A dose-escalation study of pemetrexed and docetaxel in non-small-cell lung cancer

A phase I study was conducted to determine the maximum tolerated doses (MTD) and the dose-limiting toxicities (DLT) of pemetrexed and docetaxel in patients with advanced unresectable or metastatic non-small-cell lung cancer (NSCLC). Patients were treated with escalating doses of pemetrexed (400-600 mg/m(2) as a 10-min intravenous infusion) and docetaxel (65-85 mg/m(2) as a 1-h intravenous infusion) on day 1, every 3 weeks. An expanded accrual at the level of the recommended dose (RD) had been scheduled. Forty-two patients with metastatic NSCLC were enrolled in the phase I study and 20 additional patients at the RD level. The MTD could not be reached even at the doses of 550 and 85 mg/m(2) for pemetrexed and docetaxel, respectively, which are higher than the recommended dose for each drug given as a single agent. Therefore, the RD was defined at 500 mg/m(2) pemetrexed and 75 mg/m(2) docetaxel. Among the 164 administered chemotherapy cycles (phase I part), there were three episodes of febrile neutropenia whereas 13 (7.9%) and 11 (6.7%) cycles were complicated with grade III and IV neutropenia, respectively. Three patients developed grade III/IV thrombocytopenia. Non-hematologic toxicity was mild with grade III fatigue occurring in three (6.7%) patients. There was no toxic death. The favorable toxicity profile of the regimen was confirmed in patients treated at the RD level. Overall, one complete (CR) and 13 partial responses (PR) (overall response rate = 23; 95% C.I:12.4-33.5%] were documented. The combination of pemetrexed and docetaxel seems to be an effective regimen in NSCLC with acceptable and manageable toxicity, which merits further investigation.

A Phase 1 Study of Pralatrexate in Combination with Paclitaxel or Docetaxel in Patients with Advanced Solid Tumors

PURPOSE

Pralatrexate is a rationally designed antifolate with greater preclinical antitumor activity than methotrexate. Pralatrexate was synergistic with paclitaxel and with docetaxel in mouse xenograft experiments. This phase 1 study was designed to determine the maximum tolerated dose and toxicity of pralatrexate plus paclitaxel or docetaxel in patients with advanced cancer.

EXPERIMENTAL DESIGN

Pralatrexate was administered i.v. every 2 weeks (days 1 and 15) in a 4-week cycle. Depending on the taxane used and dose being tested, the taxane was administered on days 1 and 15; days 2 and 16; or days 1, 8, and 15. In the latter part of the study, patients in the docetaxel arm were treated with vitamin B(12) and folic acid supplementation to mitigate toxicity and allow pralatrexate dose escalation.

RESULTS

For the combination of pralatrexate plus paclitaxel without vitamin supplementation, dose-limiting stomatitis and peripheral neuropathy were encountered at the lowest dose levels tested. For pralatrexate plus docetaxel plus vitamin supplementation, pralatrexate 120 mg/m(2) plus docetaxel 35 mg/m(2) administered on the same day every other week was defined as the maximum tolerated dose and schedule, with dose-limiting toxicities at higher dose combinations including stomatitis and asthenia. Significant antitumor activity was observed for this combination in patients with non-small-cell lung cancer.

CONCLUSIONS

Pralatrexate (120 mg/m(2)) plus docetaxel (35 mg/m(2)) plus vitamin supplementation is well tolerated with signs of efficacy against non-small-cell lung cancer that merit phase 2 testing.