Therapeutic Drug Monitoring, CYP2C9 Genotyping and Phenotyping in the Treatment of Diabetes with Glibenclamide Products

Rational use of glybenclamide products in the treatment of patients with type 2 diabetes remains a high-priority task. The paper offers a summary of the main groups of glibenclamide drugs and describes pharmacogenetics of glybenclamide. Glibenclamide is metabolized by the enzyme cytochrome P450 2C9 (CYP2C9). Individuals with genetically determined low CYP2C9 activity are at an increased risk of hypoglycaemia. Carriers of CYP2C9*3 and CYP2C9*2 alleles tend to have higher concentrations of glybenclamide in blood and increased insulin secretion. Pharmacogenetic testing of patients and drug concentration monitoring using HPLC-MS can help reduce the risk of hypoglycemia during glibenclamide treatment. Based on literature review the authors selected the method characterised by a simple sample preparation procedure, short analysis time, and a wide analytical range for the substances being determined. This method can be useful both for bioequivalence studies and evaluation of glibenclamide products interchangeability. Glibenclamide pharmacokinetics is characterised by high interindividual variability. This may lead to both an increased risk of hypoglycemia and drug inefficacy, therefore, when prescribing glibenclamide, a physician should carefully control the efficacy and safety of drug therapy.