Experimental Lung Cancer Drug Cuts Death Risk by 34% in China Trial

An experimental lung cancer drug developed by Akeso and Summit Therapeutics reduced the risk of death by 34% in a late-stage trial conducted in China, according to data released Sunday. The drug, ivonescimab, targets both PD-1 and VEGF pathways. In the Harmoni-6 trial, patients who received ivonescimab plus chemotherapy lived a median of 27.9 months versus 23.7 months for those given a standalone PD-1 drug and chemotherapy.

The four-month survival gain marks a measurable step forward for squamous cell lung cancer, a subtype often linked to smoking. Bleeding of any severity occurred in nearly one-quarter of ivonescimab patients, twice the rate seen in the control group, though severe bleeding remained under 3%.

Older VEGF drugs controlled tumors but rarely extended survival, prompting earlier doubts about whether ivonescimab’s benefit would persist. The trial results were presented Sunday at a major oncology meeting.

An associate professor of medicine at the Icahn School of Medicine at Mount Sinai noted the survival difference is neither trivial nor transformative and said its clinical value depends on individual patients. The same physician also pointed out that patients in the control arm lived six months longer than historical expectations, raising questions about how representative the study population was.

Summit Therapeutics plans to release progression-free survival results from its global Harmoni-3 trial for squamous patients in the second half of this year.

Checkpoint inhibitors such as Merck’s Keytruda have transformed lung cancer treatment and generated more than $30 billion in sales last year. Licensing deals for PD-1 drugs reached $30 billion in 2025, nearly double the prior peak. Merck’s head of global oncology clinical development said the company sees room for PD-1/VEGF drugs but does not expect them to replace Keytruda across all indications.