Oruka Therapeutics Inc. (NASDAQ:ORKA) saw its shares surge 45% after releasing encouraging Week 16 data from its ongoing EVERLAST-A Phase 2a study in patients with moderate-to-severe plaque psoriasis.
The trial met its primary objective, with 63.5% of patients treated with ORKA-001 achieving PASI 100 at Week 16, indicating complete skin clearance. An identical proportion also reached IGA 0, reflecting fully clear skin with no visible signs of the disease.
EVERLAST-A is a randomized, double-blind, placebo-controlled Phase 2a study assessing ORKA-001, a next-generation IL-23p19 monoclonal antibody designed with an extended half-life. The trial enrolled 84 patients across 26 sites in the United States and Canada, with participants assigned in a 3:1 ratio to receive 600 mg of ORKA-001 at Week 0 and Week 4 or a matching placebo.
Secondary endpoints were also strong, with 83% of treated patients achieving PASI 90 at Week 16 and 84% reaching IGA 0/1. By contrast, only one of the 21 participants in the placebo group met these benchmarks. All response rates were calculated using non-responder imputation.
The treatment demonstrated a safety profile consistent with other IL-23p19 therapies. No serious treatment-related adverse events were reported, and the only severe adverse event occurred in the placebo group. Overall adverse event rates were similar between groups, affecting 51% of ORKA-001 patients and 57% of those receiving placebo. The most frequently reported issue was upper respiratory tract infection, seen in 19% of treated patients compared with 14% in the placebo group.
The company added that updated Phase 1 pharmacokinetic and pharmacodynamic data continue to support the potential for once-yearly dosing. Additional long-term results from the EVERLAST-A study are expected in the second half of 2026.