ATX-101 for reduction of submental fat: A phase III randomized controlled trial.

Background: ATX-101, an injectable form of deoxycholic acid, causes adipocytolysis when injected subcutaneously into fat.

Objective: We sought to evaluate the efficacy and safety of ATX-101.

Methods: In this phase III trial (REFINE-2), adults dissatisfied with their moderate or severe submental fat (SMF) were randomized to ATX-101 or placebo. Coprimary end points, evaluated at 12 weeks after last treatment, were composite improvements of 1 or more grades and 2 or more grades in SMF observed on both the validated Clinician- and Patient-Reported SMF Rating Scales. Other end points included magnetic resonance imaging-based assessment of submental volume, assessment of psychological impact of SMF, and additional patient-reported outcomes.

Results: Among those treated with ATX-101 or placebo (n = 258/treatment group), 66.5% versus 22.2%, respectively, achieved a composite improvement of 1 or more grades (Mantel-Haenszel risk ratio 2.98; 95% confidence interval 2.31-3.85) and 18.6% versus 3.0% achieved a composite improvement of 2 or more grades in SMF (Mantel-Haenszel risk ratio 6.27; 95% confidence interval 2.91-13.52; P < .001 for both). Those treated with ATX-101 were more likely to achieve submental volume reduction confirmed by magnetic resonance imaging, greater reduction in psychological impact of SMF, and satisfaction with treatment (P < .001 for all). Overall, 85.7% of adverse events in the ATX-101 group and 76.9% in the placebo group were localized to the injection site.

Limitations: Follow-up was limited to 44 weeks.

Conclusion: ATX-101 is an alternative treatment for SMF reduction.