Phase I trial of N-(Phosphonacetyl)-L-aspartic acid (PALA).

N-(Phosphonacetyl)-L-aspartic acid (PALA) was given as a 5-day continuous infusion in a phase I trial. Dose-limiting toxic effects noted were diarrhea occurring at doses of greater than or equal to 6 g/m2/course, mucositis occurring at doses of greater than or equal to 7.5 g/m2/course, and skin rash occurring at doses greater than 9 g/m2/course. No significant CNS, hemorrhagic, gastrointestinal, or hematologic toxicity was noted. In patients with measurable tumor volume, no significant antitumor responses were seen. A dose of 9 g/m2/course is recommended for a phase II trial.