By Fineline Cube GlaxoSmithKline plc (GSK, NYSE: GSK) announced a definitive agreement to acquire RAPT Therapeutics (NASDAQ: RAPT) for USD 58.00 per share, representing an aggregate equity value of $2.2 billion and a net upfront investment of $1.9 billion. The acquisition grants GSK global rights to ozureprubart (excluding Greater China), a long‑acting anti‑IgE monoclonal antibody in Phase 2b development for prophylactic protection against food allergens.
Transaction Overview
| Item | Detail |
|---|---|
| Acquirer | GlaxoSmithKline plc (NYSE: GSK) |
| Target | RAPT Therapeutics (NASDAQ: RAPT) |
| Purchase Price | USD 58.00 per share |
| Equity Value | USD 2.2 billion |
| Net Investment | USD 1.9 billion (net of cash acquired) |
| Expected Close | Q1 2026 |
| Key Asset | Ozureprubart (long‑acting anti‑IgE mAb) |
| Rights Acquired | Global rights excluding Greater China (owned by Jemincare) |
| Development Stage | Phase 2b (prestIgE trial) |
| Indication | Prophylactic protection against food allergens |
| Phase 2b Data | Expected 2027 |
Drug Profile & Mechanism
- Mechanism: Anti‑immunoglobulin E (IgE) monoclonal antibody that neutralizes IgE, preventing allergic cascade triggered by food allergens
- Long‑Acting: Designed for extended duration vs. short‑acting anti‑IgE therapies (e.g., omalizumab)
- Clinical Development:
- Phase 2b (prestIgE) – Monotherapy for at‑risk adult and pediatric populations
- Phase 3 planned – to expand across food allergy indications (peanut, milk, egg)
- Differentiation: Potential first‑in‑class long‑acting prophylactic for food allergies vs. oral immunotherapy (Aimmune, DBV)
Market Opportunity & Competitive Landscape
| Parameter | Food Allergy Market | Anti‑IgE Market |
|---|---|---|
| Food Allergy Prevalence (US) | 8% children, 11% adults | – |
| Severe/Requiring Prophylaxis | 1.6 million (US) | – |
| Current Standard | Epinephrine (reactive), oral immunotherapy (partial efficacy) | |
| Omalizumab Sales (2025) | – | $3.8 billion (Xolair) |
| Prophylactic Anti‑IgE Market (2030E) | $4.5 billion | – |
| **Ozureprubart Peak Share | 12% | – |
| Peak Revenue (2032E) | $540 million | – |
Key Competitors:
- Omalizumab (Roche/Novartis) – Short‑acting anti‑IgE, approved for asthma/food allergy off‑label
- Ligelizumab (Novartis) – Next‑gen anti‑IgE, Phase III for food allergy
- Oral Immunotherapy: Palforzia (Aimmune/Nestlé) – Peanut OIT, limited efficacy and safety concerns
- Ozureprubart – Long‑acting prophylactic with potential for monthly‑quarterly dosing, avoiding daily OIT burden
Strategic Positioning
- For GSK:
- Complements allergy franchise (Nucala, Xolair) with first‑in‑class food allergy prophylactic
- Leverages GSK’s commercial footprint in allergy/immunology (12,000 US prescribers)
- Platform potential: Anti‑IgE technology applicable to asthma, chronic urticaria, and other allergic diseases
- Manufacturing: RAPT’s Hayward, CA facility will be integrated into GSK’s biologics network; scale‑up for Phase 3 planned 2027
- Regulatory Path: BTD expected after Phase 2b data; PDUFA target 2029
Forward‑Looking Statements
This brief contains forward‑looking statements regarding transaction completion, clinical development timelines, and commercial forecasts for ozureprubart. Actual results may differ due to clinical trial outcomes, competitive responses, and regulatory approval processes.-Fineline Info & Tech