In brief
- Akeso has announced that ivonescimab monotherapy produced a statistically significant improvement in overall survival compared with pembrolizumab monotherapy in the phase III HARMONi-2 trial, in patients with locally advanced or metastatic PD-L1-positive NSCLC.
- Overall survival was a secondary endpoint, and this was a preplanned analysis of it. Summit’s release carries no hazard ratio, no median survival times and no confidence intervals for the survival result.
- HARMONi-2 is a single-region, multi-centre trial conducted in China and sponsored by Akeso, which generated, managed and analysed all the data.
- The primary analysis of progression-free survival by independent radiologic review gave a hazard ratio of 0.51 (95% CI 0.38 to 0.69) and was published in The Lancet in 2025.
- Results are scheduled for presentation at a medical conference that Summit’s release does not name. Ivonescimab was first approved in China in May 2024, and remains investigational in the United States and Europe.
Study at a glance
- Source trial: HARMONi-2 (AK112-303), randomised, double-blind, phase III, sponsored by Akeso
- Geography: single-region, multi-centre, conducted in China
- Population: locally advanced or metastatic NSCLC with positive PD-L1 expression
- Patients randomised: 398 (Xiong et al., Lancet 2025;405:839-849)
- Comparison: ivonescimab monotherapy against pembrolizumab monotherapy
- Endpoint reported: overall survival, a secondary endpoint, in a preplanned analysis
- Not in Summit’s release: hazard ratio, medians, confidence intervals, follow-up time, safety data from this analysis
- Primary endpoint, reported earlier: progression-free survival by independent radiologic review, hazard ratio 0.51 (95% CI 0.38 to 0.69)
- Regulatory status: first approved in China in May 2024, with NMPA authorisation on the basis of HARMONi-2 in April 2025; investigational in the United States and Europe
A preplanned analysis of a secondary endpoint, announced without figures
Overall survival was a secondary endpoint in HARMONi-2, and the analysis was preplanned rather than post-hoc. That distinction matters for how the statistical claim should be read, since an analysis specified in advance is held to the protocol’s own terms rather than chosen after the data were seen.
What Summit’s release does not carry is any number. There is no hazard ratio, no median overall survival for either group, no confidence interval and no follow-up time. Whether the survival difference is a matter of weeks or of many months cannot be established from what has been released, and the size of an effect is what determines its clinical weight. The release states that the results are scheduled for presentation at an upcoming medical conference, and does not name it.
The primary progression-free survival analysis gave a hazard ratio of 0.51
The primary analysis of HARMONi-2 reported a statistically significant improvement in progression-free survival by independent radiologic review committee, with a hazard ratio of 0.51 (95% CI 0.38 to 0.69). Those results were published in The Lancet in 2025 (Xiong A, Wang L, Chen J, et al. 2025;405:839-849). Ivonescimab was first approved in China in May 2024, and China’s National Medical Products Administration granted marketing authorisation on the basis of HARMONi-2 in April 2025.
A progression-free survival result does not establish a survival benefit, which is the reason a preplanned overall survival analysis is reported separately at all. What the release states about that analysis is its direction and its statistical significance, and nothing about its magnitude.
A single-region trial, with the drug still investigational outside China
HARMONi-2 was conducted entirely in China, and the release states that Akeso exclusively generated, managed and analysed all the relevant data. Summit Therapeutics is running HARMONi-7, a phase III trial of ivonescimab monotherapy against pembrolizumab monotherapy in first-line metastatic NSCLC with high PD-L1 expression, which puts a similar comparison to a separate patient population.
Ivonescimab is a bispecific antibody that blocks PD-1 and VEGF in a single molecule. It is approved and commercially available in China for indications in NSCLC, and it has no regulatory approval in the United States or Europe.
Sources
- Summit Therapeutics. Ivonescimab Monotherapy Demonstrates Statistically Significant Overall Survival Benefit Compared to Pembrolizumab Monotherapy in PD-L1-Positive Advanced NSCLC in HARMONi-2 Study Conducted by Akeso in China (2026-09-02). smmttx.com
- Merck & Co. Summit, Akeso’s ivonescimab bests Merck’s Keytruda in China trial—again (2026-09-03). news.google.com
- Merck & Co. Summit’s Ivonescimab Beats Merck’s Keytruda on Survival in Chinese Lung Cancer Trial (2026-09-03). news.google.com
This article was produced independently by the Lung Summit editorial team, without industry funding or input.
