Phase 3 Findings on Long-Term Ritlecitinib in Adults, Adolescents with Alopecia Areata

New phase 3 findings from the ongoing ALLEGRO-LT study suggest that ritlecitinib 50 mg is effective as a long-term treatment in adults and adolescents aged 12 years and older living with alopecia areata.1

These findings resulted from a study titled ‘Long-Term Efficacy and Safety of Ritlecitinib in Adults and Adolescents with Alopecia Areata (AA): 3-Year Results from the ALLEGRO-LT Phase 3, Open-Label Study.’ The data was presented as a poster at the Dermatology Education Foundation (DERM) 2025 NP/PA CME Conference in Las Vegas, Nevada.

This study was authored by a team of investigators such as Maryanne Makredes Senna, MD, a board-certified dermatologist for Beth Israel Lahey Health and an assistant professor of dermatology at Harvard Medical School. Senna and colleagues highlighted in their study’s background information that alopecia areata is an autoimmune disease that often leads to patchy or complete non-scarring hair loss.

This hair loss can be seen on the scalp and is often accompanied by additional loss of facial or body hair. Senna and coauthors set out to evaluate the efficacy and safety of ritlecitinib up to 3 years in individuals with alopecia areata, highlightling prior data from the ALLEGRO-2b/3 study as well as their ongoing, phase 3, open-label ALLEGRO-LT analysis.1,2

Ritlecitinib is a selective dual Janus kinase 3 (JAK3)/tyrosine kinase expressed in hepatocellular carcinoma (TEC) kinase family inhibitor. During the ALLEGRO-2b/3 analysis, patients recruited for the study were aged ≥12 years and had a diagnosis of alopecia areata with ≥50% scalp hair loss. The loss of their hair could be due to alopecia totalis as well as alopecia universalis.

The maximum duration of the current episode of hair loss among these potential trial subjects was required to be ≤10 years. These individuals were treated with ritlecitinib 50 mg on a once-daily basis during the ALLEGRO-2b/3 study and would continue the same dosage in the ongoing ALLEGRO-LT analysis.

Adolescents included in ALLEGRO-LT were required by Senna et al to have an improvement in their Severity of Alopecia Tool (SALT) score of ≥50% from baseline by the 3-month mark in ALLEGRO-2b/3 and a SALT score of ≤20 by the 6-month mark to continue in the ALLEGRO-LT analysis. ALLEGRO-LT recruited rollover patients who had previously been given treatment either in the ALLEGRO phase 2a or 2b/3 studies and recruited de novo patients who had not been given the treatment in either analysis.

By 24 months, 73.5% and 66.4% of those involved attained SALT scores ≤20 and ≤10, respectively. Overall, Senna and coauthors concluded that ritlecitinib 50 mg treatment among patients with alopecia areata demonstrated meaningful clinician- and patient-reported efficacy.

86.1% of those assessed in ALLEGRO-LT were found to have reported treatment-emergent adverse events (AEs), although most were noted by the investigators as being mild or moderate in severity. They concluded that the most frequent AEs were positive SARS-CoV-2 test in 24.2%, headaches in 20.8%, and pyrexia in 13.0%.

Rates of serious AEs, severe AEs, and discontinuations of ritlecitinib were shown by Senna and colleagues to be 4.9%, 6.0% and 6.5%, respectively. The newly-presented findings from this ongoing study were also noted to be the longest duration of ritlecitinib therapy to be reported to date. The findings support the long-term implementation of ritlecitinib in patients in the age range of ≥12 years with alopecia areata.

For any additional information on related data highlighted at DERM 2025, view our latest conference coverage here.

References

1. Senna M, Figueras I, Tran H, et al. Long-Term Efficacy and Safety of Ritlecitinib in Adults and Adolescents with Alopecia Areata (AA): 3-Year Results from the ALLEGRO-LT Phase 3, Open-Label Study. Poster presented at the DERM 2025 NP/PA CME Conference; July 23 - 26, 2025; Las Vegas, Nevada.

2. Sinclair R, Mesinkovska N, Mitra D, King B, et al. Patient-Reported Hair Loss and Its Impacts as Measured by the Alopecia Areata Patient Priority Outcomes Instrument in Patients Treated with Ritlecitinib: The ALLEGRO Phase 2b/3 Randomized Clinical Trial. Am J Clin Dermatol. 2025 Jan;26(1):109-119. doi: 10.1007/s40257-024-00899-4. Epub 2024 Oct 23. PMID: 39441519; PMCID: PMC11742000.