Data from the phase 3, open-label, long-term safety study of Brickell Biotech’s sofpironium bromide gel, 5% and 15%, provided clinically meaningful improvement in axillary hyperhidrosis severity as measured by the Hyperhidrosis Disease Severity Measure-Axillary (HDSM-Ax), a proprietary patient-reported outcome scale. For both dose groups, respectively, responders with a 1-point (86.1%; 85.8%) and 2-point (69.4%; 61.9%) improvement on HDSM-Ax PRO scale showed a gradual and continual improvement in sweat severity through 48 weeks of treatment.

Results of the ARGYLE study, assessing the long-term safety and efficacy of topical, once-daily treatment with sofpironium bromide for 48 weeks in patients nine years and older with primary axillary hyperhidrosis, were presented at the 2021 AAD VMX.

Overall, the safety, tolerability and efficacy results for sofpironium bromide gel, 5% and 15% in ARGYLE were consistent with prior clinical experience and no unexpected safety findings were observed. There were no clinically significant changes in laboratory parameters or vital signs over 48 weeks of treatment.

Treatment-related treatment-emergent adverse events (TEAEs) for sofpironium bromide gel, 5% (22.5%) and 15% (50.8%) were mostly mild or moderate in severity and transient in nature. The most common and expected treatment-related TEAEs reported were blurred vision (4.9%; 18.8%), dry mouth (8.8%; 16.8%), pruritis (5.9%; 14.7%), pain (3.9%; 14.7%), dermatitis (5.9%; 9.1%), erythema (4.9%; 7.6%), irritation (4.9%; 5.6%), mydriasis (1.0%; 5.1%) and urinary retention (2.9%; 3.6%). The patient discontinuations due to treatment-related TEAEs included blurred vision (2.0%; 7.1%), pruritis (0%; 2.0%), dermatitis (1.0%; 2.0%), dry mouth (0%; 1.5%), pain (0%; 1.5%), erythema (1.0%; 0.5%), irritation (0%; 1.0%), urinary hesitation (1.0%; 0%) and mydriasis (0%; 0.5%). 

“We are pleased that the ARGYLE study results further strengthen the safety, tolerability and efficacy data previously observed in our Phase 2b study of sofpironium bromide gel,” says Deepak Chadha, Brickell’s Chief Research & Development Officer. “As was observed with earlier clinical studies, the majority of side effects were mild or moderate in severity and transient in nature. Sofpironium bromide gel, 5% and 15% both led to sustained improvements in sweating severity for the majority of patients through the end of 48 weeks of treatment. These data contribute to our understanding of the long-term use of sofpironium bromide gel as a potential novel treatment for the millions of patients suffering from this chronic and debilitating condition.”

“In this LTSS study, sofpironium bromide gel was generally well-tolerated with continued efficacy during 48 weeks in patients with primary axillary hyperhidrosis. In addition, we were pleased to see that the incidence of patients with any treatment-emergent adverse events decreased over time, as did the number of discontinuations,” says Stacy Smith, MD, a practicing dermatologist and participating investigator in this study. “Taking into consideration that patients did not have the conventional option to acclimate to treatment prior to enrolling in this standalone long-term safety study, the observed safety profile is even more encouraging.”