Category: pharmacological
Aliases: Herceptin
Humanized anti-HER2 (ERBB2) IgG1 monoclonal antibody. Binds the juxtamembrane domain IV of HER2 — blocks ligand-independent dimerization, induces ADCC, internalizes the receptor. Indications: HER2-positive breast cancer (adjuvant, metastatic, neoadjuvant) and HER2-positive gastric/GEJ cancer. Cardiotoxicity risk especially when combined with anthracyclines (synergistic reduction in EF). Biologic PK — long t½ ~28 days at steady state, IgG salvage clearance. PK (Bruno 2005 popPK PMID:15868146 + Herceptin label): IV-only mAb. Two-compartment model with parallel linear + nonlinear elimination; linear clearance dominates during chronic dosing. CL 0.173-0.337 L/day (typical 0.225 L/day) similar to other IgG1 mAbs. V1 (central) 2.95 L. Terminal t½ 28.5 days. Steady state ~12 weeks for weekly or q3-week regimens. Covariates: body weight, AST, albumin, gastric primary, liver mets. Cardiotoxicity not PK-related (HER2-pathway target on cardiomyocytes).
IV: 684h, SC: 684h