Drug Interactions

Nelarabine and ara-G did not significantly inhibit the activities of the human hepatic cytochrome P450 isoenzymes 1A2, 2A6, 2B6, 2C8, 2C9, 2C19, 2D6, or 3A4 in vitro at concentrations of nelarabine and ara-G up to 100 μM.

There is in vitro evidence that pentostatin is a strong inhibitor of adenosine deaminase. This may result in a reduction in the conversion of the pro-drug nelarabine to its active moiety and consequently in a reduction in efficacy of nelarabine and/or change in adverse event profile of either drug. Administration of nelarabine in combination with adenosine deaminase inhibitors, such as pentostatin, is not recommended. 

Carcinogenesis, Mutagenesis, Impairment of Fertility

Carcinogenicity testing of nelarabine has not been done. However, nelarabine was mutagenic when tested in vitro in L5178Y/TK mouse lymphoma cells with and without metabolic activation. No studies have been conducted in animals to assess genotoxic potential or effects on fertility. The effect on human fertility is unknown. 

Pregnancy

Pregnancy Category D. (See WARNINGS.) 

Nursing Mothers

It is not known whether nelarabine or ara-G are excreted in human milk. Because many drugs are excreted in human milk and because of the potential for serious adverse reactions in nursing infants from ARRANON, nursing should be discontinued in women who are receiving therapy with ARRANON. 

Pediatric Use

(See CLINICAL STUDIES, Pediatric Clinical Study). 

Geriatric Use

Clinical studies of ARRANON did not include sufficient numbers of patients aged 65 and over to determine whether they respond differently from younger patients. In an exploratory analysis, increasing age, especially age 65 years and older, appeared to be associated with increased rates of neurologic adverse events. 

Use in Renally Impaired Patients

Ara-G clearance decreased as renal function decreased (see CLINICAL PHARMACOLOGY). Because the risk of adverse reactions to this drug may be greater in patients with severe renal impairment (CLcr<30 mL/min), these patients should be closely monitored for toxicities when treated with ARRANON (see DOSAGE AND ADMINISTRATION). 

Use in Hepatically Impaired Patients

The influence of hepatic impairment on the pharmacokinetics of nelarabine has not been eva luated. Because the risk of adverse reactions to this drug may be greater in patients with severe hepatic impairment (bilirubin >3.0 mg/dL), these patients should be closely monitored for toxicities when treated with ARRANON. 

ADVERSE REACTIONS

ARRANON was studied in 459 patients in Phase I and Phase II clinical trials. The safety profile for the recommended dosages of ARRANON is based on data from 103 adult patients enrolled and treated in the CALGB 19801 and an adult chronic lymphocytic leukemia study (PGAA2003) who were treated with the recommended dose and schedule. The safety profile for children is based on data from 84 pediatric patients enrolled and treated in the COG P9673 study who were treated with the recommended dose and schedule.

The most common adverse events in pediatric patients, regardless of causality, were hematologic disorders (anemia, leukopenia, neutropenia, and thrombocytopenia). Of the non-hematologic adverse e