 Designed to treat acute lymphoblastic leukemia, or ALL, Pegaspargase is an important and effective treatment option for both pediatric and adult patients. Pegaspargase is a modified form of the anti-ALL enzyme therapy L asparaginase, derived mainly from E. coli. Unlike the native enzyme, Pegaspargase is conjugated with polyethylene glycol, or Pegalated, which offers various advantages, such as providing Pegaspargase with a prolonged circulation time, allowing for less frequent administration every two weeks, and it may reduce immunogenicity compared with native or non-pegalated L asparaginase. Extensive evidence shows that in adults and children newly diagnosed with ALL, intramuscular or intravenous administration of Pegaspargase is an effective first-line treatment as part of a multi-agent chemotherapy regimen. It is also beneficial in patients with relapsed ALL, who have hypersensitivity to E. coli L asparaginase. Regarding tolerability, Pegaspargase showed a manageable profile in pediatric and adult patients with newly diagnosed ALL. The most common adverse events were generally consistent with those observed with E. coli L asparaginase. A similar tolerability profile was observed in patients with relapsed ALL and hypersensitivity to the native enzyme. Given its potentially reduced immunogenicity and more convenient dosage regimen compared with native L asparaginase, Pegaspargase remains a valuable treatment option for both children and adults with ALL.