依沃西单药 HARMONi-2 头对头胜 Keytruda：中位总生存 30.8 对 22.6 个月、死亡风险降 27%，但系 9 月 3 日已公告中期 OS 阳性的 WCLC 完整数据披露，非新催化

Summit Therapeutics (SMMT) on Sunday said ivonescimab significantly extended survival compared with Merck’s (MRK) Keytruda in a late-stage lung cancer trial conducted by its partner Akeso (AKESF) in China.
Ivonescimab reduced the risk of death by 27% compared with Keytruda, also known as pembrolizumab, among previously untreated patients with advanced non-small cell lung cancer whose tumors expressed PD-L1.
Median overall survival reached 30.8 months for patients receiving ivonescimab, compared with 22.6 months for the Keytruda group. The 8.2-month difference was statistically significant, Summit said.
The Phase 3 HARMONi-2 trial enrolled 398 patients and had a median follow-up period of 36 months. Results are being presented at the International Association for the Study of Lung Cancer’s World Conference on Lung Cancer in Seoul.
For investors, the survival advantage strengthens the case that ivonescimab could compete with Keytruda, one of the world’s best-selling medicines. It also validates Summit’s (SMMT) decision to license the drug outside China and fund a broad global development program.
However, the findings came from a China-only study. Summit (SMMT) still must show comparable results in international trials before securing approval in the United States and Europe. The company’s shares are little changed this year, suggesting investors remain focused on regulatory execution and confirmation of the drug’s benefits in a broader patient population.
Ivonescimab appeared particularly effective in patients with high PD-L1 expression, reducing the risk of death by 42%. That subgroup included 168 patients.
The survival benefit was smaller among patients with lower PD-L1 expression. Ivonescimab produced a hazard ratio of 0.85 in that group, with a confidence interval that crossed 1.0. That means the study did not establish a statistically reliable survival advantage for those patients.
The subgroup analyses were descriptive and were not designed to provide definitive statistical conclusions.
Summit (SMMT) is now recruiting patients for HARMONi-7, a global Phase 3 trial comparing ivonescimab with Keytruda in patients whose tumors have high PD-L1 expression. The study is expected to enroll 780 patients, with progression-free survival and overall survival as its primary measures.
Serious treatment-related adverse events occurred in 29.9% of patients receiving ivonescimab, compared with 21.6% of those receiving Keytruda.
Despite the higher rate of serious events, treatment discontinuations were slightly less frequent with ivonescimab, affecting 4.1% of patients compared with 5% in the Keytruda arm. Summit (SMMT) said no new safety concerns emerged during the longer follow-up period.
Ivonescimab combines two cancer-fighting mechanisms in one antibody. It blocks PD-1 to help the immune system attack tumors while also targeting VEGF, a protein that promotes blood-vessel growth around tumors.
The drug is approved and commercially available in China but remains experimental in Summit’s (SMMT) territories, which include the United States, Europe and Japan. Summit has submitted a separate application to the Food and Drug Administration for ivonescimab in previously treated EGFR-mutated lung cancer. The agency has set a Nov. 14 decision deadline.