Ivonescimab cuts death risk 34% in lung cancer trial

A China-made lung cancer drug delivered the strongest survival signal yet for a new PD-1/VEGF class, pressing the case that Chinese biotech can compete with Western drugmakers in one of oncology’s biggest markets. The data also sharpened a long-running dispute over whether the result will travel beyond China, where the trial was run.

Ivonescimab, developed by Akeso and licensed outside China to Summit Therapeutics, cut the risk of death by 34% in the phase 3 HARMONi-6 study in advanced squamous non-small cell lung cancer. The late-stage trial enrolled 532 previously untreated patients with stage IIIB-IV disease in China and compared ivonescimab plus carboplatin and paclitaxel with tislelizumab plus the same chemotherapy backbone, followed by maintenance treatment for up to 24 months.

At the American Society of Clinical Oncology annual meeting in Chicago, the study was presented as the first large prospective trial to show that an anti-PD-1/VEGF bispecific plus chemotherapy beat the standard PD-1 inhibitor-plus-chemotherapy approach in this hard-to-treat lung cancer subtype. After a median follow-up of 21.4 months, median overall survival was about 28 months with ivonescimab versus about 24 months with tislelizumab. The overall survival result carried a p-value of 0.0017, comfortably inside the prespecified boundary of 0.0049.

That statistical margin matters because the drug’s earlier China-only data had already shown a progression-free survival advantage, but had not yet answered the central question of whether patients lived longer. Critics have focused on the trial’s geography, arguing that a China-only design leaves open whether the benefit will hold in broader populations with different genetics, treatment access and disease patterns. Dr. Suresh Ramalingam of Winship Cancer Institute of Emory University called the result very encouraging, while also flagging the question of how well the findings apply outside China. David Spigel of Sarah Cannon Research Institute said the data point to a vital new path forward for difficult cancers.

The commercial stakes are large. Ivonescimab targets both PD-1 and VEGF, a combination some oncologists and investors see as a possible successor to checkpoint blockbusters such as Merck’s Keytruda, while others warn the class could disappoint. ASCO estimated squamous NSCLC affects about 55,000 people in the United States and 2.1 million worldwide each year, underscoring the size of the prize if the regimen succeeds globally. Summit is running a separate phase 3 study outside China, and the market will be watching whether the Chinese result becomes a template for broader approval or a regional exception.