Patients with measurable metastatic or recurrent squamous carcinoma of the uterine cervix who had failed prior surgery or radiation therapy were enrolled on this randomized phase II study. Twenty-seven eligible patients were assigned to receive didemnin B at either 2.6 mg/m2 iv every 28 days (sixteen patients) or at 5.6 mg/m2 (eleven patients). Sixteen patients were assigned to receive 12 mg/m2/day iv trimetrexate for 5 days, repeated every 21 days. Toxicity for didemnin B was characterized by nausea and vomiting (78% of patients), anemia (59%), mild diarrhea (11%), and episodic hypersensitivity (three patients). Toxicity for trimetrexate included nausea and vomiting (69%), leukopenia (51%), mild thrombocytopenia (38%), anemia (63%), and diarrhea (31%). No antitumor responses were observed for either agent. Neither trimetrexate nor didemnin B at these doses and schedules is recommended for the treatment of advanced squamous carcinoma of the uterine cervix.