Activity and Toxicity of Intravenous Erwinia Asparaginase Following Allergy to E. coli-Derived Asparaginase in Children and Adolescents With Acute Lymphoblastic Leukemia.

BACKGROUND: Erwinia asparaginase is antigenically distinct from E.coli-derived asparaginase and may be used after E.coli-derived asparaginase hypersensitivity. In a single-arm, multicenter study, we evaluated nadir serum asparaginase activity (NSAA) and toxicity with intravenously administered asparaginase Erwinia chrysanthemi (IV-Erwinia) in children and adolescents with acute lymphoblastic leukemia (ALL) or lymphoblastic lymphoma with hypersensitivity to E.coli-derived asparaginase. PATIENTS AND METHODS: Between 2012 and 2013, 30 patients (age 1-17 years) enrolled from 10 centers. Patients received IV-Erwinia, 25,000 IU/m(2)/dose on Monday/Wednesday/Friday, for 2 consecutive-weeks (6 doses = 1 cycle) for each dose of pegaspargase remaining in the original treatment plan. The primary objective was to determine the proportion of patients achieving NSAA ≥ 0.1 IU/ml 48 hr after dose 5 in Cycle 1. Secondary objectives included determining the proportion achieving NSAA ≥ 0.1 IU/ml 72 hr after Cycle 1 dose 6, and the frequency of asparaginase-related toxicities. RESULTS: Twenty-six patients completed Cycle 1; 24 were evaluable for NSAA assessment. In Cycle 1, NSAA ≥ 0.10 IU/ml was detected in 83% of patients (95% confidence interval [CI], 63-95%) 48 hr post-dose 5 (mean ± SD; 0.32 IU/ml ± 0.23), and in 43% (95% CI, 22-66%) 72 hr post-dose 6 (mean ± SD; 0.089 IU/ml ± 0.072). For all 30 patients over all cycles, hypersensitivity/infusional reactions with IV-Erwinia occurred in 37%, pancreatitis 7%, and thrombosis 3%. CONCLUSIONS: IV-Erwinia administration in children/adolescents appeared feasible and tolerable. A therapeutically-effective NSAA (≥ 0.10 IU/ml) was achieved in most patients at 48 hr, but in fewer than half 72 hr post-dosing, suggesting that monitoring NSAA levels and/or every 48 hr dosing may be indicated.

Safety profile of asparaginase Erwinia chrysanthemi in a large compassionate-use trial.

BACKGROUND: L-Asparaginase is an integral component of standard chemotherapy regimens for the treatment of acute lymphoblastic leukemia (ALL). Clinical hypersensitivity, a common reason for treatment discontinuation, has been reported in 10-30% of patients receiving Escherichia coli-derived asparaginase. After hypersensitivity, E. coli-derived asparaginase should be discontinued and an alternative asparaginase preparation, such as asparaginase Erwinia chrysanthemi, may be initiated. We conducted a compassionate-use study to collect additional safety information on asparaginase Erwinia chrysanthemi and to support FDA approval of the product. PROCEDURE: Patients with ALL or lymphoblastic lymphoma (LBL; N = 1368) who developed a hypersensitivity reaction (grade ≥2) to an E. coli-derived asparaginase participated in this trial. The recommended asparaginase Erwinia chrysanthemi dose was 25,000 IU/m(2) three days per week (Monday/Wednesday/Friday) for two consecutive weeks for each missed pegylated E. coli-derived asparaginase dose and 25,000 IU/m(2) for each missed nonpegylated asparaginase dose for the completion of their planned asparaginase treatment. RESULTS: Adverse event reports and/or case report forms were completed for 940 patients. The most common adverse event (AE) was hypersensitivity (13.6%). Eighteen patients (1.9%) died during the study. Most patients (77.6%) completed their planned asparaginase treatment with asparaginase Erwinia chrysanthemi. There was no apparent difference in the incidence of the most commonly reported AEs with asparaginase treatment by age, administration, or disease state. CONCLUSIONS: This study further established the safety profile of asparaginase Erwinia chrysanthemi in patients with ALL or LBL who had a hypersensitivity reaction to an E. coli-derived asparaginase.

The evolution of legislation to regulate pediatric clinical trials: Present and continuing challenges.

Children suffer from many of the same diseases as adults and are often treated with the same agents. However, it was not until 1997 that legislation mandating studies in children was introduced in the United States. A 2000 International Conference on Harmonisation (ICH) Guidance on the Clinical Investigation of Medicinal Products in the Pediatric Population intended to encourage and facilitate timely pediatric clinical trials detailed critical issues in pediatric drug development and ways to ethically study the safety and efficacy of drugs in the unique and vulnerable pediatric population. In 2005, there is draft legislation in Europe. In Japan, pediatric data are not currently required although studies in pediatric populations are encouraged. This chapter describes the history of legislation on the study of drugs in the pediatric population and details present and continuing challenges for the child, parent/guardian, manufacturer and health authority.

Safety and efficacy of anastrozole for the treatment of pubertal gynecomastia: a randomized, double-blind, placebo-controlled trial.

Pubertal gynecomastia is thought to result from transient imbalances between estrogen and androgen concentrations. Anastrozole (ARIMIDEX), a potent and selective aromatase inhibitor, decreases estrogen and increases testosterone concentrations in pubertal boys. The safety and efficacy of anastrozole for the treatment of pubertal gynecomastia were evaluated. In a randomized, double-blind, placebo-controlled study of 80 boys, aged 11-18 yr, with pubertal gynecomastia that had not reduced over a 3-month interval, subjects received either anastrozole (1 mg) or placebo once daily for 6 months. A response was defined as a 50% or greater reduction in the calculated volume of both breasts combined using ultrasonography measurements. A comparison of response rates was performed using logistic regression analysis. Secondary end points included changes in serum hormone concentrations. The percentage of patients with a response was 38.5% for the anastrozole group and 31.4% for the placebo group (odds ratio, 1.513; 95% confidence interval, 0.496-4.844; P = 0.47). At 6 months, the median percent change in the testosterone/estradiol ratio was 166% for the anastrozole group and 39% for the placebo group. Anastrozole treatment was well tolerated. In patients with pubertal gynecomastia, no significant difference in the percentage of patients with a 50% or greater reduction in total breast volume, as calculated from ultrasonography measurements, was demonstrated between the anastrozole and placebo groups.

Development of asparaginase Erwinia chrysanthemi for the treatment of acute lymphoblastic leukemia.

Since it was identified in 1963 as the antileukemic agent in guinea pig serum, L-asparaginase (ASNase) has become an integral component of chemotherapy protocols to treat patients with acute lymphoblastic leukemia (ALL). Escherichia coli and Erwinia chrysanthemi provide the sources of ASNase used clinically today. From the time ASNase was first introduced into treatment protocols, the 5-year survival rate has increased significantly, particularly in children and adolescents. E. coli-derived ASNase was approved in 1978 to be used as part of a multiagent chemotherapy to treat ALL. However, the development of hypersensitivity in 10-30% of patients often leads to treatment discontinuation. E. chrysanthemi-derived ASNase (referred to herein as ASNase Erwinia chrysanthemi) is immunologically distinct from E. coli ASNase and therefore does not cross-react with the E. coli enzyme. In 2011, ASNase Erwinia chrysanthemi was approved in the United States for patients who develop hypersensitivity to E. coli-derived ASNase. When indicated, a switch from ASNase E. coli to ASNase E. chrysanthemi allows patients to continue to receive treatment and maintain therapeutic levels of ASNase activity. Therapeutic drug monitoring may help ensure that therapeutic enzyme levels are maintained. Pegylated recombinant ASNase Erwinia chrysanthemi is currently being developed to improve pharmacokinetic properties and reduce immunogenicity.