Characterization of Scalp, Eyelash and Eyebrow Hair Regrowth in Patients with Severe Alopecia Areata Randomized to Placebo in Brave AA1 and Brave AA2 Trials

Abstract Background Alopecia areata (AA) is an auto‐immune disorder characterized by non‐scarring hair loss. With the emergence of effective therapies for severe AA, there is a need to better understand the prognosis of untreated AA, specifically the potential for spontaneous hair regrowth. Objectives To describe hair regrowth occurring on placebo during the first 36 weeks of the BRAVE‐AA trials. Methods This analysis pools the data of 345 placebo‐treated patients from BRAVE‐AA1 and BRAVE‐AA2, two Phase 3 clinical trials of baricitinib, an oral selective Janus kinase inhibitor, approved for the treatment of adults with severe AA. Scalp hair regrowth was assessed by the mean change from baseline in Severity of Alopecia Tool (SALT), the proportion of patients achieving a SALT score ≤20 (less than 20% hair loss); and SALT50 (50% improvement from baseline in SALT score), between Weeks 0 and 36. Patients achieving Clinician Reported Outcome (ClinRO) measures for eyebrow and eyelash hair loss™ scores of 0 or 1 (full coverage or minimal gaps) with a ≥2‐point improvement from baseline were also assessed. Results At Week 36, the mean [SD] change from baseline in SALT score was −5.5 [20.9], with 14 (4.1%) and 32 (9.3%) of the 345 placebo‐treated patients achieving a SALT score ≤20 and SALT50, respectively. A total of 9 (3.8%) and 8 (4.3%) patients achieved a ClinRO score of 0 or 1 with a ≥2‐point improvement from baseline for eyebrow (n = 236) and eyelash (n = 186), respectively. Patients achieving a SALT score ≤20 tended to have a lower mean SALT score at baseline and a shorter duration since the onset of AA. Conclusions The low likelihood of spontaneous hair regrowth observed in the BRAVE‐AA trials is consistent with other published literature. These results can aid in understanding the prognosis of severe AA when left untreated and, in turn, inform treatment‐related decisions.