Safety profile of a single pegylated asparaginase (PEG-ASP) dose in remission induction for acute lymphoblastic leukemia (ALL).

The incorporation of pegylated asparaginase (PEG-ASP) in pediatric and adult acute lymphoblastic leukemia (ALL) protocols remains a worldwide therapeutic approach. However the safety profile remains a challenge, and herein we report the toxicity of an intravenous single dose of 1000 IU/m2 PEG-ASP administered in remission induction for adult ALL patients. Thirty-two patients at median diagnostic age of 32 years (median of 19-65) were included in this analysis. Most patients had B-cell lymphoblastic leukemia (n=26; 78%) and 81% of cases were <55 years at study entry. 75% of patients had <30x109/l leukocyte count at diagnosis and median follow-up was 14 months (range 0.8-69). All grade 3/4 adverse events (AEs) after PEG-ASP administration were observed in 24 patients (75%). The most common grade 3/4 AEs were: decreased fibrinogen (58%), increased bilirubin (31%) and increased GGTP (27%). Clinical manifestations related to PEG-ASP were seen in 9 patients and included: abdominal pain (n=6), thrombosis (n=2), diarrhea (n=1) and pancreatitis (n=1). The median time from PEG-ASP administration to first toxic symptoms was 7 days (range 1-19), and there were also 4 (13%) early induction deaths. All deaths were observed in ≥50-year-old patients after a median of 5 days following PEG-ASP (range 1-9). Three of these four patients had massive obesity. While all expired patients had grade 4 neutropenia and thrombocytopenia at the time of death, sepsis was not present. Administration of PEG-ASP in induction remission for ALL patients resulted in a significant, but mostly reversible hepatotoxicity. This PEG-ASP treatment should be administered with caution for older, obese patients.