(199) Potential Drug-Drug Interactions in Pediatric Patients with Cancer: A Hospital-Based Prospective Study

Publication Number: 1244

Background: The combination of chemotherapeutic, anti-microbial, and supportive care medications that pediatric oncology patients receive place them at higher risk for drug-drug interactions (DDI). Monitoring and detecting potential DDI in the pediatric oncology population is crucial to reducing complications from adverse events.

Objectives: The primary objective of this study was to examine the prevalence of potential DDIs, both total and clinically relevant, in hospitalized pediatric patients at the oncology unit. The secondary objectives were to describe the most common DDIs in these children and to investigate the risk factors associated with the presence or absence of clinically relevant DDIs.

Methods: A prospective observational study was conducted, with data collected during each patient course of admission at the Amir oncology Hospital affiliated to Shiraz University of Medicine from November 2019 to June 2020. We compared two commonly used drug interaction databases: LEXI INTERACT™, and Drugs.com™.The study did not focus on the clinical consequences of drug interactions, but rather on their potential for occurrence. All patients younger than 18 years-old and taking treatments with two or more drugs at the hospital were included.

Results: Eighty patients were included in this study, 59% were male while 41% were female. The most common malignancy type detected was leukemia, particularly acute lymphocytic leukemia, which accounted for 31% of cases. Most of the potential drug-drug interactions (PDDI’s) were between anti-neoplastic drugs (54%), where 90% of them were moderate, 4.5.% major, and 4.5.% minor. We observed 33% of PDDI were between non-anti-neoplastic drugs, while 50% were type C, 21.5% type B, 14.2% type A, and 14.2% type D, according to Lexi interact analyzer. DDIs between anti-neoplastic- and non-anti-neoplastic drugs accounted for 14.2% of all DDIs , where 66.6% were type C and 33.3% type D. The most common interaction among anti-neoplastic drugs was detected between Methotrexate-Vincristine (MTX-VCR), which may cause liver complications with moderate severity. MTX was the most common drug involved in DDIs, followed by VCR (both with moderate severity).

Conclusions: The study shows a high prevalence of DDIs in pediatric cancer patients in a hospital setting. Physicians and clinical pharmacists should collaborate to develop a routine computer-based screening method to identify and prevent the DDIs risk in hospital settings of developing countries.