Seven-week continuous-infusion paclitaxel plus concurrent radiation therapy for locally advanced non-small cell lung cancer: a phase I study.

The goal of this National Cancer Institute-sponsored phase I trial is to determine the feasibility, toxicity, and pharmacokinetics of continuous-infusion (24 hr/d, 7 d/wk, 7 weeks total) intravenous paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) when combined with standard, curative-intent radiation therapy (RT) for previously untreated, locally advanced non-small cell lung cancers. Eligible patients have locally advanced (T4NXM0 or TXN2-3M0) non-small cell cancer ineligible for potentially curative surgical resection, a good performance status, adequate hematologic, hepatic, and renal functions, and no distant metastases. All patients receive a total tumor dose of 64.8 Gy megavoltage RT in 7 weeks at 1.8 Gy once daily, 5 d/wk. Paclitaxel is delivered by continuous intravenous infusion starting 48 hours before RT and continuing for its duration. The dose of paclitaxel is escalated in cohorts of three patients in a standard phase I design. To date, 16 patients have entered the trial, and 15 are evaluable for toxicity in this ongoing study. Paclitaxel dose is currently at a 6.5 mg/m2/d dose level, with no dose-limiting toxicity recorded thus far. One patient at the highest dose level has had grade 2 pneumonitis. With the exception of anemia, toxicities are those that would be expected from RT alone. A slowly progressive normocytic anemia with no renal dysfunction was found to be associated with an acquired hypoerythropoietin state. These findings indicate that this therapy is feasible and well tolerated through current dose levels, with no dose-limiting toxicity. Dose escalation is ongoing.

Intensive radiation therapy concurrent with up to 7-week continuous-infusion paclitaxel for locally advanced solid tumors: phase I studies.

Patients with locally advanced solid tumors of the lung, head and neck, and malignant astrocytomas usually succumb to their disease despite aggressive standard therapy. Laboratory data suggest that the addition of 1.0 to 10 nmol/L paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ), a microtubule stabilizing drug, to radiation therapy may result in significant radiation sensitization, perhaps due to accumulation of cells at G2/M. Relatively low concentrations (1.0 to 10 nmol/L) appear to be optimal for direct cytotoxicity and radiosensitization in vitro. Within this dose range, more prolonged exposure seems to result in higher response rates. The phase I trials reported here are designed to test the combination of paclitaxel, administered by continuous intravenous infusion (24 hours a day, 7 days a week), and standard, curative-intent radiation therapy. The ultimate goal of this study is to improve local and systemic control and survival for patients with these three tumor types. To date, 39 evaluable patients are enrolled in this study; there has been no dose-limiting toxicity up to 6.5 mg/m2/d. Observed toxicities include anemia, lymphopenia, mucositis, and cutaneous toxicities.

Seven-week continuous-infusion paclitaxel with concurrent radiotherapy for locally advanced head and neck squamous cell cancer: a phase I study.

The goal of this National Cancer Institute-sponsored phase I trial is to determine the feasibility, toxicity, and pharmacokinetics of continuous-infusion (24 hr/d, 7 d/wk, 7-week total) intravenous paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) combined with standard curative radiotherapy (RT) for previously untreated, locally advanced head and neck squamous cell cancers. Eligible patients have squamous cell cancers of the head and neck with expected 5-year survival rates of < or =25%; a good performance status; adequate hematologic, hepatic, and renal functions; and no distant metastases. All patients receive 70 Gy megavoltage RT in 7 weeks (2 Gy/d x 5 d/wk). Paclitaxel is delivered by protracted venous infusion starting 48 hours before RT and continuing for its duration. Biopsies for cell-cycle distribution analyses and paclitaxel tissue levels are obtained, if possible, before beginning paclitaxel and after 48 hours just before RT begins. The dose of paclitaxel is escalated in cohorts of three patients. Eighteen patients are evaluable for toxicity. Treatment has been completed through the 6.5 mg/m2/d dose level and is ongoing at 10.5 mg/m2/d. There has been no dose-limiting toxicity thus far. With the exception of anemia, toxicity is commensurate with what would be expected from RT alone. A slowly progressive normocytic anemia with no renal dysfunction was found to be associated with an acquired hypoerythropoietin state. Tumor biopsies have suggested the possibility of paclitaxel-induced mitotic arrest. This therapy is feasible and has been well tolerated through current dose levels with no dose-limiting toxicity. There is a suggestion of biologic activity evidenced by the anemia and the possibility of alteration in cell-cycle distributions. Dose escalation is ongoing.