KangFang Bio-ivonescimab Phase III Trial: Lung Cancer Overall Survival Exceeds Standard Immunotherapy
0xBroomberg
Akeso's bispecific antibody ivonescimab cut the risk of death by 34% in advanced squamous lung cancer, marking the first Chinese-developed oncology drug presented at ASCO's plenary — a direct challenge to the multibillion-dollar PD-1 market.
What did this trial actually test?
Akeso's HARMONi-6 Phase III trial enrolled 532 patients with advanced squamous non-small-cell lung cancer and compared ivonescimab plus chemotherapy head-to-head against tislelizumab plus chemotherapy — an already-approved immunotherapy regimen.
In plain terms = the comparison was not against "no treatment" but against one of the current best options. That is what makes the result meaningful.
The data were presented at the ASCO annual meeting plenary and simultaneously published in *The Lancet* — a first for any Chinese-developed oncology drug.
How much longer did patients live?
Median overall survival: 27.9 months for ivonescimab vs 23.7 months for the control — a 34% reduction in the risk of death.
Two-year survival rate: 64.7% vs 48.6%. This means → out of every 100 patients, roughly 16 more were alive at the two-year mark.
The survival benefit held across multiple subgroups, including patients with low PD-L1 expression and heavier metastatic burden. Put simply = the drug did not only work in a narrow, cherry-picked population.
Can patients tolerate the side effects?
Grade ≥3 treatment-related adverse events: 69.2% in the ivonescimab arm vs 58.9% in the control — toxicity was genuinely higher.
Yet treatment discontinuation rates and treatment-related death rates were comparable between the two arms. This means → more side effects occurred, but the rate of events severe enough to stop therapy or cause death did not meaningfully increase.
Progression-free survival also favored ivonescimab: 11.1 months vs 6.9 months.
Why did this drug win?
Ivonescimab is a PD-1/VEGF bispecific antibody — a single molecule that blocks two targets at once: immune-checkpoint evasion and tumor blood-vessel growth.
In plain terms = a standard PD-1 drug blocks one escape route; ivonescimab blocks two — the tumor can neither "hide" from the immune system nor "build its own supply lines."
This reflects a real-world validation that the bispecific design has moved beyond theory into hard survival data in lung cancer.
What does this mean for the market?
The global PD-1/PD-L1 lung-cancer immunotherapy market is worth tens of billions of dollars, dominated by Merck, Bristol-Myers Squibb, and other large-cap pharma players.
A head-to-head trial against an approved regimen with a positive outcome gives ivonescimab the strongest possible clinical evidence for market entry. This means → the regulatory and commercial path just became significantly clearer.
Akeso's partner Summit Therapeutics holds development rights for ivonescimab outside China. The drug is currently being studied in over 30 clinical programs, including 15 Phase III trials.
Content is for reference only, not financial advice.