MoonLake Reports Strong One-Year Phase 3 Results for Sonelokimab in Hidradenitis Suppurativa

MoonLake Immunotherapeutics has announced positive Week 52 results from its Phase 3 VELA-1 and VELA-2 clinical trials evaluating sonelokimab (SLK) in patients with moderate-to-severe hidradenitis suppurativa (HS).

The latest data showed that patients continued to improve throughout the one-year treatment period, with results building on the positive outcomes already seen at Week 16.

The VELA studies form the company’s global registrational program and are designed to support future regulatory submissions for sonelokimab in HS.

Strong Clinical Responses Continue Through One Year

At Week 52, 67.2% of patients treated with sonelokimab achieved HiSCR75, meaning they experienced at least a 75% reduction in inflammatory lesions associated with hidradenitis suppurativa.

In addition, 33.1% of patients achieved HiSCR100, indicating complete clearance of inflammatory lesions.

The results remained consistent across both Phase 3 studies.

In VELA-1, 68.3% of patients achieved HiSCR75 and 31.2% achieved HiSCR100.

In VELA-2, 66.0% achieved HiSCR75 while 35.1% reached HiSCR100.

These findings suggest that sonelokimab continued to provide durable disease control over a full year of treatment.

Significant Number of Patients Reached Inflammatory Remission

MoonLake also reported encouraging results using the International Hidradenitis Suppurativa Severity Score System (IHS4).

At Week 52, 26% of patients achieved an IHS4-100 response, a measure that reflects inflammatory remission.

This outcome represents complete elimination of abscesses, inflammatory nodules, and draining tunnels.

According to the company, the long-term outcomes from the VELA program compared favorably with results reported in previous Phase 3 studies involving competing therapies for hidradenitis suppurativa.

Improvements Extended Beyond Skin Lesions

The company highlighted that the benefits of sonelokimab were not limited to clinical lesion reduction.

Patients also reported meaningful improvements in daily quality of life and symptom burden.

One of the most important measures was the Hidradenitis Suppurativa Quality of Life (HiSQOL) score.

Patients receiving sonelokimab experienced substantial improvements in quality of life at Week 52.

In VELA-1, the average HiSQOL score improved by 15.3 points from baseline, while VELA-2 showed an improvement of 14.8 points.

Pain reduction was another notable outcome. Nearly half of treated patients experienced a clinically meaningful reduction in skin pain, measured as at least a three-point improvement from baseline.

Placebo Patients Also Improved After Switching to Sonelokimab

The studies included patients who initially received placebo and later crossed over to sonelokimab treatment at Week 16.

After just four weeks of sonelokimab therapy, these patients experienced a rapid improvement in response rates.

HiSCR75 rates increased by approximately 20 percentage points across both studies, providing additional support for the treatment's effectiveness.

High Treatment Acceptance and Convenient Dosing

MoonLake reported a high continuation rate across the VELA clinical program.

Approximately 90% of patients chose to continue into the VELA-OLE study, a two-year open-label extension trial designed to evaluate long-term outcomes.

The company believes this strong participation reflects both the effectiveness and tolerability of sonelokimab, as well as the convenience of its once-every-four-weeks dosing schedule.

The treatment is administered at a dose of 120 mg every four weeks.

Positive Results Also Seen in Adolescent Patients

In addition to adult studies, MoonLake shared interim data from the VELA-TEEN clinical trial, which evaluates sonelokimab in adolescents with hidradenitis suppurativa.

The Week 24 analysis showed encouraging response rates among younger patients.

Approximately 68% achieved HiSCR75, while around 86% achieved HiSCR50.

Nearly 45% of adolescent patients achieved HiSCR100, indicating complete clearance of inflammatory lesions.

The company noted that response rates in adolescents were even higher than those seen in adults at comparable time points, suggesting the potential benefits of treating the disease earlier in its course.

Safety Profile Remains Consistent

Across the VELA program and the VELA-TEEN study, sonelokimab maintained a consistent safety profile.

MoonLake reported that no new safety signals were identified during the studies.

The treatment continued to demonstrate good tolerability over the one-year evaluation period, supporting its potential use as a long-term therapy for patients with hidradenitis suppurativa.

Company Highlights Potential for Best-in-Class Therapy

Commenting on the results, MoonLake Chief Executive Officer Dr. Jorge Santos da Silva said the Week 52 findings reinforce the strength of sonelokimab across key measures that matter to patients and physicians.

He noted that the treatment demonstrated strong early efficacy, durable long-term improvement, a favorable safety profile, and convenient dosing in both adults and adolescents.

Chief Scientific Officer Prof. Kristian Reich added that the consistency between clinical outcomes and patient-reported benefits is particularly important in hidradenitis suppurativa, where disease burden extends far beyond visible skin lesions.

According to MoonLake, the data support the potential of sonelokimab to deliver long-term disease control while improving patients' quality of life.

Regulatory Submission Planned for September 2026

MoonLake has confirmed plans to submit a Biologics License Application (BLA) for sonelokimab in hidradenitis suppurativa to the U.S. Food and Drug Administration (FDA) by the end of September 2026.

The company stated that the pre-BLA process has already been completed and no additional regulatory meetings with the FDA are currently planned.

MoonLake expects to receive clarity on the Prescription Drug User Fee Act (PDUFA) date by the end of November 2026 when the FDA decides whether to accept the application for review.

The company also intends to request Priority Review status based on the treatment’s clinical profile and supportive adolescent data.

If Priority Review is granted, the FDA review timeline could be shortened by approximately one quarter. If not granted, MoonLake expects a potential commercial launch for sonelokimab during the third or fourth quarter of 2027.