Phase Ia Study of Novel Anti-HER2 Antibody-Drug Conjugate GQ1001 Shows Promise in Treating HER2 Positive Advanced Solid Tumors

Study Overview

A phase Ia, first-in-human, multi-center, open-label study was conducted to evaluate the safety, pharmacokinetics (PK), and preliminary anti-tumor activity of GQ1001 in patients with HER2 positive advanced solid tumors. The study involved patients from Australia, the United States, and China, all of whom had previously treated, advanced solid tumors that were HER2 positive.

Methodology

Patients were treated with GQ1001 in a dose-escalation manner, starting from 1.2 mg/kg up to 8.4 mg/kg, administered intravenously every three weeks. The study employed a modified 3 + 3 design to determine the maximum tolerated dose (MTD) and the dose recommended for dose expansion (DRDE). Safety and efficacy were assessed through various endpoints, including the incidence of dose-limiting toxicities (DLTs), adverse events (AEs), and objective response rate (ORR).

Results

No DLTs were observed up to the highest dose of 8.4 mg/kg, and the MTD was not reached. Treatment-related adverse events (TRAEs) occurred in 75% of patients, with the most common being increased aspartate aminotransferase, decreased platelet count, and increased alanine aminotransferase. The study determined 8.4 mg/kg as the DRDE based on safety profiles.

Preliminary anti-tumor activity was observed, with an ORR of 40.0% in the high-dose cohorts (7.2 mg/kg and 8.4 mg/kg). The median progression-free survival (PFS) was 6.5 months, indicating promising efficacy of GQ1001 in treating HER2 positive advanced solid tumors.

Conclusion

The phase Ia study of GQ1001 demonstrated its excellent tolerability and promising anti-tumor efficacy in patients with heavily treated HER2 positive advanced solid tumors. The safety and efficacy profiles of GQ1001, attributed to its innovative conjugation technology, warrant further evaluation in larger trials to confirm its potential as a treatment option for HER2 positive cancers.