Roche reported positive topline results from CT388-103, a Phase II study of CT-388, its investigational dual GLP-1/GIP receptor agonist for obesity. The trial showed clinically meaningful and durable weight loss with once-weekly dosing. No weight-loss plateau was observed at 48 weeks.
Key efficacy highlights
At the highest tested dose (24 mg):
- 22.5% placebo-adjusted weight loss (efficacy estimand)
- 18.3% placebo-adjusted weight loss (treatment-regimen estimand; p < 0.001)
- Clear dose–response relationship
Weight-loss responder rates at Week 48:
- 95.7% achieved ≥5% loss
- 87.0% achieved ≥10% loss
- 47.8% achieved ≥20% loss
- 26.1% achieved ≥30% loss
Strong metabolic signal in pre-diabetes
Among participants with pre-diabetes at baseline:
- 73% on CT-388 24 mg achieved normal blood glucose
- 7.5% on placebo achieved normal blood glucose
This suggests potential benefit beyond weight reduction alone.
Safety and tolerability
CT-388 was generally well tolerated.
- Most gastrointestinal events were mild to moderate
- Discontinuation due to adverse events:
- 5.9% with CT-388
- 1.3% with placebo
Safety was consistent with the incretin drug class.
What Roche says?
Levi Garraway, MD, PhD, Roche’s chief medical officer:
The robust weight loss combined with a well-tolerated safety profile reinforces our confidence as we advance to Phase III trials.
What’s next for CT-388?
Roche has designated CT-388 as a fast-track asset.
Ongoing and planned development:
- Additional Phase II study in obesity with type 2 diabetes (CT388-104)
- Phase III obesity program (Enith1 and Enith2) expected to start this quarter
- Evaluation as a potential combination partner with petrelintide
Why CT-388 may be differentiated?
CT-388 is designed with:
- Potent GLP-1 and GIP receptor activation
- Minimal ß-arrestin recruitment
- Reduced receptor internalisation and desensitisation
This biased signaling profile is expected to support prolonged pharmacologic activity.
Bottom line
CT-388 shows best-in-class-range weight loss, durable response through 48 weeks, and a tolerable safety profile. Roche is positioning it as a cornerstone of its cardiometabolic pipeline and a future combination backbone.
