GSK to Acquire RAPT Therapeutics for $2.2 Billion

GSK (LSE/NYSE: GSK) has announced a definitive agreement to acquire RAPT Therapeutics (NASDAQ: RAPT) for $58.00 per share in cash, valuing the company at an estimated aggregate equity value of $2.2 billion.

This acquisition brings ozureprubart, a potentially best-in-class anti-IgE antibody in development for prophylactic protection against food allergens, into GSK's Respiratory, Immunology & Inflammation pipeline. The net upfront investment for GSK is estimated at $1.9 billion, net of cash acquired.

The deal centers on ozureprubart, a long-acting anti-IgE monoclonal antibody currently in phase IIb clinical development. This drug offers the potential for less frequent dosing (every 12 weeks) compared to existing anti-IgE treatments, which typically require injections every 2 to 4 weeks. Such a reduction in dosing frequency could significantly improve patient compliance and outcomes, addressing a critical unmet need in food allergy management.

Food allergies are on the rise, affecting over 17 million people in the US alone and resulting in over 3 million hospital and emergency care visits annually. Current anti-IgE treatments, while effective, present a significant burden for patients, particularly children. Ozureprubart aims to alleviate this burden and provide a new option for approximately 25% of patients currently ineligible for existing therapies.

Data from the phase IIb trial (prestIgE) assessing ozureprubart as monotherapy is expected in 2027, with phase III trials planned for both adult and pediatric populations. The acquisition aligns with GSK's strategy to acquire assets targeting validated pathways with clear unmet medical needs.

Tony Wood, Chief Scientific Officer, GSK, stated, “The addition of ozureprubart brings another promising new, potential best-in-class treatment to GSK's pipeline…Ozureprubart offers the opportunity to bring sustained protection to patients with dosing every 12 weeks, and is consistent with our approach to acquire assets that address validated targets and where there is clear unmet medical need.”

Brian Wong, President & Chief Executive Officer, RAPT Therapeutics, said, “We are excited to enter into this agreement with GSK, which offers an attractive path forward for our programs, particularly the opportunity we envision for ozureprubart in food allergy. This transaction has the potential to provide access to the global development and commercialisation capabilities, resources and infrastructure that GSK has to offer and ultimately bring added value to our pipeline, patients and stockholders.”

The transaction grants GSK global rights to the ozureprubart program, excluding mainland China, Macau, Taiwan, and Hong Kong.

GSK will also be responsible for success-based milestone and royalty payments owed to RAPT's partner, Shanghai Jeyou Pharmaceutical Co., Ltd.

The acquisition is expected to close in the first quarter of 2026, pending customary closing conditions, including the tender of a majority of RAPT's outstanding shares and regulatory approvals.