Components:
- T: Docetaxel — taxane chemotherapy agent
- C: Carboplatin — platinum-based chemotherapy
- H: Trastuzumab — HER2-targeted monoclonal antibody
- P: Pertuzumab — HER2-targeted monoclonal antibody, complementary to trastuzumab
Indications:
- Used for HER2-positive early-stage and locally advanced breast cancer in the neoadjuvant and adjuvant settings.
- Improves pathologic complete response rates and disease-free survival compared to TCH alone.
Mechanism of Action:
- Docetaxel: Stabilizes microtubules, blocking mitosis.
- Carboplatin: Causes DNA crosslinking, inducing apoptosis.
- Trastuzumab: Binds HER2 receptor, inhibiting downstream signaling and mediating ADCC.
- Pertuzumab: Binds a different HER2 domain, preventing dimerization with other HER family receptors, enhancing HER2 blockade synergistically with trastuzumab.
Administration:
- Usually given intravenously every 3 weeks for 6 cycles.
- Trastuzumab and pertuzumab are continued to complete 1 year of HER2-targeted therapy.
Key Toxicities:
- Neutropenia, anemia, thrombocytopenia
- Peripheral neuropathy (docetaxel)
- Cardiotoxicity (monitor LVEF regularly for trastuzumab and pertuzumab)
- Infusion-related reactions
- Electrolyte abnormalities (carboplatin)
Pharmacist Considerations:
- Monitor CBC and manage myelosuppression.
- Baseline and periodic cardiac function monitoring.
- Pre-medicate and monitor for hypersensitivity reactions.
- Counsel patients on side effects and importance of adherence to HER2 therapy.