[BLOG]: Clinical pharmacogenomics: Meeting the needs of the community through a dedicated clinic
Pharmacogenomics is the study of how differences in DNA affect response to medications. These differences in DNA can help explain why a couple of otherwise similar patients can receive the same medication at the same dose for the same indication and have different responses. The medication may work well for one patient, while the other patient may receive no benefit or experience side effects.
A significant opportunity
In 2013, 738 million outpatient prescriptions in the United States were written for pharmacogenetically high-risk drugs.1A pharmacogenetically high-risk drug is a drug for which a patient’s response may be substantially altered by a specific genetic variation. Examples of high-risk drugs include codeine, clopidogrel, and mercaptopurine. If a patient’s genotype is known when a medication is prescribed to that patient, the prescriber is able to make a more informed decision on whether to treat with a conventional dose, a modified dose, or a different medication altogether. Based on an individual’s unique genomic data, these actions will reduce the risk that a negative drug-related outcome will occur, leading to a safer, more effective treatment for each individual.
Currently, patients and providers obtain genetic results through various mechanisms, including direct-to-consumer genetic testing and personal genomics services. This has created a demand, from both patients and providers, for assistance with understanding and using these genetic results in the most responsible and beneficial way to optimize drug therapy. The pharmacogenomics clinic at NorthShore University HealthSystem (NorthShore) was created in response to this demand from the local community.
The patient experience
Patients may be self- or physician-referred to the clinic to determine whether pharmacogenomics testing is right for them and have the testing ordered, interpreted, and placed in their electronic medical record (EMR) or to better understand test results obtained elsewhere. During a clinic visit, patients are able to interact with genetic counselors, pharmacists specially trained in pharmacogenomics, and medical geneticists.
A patient’s medical history (eg, family history, medical conditions, previous medications), current medication list, and genetic test results are all evaluated when providing the final recommendations. Many of these recommendations are structured around the pharmacogenomic guidelines written by the Clinical Pharmacogenetics Implementation Consortium.2 The recommendations are commonly to choose another agent in the same drug class and could be impacted by the formulary list of an institution or insurance. For example, if a patient has a particular variant the recommendation may be to use rosuvastatin as an alternative to simvastatin to reduce the risk of side effects. The data collected and recommendations made during the clinic visit are placed in the EMR, from which providers can access this information. The ultimate goal of the clinic is to improve the management of patients by individualizing and optimizing drug therapy.