Ritlecitinib demonstrated sustained clinical efficacy and an acceptable long-term safety profile in patients with alopecia areata and at least 25% scalp hair loss, according to results from a new study.

In the open-label phase III ALLEGRO-LT trial, published in the Journal of the European Academy of Dermatology and Venereology, researchers showed over a 24-month observation period that 73.5% of patients achieved a Severity of Alopecia Tool (SALT) score ≤ 20, and 66.4% achieved a SALT score ≤ 10. Additionally, 82.4% of the patients reported being "moderately" or "greatly improved," according to the Patient Global Impression of Change (PGI-C) scale.

The investigators enrolled 449 de novo patients aged 12 years or older with alopecia areata (AA) and at least 25% scalp hair loss. The patients received a daily 200-mg ritlecitinib loading dose for 4 weeks, followed by daily 50-mg doses thereafter. The mean exposure to ritlecitinib was 728.7 days.

Eyebrow and eyelash responses, defined as at least a 2-grade improvement or normalization from baseline for participants with abnormal baseline scores, were observed in 60.8% and 65.7% of the patients, respectively.

Overall, 86.1% of the patients reported treatment-emergent adverse events (TEAE), though most of them were classified as mild or moderate in severity. The most common TEAEs included positive SARS-CoV-2 tests (24.2%), headaches (20.8%), and pyrexia (13.0%).

Serious adverse events occurred in 4.9% of patients, with severe adverse events reported in 6.0%. Treatment discontinuations as a result of adverse events were observed in 6.5% of the patients. Notably, herpes zoster infections were identified in six patients, serious infections in four, malignancies (excluding nonmelanoma skin cancers) in three, and major adverse cardiovascular events in three.

"In patients with AA and ≥ 25% scalp hair loss, ritlecitinib demonstrated clinical efficacy and had an acceptable safety profile with long-term treatment," wrote C. Tziotzios, of the St. John's Institute of Dermatology at King's College in London.

The study underscored the therapeutic potential of ritlecitinib among patients with AA requiring long-term care and monitoring. Further investigation into the long-term safety outcomes remains warranted.

Full disclosures are detailed in the study.