Sonelokimab Demonstrates High HiSCR100 Rates and Durable Responses in Hidradenitis Suppurativa

“If you don’t get the inflammatory lesions under control early on, they progress to irreversible tissue damage. We should be maximally motivated to get the inflammation under control as early as possible,” said Kristian Reich, MD, PhD, at the 2026 American Academy of Dermatology Annual Meeting in Denver, Colorado.

Reich, a dermatologist and the founder and chief scientific officer of MoonLake Immunotherapeutics, and Christopher Bunick, MD, PhD, associate professor of dermatology at Yale School of Medicine and Dermatology Times’ editor in chief, discussed emerging long-term data presented for sonelokimab, an investigational nanobody from MoonLake Immunotherapeutics, for the treatment of moderate to severe hidradenitis suppurativa (HS).^1,2

Data Overview

Reich first previewed late-breaking data highlighting durability of response beyond traditional primary endpoints. “We always look at week 12, week 16…for regulatory purposes. But having treated chronic inflammatory diseases, what really matters is the long-term benefit and risk profile,” he said. The dataset includes more than 800 patients across 2 trials, with outcomes reported through approximately week 40 to 50.

Clinically, the efficacy signals appear notable relative to existing benchmarks in HS. Reich reported HiSCR75 response rates exceeding 60%, with approximately 30% of patients achieving HiSCR100. Importantly, about 25% of patients reached what he termed “inflammatory remission”—“no nodule, no abscess, no draining tunnel.” He emphasized that this level of clearance addresses a critical unmet need, particularly given the disproportionate burden of abscesses and draining tunnels on patient quality of life—features not fully captured in conventional HiSCR endpoints.

Mechanistically, sonelokimab represents a novel class of nanobody-based therapeutics. Reich described it as a trivalent construct targeting both IL-17A and IL-17F, with an additional albumin-binding domain to extend half-life and enhance tissue localization. “It blocks IL-17A, it blocks IL-17F…[and] does it differently than the antibodies that are available,” he noted. At approximately 40 kDa, the molecule is significantly smaller than conventional monoclonal antibodies, which may facilitate improved tissue penetration, particularly in fibrotic or tunnel-rich HS lesions. He also highlighted its propensity to localize to inflamed tissue via albumin binding, a feature that may enhance drug concentration at sites of disease activity.

Bunick noted the potential clinical implications, particularly the possibility of redefining therapeutic goals in HS. “We really haven’t been talking about HiSCR90 or HiSCR100,” he said, noting that these higher thresholds could represent a shift in expectations if consistently achievable.

Reich contextualized these findings within the broader treatment gap in HS, citing that fewer than 4% of the approximately 2.5 million diagnosed patients in the US receive biologic therapy. “We should be maximally motivated to get the inflammation under control as early as possible,” he emphasized, given the risk of progression to irreversible scarring and tunnel formation.

Collectively, the data position sonelokimab as a potentially differentiated IL-17–targeting therapy with the capacity to address multiple HS lesion types and raise the bar for clinical response, particularly in achieving deep remission across inflammatory phenotypes.

References

1. MoonLake announces week 40 results from its phase 3 clinical trials of sonelokimab in hidradenitis suppurativa at the 2026 AAD Annual Meeting. News release. MoonLake Immunotherapeutics. March 28, 2026. Accessed March 28, 2026. https://ir.moonlaketx.com/news-releases/news-release-details/moonlake-announces-week-40-results-its-phase-3-clinical-trials
2. Kimball A. Sonelokimab in moderate-to-severe HS: long-term results through week 40 of two phase 3 trials. Presented at: 2026 American Academy of Dermatology Annual Meeting; March 27-31, 2026; Denver, CO.