Hansa Biopharma’s Idefrix (imlifidase) has seen a 90% one-year survival from graft versus host disease (GvHD) in patients following a kidney transplant, supporting full approval.
The open-label, European 20-HMedIdeS-19 post-authorisation efficacy study (PAES) (NCT05369975) investigated one-year graft failure-free survival and patient survival in highly sensitised patients who have undergone human leukocyte antigen (HLA)-incompatible kidney transplantation following desensitisation treatment with Idefirix.
A total of 51 patients were enrolled and treated with Idefirix from 22 transplant centres across 11 countries in the European Union (EU) and the UK.
The primary endpoint was met, with 90% of patients achieving one-year graft failure-free survival.
The secondary endpoint of renal function one year after transplantation, assessed by estimated glomerular filtration rate (eGFR), was met, with a rate of 52.4mL/min/1.73m², graft survival of 92%, and patient survival of 98%.
Idefirix was generally well tolerated, with a safety profile consistent with previous clinical trial experience, and retention was above 94%.
Hansa Biopharma CEO Renée Aguiar-Lucander said: "These positive results represent a significant milestone for Idefirix and for Hansa. The one-year graft failure-free survival observed in this highly sensitised patient population confirms the clinical benefit of Idefirix and demonstrates expected efficacy outcomes supported by a safety profile consistent with prior clinical experience."
Imlifidase is conditionally approved in the EU under the brand name Idefirix, subject to the successful completion of the PAES. Following completion of the study, Hansa plans to engage with the European Medicines Agency (EMA) for full approval of the drug by the end of this year.
While Hansa said it will submit the application, the rights for the drug in the EU and other regions are set to change hands. This month, SERB Pharmaceuticals signed an agreement to acquire exclusive development and commercialisation rights to Idefirix from Hansa Biopharma for a total of €115m ($133.6m). The deal covers the EU, Iceland, Liechtenstein, Norway, Switzerland, the UK, and the Middle East and North Africa (MENA) region.
Idefirix has not been approved for use in the US; however, Hansa submitted a biologics licence application (BLA) to the US Food and Drug Administration (FDA) in February 2026. The Prescription Drug User Fee Act (PDUFA) target action date is set for 19 December 2026.
In addition to its success as a transplant medication, Idefrix has also shown promise as a pre-treatment in gene therapy settings. The drug has been investigated in collaboration with Sarepta Biosciences and Roche’s Elevidys (delandistrogene moxeparvovec). In a Phase I study, it was administered before gene therapy dosing and was shown to reduce patients' immunoglobulin G (IgG) antibodies, thereby enabling eligibility for treatment.
