Hansa Biopharma (Nasdaq Stockholm: HNSA) has reported that imlifidase (Idefirix) achieved 90% one-year graft failure-free survival in a post-authorization confirmatory study of highly sensitized patients undergoing Idefirix kidney transplant desensitization — data the Swedish company says support a planned submission to the European Medicines Agency for conversion to full marketing authorization.
The 20-HMedIdeS-19 Post Authorization Efficacy Study (PAES) is an open-label confirmatory study required by the EMA as a condition of imlifidase's 2020 conditional approval. It enrolled 51 highly sensitized adult patients across 22 transplant centers in 11 EU and UK countries, with the first patient entering in May 2022. The population comprised patients with pre-formed donor-specific antibodies and a positive crossmatch against a deceased donor — individuals who, without intervention, would typically remain on transplant waiting lists for extended or indefinite periods. Imlifidase works by rapidly cleaving all circulating IgG antibodies, including donor-specific IgG, converting a positive crossmatch to negative within hours and opening a window for transplantation.
The primary endpoint — one-year graft failure-free survival, defined as freedom from permanent return to dialysis, retransplantation, transplantectomy, or death — was met at 90%. Graft survival at one year was 92% and patient survival reached 98%. Mean estimated glomerular filtration rate at one year was 52.4 mL/min/1.73 m², indicating functional kidney activity in transplanted patients. Patient retention exceeded 94%, which the company described as reflecting well-conducted study execution. Idefirix was generally well tolerated, with a safety profile consistent with prior clinical trial experience; no new safety signals were reported. Hansa said the post-authorization obligation is now considered fulfilled and plans to submit an application for EMA full marketing authorization conversion by Q4 2026.