This clinical study will investigate the safety, tolerability, and preliminary efficacy of open-label KB111 in pediatric and adult subjects with Hailey-Hailey Disease (HHD). Up to 7 subjects will be administered topical KB111 to treat HHD lesions for 12 weeks. KB111 will be administered in the home setting by a trained designee. The Investigator (or designee) will contact subjects weekly (or their parent/legal guardian) to assess for any adverse events or changes in medications, treatments, or procedures. Preliminary efficacy will be assessed by investigator assessments, patient-reported impressions of severity and molecular analysis of skin biopsies. A safety follow-up visit will occur 4 weeks after treatment stops.
