Comparing Tolerability and Toxicity of Calaspargase-Pegol and Pegaspargase in Pediatric Leukemia Patients

As of December 2022, calaspargase-pegol is the standard long-acting asparaginase formulation for patients younger than 22 years of age with acute leukemia. This 3-year retrospective evaluation compared real-world safety and efficacy of calaspargase-pegol versus pegaspargase in pediatric patients. Incidence and severity of hypersensitivity reactions, silent inactivation, and common asparaginase-associated adverse effects were collected. A total of 103 patients were included, of whom 50 received calaspargase-pegol and 58 received pegaspargase. Similar rates of symptomatic hypersensitivity reactions (20% vs. 10.3%; P=0.16) and silent inactivation (16% vs. 5.2%; P=0.18) were seen with calaspargase-pegol versus pegaspargase, respectively. However, 13 patients in the calaspargase-pegol group required conversion to short-acting asparaginase compared with 6 patients in the pegaspargase group (26% vs. 10.3%; P=0.03). Most adverse effects were comparable between the 2 groups, except for a lower rate of hyperbilirubinemia with calaspargase-pegol compared with pegaspargase (34% vs. 58.6%; P=0.01). Overall, no significant differences were found between the formulations in terms of rate of hypersensitivity reactions and silent inactivation. However, calaspargase-pegol did require more conversions to short-acting asparaginase therapy. Additional monitoring and preventative measures should be utilized to prevent calaspargase-pegol-associated adverse effects.