Cardiotoxicity, enhanced in combination with anthracyclines such as doxorubicin
“Preclinical studies have been undertaken in an attempt to elucidate the mechanism for the enhanced cardiotoxicity observed in some clinical-trial patients receiving trastuzumab in combination with an anthracycline-based cytotoxic such as doxorubicin.”
1/84 monkeys in repeat-dose studies; neutralising antibodies in one low-dose cynomolgus female (weeks 5-26)
“Neutralising antibodies were detected from weeks 5-26 in one low-dose female cynomolgus monkey. This represents an incidence of 1/84 animals in repeated-dose studies in which antibodies to trastuzumab were detected.”
Anti-trastuzumab antibodies (HAHA) in 1 of 903 women with metastatic breast cancer; no allergic reaction
“Among 903 women with metastatic breast cancer, human anti human antibody (HAHA) to Herceptin was detected in one patient using an enzyme linked immunosorbent assay (ELISA). This patient did not experience an allergic reaction.”
In vitro whole-blood cytokine release far below alemtuzumab/TGN1412 controls; no effects on monkey TDAR, lymphocyte subsets or serum cytokines; ADA in some monkeys