the weight-loss drug market could be worth between $100 billion and $150 billion by 2030 as companies develop new injectable and oral treatments.
Profile News has previously examined the next generation of weight-loss treatments emerging in 2026 as competition expands beyond the first wave of GLP-1 drugs.
It has also covered recent U.S. regulatory findings involving weight-loss medicines.
When could Roche’s obesity drug reach patients?
There is currently no approved launch date for enicepatide, and the drug remains under clinical investigation.
Roche must complete larger Phase III studies assessing efficacy and safety over longer periods before potentially seeking regulatory approval.
The 15.5% result therefore represents an important clinical milestone rather than the launch of a new obesity medicine.
If later-stage studies confirm the findings with an acceptable safety profile, enicepatide could give Roche a significant entry into a market where companies are competing on weight-loss efficacy, glucose control, tolerability and convenience.
Sources
- Reuters — Roche’s obesity drug boosts blood sugar control and drives 15.5% weight loss
- Roche — Positive Phase II results for enicepatide
- Roche ForPatients — Enicepatide CT-388-104 trial details
- Reuters — Competition heats up in weight-loss drug market
- Reuters — Novo CEO sees major shift in obesity drug market by 2030
