Ivonescimab, a PD-1/VEGF bispecific antibody from Summit Therapeutics and Akeso, improved overall survival over pembrolizumab in the Phase III HARMONi-2 trial in first-line Chinese patients with PD-L1–positive advanced NSCLC, hitting a key secondary endpoint at a pre-specified interim analysis. The study follows previously reported HARMONi-2 progression-free survival data showing a 49% reduction in the risk of progression or death versus pembrolizumab, with full OS figures still pending presentation at a future medical meeting.

Why It Matters To Oncology

• HARMONi-2 is one of the clearest late-stage signals yet that dual PD-1/VEGF blockade may outperform PD-1 monotherapy in frontline PD-L1–positive NSCLC.

• The result builds on prior PFS superiority versus pembrolizumab and raises the competitive bar in immuno-oncology drug discovery beyond checkpoint inhibition alone.

• Ivonescimab is already approved in China for first-line PD-L1–positive NSCLC without EGFR or ALK mutations based on the HARMONi-2 PFS data.

The Financials

• Summit's shares previously more than tripled after the company first said HARMONi-2 met its primary PFS endpoint.

• The new OS win strengthens the asset's commercial positioning against Merck's Keytruda franchise, even though the companies have not yet disclosed the survival magnitude.

• A separate FDA decision is due by Nov. 14 on ivonescimab plus chemotherapy in EGFR-mutated non-squamous NSCLC after progression on an EGFR TKI.

What They're Saying

• Summit and Akeso said HARMONi-2 showed a statistically significant and clinically meaningful OS improvement over pembrolizumab at interim analysis.

• They have not released the hazard ratio or median OS figures yet, signaling that the most important details for clinicians will likely come at a future conference presentation.

• In the separate Phase III HARMONi study, Summit has highlighted maturing OS data after an initial positive trend missed significance at primary analysis (HR 0.79, p=0.057), later strengthening with follow-up (HR 0.78, p=0.0332; then HR 0.76 in a subsequent analysis).

What's Next

• Clinicians will be watching for the full HARMONi-2 OS dataset, including hazard ratio, median follow-up, subgroup effects, and safety context versus pembrolizumab.

• Summit is running the global Phase III HARMONi-7 trial across the U.S., Europe, and other regions to test whether the HARMONi-2 signal replicates beyond Chinese patients, especially in PD-L1 high-expressing NSCLC.

• For drug discovery teams, the bigger question is whether ivonescimab can validate bispecific PD-1/VEGF biology as a scalable platform strategy across lung cancer settings.