Affibody Medical Investor Relations

Positive Long-term Results with Izokibep in Psoriatic Arthritis


April 11, 2023

• Affibody’s partner ACELYRIN, INC today announced 46 weeks Phase 2 data where izokibep demonstrated high levels of response across psoriatic arthritis disease manifestations.
• Long-term data build on statistically significant improvements demonstrated at 16 weeks across key measures of joint pain, psoriasis, and enthesitis resolution.
• With longer duration of therapy, izokibep remained generally well-tolerated and safety data at week 46 were consistent with that previously observed for izokibep in psoriatic arthritis.
Solna, Sweden, April 11, 2023. Affibody today shared long-term 46-week data from a global Phase 2 trial of izokibep in psoriatic arthritis (PsA) as announced by our partner ACELYRIN.
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 global study assessed various endpoints including the American College of Rheumatology (ACR) response, the Psoriasis Area and Severity Index (PASI) score and the Leeds Enthesitis Index (LEI). At Week 16, the placebo cohort transitioned to 80 mg izokibep Q2W. The trial treatment period continued for up to 46 weeks.
The 46-week data announced by our partner ACELYRIN today demonstrate continued and marked improvements in key areas of psoriatic arthritis including joint pain, skin psoriasis, and enthesitis,” said Nikolai Brun, CMO of Affibody

  Izokibep 80 mg Q2W,
as observed at 46 weeks
Izokibep 40 mg Q2W,
as observed at 46 weeks
Izokibep Pbo to 80 mg Q2W,
as observed at 46 weeks
ACR50 79% 50% 73%
ACR70 50% 33% 64%
PASI100 71% 50% 67%
Enthesitis Resolution 89% 83% 80%

Through week 46 of this Phase 2 trial, izokibep was generally well-tolerated – in line with previous trials of izokibep. The most common adverse event (AE) was injection site reactions. Injection site reactions were localized reactions, with the majority graded mild-to-moderate in severity, generally 25-30 mm in diameter, and typically presented within the first few injections, after which they declined in incidence. In the trial, one serious adverse event (vulvar cancer) which was determined to be potentially drug-related was observed.
The full 46-week data from this trial will be presented at a future scientific meeting. Izokibep is currently being evaluated in an ongoing Phase 2b/3 trial in PsA evaluating a range of doses, including higher doses than in the reported Phase 2 trial.
ACR50 response is defined as a 50% improvement in tender and swollen joints, along with improvement in three of these five parameters: (a) patient global assessment of disease activity; (b) physician global assessment of disease activity; (c) patient pain scale; (d) disability/functional questionnaire and (e) decreased concentration of C-reactive protein correlated to inflammation. ACR70 response is defined as a 70% improvement in features noted above for ACR50 response, and is considered by some clinicians to be an indicator of significant control of disease activity. PASI100 response is defined as 100% improvement in skin response, or complete resolution of psoriasis skin lesions. Enthesitis resolution is defined as no active entheseal sites on the Leeds Enthesitis Index (LEI).