Andamertinib in Advanced NSCLC With EGFR Exon 20 Insertions After Platinum-Based Chemotherapy or Immunotherapy: Results From the Phase 2 KANNON Study

Objectives: This study aimed to evaluate andamertinib, a selective and irreversible tyrosine kinase inhibitor, in pretreated advanced EGFR exon 20 insertion (ex20ins)-mutant NSCLC. Methods: In the phase 2, multicenter, single-arm KANNON study (NCT06015503), patients with locally advanced or metastatic NSCLC harboring EGFR ex20ins mutations who had progressed after platinum-based chemotherapy or immunotherapy received oral andamertinib 240 mg once daily in 28-day cycles. The primary end point was the confirmed objective response rate (ORR) assessed by independent review. Results: A total of 92 patients were enrolled and received daily 240 mg andamertinib, with nearly 30 different exon20ins subtypes included. The confirmed ORR was 42.7% (95% confidence interval [CI], 32.4–53.0), with a disease control rate of 86.5% and a median duration of response of 8.7 months (95% CI, 5.65–11.96). As of September 6, 2025, with a median follow-up of 15.4 (range, 0.4–20.5) months, the median progression-free survival was 6.2 months (95% CI, 4.63–7.85) and median overall survival was not reached (95% CI, 13.93 mo to not estimable), with a 12-month survival rate of 70.5%. Among 38 patients with brain metastasis, the systemic confirmed ORR was 47.4% (95% CI, 31.5–63.2). Grade more than or equal to 3 treatment-related adverse events occurred in 40.2% of patients, and the most frequent events were diarrhea (12.0%) and rash (7.6%). No interstitial lung disease or grade more than or equal to 3 QT prolongation was reported. Conclusions: Andamertinib at 240 mg once daily demonstrated efficacy with a manageable safety profile in previously treated patients with EGFR ex20ins-mutant NSCLC.