Hansa Biopharma finishes enrolment for European Phase 3 kidney transplant study

Hansa Biopharma AB, based in Lund, Sweden, has announced the completion of enrollment for its significant 20-HMedIdeS-19 Post Authorization Efficacy and Safety (PAES) study. This Phase 3 open-label study is being conducted in Europe to evaluate the one-year survival rate of both patients and grafts in highly sensitized individuals who have undergone HLA-incompatible kidney transplants. The transplants are performed following a desensitization treatment using imlifidase, a pioneering therapy developed by Hansa. Branded as IDEFIRIX®, imlifidase is an innovative, first-generation treatment that has earned conditional approval in Europe for desensitizing kidney transplant patients.

Imlifidase is also undergoing advanced trials for its potential in addressing autoimmune diseases characterized by immunoglobulin G (IgG) antibodies and as a preparatory treatment for gene therapy for patients with anti-AAV antibodies. Hansa Biopharma expects to have data from the PAES study available in the latter half of 2026. The company plans to submit this data to the European Medicines Agency (EMA) to seek full authorization for IDEFIRIX®.

The PAES study was mandated following the conditional approval of IDEFIRIX® by the European Commission in 2020. Søren Tulstrup, President and CEO of Hansa Biopharma, emphasized that the PAES study is crucial in Hansa’s efforts to ensure access to IDEFIRIX for highly sensitized kidney transplant patients. He noted that finding compatible organs for these patients is challenging due to their immunological profiles, which significantly prolongs their wait times for transplants. Hansa believes the study will further validate the efficacy and safety of IDEFIRIX, supporting their application for full authorization in the EU.

This controlled, open-label study focuses on the one-year survival of kidney transplants without graft failure in highly sensitized patients who have a positive crossmatch with a deceased donor. These patients received desensitization treatment with imlifidase before undergoing HLA-incompatible transplantation. The study involves 50 highly sensitized adult kidney transplant recipients. Additionally, a reference group of 64 patients who did not require desensitization was included to account for variations in post-transplant management across different centers. The trial, conducted at 22 sites throughout Europe, also comprises a non-comparative registry of historical data.

Thomas Lorant, a transplant surgeon at Uppsala University and the trial's coordinating investigator, highlighted the transformative impact of imlifidase on transplantation care for highly sensitized patients. By creating an IgG-free window, imlifidase inactivates donor-specific antibodies, making HLA-incompatible kidney transplantation a viable option for these patients. Lorant expressed confidence in imlifidase's role in enabling treatment for those with the greatest need for kidney transplants.

Highly sensitized patients possess pre-existing antibodies, known as donor-specific antibodies (DSAs), which react against human leukocyte antigens (HLAs) and can lead to tissue damage and transplant rejection. The presence of DSAs makes it difficult for these patients to find compatible donor organs, often resulting in extended wait times for transplants, which correlates with increased mortality risks. In both the U.S. and Europe, highly sensitized patients represent about 10-15% of individuals on kidney transplant waiting lists.

Imlifidase is an enzyme derived from Streptococcus pyogenes that cleaves IgG antibodies, inhibiting the IgG-mediated immune response. It has a rapid onset, effective within hours of administration, and is used in Europe under the brand name IDEFIRIX for desensitizing highly sensitized kidney transplant patients with a positive crossmatch against deceased donors. This treatment is reserved for patients unlikely to receive a transplant through existing kidney allocation systems, including those that prioritize highly sensitized patients.

Hansa Biopharma is a commercial-stage biopharmaceutical company dedicated to developing treatments for rare immunological conditions, utilizing its proprietary IgG-cleaving enzyme technology platform. The company's portfolio includes imlifidase and HNSA-5487, a second-generation IgG-cleaving molecule. With its headquarters in Lund and operations in Europe and the U.S., Hansa Biopharma is a publicly traded entity on Nasdaq Stockholm under the ticker HNSA.