This Phase 2 first-in-neonate EDI200 study will enroll treatment-naïve, XLHED-affected male newborns in the first two weeks of life. All subjects will meet entry criteria including documentation of an EDA mutation associated with XLHED. Following Baseline evaluations, EDI200 dosing will be initiated between day-of-life 2 and 14, with each study subject receiving 2 doses/week for a total of 5 doses. This dosing regimen mirrors that used to enhance efficacy in the dog XLHED model, considered to be most relevant to the clinical study design. The study will enroll subjects in two cohorts with subjects in cohort 1 dosed at 3 mg/kg/dose, associated with partial efficacy, and cohort 2 dosed at 10 mg/kg/dose where enhanced efficacy was demonstrated in the most relevant preclinical model. Given the challenge of identifying families where the subject is yet to be born, it is expected that cohort size and time for recruitment will be variable. The sponsor anticipates enrollment and dosing of 6-10 subjects over a 12-18 month period, 3-5 subjects per cohort.
