Efficacy and Safety of CBL-514 Injection in Reducing Abdominal Subcutaneous Fat: A Randomized, Single-Blind, Placebo-Controlled Phase II Study

Abstract Background A small-molecule injectable drug, CBL-514, has shown promising efficacy and safety for subcutaneous fat reduction. Objectives To further evaluate the efficacy and safety of CBL-514 for abdominal subcutaneous fat reduction. Methods In this single-blind, randomized, parallel-group, placebo-controlled Phase 2 trial, 76 participants were randomized (2:1) to receive up to four CBL-514 treatments (2mg/cm², maximum 600mg/treatment) or placebo, administered subcutaneously to the abdomen every 4 weeks. Two follow-up visits were conducted at 4 and 8 weeks post-final treatment. Changes in abdominal subcutaneous fat thickness and volume were measured by ultrasound. The primary endpoint was the proportion of participants with subcutaneous fat volume loss of ≥150mL from baseline compared with placebo. Results In the intention-to-treat (ITT) population, a significantly higher proportion of CBL-514-treated participants achieved ≥150mL subcutaneous fat volume reduction from baseline compared with placebo-treated participants at both follow-up visits. At 8 weeks post-final treatment, 69.6% of CBL-514-treated participants lost ≥150mL subcutaneous fat, compared with none in the placebo group (p<0.001). Moreover, 60.9% of participants in the CBL-514 group further achieved the ≥200 mL subcutaneous fat loss threshold. Of the 28 participants in CBL-514 group (N=50) who lost ≥150mL subcutaneous fat, 42.9% (12/28 participants) achieved this target after a single treatment. The most common treatment-emergent adverse events were injection site reactions and were of mild to moderate severity. Conclusions CBL-514 treatment significantly reduced abdominal subcutaneous fat volume with a favorable safety profile. As a non-invasive treatment, CBL-514 could be a new, promising alternative therapy for effective targeted subcutaneous fat reduction.