Low Serum Albumin Level Is a Risk Factor for Delayed Methotrexate Elimination in High-Dose Methotrexate Treatment

BACKGROUND: In high-dose methotrexate (HD-MTX) therapy, delayed elimination of MTX from plasma leads to severe adverse effects. However, the risk factors for the delayed elimination of plasma MTX are still unclear. OBJECTIVE: The purpose of this study was to investigate the factors related to the delayed MTX elimination in HD-MTX monotherapy. METHODS: This retrospective study was performed on patients who received HD-MTX monotherapy between April 2009 and March 2019 at the Hiroshima University Hospital. Patients were divided into a "Normal" and a "Delayed" group according to their MTX plasma concentration at 48 or 72 hours after administration. Patient characteristics, dose of HD-MTX, MTX plasma concentration, and adverse effects were analyzed and compared between the 2 groups. RESULTS: = 0.018, respectively). Adverse effects were not significantly different between the 2 groups, excluding renal impairment. CONCLUSIONS AND RELEVANCE: Our study showed that low ALB is a risk factor for delayed MTX elimination in HD-MTX monotherapy. Pharmacokinetic analysis is needed to establish the dose of HD-MTX in patients with a low ALB level.