Incyte Reports Positive Phase 3 Trial Results for Povorcitinib in Hidradenitis Suppurativa

WILMINGTON, Del.--(BUSINESS WIRE)--Mar. 17, 2025-- Incyte has recently revealed encouraging topline findings from their pivotal Phase 3 STOP-HS clinical trial, which investigates the safety and effectiveness of povorcitinib (INCB054707). Povorcitinib is an oral small-molecule JAK1 inhibitor developed for adult individuals aged 18 and above, suffering from moderate to severe hidradenitis suppurativa (HS).

The clinical trial program comprises two key studies, STOP-HS1 and STOP-HS2, both of which successfully reached their primary endpoints at the tested doses of 45 mg and 75 mg. A notably higher percentage of participants receiving povorcitinib once daily, compared to those given a placebo, achieved the Hidradenitis Suppurativa Clinical Response (HiSCR). This response is characterized by a 50% or greater reduction in the overall count of abscesses and inflammatory nodules without any increase in abscess or draining tunnel count from the baseline. Specifically, the proportion of patients on povorcitinib achieving HiSCR50 at Week 12 was significantly greater than those on placebo.

Among patients previously exposed to biologic treatments, povorcitinib showed increased efficacy, as indicated by HiSCR50, in comparison to placebo, with notable statistical significance. Additionally, by Week 12, more patients on povorcitinib reached deeper levels of clinical response, including HiSCR75 and a noticeable reduction in flare-ups. The treatment also resulted in a greater than 3-point decline in the Skin Pain Numeric Rating Scale (NRS) and improved Skin Pain NRS30 measurements. Importantly, povorcitinib demonstrated a swift onset of action, significantly alleviating skin pain rapidly.

The safety profile of povorcitinib was consistent with previous findings. There were no new safety concerns, and both doses were well-tolerated by patients.

Dr. Steven Stein, Chief Medical Officer of Incyte, commented on the findings by highlighting the challenging nature of hidradenitis suppurativa, which currently lacks a cure. He emphasized the urgent need for new treatments that are both effective and well-tolerated, capable of quickly reducing the signs and symptoms of HS, particularly in managing pain. The positive outcomes from the Phase 3 trial suggest povorcitinib holds promise as an oral treatment for HS patients.

These results will underpin a proposed regulatory submission for povorcitinib in treating HS on a global scale. Furthermore, the data from the STOP-HS trials are slated for presentation at forthcoming scientific gatherings.

The STOP-HS program consists of two Phase 3 studies, STOP-HS1 (NCT05620823) and STOP-HS2 (NCT05620836). These studies assess the efficacy and safety of povorcitinib in adult patients with moderate to severe HS. Both studies feature a 12-week double-blind, placebo-controlled treatment phase, followed by a 42-week extension period and a 30-day post-treatment safety follow-up.

Approximately 600 patients have been enrolled in each study. All participants are aged 18 or older and have been diagnosed with moderate to severe HS for a minimum of three months before screening. They meet specific criteria, including a total AN count of at least five, lesions across at least two different anatomical regions, and a documented history of inadequate response to at least a three-month course of conventional systemic therapy for HS, or a history of intolerance or contraindication to such treatments.

The primary goal for both studies is the proportion of patients achieving HiSCR50 by Week 12. Key secondary objectives include the proportion of patients attaining HiSCR75, the frequency of flare-ups over 12 weeks, the extent of pain reduction as measured by the Skin Pain NRS, and the evaluation of adverse events.

Hidradenitis suppurativa is a chronic inflammatory condition marked by painful nodules and abscesses, leading to tissue damage and scarring. It significantly impacts patients' quality of life. Povorcitinib, an oral JAK1 selective inhibitor, is undergoing Phase 3 trials for HS, vitiligo, and prurigo nodularis, as well as Phase 2 trials for other conditions such as asthma and chronic spontaneous urticaria, highlighting its potential broad utility.