Platinum-free combination chemotherapy in patients with advanced or metastatic transitional cell carcinoma.

BACKGROUND: Platinum-based regimens have improved response rates and survival in patients with advanced transitional cell carcinoma (TCC) of the urothelial tract. However, the toxicities of platinum-based chemotherapy are considerable. Regimens with reduced toxicity that are applicable to a broader group of TCC patients without sacrificing activity therefore are of interest. METHODS: Because gemcitabine, paclitaxel, and methotrexate have each been reported to possess single-agent activity in this disease, the authors evaluated the tolerability and efficacy of fixed doses of paclitaxel (100 mg/m(2) over 3 hours) and methotrexate (30 mg/m(2)) with escalating doses of gemcitabine (800-1000 mg/m(2)), all given on Days 1 and 8 every 21 days, in patients with previously untreated unresectable or metastatic TCC. RESULTS: Twenty-five patients were enrolled. Two patients were ineligible and were excluded from analysis. Because no dose-limiting toxicity occurred in the first 4 patients who were given gemcitabine at a dose of 800 mg/m(2), the gemcitabine dose was escalated to 1000 mg/m(2) in the next 21 patients. Of the 21 patients assessable for response, 6 had achieved a complete response (CR) and 6 had achieved a partial response, for an overall response rate of 57%. An additional patient was converted to a CR surgically. The median overall and progression-free survival times were 18 months and 9.2 months, respectively. Toxicity was predominantly neutropenia: Grade 3 in 9 patients (39%) and Grade 4 in 4 patients (17%) (according to the Southwest Oncology Group Toxicity Criteria, version 12/1994). One patient died of septic shock associated with febrile neutropenia after three cycles. CONCLUSIONS: The regimen of gemcitabine, paclitaxel, and methotrexate at this dose and schedule was found to possess activity in patients with locally advanced or metastatic TCC. Further studies of this regimen are warranted.

Population-based maximum tolerated dose of irinotecan and carboplatin.

A novel schema of intrapatient dose escalation was applied to determine a population-based maximum tolerated dose (pMTD) for irinotecan (CPT-11, Camptosar) and carboplatin (Paraplatin) in a phase I trial. A total of 74 patients with advanced solid tumors were enrolled with the following characteristics: men/women, 46/28; median age, 61 years; 51 patients with and 23 patients without prior chemotherapy; performance status of 0-1 (93%) and 2 (7%). Patients were started at dose level 1 with irinotecan at 200 mg/m2, and carboplatin at an area under the concentration-time curve (AUC) of 5 mg/mL x min, administered every 21 days. Depending on degree of toxicity observed, the dose for each patient in each subsequent cycle was determined according to a predetermined schema of dose levels. Individual maximum tolerated dose (iMTD) was determined for each patient. The pMTD was defined as the highest dose level for which the incidence of dose-limiting toxicity occurred in less than 33% of the patient population. The most common dose-limiting toxicity included neutropenia (58%), thrombocytopenia (15%), diarrhea (8%), and nausea/emesis (7%). The iMTD ranged from dose level-3 (irinotecan at 100 mg/m2 and carboplatin at an AUC of 4) to dose level 5 (irinotecan at 350 mg/m2 and carboplatin at AUC 6). The pMTD was determined to be dose level-1 and 1 for previously chemotherapy-treated and--untreated patients, respectively. Fifty-nine patients were assessable for response. Of note, a response rate of 40% was observed in 15 patients with relapsed small-cell lung cancer previously treated with platinum-based therapy. We recommend dose level 1 of irinotecan (200 mg/m2) and carboplatin (AUC 5) for chemotherapynaive patients, and dose level-1 of irinotecan (150 mg/m2) and carboplatin (AUC 5) for chemotherapy-treated patients in phase II trials.

Phase I trial of gemcitabine and paclitaxel in advanced solid tumors.

PURPOSE: Gemcitabine and paclitaxel are chemotherapeutic agents with clinical antitumor activity in a broad range of malignant solid tumors. Because of preclinical synergy, unique mechanisms of action and resistance, and nonoverlapping toxicities, gemcitabine and paclitaxel combinations are attractive for testing in clinical trials. Prior weekly gemcitabine and paclitaxel regimens administered on a 28-day cycle have been limited by cumulative hematological toxicity on day 15, thus reducing the planned gemcitabine dose intensity. We therefore conducted a phase I trial of a 21-day schedule of weekly gemcitabine and paclitaxel to determine the tolerability, maximum tolerated dose (MTD), and preliminary estimates of efficacy of this regimen. PATIENTS AND METHODS: Forty-one patients with advanced malignant solid tumors were accrued. Gemcitabine was given at a fixed dose of 1000 mg/m2 while paclitaxel was administered at an initial dose of 60 mg/m2, then escalated by 15 mg/m2 increments over seven dose levels to a prospectively planned maximum dose of 150 mg/m2. Both agents were infused intravenously on days one and eight every 21 days. At least three patients were enrolled per dose level. No intrapatient dose escalation was allowed. RESULTS: All patients were assessable for toxicity and 31 were assessable for response. The regimen was generally well-tolerated. Dose-limiting thrombocytopenia was observed in one patient at a paclitaxel dose of 135 mg/m2/week (dose level 6). After expansion of this dose level by 14 additional patients, no further dose-limiting toxicities were observed although one patient at dose level seven died of neutropenic sepsis after completing three cycles. There were eight partial responders for an overall response proportion of 26% (95% CI: 11, 41). Twelve patients (39%) had stable disease. CONCLUSION: This 21-day schedule of gemcitabine and paclitaxel is safe, well-tolerated, and active. The recommended phase II dose is gemcitabine 1000 mg/m2 and paclitaxel 150 mg/m2 on days one and eight every 21 days. The antitumor activity observed with this regimen warrants further investigation.