A 44-Week Open-Label Study Evaluating Safety and Efficacy of Topical Glycopyrronium Tosylate in Patients with Primary Axillary Hyperhidrosis.

BACKGROUND: Glycopyrronium tosylate is a topical anticholinergic approved in the USA for primary axillary hyperhidrosis in patients aged ≥ 9 years (Qbrexza™ [glycopyrronium] cloth, 2.4%). OBJECTIVE: This 44-week open-label extension study assessed glycopyrronium tosylate safety and descriptive efficacy in patients completing one of two, phase III, double-blind, vehicle-controlled, 4-week trials (NCT02530281; NCT02530294). METHODS: Patients aged ≥ 9 years with primary axillary hyperhidrosis were randomized 2:1 (glycopyrronium tosylate: vehicle, once daily) in the double-blind trials. Completers could receive open-label glycopyrronium tosylate for up to an additional 44 weeks. Treatment-emergent adverse events and local skin reactions were assessed. Descriptive efficacy assessments were gravimetrically measured sweat production, Hyperhidrosis Disease Severity Scale responder rate (≥ 2 grade improvement), and Dermatology Life Quality Index/children's Dermatology Life Quality Index. RESULTS: Of 651 patients completing the double-blind trials, 564 (86.6%) entered the open-label extension; 550 were analyzed. Most patients experiencing treatment-emergent adverse events had mild or moderate events (> 90%). Discontinuation because of treatment-emergent adverse events remained low and relatively stable, with a cumulative rate of 8.0% (44/550) over 44 weeks. Common treatment-emergent adverse events (> 5%) were dry mouth (16.9%), vision blurred (6.7%), application-site pain (6.4%), nasopharyngitis (5.8%), and mydriasis (5.3%). Most patients (67.5%) had no local skin reactions; those occurring were predominantly mild/moderate. Glycopyrronium tosylate efficacy was maintained throughout the trial; at week 44, the Hyperhidrosis Disease Severity Scale responder rate was 63.2%, and improvements from baseline (double blind) in sweat production were - 71.3% and 8.7 ± 6.2/6.2 ± 4.9 for Dermatology Life Quality Index/children's Dermatology Life Quality Index. CONCLUSIONS: Daily long-term application of glycopyrronium tosylate for up to 48 weeks (double blind plus open label) was generally well tolerated and efficacy was maintained. No new safety signals emerged. TRIAL REGISTRY: Clinicaltrials.gov NCT02553798.