Engaging Students in Pharmacogenetics: Patient Case Studies Using the PharmGKB Website

Cytochrome P450 (CYP) enzymes are important regulators of drug efficacy and toxicity. Genetic variation in CYP isoforms can impact how well patients respond to medications or experience unwanted toxicities. PharmGKB is an online pharmacogenomics resource that collates the latest data and clinical guidelines on genetic variation and drug responses. The purpose of this lesson was to develop an interactive, case-based activity that demonstrated how pharmacogenetics can be used to influence the prescribing of medications. This lesson was provided to 71 students during a two-hour online interactive session. The lesson consisted of 1) a didactic lecture on pharmacogenetic principles, 2) an overview of the PharmGKB website by the instructor, and 3) patient cases that used the PharmGKB website to answer questions and make recommendations about drug therapy. Patient cases explored the impact of genetic variation in CYP enzymes on patients prescribed medications for different diseases including depression (citalopram, CYP2C19), pain (codeine, CYP2D6), organ transplantation (tacrolimus, CYP3A5), and viral infection (efavirenz, CYP2B6). Four additional cases are included in this lesson. Students reviewed the patient cases in small groups, used PharmGKB to answer questions and design treatment plans, and presented their recommendations to instructors and other students. Based on pre-/post-lesson assessment questions and student feedback, we conclude that an interactive, group-based activity can be used to teach basic principles of pharmacogenetics and connect students to online resources for drug dosing.