Kimberly Binger

Phase I trial of weekly paclitaxel and BMS-214662 in patients with advanced solid tumors.

Purpose: To assess the maximum tolerated dose (MTD), dose-limiting toxicity (DLT), pharmacodynamics, and antitumor activity of continuous weekly-administered paclitaxel and BMS-214662, a novel farnesyl transferase inhibitor. Experimental Design: Patients were treated every week as tolerated with i.v. paclitaxel (fixed dose, 80 mg/m2/wk) administered over 1 h followed by i.v. BMS-214662 (escalating doses, 80–245 mg/m2/wk) over 1 h starting 30 min after completion of paclitaxel. Results: Twenty-six patients received 94 courses (one course, 21 days) of study treatment. Two patients received five courses of BMS-214662 as a weekly 24-h infusion (209 mg/m2/wk). The most common toxicities were grade 1 to 2 nausea/vomiting and/or diarrhea. DLTs observed at or near the MTD (200 mg/m2/wk) were grade 4 febrile neutropenia with sepsis occurring on day 2 of course 1 (245 mg/m2/wk), reversible grade 3 to 4 serum transaminase increases on day 2, and grade 3 diarrhea (200 and 245 mg/m2/wk). Objective partial responses were observed in patients with pretreated head and neck, ovarian, and hormone-refractory prostate carcinomas, and leiomyosarcoma. The observed pharmacokinetics of paclitaxel and BMS-214662 imply no interaction between the two. Significant inhibition (>80%) of farnesyl transferase activity in peripheral mononuclear cells was observed at the end of BMS-214662 infusion. Conclusions: Pretreated patients with advanced malignancies can tolerate weekly paclitaxel and BMS-214662 at doses that achieve objective clinical benefit. Due to multiple DLTs occurring at the expanded MTD, the recommended phase 2 dose and schedule is paclitaxel (80 mg/m2 over 1 h) and BMS-214662 (160 mg/m2 over 1 h) administered weekly.

Gemcitabine, Paclitaxel, and piritrexim: a phase I study.

Piritrexim is a new antifolate that has shown activity in methotrexate-resistant tumors. Gemcitabine is an antimetabolite similar in structure to cytosine arabinoside with early studies demonstrating activity in a variety of cancers. It also has apparent synergistic activity with antifolates from initial work in tumor models. Paclitaxel is an antimicrotubule agent that has a wide spectrum of activity against a variety of solid tumors. The combination of gemcitabine, paclitaxel, and piritrexim was assessed in this phase I trial. Thirty patients were enrolled. The starting doses were piritrexim 25 mg orally twice daily (days 1–4, 15–18), paclitaxel 75 mg/m2 (days 1, 15), and gemcitabine 750 mg/m2 (days 1, 15), which then was escalated in a stepwise fashion. Four patients achieved stable disease while on study, whereas one patient with a poorly differentiated neuroendocrine tumor achieved a partial response. The main toxicity was myelosuppression. The maximum tolerated dose was thought to be piritrexim 25 mg orally three times daily (days 1–4), paclitaxel 150 to 175 mg/m2 (days 1, 15), and gemcitabine 1,000 mg/m2 (days 1, 15). The combination of these new antifolates with paclitaxel and gemcitabine appears safe and should be considered for phase II trials in known responsive tumors such as transitional cell carcinomas.