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Updated: Jun 21, 2026

Methionine Functionalized Biocompatible Block Copolymers for Targeted Plasmid DNA Delivery
Published on: August 6, 2019
[Carboxypeptidase-G2 administration after high-dose methotrexate. Treatment and drug interactions]
J A Cózar Olmo1, C Martínez Colmenero, I Peláez Pleguezuelos
1Unidad Gestión Clínica de Pediatría, Unidad Oncohematología, Complejo Hospitalario de Jaén, Jaén, España. jcozarolmo@hotmail.com
Abstract:
Methotrexate (MTX) is widely used as anticancer agent in various malignancies, including acute lymphoblastic leukaemia, lymphoma and osteosarcoma. High doses of MTX may cause acute renal dysfunction. Nephrotoxicity is prevented by the use of alkalinization and hydration. More recently Carboxypeptidase-G2, a recombinant bacterial enzyme that rapidly hydrolyzes MTX to inactive metabolites, has become available for the treatment of acute nephrotoxicity. On the other hand, glutamine is usually administered in oncology treatments to avoid other side effects. We report a case of an adolescent who was diagnosed with T lymphoblastic lymphoma. He was receiving treatment with glutamine when the third course of methotrexate was administered (5 g/m(2)) and he suffered a deterioration in his renal function. Carboxypeptidase was used but the methotrexate serum concentration reduction was not satisfactory. The technique to assess the amount of enzyme-inactivated methotrexate by quantification of MTX metabolites is not available in our country, therefore, the concentrations of MTX may be overestimated. The literature was reviewed to study the influence of glutamine on delayed methotrexate elimination which may lead to acute toxicity.
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