Background: Because of the relative scarcity of natural paclitaxel (Taxol), which has been recently recognized as a highly cytotoxic agent for use in platinum-refractory ovarian cancer, synthetic and semisynthetic substitutes have been actively pursued. Docetaxel (Taxotere), a new semisynthetic taxoid, has been selected for clinical development because it is twice as potent as paclitaxel in promoting assembly of tubulin and in inhibiting microtubule depolymerization. Docetaxel also shows equal or greater cytotoxicity in relevant preclinical models.
Purpose: Because docetaxel has produced consistent antitumor responses in ovarian cancer patients in phase I trials, we planned and conducted a phase II clinical trial to evaluate the drug's effectiveness and its toxic effects.
Methods: The present trial, which started in May 1992 and ended in December 1992, involved 97 patients with advanced epithelial ovarian cancer. The target study population had disease relapse or disease progression within 12 months of the last administration of a first-line or second-line platinum-based regimen with at least one bidimensionally measurable target lesion. The patients received docetaxel at a dose of 100 mg/m2 given as a 1-hour infusion every 3 weeks without premedication for minimizing potential hypersensitivity. Docetaxel-induced side effects were graded according to the National Cancer Institute's Common Toxicity Criteria.
Results: The overall response rate was 23.6% in 76 assessable patients versus 20% if all 90 eligible patients were included in the comparison (95% confidence interval [CI] = 11%-29%). Among 34 eligible patients whose tumor progressed on the most recent platinum treatment, the response rate was 23.5% (95% CI = 8%-39%). The median progression-free survival for all eligible patients was 3.9 months, and the median overall survival was 8.4 months. Docetaxel-associated toxicity in 90 assessable patients consisted of short-lived neutropenia in 81 (90%) patients, which was complicated by fever and hospitalization in seven (8%); hypersensitivity reactions were seen in 29 (31%) patients, with significant reactions seen in seven (8%); and neurotoxicity in 43 (48%) patients, with grade 3 or above toxicity seen in only three (3%). The treatment also produced skin reactions in 58 (64%) patients, of whom only four (4%) showed the intensity of grade 3. Eleven (12%) patients experienced pleural effusions, which were the effects of the drug considered to be of greatest concern. Peripheral edema and weight gain due to fluid retention were reported in 40 (44%) and 17 (19%) patients, respectively.
Conclusion: Docetaxel appears to be effective in the treatment of platinum-refractory ovarian cancer patients.