Ivonescimab combined with chemotherapy in patients with EGFR-mutant non-squamous non-small cell lung cancer who progressed on EGFR tyrosine-kinase inhibitor treatment (HARMONi-A): A randomized, double-blind, multi-center, phase 3 trial.

Abstract

8508 Background: Ivonescimab (AK112/SMT112) is a anti-PD-1/VEGF bispecific antibody. Previous phase I/II clinical studies have shown potential efficacy of ivonescimab in NSCLC patients with EGFR mutations who had failed prior EGFR-TKIs therapies. This phase 3 study aimed to evaluate and confirm the efficacy and safety of ivonescimab combined with chemotherapy versus chemotherapy alone in this population. Methods: Patients were randomized 1:1 to receive ivonescimab (20 mg/kg) plus pemetrexed (500 mg/m2) and carboplatin (AUC 5) or placebo plus chemotherapy once every 3 weeks for four cycles, with stratification according to the third-generation EGFR-TKI (received vs not received) and brain metastases (presence vs absence), followed by maintenance therapy of ivonescimab and pemetrexed or placebo and pemetrexed. The primary endpoint was progression-free survival (PFS) in intention-to-treat (ITT) population assessed by independent radiographic review committee (IRRC) per RECIST v1.1. Here we report the results of the first planned interim analysis. Results: Total 322 patients were randomized (161 to the ivonescimab plus chemotherapy arm, 161 to the placebo plus chemotherapy arm). 86.3% versus 85.1% of patients had received the third generation EGFR-TKIs treatment, 21.7% versus 23.0% of patients had brain metastases. As of March 10, 2023, median follow up time was 7.89 months. PFS was significantly improved in the ivonescimab plus chemotherapy arm (HR 0.46 [0.34, 0.62], P < 0.0001). Median PFS (95%CI) by IRRC were 7.06m (5.85, 8.74) in the ivonescimab arm versus 4.80m (4.21, 5.55) in chemotherapy arm. The prespecified subgroup analysis showed PFS benefit favoring patients receiving ivonescimab over placebo across almost all subgroups, including in patients who progressed on the third-generation EGFR-TKIs therapy (HR 0.48, 95% CI 0.35-0.66), those with brain metastases (HR 0.40, 0.22-0.73), those with EGFR mutation of deletion 19 (HR 0.48, 0.32-0.73), and individuals with T790M mutation positive (HR 0.22, 0.09-0.54). The ORR were 50.6% and 35.4%, respectively. Grade ≥3 TEAEs occurred in 99 (61.5%) patients versus 79 (49.1%) patients, the most common grade ≥3 TEAEs were chemotherapy related adverse events. Grade ≥3 immune-related adverse events occurred in 10 (6.2%) patients versus 4 (2.5%). Grade ≥3 VEGF blocking related adverse events occurred in 5 patients (3.1%) versus 4 patients (2.5%). Conclusions: Ivonescimab plus chemotherapy significantly improved PFS while maintaining a manageable safety profile in patients who had failed EGFR-TKIs treatments. Clinical trial information: NCT05184712 .