Povorcitinib Demonstrates Promising Phase 3 Results for Hidradenitis Suppurativa Treatment

Hidradenitis suppurativa of axilla | Image Credit: © DermNet

Incyte announced today positive topline results from its phase 3 STOP-HS clinical trial program evaluating povorcitinib (INCB054707), a JAK1 inhibitor, for moderate to severe hidradenitis suppurativa (HS).¹

The trials, STOP-HS1 (NCT05620823) and STOP-HS2 (NCT05620836), met primary efficacy endpoints with a statistically significant proportion of patients achieving the Hidradenitis Suppurativa Clinical Response (HiSCR50) compared to placebo.

Efficacy Outcomes

The phase 3 trials assessed povorcitinib at 45 mg and 75 mg once daily over a 12-week period. The primary endpoint, HiSCR50, defined as a ≥50% reduction from baseline in total abscess and inflammatory nodule (AN) count with no increase in abscesses or draining tunnels, was achieved at both doses.

In the STOP-HS1 trial, the 45 mg dose demonstrated a response rate of 40.2% compared to 29.7% in the placebo group (P=0.024), while the 75 mg dose showed a similar response rate of 40.6% versus 29.7% for placebo (P=0.022).

In the STOP-HS2 trial, both the 45 mg and 75 mg doses achieved a response rate of 42.3%, significantly outperforming the placebo group, which had a response rate of 28.6% (P=0.004 and P=0.003, respectively).

Patients with prior biologic exposure showed even greater differential efficacy, particularly in STOP-HS2, where HiSCR50 rates reached 45% at 45 mg and 40% at 75 mg, compared to 19.5% in the placebo group.

Additionally, significant secondary outcomes were observed, including achievement of HiSCR75, indicating a 75% reduction in AN count. Patients also experienced a reduction in HS-related flare-ups, a ≥3-point improvement in the Skin Pain Numeric Rating Scale, and a rapid onset of pain relief.

Safety Profile

The safety data from STOP-HS1 and STOP-HS2 align with prior findings, with povorcitinib demonstrating a favorable tolerance profile. No new safety signals emerged.

Clinical Implications

Povorcitinib’s positive phase 3 results suggest it could offer a new, effective systemic therapy for HS patients, particularly those with prior treatment failure.¹

These findings are expected to support global regulatory submissions. Full data will be presented at upcoming scientific meetings.

References

1. Incyte announces positive topline results from two phase 3 clinical trials of povorcitinib in patients with hidradenitis suppurativa. News release. March 17, 2025. Accessed March 17, 2025. https://www.businesswire.com/news/home/20250317947508/en/Incyte-Announces-Positive-Topline-Results-From-Two-Phase-3-Clinical-Trials-of-Povorcitinib-in-Patients-With-Hidradenitis-Suppurativa
2. A study of povorcitinib in hidradenitis suppurativa (STOP-HS1). ClinicalTrials.gov. Identifier: NCT05620823. Accessed March 17, 2025. https://clinicaltrials.gov/study/NCT05620823
3. A study of povorcitinib in hidradenitis suppurativa (STOP-HS2). ClinicalTrials.gov. Identifier: NCT05620836. Accessed March 17, 2025. https://clinicaltrials.gov/study/NCT05620836