Our Take
GSK is buying clinical-stage assets with FDA approvals coming this year, not a pipeline bet—the payoff is immediate if both drugs clear review.
Why it matters
Oncology M&A is shifting toward rare, genetically-defined lung cancers where resistance mutations create unmet need. GSK fills a gap in its cancer franchise ahead of HIV blockbuster patent cliffs in 2028–2030.
Do this week
Oncology investors: track FDA decisions on zidesamtinib (Sept 18) and eladalkib (Nov 27) to test GSK's integration thesis and peak sales credibility before deal closure in Q3 2026.
GSK Pays $10.6B for Two Near-Approval Lung Cancer Drugs
GlaxoSmithKline has agreed to acquire Nuvalent for $10.6 billion in an all-cash tender offer at $124 per share, a 40% premium to the last closing price. The deal is expected to close in Q3 2026. GSK will acquire Nuvalent's pipeline of three non-small cell lung cancer (NSCLC) treatments, two of which are under FDA review.
The lead assets are zidesamtinib (NVL-520), a ROS1 inhibitor targeting treatment-resistant ROS1-mutant NSCLC, with an FDA decision target of September 18. The second is eladalkib (NVL-655), an ALK inhibitor for ALK-driven tumors that have developed resistance to first-, second-, and third-generation ALK inhibitors, with an FDA decision target of November 27 (per the companies' announcement). Both drugs have been granted Breakthrough Therapy and Orphan Drug designations. A third asset, NVL-330, a HER2 inhibitor, is in Phase I trials for HER2-altered NSCLC.
Both lead candidates are brain penetrant and designed to avoid off-target inhibition of the tropomyosin receptor kinase (TRK) family, which can cause central nervous system adverse events. Zidesamtinib addresses the G2032R "solvent front" resistance mutation in ROS1-mutant NSCLC. Eladalkib targets compound ALK mutations including G1202R.
GSK will fund the acquisition through new and existing debt facilities plus cash, with no expected impact to its credit rating. The company ended Q1 with £3.442 billion in cash. Nuvalent has 228 full-time employees, 144 of whom work in R&D (per company Form 10-K filing).
Peak Sales Projections and Timing
Nuvalent projected that its ROS1+ NSCLC treatment could generate $1.4 billion to $2.1 billion in peak year sales, with approximately 40% from the U.S. market (company projection from May 2025 investor presentation). This would exceed Xalkori (crizotinib), the first-generation ROS1 inhibitor marketed by Pfizer and Merck KGaA, which achieved approximately $150 million in peak year sales (company-reported 2019 figure).
The ALK+ NSCLC opportunity is larger: Nuvalent projected worldwide peak year sales of $3.4 billion to $5 billion, of which 40% would come from the U.S. market (approximately $1.35 billion to $2 billion). This exceeds Alecensa (alectinib), the third-generation ALK inhibitor marketed by Genentech, which achieved $519 million in peak sales in 2023 (company-reported).
GSK expects the acquisition to contribute to revenue growth from 2027 and to be incremental to the company's existing ambition for sales exceeding £40 billion by 2031. The company expects the deal to add to core operating profit in 2027 and core earnings per share in 2029, despite low single-digit percentage EPS dilution through 2028. The deal does not change GSK's 2026 full-year guidance of 7–9% core operating profit and core EPS growth.
Why GSK Bought Now
GSK CEO Luke Miels said the deal follows the company's approach to "acquire assets that have clinically proven targets and meaningfully address an efficacy and/or tolerability gap." Both drugs address resistance mutations in patient populations where current treatments have lost effectiveness.
The timing is strategic for GSK. The company faces patent cliffs on its HIV blockbuster dolutegravir (marketed as Tivicay and in combination therapies Dovato and Juluca) in 2028–2030. GSK holds a 78.3% stake in Viiv Healthcare, which markets dolutegravir (per company disclosure). Nuvalent's near-term revenue could offset profit pressure during this period.
GSK also plans to pair the two ROS1 and ALK inhibitors with its own pipeline asset Ris-Rez, a B7-H3 targeted antibody-drug conjugate now in Phase III development, to build a broader lung cancer platform. ROS1- and ALK-altered NSCLC affect primarily non-smoking adults aged 40–50, a genetically-defined population the companies describe as uniquely engaged.
Nuvalent shares jumped 39% on Nasdaq to $123.25. GSK shares dipped 0.5% on the London Stock Exchange. The $10.6 billion acquisition ranks as the third-largest M&A deal announced this year, behind CVC Capital Partners and Groupe Bruxelles Lambert's €10.7 billion buyout offer for Recordati and Sun Pharmaceutical Industries' $11.75 billion acquisition of Organon.
Nuvalent will assume existing low-single-digit royalty obligations to Royalty Pharma (which acquired a pre-existing royalty interest in both lead drugs for up to $315 million in December 2024) and Deerfield, its largest shareholder.