Affibody, Acelyrin and Inmagene Biopharmaceuticals have announced that a 16-week, global, Phase 2 clinical trial of izokibep in 135 patients with psoriatic arthritis (PsA) met its primary endpoint of ACR50.

Izokibep also achieved secondary endpoints, including PASI response, enthesitis LEEDs improvement, and quality of life improvement on a clinically validated PsA-specific quality of life instrument, the Psoriatic Impact of Disease (PsAID) questionnaire, state the companies.

“Psoriatic arthritis is a painful and debilitating inflammatory disease of the peripheral joints, skin, and nails, and it also can affect the spine. We are pleased this Phase 2 trial highlights the potential of izokibep to offer clinically differentiated efficacy in this area of continued unmet need,” says Nikolai Brun, CMO of Affibody. “Importantly, an opportunity remains to continue to explore higher exposures to optimize response and still deliver izokibep as single SC injections.”

Affibody holds commercialization rights in the Nordic countries

The randomized double-blind, placebo-controlled, Phase 2 clinical trial evaluated the safety and efficacy of izokibep dosed 80 mg every two weeks (Q2W) or 40 mg Q2W, versus placebo Q2W, in adult patients with active PsA. The primary endpoint of ACR50 and secondary endpoint of PASI responses were met and were at the top of the range of responses, compared to what has been reported for other medicines approved or in development for PsA. The proportion of patients with resolution of enthesitis appears to be differentiating. A clinically meaningful improvement in disease-specific quality of life was achieved with the patient-reported outcome measure, PsAID. No new safety issues were identified.

Acelyrin holds worldwide rights to izokibep except development and commercialization rights by Inmagene in selected Asian countries, including China, Hong Kong, South Korea, and Taiwan, and excluding Japan. Affibody holds commercialization rights in the Nordic countries.

“These study results are important in demonstrating the opportunity to create best-in-class compounds based on the Affibody technology,” says David Bejker, CEO of Affibody.

Photo of David Bejker, CEO, Affibody