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The Race to Protect 27 Million Americans from Accidental Food Allergen Exposure

The Race to Protect 27 Million Americans from Accidental Food Allergen Exposure

GSK's $2.2 Billion RAPT Acquisition Signals Big Pharma's Bet on IgE Blockade

Overview

For decades, the 27 million American adults and children with food allergies had one option: avoid the allergen and carry an EpiPen. That changed in February 2024 when the FDA approved Xolair as the first drug to reduce allergic reactions—including anaphylaxis—from accidental exposure to multiple foods. Now GSK has paid $2.2 billion for RAPT Therapeutics and its experimental antibody ozureprubart, betting it can build a better version with once-quarterly dosing instead of Xolair's every-two-to-four-week schedule.

The acquisition marks new CEO Luke Miels' first major move since taking the helm on January 1, 2026, and positions GSK to challenge Roche/Novartis's established Xolair franchise while racing against Novartis's oral BTK inhibitor remibrutinib. With GSK facing $230 billion in industry-wide patent losses by 2030—including its own $5.4 billion HIV blockbuster dolutegravir starting in 2028—the company is betting that the $3.5 billion food allergy market, projected to reach $9.2 billion by 2034, can help fill the gap.

Key Indicators

$2.2B
GSK acquisition price
65% premium over RAPT's closing price, with $1.9 billion net investment after cash adjustments
27M
Americans with food allergies
Nearly 11% of adults and 8% of children have at least one food allergy
12 weeks
Ozureprubart dosing interval
Potential best-in-class advantage vs. Xolair's 2-4 week dosing requirement
2027
Phase 2b data expected
prestIgE trial readout will determine ozureprubart's path forward

People Involved

Luke Miels
Luke Miels
CEO, GSK (Assumed role January 1, 2026)
Brian Wong, M.D., Ph.D.
Brian Wong, M.D., Ph.D.
President and CEO, RAPT Therapeutics (Leading company through acquisition)
Emma Walmsley
Emma Walmsley
Former CEO, GSK (Stepped down December 2025; notice period through September 2026)

Organizations Involved

GSK (GlaxoSmithKline)
GSK (GlaxoSmithKline)
Multinational pharmaceutical company
Status: Acquirer; expanding immunology portfolio ahead of patent cliffs

British pharmaceutical giant facing loss of U.S. patent protection on its $5.4 billion HIV drug dolutegravir beginning in 2028.

RA
RAPT Therapeutics, Inc.
Clinical-stage biopharmaceutical company
Status: Being acquired by GSK; deal expected to close Q1 2026

South San Francisco biotech that pivoted from oncology to immunology after FDA clinical hold on its cancer drug in 2024.

RO
Roche/Genentech
Multinational pharmaceutical company
Status: Incumbent; markets Xolair (with Novartis) for food allergy

Swiss pharma giant that co-promotes Xolair with Novartis—the first and currently only FDA-approved drug for food allergy prophylaxis.

NO
Novartis Pharmaceuticals
Multinational pharmaceutical company
Status: Competitor; developing oral BTK inhibitor for food allergy

Swiss pharma developing remibrutinib (Rhapsido), an oral BTK inhibitor being tested in peanut allergy that could offer pill-based alternative to injectables.

Timeline

  1. GSK announces $2.2B RAPT Therapeutics acquisition

    M&A

    GSK to pay $58 per share (~65% premium) for RAPT, gaining global rights to ozureprubart outside Greater China. Deal expected to close Q1 2026.

  2. Luke Miels becomes GSK CEO

    Corporate

    Former Chief Commercial Officer takes the helm, inheriting challenge of offsetting looming patent losses on HIV blockbuster dolutegravir.

  3. RAPT initiates prestIgE Phase 2b trial

    Clinical

    Randomized, double-blind study of ozureprubart in ~100 food allergy patients across US, Canada, and Australia begins enrollment.

  4. GSK announces CEO transition

    Corporate

    Emma Walmsley to step down after nine years; Chief Commercial Officer Luke Miels named successor effective January 2026.

  5. Sanofi announces $9.1B Blueprint Medicines acquisition

    M&A

    French pharma acquires rare immunology specialist, signaling increased Big Pharma appetite for immunology assets.

  6. RAPT Therapeutics raises $150M to fund food allergy program

    Financing

    Post-IPO funding round supports ozureprubart development after company pivoted away from oncology following FDA clinical hold.

  7. FDA approves Xolair for food allergy prophylaxis

    Regulatory

    First medication approved to reduce allergic reactions, including anaphylaxis, from accidental exposure to multiple foods in adults and children age 1+.

  8. Nestlé abandons Palforzia after commercial failure

    Corporate

    Swiss food giant sold the peanut allergy drug to Stallergenes Greer after taking a 1.9 billion Swiss franc impairment charge, three years post-acquisition.

  9. Palforzia becomes first FDA-approved peanut allergy treatment

    Regulatory

    Aimmune Therapeutics' oral immunotherapy approved for ages 4-17. Nestlé completed $2.6 billion acquisition months later.

Scenarios

1

Ozureprubart Succeeds, GSK Captures Best-in-Class Position

Discussed by: Barclays analysts, GSK management guidance, MedCity News

prestIgE Phase 2b data in 2027 demonstrates superior efficacy and confirms the convenience advantage of 12-week dosing. GSK advances to Phase 3 in adult and pediatric populations. By 2030, ozureprubart captures significant market share from Xolair based on patient and physician preference for quarterly injections, generating $1-2 billion in peak annual sales and partially offsetting dolutegravir patent losses.

2

Phase 2b Data Disappoints, GSK Writes Down Investment

Discussed by: Barclays analysts (noting earlier-than-expected stage of asset), biotech investment analysts

Ozureprubart fails to demonstrate meaningful improvement over Xolair in efficacy or differentiation on convenience metrics doesn't translate to superior clinical outcomes. GSK takes an impairment charge similar to Nestlé's $1.9 billion Palforzia writedown, calling into question Miels' early acquisition strategy.

3

Oral Competitors Disrupt the Injectable Market

Discussed by: Northwestern University researchers, Novartis, allergy specialists

Novartis's oral BTK inhibitor remibrutinib advances through trials and demonstrates food allergy protection without injections. Other oral candidates follow. The convenience advantage shifts dramatically to pills over any injectable, leaving both Xolair and ozureprubart competing for a shrinking segment of patients who require or prefer biological therapy.

4

Multi-Player Market Emerges with Room for All

Discussed by: DelveInsight market analysts, pharmaceutical industry observers

With 27 million Americans affected and the market projected to reach $9.2 billion by 2034, multiple therapies coexist based on patient profiles, insurance coverage, and physician preference. GSK's ozureprubart, Roche/Novartis's Xolair, Novartis's remibrutinib, and oral immunotherapy options each carve out distinct niches. The food allergy market follows the pattern of chronic spontaneous urticaria, where multiple biologics compete.

Historical Context

Nestlé's Palforzia Acquisition and Abandonment (2020-2023)

October 2020 - September 2023

What Happened

Nestlé Health Science paid $2.6 billion to acquire Aimmune Therapeutics and its peanut allergy drug Palforzia, the first FDA-approved food allergy treatment. The oral immunotherapy required complex, months-long dosing protocols in clinical settings. Sales never materialized at scale.

Outcome

Short Term

Nestlé took a 1.9 billion Swiss franc impairment charge in early 2023 after conducting a strategic review.

Long Term

Sold Palforzia to Stallergenes Greer in September 2023, demonstrating that first-mover advantage in food allergy doesn't guarantee commercial success if dosing convenience is lacking.

Why It's Relevant Today

GSK is betting that ozureprubart's once-quarterly dosing avoids Palforzia's fundamental problem—that patients and parents won't tolerate inconvenient treatment regimens even for life-threatening allergies.

Pfizer's Anacor Acquisition for Atopic Dermatitis (2016)

May 2016

What Happened

Pfizer paid $5.2 billion for Anacor Pharmaceuticals to acquire crisaborole, a topical treatment for mild-to-moderate eczema. The deal represented Pfizer's bet on the growing immunology/inflammation market and validated the commercial potential of treating allergic conditions.

Outcome

Short Term

Crisaborole (Eucrisa) was approved in 2016 and launched commercially.

Long Term

The eczema market expanded dramatically, with AbbVie's Rinvoq and Sanofi/Regeneron's Dupixent generating billions in sales. Pfizer's bet on the broader allergy/inflammation space proved directionally correct even as specific products faced competition.

Why It's Relevant Today

Shows Big Pharma's long-running appetite for immunology assets at premium prices, and that the competitive landscape in allergy/inflammation markets tends to support multiple successful products.

AstraZeneca's MedImmune Acquisition and Biologics Build-Out (2007)

April 2007

What Happened

AstraZeneca paid $15.6 billion for MedImmune, acquiring the biologics specialist to diversify from small molecules facing patent cliffs. At the time, AstraZeneca was losing exclusivity on blockbusters including Nexium and Seroquel.

Outcome

Short Term

Integration challenges and pipeline setbacks led to writedowns and questions about the deal's wisdom.

Long Term

MedImmune's expertise eventually contributed to AstraZeneca's COVID-19 vaccine development and oncology biologics portfolio. The deal is now viewed as foundational to AstraZeneca's biologics capabilities.

Why It's Relevant Today

GSK faces similar patent cliff pressures with dolutegravir that drove AstraZeneca's MedImmune deal. Big acquisitions to offset revenue loss carry integration risk but can prove transformational over a decade-plus timeframe.

12 Sources:
+6
GSK STAT News BioSpace Pharmaceutical Technology FDA RAPT Therapeutics Food Allergy Research & Education (FARE) Fierce Pharma Sanofi Endpoints News Novartis GSK