HER2-Selective Tyrosine Kinase Inhibitor, Zongertinib (BI 1810631), in Patients With Advanced/Metastatic Solid Tumors With HER2 Alterations: A Phase Ia Dose-Escalation Study

Abstract

Purpose: Human epidermal growth factor receptor 2 (HER2) alterations occur in many solid cancers, including non-small cell lung cancer (NSCLC). Beamion LUNG-1 (ClinicalTrials.gov identifier: NCT04886804) is assessing the safety/efficacy of zongertinib (BI 1810631), a novel HER2-selective tyrosine kinase inhibitor that spares epidermal growth factor receptor, in patients with HER2-altered solid tumors.

Materials and methods: Beamion LUNG-1 is an ongoing multicenter, multicohort phase Ia/Ib trial. Phase Ia assessed zongertinib administered twice a day (15-150 mg) or once daily (60-360 mg) in pretreated patients with various tumors, including NSCLC. Primary end points were maximum tolerated dose (MTD) and dose-limiting toxicities (DLTs); tumor response was a secondary end point.

Results: As of May 23, 2024, 105 patients were treated. Two DLTs occurred during the MTD evaluation period; MTD was not reached (NR). The recommended doses for expansion were 120 mg once daily and 240 mg once daily. Treatment-related adverse events (TRAEs; any/grade ≥3) occurred in 82%/10% of patients. The most common TRAEs (any/grade ≥3) included diarrhea (50%/1%), rash (16%/2%), anemia (10%/0%), decreased appetite (10%/1%), and increased alanine transaminase (10%/4%). The confirmed investigator-assessed overall response rate (ORR) across all doses/tumors was 30% (95% CI, 23 to 40); median duration of response was 12.7 months (95% CI, 6.9 to NR). In 54 patients with NSCLC, confirmed ORR was 35% (95% CI, 24 to 49). Activity was observed in patients with A775_G776insYVMA (ORR, 38%) and those who had received previous HER2-directed therapy (ORR, 28%). In patients with NSCLC receiving zongertinib once daily, median progression-free survival was 17.2 months (95% CI, 8.3 to NR).

Conclusion: Zongertinib had a manageable safety profile and demonstrated preliminary antitumor activity in patients with HER2-altered tumors, including those with HER2-mutant NSCLC.

FIG 1.

CONSORT diagram.

FIG 2.

(A) Swimmer plot of response assessments and duration of treatment by patient. (B) Best percentage change from baseline in target lesions according to RECIST version 1.1. Patients with ≥one postbaseline tumor assessment or who discontinued before first postbaseline assessment for any reason. PD, progressive disease; PR, partial response; SD, stable disease.