GSK Agrees To Buy Nuvalent For $10.6 Billion, Its Biggest Deal In A Decade

In February, GSK's new boss said he would stick to small, quiet deals. Four months later, he is spending billions on one.

What GSK Is Buying

GSK is Britain's second-largest drugmaker. This deal is a big swing for it.

Nuvalent is a small U.S. biotech. That is a firm that makes new medicines.

It works on hard-to-treat lung cancers tied to certain genes. GSK wants that work badly.

Nuvalent is based in the U.S., and its work is still mostly in trials. The two drugs target rare gene types, which sets them apart from older care.

GSK is paying $10.6 billion in cash. That is 40% more than Nuvalent's last stock price.

The buy is all in cash. There is no stock involved.

Investors loved it for Nuvalent, whose shares jumped about 39%. GSK's own stock slipped a bit, which is common when a buyer pays up.

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Why GSK Is Doing This

There is a clock ticking. GSK's top HIV drug starts to lose its patent shield in 2028.

A patent blocks copies of a drug for a set time. When it ends, cheap copycats move in and eat sales fast.

GSK's HIV drug has been a cash machine for years. Losing it would leave a real gap.

For GSK, the goal is simple. Replace old sales with new ones.

Buying Nuvalent helps fill that hole. The deal brings two late-stage lung cancer drugs that could be big sellers.

The two drugs are neladalkib and zidesamtinib. One research group sees their sales near $823 million by 2029.

Lung cancer is one of the deadliest cancers. New drugs that work well can sell big.

It is like fixing the roof before the rain. The HIV money still flows, so GSK lines up its next source early.

What To Watch

The drugs still need a green light. Nuvalent's lead drug faces an FDA call due November 27.

This is GSK's biggest buy in over ten years. The last one bigger was a 2014 swap with Novartis worth about $20 billion.

Boss Luke Miels took over from Emma Walmsley this year. The stock is up about 29% since his hire.

GSK kept its 2026 profit outlook the same. The deal should add to growth from 2027.

GSK has leaned on small deals for years. So this big buy really stands out.

The wave of biotech deals is also growing. About $106 billion has changed hands across 201 deals in 2026 so far.

Barclays likes the deal but is unsure how big the drugs can get. Some cheered the move, while others asked about the price.

GSK promised small deals, but the patent clock changed the plan.

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