Oruka Reports Positive Interim Phase 1 Data for ORKA-002, Advances ORKA-001

Today, Oruka Therapeutics, Inc. reported positive interim findings from a phase 1 clinical trial of ORKA-002 and provided updates on the ongoing clinical development of ORKA-001.¹ Both programs are aimed at improving disease control while reducing dosing frequency, a key unmet need in chronic dermatologic conditions.

ORKA-002: Phase 1 Trial Design and Interim Results

ORKA-002 is a monoclonal antibody targeting the interleukin-17 (IL-17) pathway, a well-established driver of inflammation in psoriasis and other immune-mediated skin diseases such as hidradenitis suppurativa (HS). The phase 1 study was a first-in-human, randomized, double-blind, placebo-controlled trial designed to assess safety, tolerability, and pharmacokinetics (PK) in healthy volunteers.²

The trial enrolled 24 healthy adult participants across 3 single-ascending subcutaneous dose cohorts: 160 mg, 320 mg, and 640 mg. According to interim data with a January 2026 cutoff, ORKA-002 demonstrated a prolonged pharmacokinetic profile. The reported half-life ranged from approximately 75 to 80 days, which is more than 3 times longer than that reported for bimekizumab, an approved IL-17 inhibitor, based on previously published data. Peak serum concentrations were reported to be comparable to bimekizumab at equivalent doses.

Pharmacokinetic modeling based on these results suggests that ORKA-002 may support infrequent maintenance dosing, potentially twice yearly for plaque psoriasis and quarterly for HS. From a pharmacodynamic (PD) perspective, ORKA-002 showed sustained inhibition of IL-17 signaling in an ex vivo IL-17 stimulation assay. This inhibition was observed across all dose levels and persisted through the last follow-up, which extended up to 24 weeks.

Safety findings from the interim analysis were consistent with expectations for the anti-IL-17 drug class. ORKA-002 was reportedly well tolerated at all dose levels, with no severe treatment-emergent adverse events (TEAEs), serious adverse events, or treatment discontinuations. The most commonly reported TEAEs, occurring in more than 2 participants, included contusion, headache, skin abrasion, and upper respiratory tract infection. The study remains blinded, and all enrolled participants continue to be followed.

Planned Phase 2 Development for ORKA-002

Building on the phase 1 findings, Oruka plans to initiate a phase 2 trial in moderate to severe plaque psoriasis, referred to as ORCA-SURGE, in the first half of 2026. This randomized, double-blind, placebo-controlled, dose-ranging study is expected to enroll approximately 160 patients. Participants will be randomized equally to receive ORKA-002 at doses of 40 mg, 160 mg, or 320 mg at weeks 0 and 4, or placebo.

The primary endpoint of ORCA-SURGE will be the proportion of patients achieving a Psoriasis Area and Severity Index (PASI) 100 response, indicating complete skin clearance, at week 16. The study also includes a maintenance phase designed to evaluate the feasibility of twice-yearly dosing. Data from this trial are anticipated in 2027. Additionally, Oruka expects to initiate a separate phase 2 trial of ORKA-002 in patients with HS in the second half of 2026.

ORKA-001: Ongoing EVERLAST Clinical Program

Oruka also provided updates on ORKA-001, another investigational biologic targeting psoriatic disease. The EVERLAST-B phase 2 trial began dosing patients in December 2025 and is currently enrolling. This study is evaluating 3 induction regimens of ORKA-001—37.5 mg at week 0, 300 mg at weeks 0 and 4, and 600 mg at weeks 0 and 4—compared with placebo. The primary endpoint is PASI 100 at week 16.

Patients who achieve PASI 100 at week 28 will be re-randomized to either once-yearly 600 mg dosing or placebo, while non-responders will receive 300 mg every 6 months. This design aims to further assess the potential for extended dosing intervals and sustained disease control. Data from EVERLAST-B are expected in 2027.

The earlier EVERLAST-A study remains ongoing, with the company planning to report week 16 PASI 100 data for all participants, along with longer-term response duration data extending to approximately 1 year for some patients, in the second half of 2026.

Conclusion

Overall, the interim phase 1 results for ORKA-002 suggest a favorable safety profile and a pharmacokinetic and pharmacodynamic profile that could support infrequent dosing schedules. Together with the ongoing development of ORKA-001, Oruka Therapeutics is advancing a clinical strategy focused on durable efficacy and reduced treatment burden in chronic inflammatory skin diseases. Further data from planned phase 2 trials will be needed to determine the clinical relevance of these early findings.

References

1. Oruka Therapeutics announces positive interim phase 1 data for ORKA-002 and initiation of EVERLAST-B trial of ORKA-001. News release. Oruka Therapeutics. Published January 12, 2026. Accessed January 12, 2026. https://ir.orukatx.com/news-releases/news-release-details/oruka-therapeutics-announces-positive-interim-phase-1-data-orka
2. Oruka Therapeutics announces first participants dosed in phase 1 trial of ORKA-002, its novel half-life extended anti-IL-17A/F antibody. News release. Oruka Therapeutics. Published May 20, 2025. Accessed January 12, 2026. https://orukatx.gcs-web.com/news-releases/news-release-details/oruka-therapeutics-announces-first-participants-dosed-phase-1-0