Shares shifted as Summit Therapeutics surged 6.1% to $18.59 on a down day for the broader market, powered by data showing its partner Akeso's experimental cancer drug helped patients with advanced lung cancer live 8.2 months longer than those receiving Merck's blockbuster treatment pembrolizumab. For a company that has never booked a dollar of revenue, the question is whether this clinical victory can eventually translate into commercial returns that justify a market value already north of $13 billion.
• The Drug Outperformed the World's Top-Selling Cancer Medicine — And It Wasn't Close
Results showed that ivonescimab significantly prolonged overall survival in patients with PD-L1-positive advanced lung cancer compared with pembrolizumab. Median survival reached 30.8 months versus 22.6 months, with a hazard ratio of 0.73 (meaning a 27% reduction in risk of death) and a p-value of 0.009, clearing the bar for statistical significance. The survival benefit was generally consistent across subgroups, with particularly pronounced benefit in patients with high PD-L1 expression. That consistency matters because regulators want to see a drug work broadly, not just in cherry-picked patients.
• Summit Is Trying to Dethrone a $32 Billion Franchise
Pembrolizumab's 2024 global revenue exceeded $29 billion, and 2025 sales tracked toward $32 billion.
The drug is slated for a loss of exclusivity in 2028, and a growing pipeline of biosimilars is already lining up. That looming patent cliff creates a rare opening. If ivonescimab can prove itself outside China — where it received marketing authorization in May 2024 — even a small slice of pembrolizumab's market would dwarf Summit's current valuation.
• The FDA Decision Deadline Looms in Just Two Months
The FDA provided a PDUFA goal action date of November 14, 2026 , for a separate application covering ivonescimab combined with chemotherapy in a different lung-cancer setting. Over 14,000 U.S. patients are eligible for treatment each year in that setting alone. An approval would mark Summit's first-ever product on the U.S. market.
• The Valuation Bakes In a Lot of Hope — With Real Risks Attached
Summit has no revenue, deeply negative margins, and return on equity below negative 200%.
The company plans a $500 million stock offering, plus a $75 million greenshoe option, to fund operations — diluting existing shareholders. Today's data strengthens the drug's scientific case, but investors are still betting on a company whose entire future rides on one medicine across every trial in its pipeline. The survival data is impressive; whether it's impressive enough to sustain a $13 billion bet remains the open question.