Pfizer says Phase 3 LITFULO trials met key vitiligo endpoints; plans global regulatory filings

Pfizer said Thursday that its Phase 3 vitiligo program for LITFULO, also known as ritlecitinib, met key endpoints, putting the drug on track for regulatory filings as a potential new oral systemic treatment for adults with nonsegmental vitiligo.

The update matters because treatment options for vitiligo remain limited, especially beyond creams and light-based therapies. In the United States, topical ruxolitinib cream, sold as Opzelura, is the main specifically approved repigmentation drug for patients 12 and older. Pfizer’s program is notable both for its late-stage status and its scale, with more than 2,100 patients studied globally.

The topline results, announced July 30, came from two pivotal trials, TRANQUILLO and TRANQUILLO 2, as well as a long-term extension study called TRANQUILLO LTE. Across the two main studies, Pfizer said 2,174 patients were evaluated at 271 sites worldwide.

TRANQUILLO enrolled 607 adults and adolescents ages 12 and older and tested LITFULO at 50 milligrams once daily. TRANQUILLO 2 enrolled 1,567 adults and tested 50 mg or 100 mg once daily. In both trials, the U.S. co-primary endpoints were measured at Week 52 and focused on facial and whole-body repigmentation: F-VASI75, meaning at least a 75% improvement from baseline in facial Vitiligo Area Scoring Index, and T-VASI50, meaning at least a 50% improvement from baseline in total-body Vitiligo Area Scoring Index.

Pfizer said the studies showed “significant, clinically meaningful improvements” versus placebo on those co-primary endpoints. But the company did not release detailed numerical efficacy data in its press release, such as response rates, p-values or confidence intervals, and it did not provide full safety-event counts. That means the strength of the benefit and the detailed safety profile cannot yet be independently assessed from the topline disclosure alone.

Nonsegmental vitiligo is an autoimmune condition in which the body attacks pigment-producing cells called melanocytes, leading to white patches on the skin, often on visible areas such as the face and hands. The condition is not life-threatening, but it can carry a major emotional and social burden for patients. Against that backdrop, a systemic oral option would represent an important new approach if regulators clear it.

LITFULO is an oral inhibitor of JAK3 and TEC family kinases, and Pfizer said it is being studied in vitiligo by targeting immune pathways involved in melanocyte destruction. The drug is already approved in multiple jurisdictions for severe alopecia areata in adults and adolescents 12 and older, including in the United States, European Union, Canada, Japan, China and the United Kingdom.

Any expansion into vitiligo, however, is likely to draw close scrutiny because LITFULO belongs to the broader JAK inhibitor class, which has faced regulatory attention over safety risks. Pfizer’s existing LITFULO safety information includes warnings about serious infections, shingles and some cancers, along with broader class-level concerns regulators have tied to JAK inhibitors. Those issues can weigh heavily in diseases such as vitiligo, where the condition can be deeply disruptive but is not fatal.

Based on the Phase 3 results, Pfizer said it intends to submit global regulatory filings for LITFULO as a potential treatment for adults with nonsegmental vitiligo. “These findings give us confidence that, if approved, LITFULO could become a new oral systemic treatment option for adults living with NSV,” Michael Vincent, Pfizer’s chief inflammation and immunology officer, said in the company’s press release.