Biogen to Acquire HI-Bio in Deal Worth Potentially Up to $1.8 Billion

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With the acquisition, Biogen gains felzartamab, HI-Bio's lead investigational mAb candidate being developed for the treatment of a range of immune-mediated diseases.

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On May 22, 2024, Biogen announced that it is acquiring Human Immunology Biosciences (HI-Bio), a privately-held US-based clinical-stage biotechnology company specializing in targeted therapies for severe immune-mediated diseases (IMDs). The transaction is worth potentially up to $1.8 billion, which includes a $1.15 billion upfront payment and up to $650 million in potential milestone payments. The deal is expected to close in the third quarter of 2024, subject to necessary regulatory approvals and customary closing conditions.

With the acquisition, Biogen gains felzartamab, HI-Bio’s lead asset. Felzartamab is a fully human anti-CD38 monoclonal antibody (mAb) that has been shown to selectively deplete CD38+ cells in clinical studies. This selective depletion includes plasma cells and natural killer (NK) cells. This action may allow for additional applications that improve clinical outcomes in a broad range of immune-mediated diseases, Biogen stated in a company press release.

“We believe this late-stage asset, which has demonstrated impact on key biomarkers and clinical endpoints in three renal diseases with serious unmet needs, is a strategic addition to the Biogen portfolio as we continue to augment our pipeline and build on our expertise in immunology,” said Priya Singhal, MD, head of Development at Biogen, in the press release. “We look forward to welcoming HI-Bio employees into Biogen and, together, working to advance potential therapies for patients with rare immune diseases with high unmet need.”

FDA has granted felzartamab breakthrough therapy designation and orphan drug designation for development in treating primary membranous nephropathy (PMN). The mAb has also received orphan drug designation for treating antibody-mediated rejection (AMR) in kidney transplant recipients. Felzartamab has completed Phase II studies in PMN and AMR and remains in ongoing Phase II studies in immunoglobulin A nephropathy (IgAN). HI-Bio plans to advance the mAb to Phase III studies in each indication; the company is presenting two abstracts at the European Renal Association Congress in Stockholm, which is occurring May 23–26, 2024. HI-Bio’s presentation includes complete Phase II data from the AMR study in kidney transplant patients and interim data from the Phase II IgAN study, according to the press release. Studies have also generated clinical data for felzartamab in the AMR, PMN, and IgAN indications.


“With its deep development and commercialization capabilities, Biogen is in a position to accelerate the development of new medicines, including felzartamab, for patients with severe immune-mediated diseases,” said Travis Murdoch, MD, chief executive officer of HI-Bio, in the release. “We are excited to combine the HI-Bio team’s expertise with Biogen’s global footprint.”

In addition to the felzartamab lead program, HI-Bio’s pipeline consists of izastobart/HIB210, an anti-C5aR1 antibody currently in a Phase I trial. This candidate has the potential for continued development in a range of complement-mediated diseases. HI-Bio also has discovery-stage mast cell programs with potential application in a range of immune-mediated diseases.

The treatment of IMDs has largely benefitted from the evolution of targeted biologic therapies. Targeted biologics have demonstrated efficacy, speed of onset, and tolerability. What’s more, research efforts have shown that clinically unrelated immune-mediated inflammatory conditions can share similar immune dysregulation. This discovery has since led to a shift in way IMDs and other inflammatory disorders are managed (1).


1. Kuek, A.; Hazleman, B. L.; Ostör A. J. Immune-Mediated Inflammatory Diseases (IMIDs) and Biologic Therapy: A Medical Revolution. Postgrad Med J. 2007, 83 (978), 251–260. DOI: 10.1136/pgmj.2006.052688

Source: Biogen