The use of Erwinia asparaginase for adult patients with acute lymphoblastic leukemia after pegaspargase intolerance.

Asparaginase administration has become a crucial component of front-line pediatric and pediatric-insipired multi-agent regimens for the treatment of acute lymphoblastic leukemia (ALL). The aim of this retrospective study was to assess the safety and feasibility of switching to Erwinia asparaginase after pegaspargase intolerance in adult ALL patients treated at Memorial Sloan Kettering Cancer Center. Our analysis included 10 patients, with a median age of 39 years (range 20-72), male predominance (90%), and a typical B-cell to T-cell ratio (70:30%) for ALL. Nine patients were switched to Erwinia asparaginase after pegaspargase hypersensitivity and one patient after grade 4 hyperbilirubinemia secondary to pegaspargase. With Erwinia asparaginase, no hypersensitivity reactions occurred and no patient developed other known clinical asparaginase-related toxicities. Laboratory adverse effects consisted of mostly mild elevation in liver enzymes. No morphologic relapses have occurred in any patient switched to Erwinia asparaginase in first remission at a follow up of 0.4-34.6 months. These findings are unique in that all of our patients received Erwinia asparaginase after hypersensitivity or intolerance to pegaspargase and 50% of them were older than 40 years of age, a population with very limited Erwinia asparaginase data. Our observations provide preliminary information that treatment with Erwinia asparaginase can proceed as scheduled in adult patients, despite pegaspargase hypersensitivity and possibly liver intolerance.