Pharmacokinetics of 13-cis-Retinoic acid in high-risk neuroblastoma patients

13-cis-Retinoic acid is a differentiation agent for neuroblastoma cells and is a part of post-consolidation therapy for high-risk patients. The effectiveness of this therapeutic approach is currently under study. 26 patients with high-risk neuroblastoma treated at Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology were included in the study of 13-cis-Retinoic acid pharmacokinetics by high-performance liquid chromatography assay with ultraviolet detector depending on the method of administration of drug (swallowed capsules or opened capsules before administration). This study is supported by the Independent Ethics Committee and approved by the Academic Council of the Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology. The current study showed that the therapeutic concentration of > 2 μM when taking 13-cis-Retinoic acid at a dose of 160 mg/m²/day was achieved in two groups, regardless of the method of drug administration. However, plasma concentrations of 13-cis-Retinoic acid at 4 hours after administration on the 14th day of therapy were higher in the group of patients who swallowed the capsules (4.1 ± 1.8 μM), compared to those who could not do it (1.9 ± 1.5 μM) (p = 0.022). The introduction into the clinical practice of therapeutic drug monitoring of 13-cis-retinoic acid in high-risk neuroblastoma patients with an assessment of peak concentration and dose adjustment of the following courses may be an important point in the attempt to optimize postconsolidation therapy and improve prognosis.