Phase I trial of extracellular adenosine 5'-triphosphate in patients with advanced cancer.
Adenosine 5'-triphosphate (ATP) has antineoplastic activity in vitro and in murine tumor systems, but there are no data in humans defining its potential use as an antineoplastic agent. We conducted a phase I study to determine the spectrum of toxicity, maximum safely tolerated dose (MTD), and pharmacokinetics of intravenous ATP. Fourteen men with advanced cancer received 96-hour infusions of ATP once monthly in doses ranging from 50 to 100 micrograms/kg/minute. Toxicity was assessed by standard National Cancer Institute (NCI) criteria, cardiac function was monitored serially by two-dimensional echocardiography, and whole blood ATP was measured serially in a subset of patients. ATP was generally well tolerated and no significant hematologic toxicity was noted. The dose-limiting toxicity was a cardiopulmonary reaction characterized by chest tightness and dyspnea that resolved within seconds of discontinuing ATP. Dose-limiting cardiopulmonary toxicity occurred in 3 of 3 patients at 100 micrograms/kg/minute, in 3 of 6 patients at 75 micrograms/kg/minute, and 4 of 11 patients at 50 micrograms/kg/minute. Whole blood ATP levels significantly increased with treatment, reaching a steady state by 24 hours and returning to or near baseline by 1 week after treatment. Plateau levels were 63%, 67%, and 116% above base-line at 50, 75, and 100 micrograms/kg/min, respectively. We conclude that prolonged infusions of ATP are feasible with acceptable toxicity and that 50 micrograms/kg/minute is both the MTD and the most appropriate dose rate for subsequent Phase II testing of 96-hour infusions of ATP in patients with advanced cancer.
Haskell
C M
CM
Wadsworth Cancer Center, West Los Angeles VA Medical Center, CA 90073, USA.
Wong
M
M
Williams
A
A
Lee
L Y
LY
D000255:Adenosine Triphosphate / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D000368:Aged; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000188:drug therapy* / Q000473:pathology; D015656:Respiratory Mechanics / Q000187:drug effects; D013318:Stroke Volume / Q000187:drug effects
D000970:Antineoplastic Agents; D000255:Adenosine Triphosphate