Nanobody sonelokimab - (IZAR-1)

August 10, 2026: MoonLake Immunotherapeutics (NASDAQ: MLTX) reported positive topline Week 16 results from the Phase 3 IZAR-1 trial of sonelokimab in biologic-naïve adults with active psoriatic arthritis. The 60 mg with induction arm met the primary endpoint and all clinical endpoints disclosed under the FDA-agreed unblinding protocol: ACR50 42.1%, ACR20 66.5%, minimal disease activity 41.2%, and PASI90 61% in patients with skin involvement. Mean HAQ-DI change was -0.427 and SF-36 PCS improved by 6.54. The blinded safety review was consistent with prior studies, with no new safety signals reported and a low Week 16 dropout rate.

IZAR-1 remains blinded through Week 52, with the full readout expected in H1 2027. IZAR-2, the companion Phase 3 trial in TNF-refractory patients, is expected to complete enrollment in Q3 2026 and includes a risankizumab active reference arm.

Other upcoming milestones cited: expected HS BLA submission by end-September 2026; expected PDUFA date allocation and Priority Review decision by end-November 2026; PPP enrollment start in H2 2026; and P-OLARIS results in PsA/axSpA at end-2026 or early 2027.

MoonLake ended Q2 2026 with $537.0 million in cash and marketable securities, with runway to mid-2028.