It is now widely appreciated that patients with metastatic breast cancer whose tumors over express HER-2-neu demonstrate benefit from the addition of trastuzumab (Herceptin) to a chemotherapy program with paclitaxel as a single agent.20 Such patients will be allowed to receive trastuzumab in the standard dose and schedule (4 mg/kg loading dose, then 2 mg/kg/week) given IV, in addition to paclitaxel and vinorelbine. Since trastuzumab does not produce myelosuppression or neuropathy (the anticipated dose-limiting toxicities for vinorelbine and paclitaxel, respectively), and neither of these agents combined separately with trastuzumab produces unusual or severe new side effects, this should not affect the dose escalation scheme for the chemotherapeutic agents.