FDA Gives Thumbs-up for Phase 2 Trial of Izokibep in AS Patients

The U.S. Food and Drug Administration (FDA) has cleared the start of a Phase 2 trial of izokibep in people with ankylosing spondylitis (AS), according to the therapy’s developers Affibody AB and Inmagene Biopharmaceuticals.

“Obtaining FDA IND [investigational new drug] clearance is an important milestone for the izokibep program,” Jean-Louis Saillot, MD, Inmagene‘s chief development officer, said in a press release.

“Working closely with our partner Affibody, the Inmagene team is excited to develop a potentially best-in-class treatment to improve the condition and life quality for AS patients,” he added.

The planned Phase 2 study will evaluate the safety, efficacy, and tolerability of three dosing regimens of izokibep in about 300 patients with active AS over the course of one year. Treatment will be compared with a placebo.

Also called IMG-020 andABY-035, izokibep is an engineered protein. According to Inmagene, it binds to interleukin-17A (IL-17A) with about 1,000 times the strength than a typical IL-17 antibody.

IL-17A is a pro-inflammatory protein associated with AS and several other inflammatory conditions. Although carrying a risk of candida (fungal) infection, IL-17 inhibitors show potential in treating AS.  Izokibep has not demonstrated significantly more infections than a placebo, Inmagene reports.

Izokibep is designed to have a long half-life — the length of time it takes for the medication to lose half its starting concentration in the body — and high potency in a small molecule format. It was created by combining Affibody’s protein therapeutics platform and Albumod technology, and is intended to be administered at home as a subcutaneous, or under-the-skin, injection.

“We believe that izokibep is well positioned to improve the life of patients with AS with its high potency and strong safety profile,” said Fredrik Frejd, PhD, chief science officer of Affibody. “In addition, the IL-17 biology offers ample scope for further development and commercialization. We look forward to exploring the drug’s use to address multiple indications.”

The therapy candidate is also being investigated as a treatment for psoriatic arthritis in a separate Phase 2 study (NCT04713072). Enrollment is ongoing at a site in Germany; more information here.

The co-developers plan to file more IND applications this year requesting to begin clinical testing of izokibep in other autoimmune diseases.