Abstract | PURPOSE: To test whether nelarabine is an effective agent for indolent leukemias and to evaluate whether there is a relationship between cellular pharmacokinetics of the analog triphosphate and clinical responses. PATIENTS AND METHODS: RESULTS: Responses were achieved in 20%, 15%, and 63% of patients receiving schedule A, B, and C, respectively. Histologic category, number of prior therapies, and fludarabine refractoriness did not influence the response rate. The most common nonhematologic toxicity was peripheral neuropathy. Grade 4 neutropenia and thrombocytopenia complicated 23% and 26% of courses respectively, and were significantly more frequent among patients with pre-existing marrow failure. Pharmacokinetics of plasma nelarabine and arabinosylguanine ( ara-G) and of cellular ara-G triphosphate ( ara-GTP) were similar in the two groups of diagnoses, and the elimination of ara-GTP from leukemia cells was slow (median, > 24 hours). The median peak intracellular concentrations of ara-GTP were significantly different (P = .0003) between responders (440 micromol/L; range, 35 to 1,438 micromol/L; n = 10) and nonresponders (50 micromol/L; range, 22 to 178 micromol/L; n = 15). CONCLUSION:
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Authors | Varsha Gandhi, Constantine Tam, Susan O'Brien, Roxanne C Jewell, Carlos O Rodriguez Jr, Susan Lerner, William Plunkett, Michael J Keating |
Journal | Journal of clinical oncology : official journal of the American Society of Clinical Oncology
(J Clin Oncol)
Vol. 26
Issue 7
Pg. 1098-105
(Mar 01 2008)
ISSN: 1527-7755 [Electronic] United States |
PMID | 18309944
(Publication Type: Clinical Trial, Phase I, Journal Article, Research Support, N.I.H., Extramural)
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Chemical References |
- Antineoplastic Agents
- Arabinonucleosides
- Arabinonucleotides
- nelarabine
- 9-beta-D-arabinofuranosylguanosine 5'-triphosphate
- Guanosine Triphosphate
- DNA (Cytosine-5-)-Methyltransferases
- Vidarabine
- fludarabine
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Topics |
- Adult
- Aged
- Aged, 80 and over
- Antineoplastic Agents
(pharmacokinetics, therapeutic use)
- Arabinonucleosides
(pharmacokinetics, therapeutic use)
- Arabinonucleotides
(metabolism)
- DNA (Cytosine-5-)-Methyltransferases
(antagonists & inhibitors)
- Drug Therapy, Combination
- Female
- Guanosine Triphosphate
(analogs & derivatives, metabolism)
- Humans
- Leukemia, Lymphocytic, Chronic, B-Cell
(blood, drug therapy)
- Leukemia, Prolymphocytic, T-Cell
(blood, drug therapy)
- Male
- Middle Aged
- Tumor Cells, Cultured
- Vidarabine
(analogs & derivatives, pharmacokinetics, therapeutic use)
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