Ivonescimab Tops Pembro in Advanced PD-L1-Positive NSCLC

First-line treatment with ivonescimab led to a statistically significant and clinically meaningful improvement in progression-free survival (PFS) compared with pembrolizumab (Keytruda) in patients with PD-L1-positive advanced non-small cell lung cancer (NSCLC), according to recent findings from the HARMONi-2 trial. 

“This is the first randomized, phase 3 study to demonstrate a clinically significant improvement in efficacy with a novel drug compared to pembrolizumab in advanced NSCLC,” said study investigator Caicun Zhou, MD, PhD, with Shanghai Pulmonary Hospital in Shanghai, China, 

The results highlight ivonescimab’s potential to become a “new standard of care” in advanced PD-L1-positive advanced NSCLC, said Zhou, who presented the analysis at the IASLC 2024 World Conference on Lung Cancer in San Diego. Zhou is president-elect of the IASLC. 

Ivonescimab (AK112) is a novel, potentially first-in-class investigational bi-specific antibody that targets programmed death 1 (PD-1) and vascular endothelial growth factor (VEGF) developed by Akeso Biopharma, which funded the HARMONi-2 trial. 

Conducted at 55 centers in China, HARMONi-2 enrolled 398 patients with untreated locally advanced or metastatic NSCLC, Eastern Cooperative Oncology Group (ECOG) Performance Status of 0 or 1, PD-L1 positive (with at least 1% of tumor cells expressing PD-L1) and no EGFR mutations or ALK rearrangements.

Patients were randomly allocated (1:1) to receive ivonescimab (20 mg/kg) or pembrolizumab (200 mg) every 3 weeks. The two groups were well balanced, and randomization was stratified by histology (squamous vs non-squamous), clinical stage (IIIB/IIIC vs IV) and PD-L1 expression (PD-L1 of 1% to 49% vs 50% or greater). 

Zhou reported that patients who received ivonescimab were progression-free for nearly twice as long as those on pembrolizumab — a median of 11.1 vs 5.8 months, indicating a 49% lower risk for progression or death (stratified hazard ratio [HR], 0.51; P

The meaningful improvement in PFS with ivonescimab, compared with pembrolizumab, was “broadly consistent” in all prespecified subgroups, Zhou noted. That included patients with squamous NSCLC (HR, 0.48) and non-squamous NSCLC (HR, 0.54), those with PD-L1 expression of 1% to 49% (HR, 0.54) and 50% or higher (HR, 0.46), as well as those with liver metastases (HR, 0.47) and brain metastases (HR, 0.55). 

The PFS benefit seen with ivonescimab in HARMONi-2 is “striking,” and the results “highlight the potential benefits of combined VEGF and PD-1 blockade together,” said John Heymach, MD, with MD Anderson Cancer Center in Houston, Texas, who served as discussant for the study. 

Ivonescimab also led to a higher objective response rate (50% vs 38.5%) and disease control rate (89.9% vs 70.5%). 

Grade 3 or higher treatment-related adverse events occurred in more patients receiving ivonescimab — 29.4% vs 15.6% on pembrolizumab. The difference largely stemmed from higher rates of proteinuria, hypertension, and lab abnormalities.

The rates of serious treatment-related adverse events were similar between the groups —20.8% in the ivonescimab group and 16.1% in the pembrolizumab group. Rates of grade 3 or higher immune-related adverse events were also similar, occurring in 7% of patients treated with ivonescimab and 8% of those receiving pembrolizumab. 

In patients with squamous cell carcinoma, in particular, ivonescimab demonstrated a “very manageable” safety profile, Zhou noted. In this group, grade 3 or higher treatment-related adverse events occurred in 22.2% of patients (vs 18.7% receiving pembrolizumab).

Ivonescimab was associated with comparable but “numerically better” time to deterioration of global health status, based on the EORTC Core Quality of Life questionnaire, Zhou said. 

Although the “really impressive and clinically meaningful” PFS benefits extended across different subgroups, “we await the overall survival results and additional studies done outside of China to confirm the benefit seen,” Heymach noted.

He also cautioned that for patients with low to intermediate PD-L1 expression (1% to 49%), pembrolizumab monotherapy “would not be the relevant comparator in the US and the rest of the world, and different study designs are going to be required for those populations.”

Based on the results of HARMONi-2, Akeso’s partner, Summit Therapeutics, plans to initiate HARMONi-7 in early 2025. 

HARMONi-7 is currently planned as a multiregional, phase 3 clinical trial that will compare ivonescimab monotherapy to pembrolizumab monotherapy in patients with metastatic NSCLC whose tumors have high PD-L1 expression (50% or more). 

Zhou has received consulting fees from Qilu Pharmaceutical, Hengrui, and TopAlliance Biosciences Inc.; honoraria from Eli Lilly China, Boehringer Ingelheim, Roche, Merck Sharp & Dohme, Qilu, Hengrui, Innovent Biologics, Alice, C-Stone, Luye Pharma, TopAlliance Biosciences Inc., Amoy Diagnostics, and AnHeart Therapeutics. Heymach is a consultant for AbbVie, AnHeart Therapeutics, ArriVent Biopharma, AstraZeneca, BioCurity Pharmaceuticals, BioNTech AG, Blueprint Medicines, Boehringer Ingelheim, BMS, Eli Lilly & Co, EMD Serono, Genentech, GlaxoSmithKline, Janssen Pharmaceuticals, Mirati Therapeutics, Novartis Pharmaceuticals, Regeneron Pharmaceuticals, Sanofi, Spectrum Pharmaceuticals, and Takeda.