Long-term safety and efficacy of ritlecitinib in adults and adolescents with alopecia areata and at least 25% scalp hair loss: Results from the ALLEGRO-LT phase 3, open-label study

BackgroundALLEGRO-LT is an ongoing, long-term, open-label, multicentre, phase 3 study of ritlecitinib in adults and adolescents with alopecia areata (AA).ObjectivesTo evaluate ritlecitinib safety and efficacy through Month 24 in patients with AA and >= 25% scalp hair loss.MethodsALLEGRO-LT enrolled rollover patients who previously received study intervention in either ALLEGRO phase 2a or 2b/3 studies and de novo patients who had not received treatment in either study. The de novo cohort results are reported here. Patients aged >= 12 years with AA and >= 25% scalp hair loss received a daily, 4-week 200-mg ritlecitinib loading dose, followed by daily 50-mg ritlecitinib. Analyses are based on data up to the cut-off (December 2022). Efficacy outcomes included proportions of patients achieving Severity of Alopecia Tool (SALT) scores <= 20 and <= 10, Patient Global Impression of Change (PGI-C) score of 'moderately improved' or 'greatly improved' and eyebrow assessment (EBA) and eyelash assessment (ELA) response (>= 2-grade improvement from baseline or normal score in patients with abnormal baseline EBA/ELA).ResultsMean (SD) ritlecitinib exposure among the 449 de novo patients enrolled was 728.7 (273.81) days. At Month 24 (as observed), 73.5% and 66.4% of patients achieved SALT score <= 20 and <= 10; 82.4% had PGI-C response; 60.8% and 65.7% had EBA and ELA response. 86.1% of patients reported treatment-emergent adverse events (AEs); most were mild or moderate in severity, with the most frequent being positive SARS-CoV-2 test (24.2%), headache (20.8%) and pyrexia (13.0%). Rates of serious AEs, severe AEs and treatment discontinuations were 4.9%, 6.0% and 6.5%, respectively. Herpes zoster infection occurred in six patients, serious infections in four, malignancies (excluding nonmelanoma skin cancer) in three and major adverse cardiovascular events in three.ConclusionsIn patients with AA and >= 25% scalp hair loss, ritlecitinib demonstrated clinical efficacy and had an acceptable safety profile with long-term treatment.Clinical Trial RegistrationClinicalTrials.gov NCT04006457.