Oruka Therapeutics Shares Climb 11% as Psoriasis Drug Fully Clears Skin in 61% of Patients in Mid-Stage Trial

Shares of Oruka Therapeutics Inc. rose more than 11% on Monday. The biotechnology company reported that its experimental psoriasis drug completely cleared patients' skin in a majority of cases at its highest dose in a mid-stage trial, results the study's lead investigator said could make it the most effective treatment of its kind.

Oruka shares gained $9.21, or 11.49%, to $89.36 in morning trading on the Nasdaq. The company's market value rose to about $5.9 billion.

The stock is up about 189% over the past 52 weeks, making Oruka one of the best-performing biotech stocks of the year.

Trial results

Oruka reported 16-week results from EVERLAST-B, a Phase 2b study of ORKA-001 in adults with moderate-to-severe plaque psoriasis. The randomized, double-blind, placebo-controlled trial enrolled 187 patients at 36 sites in the United States, Canada and Europe.

ORKA-001 is an antibody that blocks interleukin-23, an immune protein that drives psoriasis. Patients received one of three dosing regimens or a placebo.

The trial's main goal was PASI 100, a measure of complete skin clearance. At week 16:

600 mg (two doses, at weeks 0 and 4): 61% achieved complete clearance, and 86% achieved PASI 90, or at least 90% improvement. 300 mg (two doses): 44% achieved complete clearance, and 85% reached PASI 90. 37.5 mg (single dose): 43% achieved complete clearance, and 70% reached PASI 90. Placebo: No patients achieved either measure.

The result for the highest dose was highly statistically significant compared with placebo, and responses rose with dose.

"These results suggest ORKA-001 is likely to be the most effective IL-23-targeting biologic to date," said Dr. Joel Gelfand of the University of Pennsylvania, the lead investigator for the trial.

Safety profile

Through 16 weeks, 49% of patients on ORKA-001 reported at least one side effect, compared with 43% of patients on placebo. In the 600 mg group, 39% reported a side effect, and none were serious or severe.

The most common side effects were upper respiratory infections and headache. The company said there were no injection-site reactions and no dose-related trend in side effects. Serious adverse events occurred in 2% of patients on ORKA-001, and none were considered related to treatment.

Once-a-year goal

Oruka is betting on dosing as much as on effectiveness. The company is aiming for a treatment that keeps psoriasis clear with injections given only once or twice a year. Most existing biologics require injections every few weeks or months.

In the next phase of EVERLAST-B, patients whose skin cleared completely will be randomly assigned at week 28 to receive either 600 mg once a year or placebo. Patients who didn't fully clear will receive 300 mg every six months. The study will run through week 100.

The company plans to discuss Phase 3 development with regulators. Pending those talks, it expects to begin Phase 3 trials of the 600 mg regimen in the first half of 2027. Oruka expects 52-week results from a separate study, EVERLAST-A, in December, and 52-week EVERLAST-B data in the second half of 2027.

Competitive market

Psoriasis is a large, competitive market. It is dominated by injected biologics, including the IL-23 blockers Skyrizi from AbbVie and Tremfya from Johnson & Johnson. Several companies are also developing oral treatments.

Analysts say a drug that delivers higher clearance rates with far less frequent dosing could win market share if long-term results hold up. Monday's results cover only 16 weeks, and the company's once-yearly dosing approach has not yet been tested in the maintenance phase.

Oruka, based in Menlo Park, California, hosted a conference call Monday morning to discuss the data.

The broader biotech sector was active Monday, with several companies reporting data around major medical meetings. Markets overall were mixed ahead of the Fed's interest rate decision on Wednesday.

_This article is for information only and does not constitute financial advice._