MoonLake announces landmark Phase 2 results for Nanobody sonelokimab

MoonLake Immunotherapeutics announced positive top-line results from its global Phase 2 ARGO trial evaluating the efficacy and safety of the Nanobody sonelokimab in patients with active psoriatic arthritis. The ARGO trial, which enrolled 207 patients, met its primary endpoint with a statistically significant greater proportion of patients treated with either sonelokimab 60mg or 120mg achieving an American College of Rheumatology 50 response compared to those on placebo at week 12. Specifically, for the 60mg and 120mg doses with induction, respectively, 46% and 47% of patients treated with sonelokimab achieved ACR50; 78% and 72% of patients achieved ACR20; and 29% and 26% achieved ACR70. The primary analyses were based on the most stringent type of analysis for such trials, intention-to-treat with non-responder imputation. As expected, the 60mg dose without induction did not reach statistical significance, confirming the 60mg and 120mg with induction as the potential dose regimens to carry forward into Phase 3. All key secondary endpoints were met for the 60mg and 120mg doses with induction. The key secondary endpoint Psoriasis Area and Severity Index 90 was met for all doses with induction; 77% of patients responding at week 12 to the 60mg dose. For this dose, 58% of patients achieved complete skin clearance at week 12. PASI responses across dose arms were consistent with the previously reported Phase 2b data of sonelokimab in moderate-to-severe plaque-type psoriasis, with the 120mg dose achieving the highest responses for PASI100 in patients with more severe skin lesions. Other clinically relevant secondary endpoints, such as Minimal Disease Activity, the modified Nail Psoriasis Severity Index, the Leeds Enthesitis Index and the patient self-reported Psoriatic Arthritis Impact of Disease, each show promising levels of response at week 12. Adalimumab was used as an active reference to validate responses across arms. Sonelokimab 60mg and 120mg numerically outperformed adalimumab on the primary endpoint and all key secondary endpoints, with the observed deltas further supporting the potential for sonelokimab as a future leading therapy. The patient discontinuation rate in the ARGO trial was low at week 12, similar to what was observed in previous trials of sonelokimab in psoriasis and hidradenitis suppurativa. The safety profile of sonelokimab in ARGO was consistent with previously reported studies with no new safety signals. The results suggest that, as early as week 12, the Nanobody sonelokimab reaches levels of clinical response at or above those seen with other therapies tested in similarly stringent trials. The high performance of sonelokimab and its favorable safety profile continue to support the potential of using a smaller biologic with albumin-binding capacity to inhibit IL-17A and IL-17F for the treatment of inflammatory diseases.