TY - JOUR
T1 - Phase I clinical and pharmacogenetic study of weekly TAS-103 in patients with advanced cancer
AU - Ewesuedo, R. B.
AU - Iyer, L.
AU - Das, S.
AU - Koenig, A.
AU - Mani, S.
AU - Vogelzang, N. J.
AU - Schilsky, R. L.
AU - Brenckman, W.
AU - Ratain, M. J.
PY - 2001/4/1
Y1 - 2001/4/1
N2 - Purpose: TAS-103 is an inhibitor of both topoisomerase I and II enzymes with broad antitumor activity. It is metabolized to TAS-103-glucuronide (TAS-103-G) predominantly by uridine diphosphate glucuronosyltransferase isoform 1A1 (UGT1A1). We conducted a phase I study to determine the maximum-tolerated dose (MTD) and dose-limiting toxicity (DLT) of TAS-103 when administered on a weekly schedule to patients with advanced cancer. In addition, we evaluated the influence of UGT1A1 genotype on the pharmacokinetics and toxicity of TAS-103. Patients and Methods: Thirty-two patients were treated with escalating doses (50 to 200 mg/m2) of TAS-103, administered intravenously over 1 hour each week for 3 weeks. Pharmacokinetic analysis was performed at the 130-, 160-, and 200-mg/m2 dose levels. UGT1A1 genotypes were determined using reverse-transcription polymerase chain reaction techniques. Results: DLT (grade 3 neutropenia) was observed in 5 of 12 patients at 160 mg/m2 and in 3 of 6 patients at 200 mg/m2. At 160 mg/m2, there was a significant correlation between areas under the curve (AUCs) for TAS-103 and TAS-103-G (r = 0.76, P < .05) and an apparent relationship between TAS-103 AUC and D 15 absolute neutrophil count (r = -0.63, P < .05, n = 11, one outlier excluded). UGT1A1 genotype did not influence clearance of TAS-103. Conclusion: We recommend a dose of 130 to 160 mg/m2, or 250 to 300 mg administered using the above weekly schedule for phase II studies. Further studies to characterize the pharmacodynamics and pharmacogenetics of TAS-103 are warranted.
AB - Purpose: TAS-103 is an inhibitor of both topoisomerase I and II enzymes with broad antitumor activity. It is metabolized to TAS-103-glucuronide (TAS-103-G) predominantly by uridine diphosphate glucuronosyltransferase isoform 1A1 (UGT1A1). We conducted a phase I study to determine the maximum-tolerated dose (MTD) and dose-limiting toxicity (DLT) of TAS-103 when administered on a weekly schedule to patients with advanced cancer. In addition, we evaluated the influence of UGT1A1 genotype on the pharmacokinetics and toxicity of TAS-103. Patients and Methods: Thirty-two patients were treated with escalating doses (50 to 200 mg/m2) of TAS-103, administered intravenously over 1 hour each week for 3 weeks. Pharmacokinetic analysis was performed at the 130-, 160-, and 200-mg/m2 dose levels. UGT1A1 genotypes were determined using reverse-transcription polymerase chain reaction techniques. Results: DLT (grade 3 neutropenia) was observed in 5 of 12 patients at 160 mg/m2 and in 3 of 6 patients at 200 mg/m2. At 160 mg/m2, there was a significant correlation between areas under the curve (AUCs) for TAS-103 and TAS-103-G (r = 0.76, P < .05) and an apparent relationship between TAS-103 AUC and D 15 absolute neutrophil count (r = -0.63, P < .05, n = 11, one outlier excluded). UGT1A1 genotype did not influence clearance of TAS-103. Conclusion: We recommend a dose of 130 to 160 mg/m2, or 250 to 300 mg administered using the above weekly schedule for phase II studies. Further studies to characterize the pharmacodynamics and pharmacogenetics of TAS-103 are warranted.
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U2 - 10.1200/JCO.2001.19.7.2084
DO - 10.1200/JCO.2001.19.7.2084
M3 - Article
C2 - 11283142
AN - SCOPUS:0035300677
SN - 0732-183X
VL - 19
SP - 2084
EP - 2090
JO - Journal of Clinical Oncology
JF - Journal of Clinical Oncology
IS - 7
ER -