Background: Pegylated form of E. coli derived asparaginase (PEG) is a crucial component of pediatric ALL therapy. Patients who develop a hypersensitivity (HSR) reaction with PEG receive an alternative form - Erwinia asparaginase (EA). However, an international shortage in 2017 had made it challenging to treat these patients. We have developed a comprehensive strategy to address this need.
Patients and methods: This is a single center, retrospective analysis. All patients receiving PEG were premedicated to reduce infusion reactions. Patients who developed HSR underwent PEG desensitization. Patients were compared to historic controls.
Results: Fifty-six patients were treated within the study period. There was no difference in the frequency of reactions before and after the adoption of universal premedication (p = 0.78). Eight patients (14.2%) developed either ≥ Grade 2 HSR or silent inactivation and 5 patients (62.5%) successfully underwent desensitization. The remaining three patients received EA asparaginase. This intervention led to a decrease in PEG substitution, with 3 patients (5.3%) requiring EA compared to 8 patients (15.09%) in the pre-intervention period. (p = 0.11) PEG desensitization was more cost effective than EA administration.
Conclusion: PEG desensitization is a safe, cost effective, and practical alternative in children with ALL and a Grade 2 or higher HSR.
Keywords: Desensitization; Erwinia; PEG asparaginase; asparaginase; premedication; shortage.