Week 28 results from its EVERLAST-A Phase 2a trial of ORKA-001, a novel half-life extended IL-23p19 monoclonal antibody, in moderate-to-severe plaque psoriasis.

"These Week 28 results, with responses continuing to deepen months after the last dose, point to the incredible potential of ORKA-001," said Joana Goncalves, MBChB, Chief Medical Officer of Oruka. "With over 70% of patients achieving completely clear skin after just two induction doses and a safety profile consistent with the IL-23 class, ORKA-001 has the potential to redefine the standard of care for psoriasis. We look forward to sharing the full 52-week data later this year."

"The depth of clearance seen at Week 28, achieved without any dosing beyond Week 4, is remarkable," said Bruce Strober, MD, PhD, Clinical Professor of Dermatology at Yale University School of Medicine and lead investigator for EVERLAST-A. "To see PASI 100 rates continue to climb over time speaks to the potential of this molecule. The emerging profile of ORKA-001 could offer patients substantial disease control along with very infrequent dosing."

EVERLAST-A is a randomized, double-blind, placebo-controlled Phase 2a trial evaluating the safety, efficacy, and pharmacokinetics of ORKA-001 in patients with moderate-to-severe plaque psoriasis. The study is being conducted across 26 sites in the United States and Canada and enrolled 84 patients randomized 3:1 to receive 600 mg of ORKA-001 at Week 0 and 4 or matching placebo. Patients who initially received placebo received 600 mg of ORKA-001 at Week 16 and 20. The study continues through Week 52 to assess durability of response, maintenance dosing, and long-term safety.

Efficacy

As previously reported, 63.5% of patients (40 of 63) treated with ORKA-001 achieved the primary endpoint of PASI 100 at Week 16. Clinical responses continued to deepen through Week 28, six months after the last dose of ORKA-001. PASI 100 response rates increased to 71.4% (45 of 63) and PASI 90 response rates increased to 87.3% (55 of 63) at Week 28. IGA 0/1 response rates were maintained at 84.1% (53 of 63).

Patients who initially received placebo and crossed over blinded to ORKA-001 at Week 16 demonstrated a similar pattern of clinical response to those initially receiving ORKA-001. In this dosing arm, 40.0% (8 of 20) achieved PASI 100 at Week 28 (12 weeks after dosing) compared to 42.9% (27 of 63) of patients in the active arm at the equivalent timepoint.

Safety

ORKA-001 continues to be well tolerated, with a safety profile consistent with the IL-23p19 class. Between Weeks 16-28, the only treatment-emergent adverse event in ≥5% of patients receiving ORKA-001 was upper respiratory tract infection, occurring in 8% (7 of 83) of patients. Two patients experienced serious adverse events, neither deemed drug related: one tibial fracture and one case of prostate adenocarcinoma in a patient with elevated prostate-specific antigen (PSA) at baseline. There continue to be no injection site reactions. No impact of anti-drug antibodies on safety, efficacy, or PK has been observed.

Upcoming Milestones for ORKA-001

Oruka plans to share longer-term data from EVERLAST-A, including efficacy at Week 52 for all patients, in December 2026. The Company also continues to advance the EVERLAST-B Phase 2b trial of ORKA-001, with data expected during the fourth quarter of 2026.