LUND, Sweden, May 27, 2026
Hansa Biopharma AB has announced positive topline results from its European Post Authorization Efficacy Study (PAES) evaluating Idefirix® (imlifidase) in highly sensitized kidney transplant patients. The open-label confirmatory study demonstrated that 90% of patients achieved one-year graft failure-free survival, reinforcing the clinical value of Idefirix as a desensitization therapy for patients who previously faced limited or no access to compatible kidney transplants. The results also support Hansa Biopharma’s plans to submit an application to the European Medicines Agency (EMA) for conversion of Idefirix from conditional approval to full marketing authorization by the end of 2026.
The PAES study evaluated highly sensitized adult kidney transplant patients who underwent HLA-incompatible transplantation following pre-treatment with Idefirix. The therapy is specifically designed to rapidly eliminate donor-specific IgG antibodies that can otherwise trigger organ rejection and prevent successful transplantation. According to Hansa Biopharma, the study met its primary endpoint while also demonstrating a safety profile consistent with previous clinical trial experience. Researchers believe the findings further validate Idefirix as a transformative treatment option for patients with severe immunological barriers to transplantation.
Idefirix Demonstrates Strong Kidney Transplant Outcomes
The European PAES study enrolled 51 highly sensitized kidney transplant patients across 22 transplant centers in 11 countries throughout Europe and the United Kingdom. The first patient entered the study in May 2022, and investigators evaluated one-year graft failure-free survival and patient survival following desensitization treatment with Idefirix prior to kidney transplantation.
According to the study results, one-year graft survival reached 92%, while patient survival reached 98%. Researchers additionally reported a mean estimated glomerular filtration rate (eGFR) of 52.4 mL/min/1.73 m² one year after transplantation, indicating strong renal function among treated patients. The study also reported patient retention rates exceeding 94%, supporting the robustness of the clinical data and long-term follow-up outcomes.
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Renée Aguiar-Lucander, Chief Executive Officer of Hansa Biopharma, described the findings as a major milestone for both the company and the transplant community. She stated that the positive results confirm the clinical benefit of Idefirix and demonstrate expected efficacy outcomes supported by a favorable and predictable safety profile. The company now intends to move forward with its submission for full EMA marketing authorization later this year.
Highly Sensitized Patients Face Major Transplant Challenges
Highly sensitized kidney transplant patients possess pre-formed donor-specific antibodies against human leukocyte antigens (HLAs), significantly increasing the risk of transplant rejection and making compatible donor matching extremely difficult. These patients frequently spend extended periods on transplant waiting lists and often face elevated mortality risk while awaiting suitable organs.
Idefirix is a first-in-class IgG-cleaving enzyme therapy originating from Streptococcus pyogenes that rapidly removes IgG antibodies within hours after administration. By temporarily eliminating donor-specific antibodies prior to transplantation, the therapy enables transplantation in patients who would otherwise remain ineligible due to positive crossmatch results.
Tomas Lorant, Associate Professor and transplant surgeon at Akademiska Hospital and Uppsala University, stated that imlifidase is already transforming transplantation care across Europe by enabling access to kidney transplantation for patients with some of the highest unmet medical needs in transplant medicine. Investigators believe the latest PAES findings further strengthen confidence in the therapy’s ability to expand transplant access for difficult-to-treat patient populations.
Regulatory Momentum Expands for Idefirix
Idefirix currently holds conditional marketing approval in the European Union, United Kingdom, Norway, Iceland, Liechtenstein, Australia, Israel, and Switzerland. The therapy previously received support through the EMA’s PRIority Medicines (PRIME) program, which is reserved for medicines with the potential to provide major therapeutic advantages for patients lacking effective treatment options.
In addition to European regulatory progress, Hansa Biopharma confirmed that the U.S. Food and Drug Administration (FDA) accepted the company’s Biologics License Application (BLA) for imlifidase earlier this year and assigned a PDUFA action date of December 19, 2026. The latest European study findings are expected to further strengthen the global regulatory profile of the therapy as Hansa expands commercialization efforts in transplantation and immunology.
Industry analysts believe therapies capable of enabling transplantation in highly sensitized patients may play an increasingly important role in addressing growing global demand for kidney transplantation while improving survival outcomes and reducing long-term dependence on dialysis treatment.
Source: Hansa Biopharma press release
