HER kinase inhibition in patients with HER2- and HER3-mutant cancers

Area of Science:

• Oncology
• Genetics
• Pharmacology

Background:

• Somatic mutations in ERBB2 (HER2) and ERBB3 (HER3) are prevalent across numerous cancer types.
• While some mutations are known to cause constitutive HER2 activation, the biological significance of most remains uncharacterized.
• Preclinical models offer limited insight into the full spectrum of HER2 and HER3 mutation biology.

Purpose of the Study:

• To define the biological and therapeutic importance of known and unknown oncogenic HER2 and HER3 mutations.
• To evaluate the efficacy of the pan-HER kinase inhibitor neratinib in a genomically selected patient cohort.
• To correlate clinical outcomes with specific tumor types and HER2/HER3 mutation profiles.

Main Methods:

• Conducted a multi-histology 'basket' clinical trial (SUMMIT; NCT01953926) using neratinib.
• Enrolled patients with cancers harboring ERBB2 or ERBB3 mutations.
• Analyzed treatment response based on tumor histology and specific mutation characteristics.

Main Results:

• Efficacy of neratinib varied significantly across different cancer types and specific HER2/HER3 mutations.
• Highest therapeutic activity was observed in breast, cervical, and biliary cancers.
• Tumors with kinase domain missense mutations demonstrated notable responses.

Conclusions:

• Molecularly driven basket trials are crucial for elucidating the biological roles of genetic alterations.
• Neratinib shows promise in specific HER2-mutant cancers, particularly those with missense mutations.
• This approach advances the understanding and application of genome-driven oncology.