Unwanted submental fat (SMF) may result in an unattractive chin profile and dissatisfaction with appearance. An approved and rigorously tested non-surgical method for SMF reduction is lacking.
To evaluate the efficacy and safety of ATX-101 for the pharmacological reduction of unwanted SMF in a phase III randomized, double-blind, placebo-controlled study.
Patients (n = 360) with moderate or severe SMF were randomized to receive ATX-101 1 or 2 mg/cm2 or placebo injected into their SMF for up to four treatments ~28 days apart, with a 12-week follow-up. Coprimary efficacy endpoints were the proportions of treatment responders, defined as a ≥1-point reduction in SMF on the Clinician-Reported Submental Fat Rating Scale (CR-SMFRS), and those satisfied with their appearance in association with their face and chin after treatment on the Subject Self-Rating Scale (SSRS score ≥4). Secondary efficacy endpoints included a ≥1-point improvement in SMF on the Patient-Reported Submental Fat Rating Scale (PR-SMFRS) and changes in the Patient-Reported Submental Fat Impact Scale (PR-SMFIS). Additional patient-reported outcomes and changes in the Skin Laxity Rating Scale were recorded. Adverse events (AEs) and laboratory test results were monitored.
Compared with placebo, a greater proportion of patients treated with ATX-101 1 and 2 mg/cm2 showed a ≥1-point improvement in CR-SMFRS (58.3% and 62.3%, respectively, vs. 34.5% with placebo; P < 0.001) and patient satisfaction (SSRS score ≥4) with the appearance of their face and chin (68.3% and 64.8%, respectively, vs. 29.3%; P < 0.001). Patient-reported secondary efficacy endpoints showed significant improvements in SMF severity (PR-SMFRS; P = 0.009 for ATX-101 1 mg/cm2, P < 0.001 for ATX-101 2 mg/cm2 vs. placebo) and emotions and perceived self-image (PR-SMFIS; P < 0.001). No overall worsening of skin laxity was observed. AEs were mostly transient, mild to moderate in intensity and localized to the treatment area.
ATX-101 was effective and well tolerated, and may be an alternative to surgery for patients desiring improvement of their submental profile.