Swiss drugmaker Roche announced positive topline Phase II data for its once-weekly GLP-1/GIP receptor agonist CT-388, supporting the drug candidate as it progresses into Phase III study. The CT388-103 Phase II trial recruited 469 adults living with obesity, with CT0388 demonstrating clinically meaningful and statistically significant weight loss.
A once-weekly subcutaneous injection of CT-388 (titrated up to 24 mg) produced a placebo-adjusted weight loss of 22.5% at 48 weeks on the highest tested dose and showed a clear dose-response relationship. The study did not observe a weight loss plateau by Week 48. At the 24 mg dose, 95.7% of participants achieved ≥5% weight loss, 87% reached ≥10%, 47.8% achieved ≥20%, and 26.1% achieved ≥30% weight reduction versus baseline. Additionally, 73% of participants with pre-diabetes at baseline treated with CT-388 normalized blood glucose at Week 48, compared with 7.5% in the placebo arm.
CT-388’s safety and tolerability profile was generally consistent with other incretin-class therapies, with mostly mild-to-moderate gastrointestinal adverse events and a low rate of discontinuations due to adverse events.
Roche is advancing CT-388 into Phase III obesity trials (Enith1 and Enith2) this quarter and is also evaluating it in an additional ongoing Phase II study in people with obesity and type 2 diabetes.
Roche has moved to stock its obesity and metabolic disease pipeline both organically and inorganically. The Swiss firm acquired CT-388 via the USD 2.4 billion purchase of Carmot Therapeutics completed in 2024, while a major co-development partnership was struck with Zealand Pharma in March 2025 for amylin analog petrelintide, currently Phase II stage. Also acquired via Carmot is a once-daily GLP-1 pill, CT-996/RG6652, which has produced Phase I data, while in-house candidate GYM329, a myostatin inhibitor, is the subject of Phase I study.