Medication information for patients: How effective is ritixitinib?

Ritlecitinib (Ritlecitinib) is a once-daily oral prescription medication indicated to improve hair loss in adults and adolescents 12 years of age and older with severe alopecia areata. Ritexitinib targets and selectively blocks specific proteins associated with hair loss, called Janus kinase 3 (JAK3) and TEC kinase, which play important roles in inflammation. This reduces the number of inflammatory cells that attack the hair follicles, allowing hair to regrow. Within 6 months, nearly a quarter of people taking ritexitinib experienced at least 80% hair regrowth, compared with 1.6% of those taking a placebo.

Rituxitinib 50 mg daily was significantly more effective than placebo (an inactive treatment) for scalp hair regrowth in patients with alopecia, with 23% achieving a SALT score of 20 or lower at 24 weeks. By week 48, 43.2% had achieved a salt score of 20 points or less. Significant eyelash and eyebrow regrowth also occurred. Evidence that ritixitinib is effective for hair loss comes from the ALLEGRO 2b/3 trial, which initially followed 718 adolescents and adults with alopecia totalis or generalized for 24 weeks and extended to 48 weeks and beyond.

Alopecia is based on the Hair Loss Severity Tool (SALT), which assesses the proportion of scalp surface affected by hair loss, where a SALT score of 0 indicates no hair loss and a SALT score of 100 indicates 100% hair loss. All participants had SALT scores greater than 50, indicating severe hair loss. 46% had a SALT score of 100.

After 24 weeks, 23% of people taking rituxitinib 50 mg reported a SALT score of 20 or lower, which was significantly more effective than those taking a placebo, an inactive pill. By week 48, 43.2% of trial participants taking ritexitinib 50 mg reported a SALT score of 20. This response rate continued to improve for up to 2 years. Additionally, people using ritexitinib had more eyebrow and eyelash regrowth compared to placebo. In 82% of people taking ritexitinib 50 mg for up to 48 weeks.