Assessing the clinical and economic impact of delayed versus early pegaspargase

Background In acute lymphoblastic leukemia (ALL), pegaspargase is included in the backbone of numerous chemotherapy regimens. Treatment-related toxicities can be substantial, often resulting in treatment delays, dose reductions, or early discontinuation. This study aimed to evaluate whether differences in efficacy, safety, and economic outcomes exist between standard dosing and modified approaches involving dose-reduced and delayed administration of pegaspargase. Methods This retrospective, single-center study evaluated hospitalized adult patients who received pegaspargase as part of CALGB 10403 induction course I. Patients were stratified into two groups: 1) full pegaspargase dose 2500 units/m 2 and standard administration on day 4 (Early PEG group), or 2) dose reduced pegaspargase 1000 units/m 2 and delayed administration on day 15 (Delayed PEG group). Results Eight patients (27%) were treated with a reduced dose of pegaspargase on day 15 of induction (Delayed PEG). Median age of the study population was 27 years, and median BMI was 29.6 kg/m 2 . The majority of patients were male (60%), Hispanic (53%), and had a diagnosis of Philadelphia chromosome negative B-ALL (70%). Incidence of grade 3 or higher toxicities was not significantly different between groups. MRD status at the end of induction was similar between groups [Early PEG 12 (55%) vs Delayed PEG 4 (50%), p = 0.51]. Economic outcomes within 30 days were also similar. Conclusion Our study demonstrates comparable incidence of high-grade toxicities and MRD negative status, suggesting that concomitant dose reduction and delay of pegaspargase administration during CALGB 10403 induction does not significantly impact effectiveness, safety, or economic outcomes.