GSK PLC (LSE:GSK, NYSE:GSK) has struck a $2.2 billion deal to buy US biotech firm RAPT Therapeutics, adding a potential new treatment for food allergies to its pipeline.
The acquisition gives GSK rights to ozureprubart, a long-acting antibody drug currently in mid-stage trials. It is designed to block IgE, a key part of the immune system that triggers most serious food allergy reactions.
Existing anti-IgE therapies require injections every two to four weeks. Ozureprubart is aiming for longer-lasting protection with just one dose every 12 weeks, which could make treatment far more manageable, especially for children, who account for the majority of severe cases.
The deal is part of GSK’s push into immune-related conditions and adds to its respiratory and inflammation portfolio. RAPT, based in California, specialises in inflammatory and immunologic diseases.
Under the terms of the deal, GSK will pay $58 per share in cash, valuing RAPT at $2.2 billion.
Adjusting for cash on RAPT’s books, the net upfront cost is expected to be $1.9 billion. The transaction is expected to be completed in the first quarter of 2026.
GSK's global rights to ozureprubart will exclude China, Hong Kong, Macau and Taiwan.
The FTSE 100 group has also agreed a reshuffle of ownership in specialist HIV company ViiV Healthcare, as Pfizer Inc (NYSE:PFE) exits and Japan’s Shionogi increases its stake to 21.7%.
GSK will receive a $250 million special dividend, as it retains a 78.3% stake in the company behind treatments like dolutegravir and cabotegravir.
The deal values Shionogi’s investment at $2.125 billion, with Pfizer receiving $1.875 billion and GSK a $250 million special dividend.