Pharmacist Perspectives on High-Dose Methotrexate Management and Acute Kidney Injury Risk Mitigation in Patients With Lymphoma: Results From a National Survey

Background: A summary of pharmacist-based practices and preferences regarding the prevention and management of high-dose methotrexate (HDMTX) toxicity in patients with lymphoma does not exist. The objective of the study was to describe current practices surrounding management of HDMTX therapy. This was done through a self-administered, web-based, cross-sectional survey of hematology/oncology pharmacists to ascertain practices and individual attitudes about HDMTX therapy management. Responses were summarized with descriptive statistics. Response comparisons were made using Chi-square or Fisher’s exact test for categorical data, and Kruskal-Wallis test for variables on the Likert scale. A total of 175 pharmacists provided 116 eligible surveys [68 (59%) complete responses and 48 (41%) partial responses] for analysis. The Cockcroft-Gault estimated creatinine clearance formula was the most preferred method (61%) to estimate kidney function and determine HDMTX dosing. Respondents would proceed with HDMTX therapy until the predicted risk of AKI, or AKI stage 2 or 3, exceeded 50% and 20%, respectively. Preferred treatment modifications for a high predicted AKI risk after HDMTX exposure included additional prehydration, HDMTX dose reduction, and increased kidney function monitoring, although levels and degrees of agreement varied. Respondents indicated that serum cystatin C-based GFR estimates lacked evidence, accuracy, and practicality in HDMTX therapy management. There was limited familiarity with cell cycle arrest biomarker use during HDMTX therapy. Glucarpidase was considered time-sensitive and highly effective; however, acquisition cost represented a barrier to use, and the optimal dose was felt to be unknown. In conclusion, there is significant heterogeneity in supportive practices and beliefs about the optimal management for patients with lymphoma receiving HDMTX therapy.