Oruka's Psoriasis Drug Shows Promise for Once-a-Year Treatment

Oruka's Psoriasis Drug Shows Promise for Once-a-Year Treatment

MENLO PARK, CA – April 27, 2026 – Oruka Therapeutics, a clinical-stage biotechnology company, has announced highly encouraging results from a mid-stage trial of its investigational psoriasis treatment, ORKA-001. The data, from the Phase 2a EVERLAST-A study, showed that the drug led to complete skin clearance in a significant majority of patients with moderate-to-severe plaque psoriasis, fueling hopes for a potential once-yearly treatment option.

In the study, an impressive 63.5% of patients receiving ORKA-001 achieved a Psoriasis Area and Severity Index (PASI) 100 score, which signifies a complete or near-complete clearance of skin plaques, after just 16 weeks. This level of efficacy, combined with a favorable safety profile, positions the drug as a potentially transformative therapy in a competitive market.

“These data reached the top end of what we could have expected from ORKA-001 across efficacy, tolerability, and potential for long-lasting response,” said Dr. Joana Goncalves, Chief Medical Officer of Oruka. “We’re thrilled with the profile that is emerging for this program and are excited to see how the data mature with longer-term follow-up.”

A New Benchmark in Efficacy?

The EVERLAST-A trial was a randomized, double-blind, placebo-controlled study involving 84 patients across the United States and Canada. Participants received either 600 mg of ORKA-001 or a placebo at the start of the trial and again at week four. The results at the 16-week mark were striking. Beyond the 63.5% who achieved PASI 100, 83% of patients on ORKA-001 reached PASI 90, a measure indicating at least a 90% improvement in their skin condition. In contrast, only one patient in the placebo group achieved these endpoints.

These efficacy numbers are noteworthy when compared to existing treatments. The current market for psoriasis biologics is dominated by drugs targeting inflammatory pathways, including the IL-23/IL-17 axis. Leading IL-23 inhibitors like Skyrizi (risankizumab) and Tremfya (guselkumab) have demonstrated PASI 90 rates in the range of 70-75% and PASI 100 rates around 40-50% in their pivotal 16-week studies. While cross-trial comparisons have limitations, ORKA-001's initial data appears to set a new high-water mark for the IL-23p19 class and is competitive with the best-in-class therapies across all mechanisms.

“If this type of efficacy and safety profile could be available with dosing once to twice per year, it would represent a major step forward for the field,” commented Dr. Bruce Strober, a Clinical Professor of Dermatology at Yale University School of Medicine and the lead investigator for the trial. “I could envision this being the preferred product for any patient with moderate-to-severe psoriasis.”

The Promise of Less Frequent Dosing

Perhaps the most significant differentiator for ORKA-001 is its potential for a once-yearly dosing schedule. For patients with chronic conditions like psoriasis, reducing the frequency of injections can dramatically improve quality of life and treatment adherence. Most current biologics require injections every four, eight, or twelve weeks. Oruka’s drug is an engineered antibody with an extended half-life, designed to remain active in the body for a much longer period.

Supporting this potential, the company released updated pharmacokinetic (PK) and pharmacodynamic (PD) data from its Phase 1 study. The results showed that after a single 600 mg dose, the concentration of ORKA-001 in the body remained at a therapeutically effective level for an entire year. This sustained exposure was correlated with a durable suppression of the IL-23 pathway, the biological target of the drug. The company also reported no concerning safety signals, with the most common side effect being mild upper respiratory tract infections, occurring at a rate similar to placebo.

A Competitive Landscape and the Road Ahead

The market for psoriasis treatments is a multi-billion dollar industry, and a new entrant with a best-in-class profile could capture significant share. Oruka Therapeutics, a company focused on developing novel biologics for chronic skin diseases, appears poised to challenge established players if further trials confirm these early findings.

Investors and clinicians will be eagerly awaiting the next data readouts. Oruka has announced plans to share longer-term data from the EVERLAST-A trial, including 28-week efficacy data for all patients and 52-week data for a subset of the cohort, in the second half of 2026. These results will be critical in confirming the durability of the response and the viability of an annual dosing regimen. Following this, the company will proceed with its Phase 2b EVERLAST-B trial, with results anticipated in 2027, which will further define the optimal dose and set the stage for pivotal Phase 3 studies required for regulatory approval.