Treating Advanced Unresectable or Metastatic HER2-Positive Breast Cancer: A Spotlight on Tucatinib

Area of Science:

• Oncology
• Pharmacology

Background:

• HER2 positive breast cancer management has advanced significantly with targeted therapies.
• Trastuzumab, pertuzumab, and T-DM1 are current standards of care for advanced stages.
• Limited effective options existed for third-line and beyond therapy previously.

Purpose of the Study:

• To review the efficacy and safety of novel agents for advanced HER2 positive breast cancer post-T-DM1.
• To focus on tyrosine kinase inhibitors, specifically tucatinib, in the post-T-DM1 setting.

Main Methods:

• Review of clinical trial data for tucatinib and trastuzumab deruxtecan.
• Analysis of efficacy and toxicity profiles of new agents.
• Focus on tyrosine kinase inhibitors in the post-T-DM1 treatment landscape.

Main Results:

• Tucatinib, a third-generation HER2 tyrosine kinase inhibitor, shows efficacy comparable to neratinib but with better tolerability.
• Trastuzumab deruxtecan demonstrated significant efficacy in heavily pre-treated patients.
• Tucatinib is now a standard of care after T-DM1, combined with capecitabine and trastuzumab.

Conclusions:

• Tucatinib represents a new standard of care for HER2 positive breast cancer after T-DM1.
• Novel agents like tucatinib and trastuzumab deruxtecan are improving outcomes for heavily pre-treated patients.
• Further data on trastuzumab deruxtecan is pending confirmatory trials.