Hansa Biopharma’s Biologics License Application (BLA) for imlifidase has been accepted by the US Food and Drug Administration (FDA), marking a key milestone in the enzyme’s path toward enabling HLA-incompatible kidney transplantation.

FDA completed its initial filing review on day 60 to confirm the submission is substantially complete and ready for full evaluation.

Renée Aguiar-Lucander, CEO of Hansa Biopharma, said: “We now look forward to receiving the 74-Day Letter which will provide details regarding review plan, timelines and other pertinent information and start working with the FDA as they go through their review over the coming months.”

Imlifidase is a unique IgG-cleaving enzyme that rapidly inactivates over 95% of donor-specific antibodies within 2–6 hours of administration. This action provides a crucial window to allow kidney transplants for patients who would otherwise be incompatible with available donors.

The BLA submission is supported by results from the pivotal Phase 3 ConfIdeS trial in the US, which compared 12-month kidney function in highly sensitized adult patients (cPRA ≥99.9%) receiving imlifidase to a control arm.

The trial met its primary endpoint, showing significantly improved kidney function in the imlifidase group at 12 months as measured by mean estimated glomerular filtration rate (eGFR) (p < 0.0001). A key secondary endpoint—dialysis independence at 12 months—also favored imlifidase (p = 0.0007). The enzyme was generally well tolerated, consistent with prior clinical trial experience.

ConfIdeS is a pivotal, open-label Phase 3 trial that included 64 patients across 25 US sites. It is part of a five-year programme including long-term follow-up agreed with the FDA under the accelerated approval pathway.