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.

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.

Phase I trial of high-dose tamoxifen in combination with cisplatin in patients with lung cancer and other advanced malignancies.

BACKGROUND: Tamoxifen has been reported to enhance the antitumor activity of cisplatin in preclinical models by modulation of protein kinase C signal transduction and apoptosis-related pathways. METHODS: We conducted a phase I study of high-dose oral tamoxifen in combination with intravenous cisplatin, with two objectives: 1) to determine tolerability, and 2) to determine the daily tamoxifen dose required to achieve serum levels equivalent to in vitro concentrations reported to enhance cisplatin cytotoxicity in preclinical models. Tamoxifen was administered days one through seven at escalating daily doses of 160 mg/m2 (n = 5), 200 mg/m2 (n = 6), and 250 mg/m2 (n = 4) by patient cohort, followed by cisplatin at 100 mg/m2 on day eight. Serum concentrations of tamoxifen and its hydroxylated metabolite N-desmethyltamoxifen were determined by high-performance liquid chromatography (HPLC) on day eight of the first treatment cycle in seven patients. RESULTS: Fifteen patients with advanced malignancies received treatment with tamoxifen at 160 mg/m2, 200 mg/m2, and 250 mg/m2 per cycle, respectively. Serum concentrations of tamoxifen and N-desmethyltamoxifen on day eight of the first cycle ranged from 1.75-8.22 microM (mean 4.72 microM) and 3.62-10.85 microM (mean 3.87 microM), respectively. Toxicity analysis demonstrated that grade 3/4 nonhematological toxicity occurred in 0/5 at a tamoxifen dose of 160 mg/m2, 1/6 at a tamoxifen dose of 200 mg/m2, and in 1/4 patients at the 250 mg/m2 dose level. No grade 4 hematological toxicity occurred. Classic dose-limiting toxicity was not observed; the trial was closed to further accrual after documentation that targeted tamoxifen levels (around 5 microM) were achieved with daily tamoxifen doses > or = 160 mg/m2 in combination with cisplatin. CONCLUSIONS: This regimen of high-dose tamoxifen in combination with cisplatin can be safely administered. Serum tamoxifen levels comparable to concentrations required for enhancement of cisplatin sensitivity in vitro are clinically achievable with acceptable toxicity. The level of antitumor activity in nonsmall cell lung cancer NSCLC is encouraging (partial response in 4/10 patients). Based on these data, a Phase II study of high-dose tamoxifen in combination with cisplatin in patients with metastatic NSCLC is being conducted through the Southwest Oncology Group.