In this phase I/II study, we assessed the impact of paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) in the treatment of advanced ovarian carcinoma combined with the standard regimen cisplatin/cyclophosphamide given as follows: paclitaxel 175 mg/m2 (over 3 hours perfusion with standard premedication), cisplatin 80 mg/m2 (6 to 12 hours after paclitaxel), and cyclophosphamide 400 mg/m2. From February 1994 to January 1996, 27 patients (median age, 55 years; age range, 35 to 74 years) were entered into the study. Eight patients had distant metastases and 19 had early locoregional disease (stage III, 18 patients; stage IC, one patient). Twenty-two patients had undergone prior surgery (simple biopsy, six patients; optimally debulked, nine patients; suboptimally debulked, seven patients). Twenty-one patients had received no prior chemotherapy and six were previously treated with at least one platinum-based regimen. A maximum of six courses of paclitaxel/cisplatin/cyclophosphamide were given every 21 days. Twenty-three patients were evaluable for toxicity: neutropenia (World Health Organization grade 3/4), 91% of patients; thrombopenia (World Health Organization grade 3/4), 13% of patients; two episodes of neutropenia with fever; and neurotoxicity grade 3, 17% of patients. Alopecia grade 3 was reported in all patients. No hypersensitivity reactions and no cardiac toxicity was observed. Among 17 patients evaluable for response (patients with stage IV disease or stage III suboptimally debulked), 12 (70%) clinical complete responses (CRs) and three (18%) partial responses were observed. Among the 12 patients with CRs, 10 underwent second-look laparotomy and seven of them (70%) achieved a pathologic CR. In the group of 11 chemotherapy-naive patients evaluable for response, eight (72%) achieved a CR and three (28%) achieved a partial response. This combination seems to be safe, with very acceptable toxicity, and also seems to be highly active in the treatment of patients with advanced ovarian carcinoma.