Pemetrexed is a multi-targeted anti-folate, that is used for non-small cell lung cancer and mesothelioma. There are several clinical studies of pemetrexed in breast cancer, but these are largely done before the wide use of premedication (steroid and vitamin B12) for pemetrexed. Moreover, it has not been studied in combination with vinorelbine, which is a commonly used drug for anthracycline- and taxane-pretreated metastatic breast cancer.