Four top alopecia experts tell DermWire what the approval of Litfulo (ritlecitinib) will mean for patients.

The US Food and Drug Administration (FDA) approved Litfulo (ritlecitinib, Pfizer Inc) for severe alopecia areata in individuals 12 years of age and older.

A kinase inhibitor that targets Janus kinase 3 (JAK3) and the tyrosine kinase expressed in the hepatocellular carcinoma (TEC) family of kinases, Litfulo is the first and only FDA-approved treatment for adolescents (12+ years old) with severe alopecia areata. Litfulo joins Olumiant (baricitinib), a JAK inhibitor, from Eli Lilly and Company, which scored FDA approval for alopecia in 2022.

"Alopecia areata can be devastating at any age, but adolescence is often a particularly vulnerable time, so it is an incredible milestone to finally have an FDA-approved treatment option for patients as young as age 12," says Brittany Craiglow, MD, an associate professor adjunct – dermatology at Yale School of Medicine in New Haven, Conn., in an interview with DermWire. "We are learning that earlier intervention often yields better outcomes for patients with severe alopecia areata, so it is critical to have an effective treatment option for these younger patients who otherwise might have lost their window of opportunity for hair regrowth."

Ritlecitinib and baricitinib arhave comparable effectiveness and similar, favorable, safety profiles, says Brett King, MD, PhD. He is an associate professor of dermatology at Yale University in New Haven, Conn. who  pioneered the use of JAK inhibitors. "What separates them, at least right now, is that ritlecitinib is approved in people 12 years and older (for both adolescents and adults) while baricitinib is, for now, approved only in adults," he tells DermWire. "Time will tell if there turns out to be meaningful differences between the medicines — for instance, one works better in certain people than the other one and vice versa — that will influence the way we use them."

Arash Mostaghimi, MD, MPH, agrees. He is the director of the Dermatology Inpatient Service and the codirector of the Complex Medical Dermatology Fellowship Program at Brigham & Women's Hospital in Boston. "Although it is a JAK inhibitor, the JAK-3/TEC mechanism differentiates from baricitinib, which inhibits JAK 1 and 2," he tells DermWire. "Although future studies, including head-to-head comparisons, are critical, these different targets suggest that ritlecitinib may work in patients who do not have a sufficient response to baricitinib and vice versa."

Nicole Friedland, president and chief executive officer of the National Alopecia Areata Foundation (NAAF), also welcomes the new option. "The announcement of Litfulo's approval by the FDA is extremely significant not only because it is the second approved treatment for alopecia areata, but the first approved for adolescents," she tells DermWire. "As an alopecia areata diagnosis often occurs during childhood, the importance of an approved treatment for adolescents cannot be overstated. NAAF remains committed to supporting more breakthroughs and empowering our community with more choices."

Litfulo will be available in the coming weeks. The recommended dose for Litfulo is 50 mg. 

The FDA approval is based on clinical trial results, including the ALLEGRO phase 2b/3 trial. The trial, which enrolled 718 patients with 50% or more scalp hair loss as measured by the Severity of Alopecia Tool (SALT), evaluated the efficacy and safety of Litfulo at 118 sites in 18 countries. In this  study, 23% of patients treated with Litfulo 50 mg had 80% or more scalp hair coverage (SALT≤20) after 6 months compared to 1.6% with placebo. 

The efficacy and safety of Litfulo were consistent across adolescents and adults. Common adverse events include headache, diarrhea, acne, rash, and urticaria.