Positive Results for JAK1 Inhibitor Povorcitinib Reported in Late Breaker | AAD 2024

An investigational Janus kinase (JAK)1 inhibitor produced positive results in phase 2 trial for prurigo nodularis, according to a presentation at the annual meeting of the American Academy of Dermatology (AAD), which was held in San Diego this weekend.

The investigational, povorcitinib, an oral small-molecule drug, is in late-stage clinical trials as a treatment for number of dermatological conditions, including hidradenitis suppurativa, vitiligo and chronic spontaneous urticaria.

Prurigo nodularis is relatively rare (less than 100 cases per 100,000 population) that tends to affect older adults and is characterizes by itchy nodules (firm bumps) on the skin. It occurs with chronic pruritis and is often seen in people with a history of atopic dermatitis.

The positive results were from a double-blind, placebo-controlled phase 2 clinical trial that enrolled 146 adult patients who had not responded to other treatments for prurigo nodularis or had side effects that meant they stopped being treated. The primary endpoint was a marked improvement (four points or great) on a standard scale for measuring itch (the 11-point Itch Numerical Rating Scale) over 16 weeks. The trial was sponsored by the drug’s maker, Incyte Corporation, a biopharmaceutical company headquartered in Wilmington, Delaware.

The results, which were presented Sunday afternoon at the second of the AAD meeting’s late-breaking abstract sessions, showed that as the povorcitinib dose increases, so did the number of study participants who reached the primary endpoint, according to a company news release. At a 15 milligram (mg) dose, 36%of the study participants reached the primary endpoint; at a 45-mg dose, 44% did; and 75 mg, 54% crossed the pre-designated threshold. In contrast, 8% of the patients in the placebo had marked improvement on the itch scale.

The safety profile of povorcitinib that emerges from the data of this trial was consistent with previous reported data, according to the news release. The most common treatment-emergent adverse events (TEAEs) were headache (11.1%), fatigue (9.3%) and nasopharyngitis (7.4%), the news release says. TEAEs graded as serious occurred in nine (8.3%) of the study participants randomized to be treated with povorcitinib and four patients in the treatment group dropped out of the 16-week study because of adverse events compared with one in the placebo group.

“These Phase 2 results, particularly the demonstrated improvement in itch resolution after just four weeks of treatment, are promising for patients around the world living with this disease. We are excited to be expanding research on povorcitinib into this new potential indication,” Kurt Brown, M.D., vice president and povorcitinib global program head at Incyte, said in the news release.

“Breaking the itch-scratch cycle is imperative when treating patients with PN [prurigo nodularis], and I’m encouraged by these results illustrating improvement in itch and also skin clearance by Week 16 which shows promise for povorcitinib as a potential novel treatment option for these patients,” Martin Metz, M.D., professor of dermatology and allergy at Charité–Universitätsmedizin, Berlin in Germany, said in the news release. Metz was listed as the presenter of the results at the AAD late-breakers session.

Based on these and other results, Incyte is planning a phase 3 trial of povorcitinib as a treatment for prurigo nodularis.

Incyte has pioneered the developed of JAK inhibitors. It makes and markets Jakafi (ruxolitinib), which was first JAK inhibitor approved by the FDA. Incyte also makes and markets Opzelura (ruxolitinib), a topical JAK inhibitor that has been approved as treatment for atopic dermatitis and vitiligo. Incyte has reported that Opzelura generated $338 million in net revenues for the company last year.

JAK inhibition has become one of the most fruitful mechanisms of action in dermatology. In addition to Opzelura, the JAK inhibitors approved by the FDA and currently on the market include Rinvoq (upadacitinib) and Cibinquo (abrocitinib), once-daily oral tablets for treatment of moderate-to-severe atopic dermatitis, and Olumiant (baricitinib), a once-daily tablet for severe alopecia areata.