Introduction
Inter-individual variability in pharmacological responses to medications poses a significant burden on the capacity of healthcare systems worldwide1. The modern concept of “personalized medicine” aims at its core to facilitate selecting the right drug for the right patient at the right dose with the minimum of adverse drug reactions (ADR)2. ADRs are a serious cause of hospitalizations and deaths in the United States3.The percentage of patients who respond positively to their medications ranges from 25-60%4. Almost 40% of patients suffer from a treatment failure, in the form of negative therapeutic effects and negligible desired benefits, necessitating switching from one medication to another5.
Non-genetic factors, such as age, weight, gender, co-morbid disease states, and drug-drug interactions, are well-documented to contribute to such variability in clinical responses to drugs6. However, genetic variation among individuals remains a principal cause of the heterogeneity of drug responses in practice7. Hence, pharmacogenomics (PG), the integrated analysis of the role of genomics on responses to drugs8, is a promising new approach that targets tailoring therapeutic regimens based on a person’s genetic makeup9, thus improving the efficacy and safety of drug prescriptions10, avoiding ADRs11, and enhancing patient health outcomes12. Most importantly, PG has an immense potential for improving cost-effectiveness of pharmacotherapy13 .
To date, more than 100 medicines have been included in the Food and Drug Administration (FDA) repository of drugs labeled for PG analysis prior to administration14, particularly those with a narrow therapeutic index and a fatal toxic potential15, such as antineoplastic16, anticonvulsant17, and anticoagulant drugs18. However, there remains a slow uptake of PG applications in mainstream clinical care19, and many of the FDA-recommended PG tests are unfortunately not in routine use20. Although criteria for proper clinical actionability of a novel test fundamentally apply to the available PG tests21, including analytic validity22, clinical validity23, and clinical utility24, the alarming limited knowledge and awareness of PG concepts among healthcare providers seem to critically hinder its application25.
The responsibility of healthcare providers in improving the overall quality of clinical care has incentivized recent efforts to integrate PG testing in clinical practice26. Pharmacists and physicians alike are nowadays aware of the need to adjust their clinical roles to become more patient-oriented towards enhancing implementation of personalized pharmacotherapy services27. However, limited resources and poor understanding of PG persist to be a problem in developing countries like Jordan28. Furthermore, there are currently no comprehensive studies exploring correlates of PG practice among the whole stratum of medical students, interns, residents, and specialists, from all fields of medical practice in Jordan. Thus, this study aimed to assess the knowledge, attitude, future expectations, and practice of medical students and clinicians in hospitals in Northern Jordan regarding PG testing, in addition to determining their perceived barriers to its application.