Biogen Achieves Breakthrough Therapy Designation for Felzartamab, Shares Rise

Shares in Biogen experienced a slight increase following the announcement that its investigational antibody, felzartamab, has been granted breakthrough therapy designation by US regulators for the treatment of late antibody-mediated rejection in kidney transplant patients.

In a statement, the Massachusetts-based company noted that this designation from the US Food and Drug Administration is reserved for drug candidates addressing serious or life-threatening conditions.

Biogen highlighted that these candidates have shown preliminary evidence of offering significant improvements over existing therapies. Travis Murdoch, Head of Biogen’s Human Immunology unit, emphasized, “Antibody-mediated rejection (AMR) is a major reason why kidney transplants fail, and patients suffering from AMR have a tremendous unmet medical need. We are committed to addressing this significant challenge, and the breakthrough therapy designation will facilitate efficient collaboration with the FDA to expedite the development of felzartamab for AMR.”

AMR occurs when the immune system produces antibodies that harm transplanted organs.

The company announced plans to initiate late-stage trials for felzartamab targeting AMR and two other types of kidney diseases in 2025. The treatment is still under investigation, has not been approved by any regulatory authority, and its safety and effectiveness have yet to be established.

This news comes after Biogen’s agreement in May to acquire HI-Bio for up to $1.8 billion, part of a strategy to enhance its portfolio of rare disease treatments. The deal includes an initial payment of $1.15 billion, with an additional potential $650 million tied to specific development milestones for felzartamab.

HI-Bio’s felzartamab has previously undergone mid-stage trials for primary membranous nephropathy and AMR. The San Francisco-based company is also exploring its use in patients with IgA nephropathy, another form of chronic kidney disease.