Ask a Pharmacist: The ART of Pharmacogenomics and Personalized Medicine

Ask a Pharmacist: The ART of Pharmacogenomics and Personalized Medicine

John, a man recently diagnosed with HIV, waits nervously in his doctor's office while the doctor reviews his computer screen. The doctor turns to John and says, "At our last visit, you mentioned that you wanted to start HIV medicines right away."

John nods, and reminds his doctor of all the reasons why he wanted to start treatment. John also discusses his concerns, particularly his worries around experiencing bad side effects.

The doctor listens carefully and smiles reassuringly. "I'm glad you want to start HIV medicines despite your fears of side effects. The good news is that the tests you took have already helped us choose the most effective HIV treatment regimen with the fewest side effects. Your blood tests suggest that you start taking ..."

Is this a scene from the future? Not exactly! HIV treatments (and the way we select them) have advanced rapidly since the discovery of the virus in the 1980s. Even though regimens have gotten simpler and more powerful, adverse effects are still one of the primary reasons people discontinue antiretroviral therapy. In one U.S. cohort study, up to 18% of patients had stopped antiretroviral therapy (ART) due to adverse effects. In other cohort studies, the percentage of people stopping ART due to adverse effects is much higher. Approximately 51% of persons had discontinued or changed therapy due to adverse effects in a Swiss cohort, for example, while in UK and Italian cohorts, 51% and 58% respectively had changed stopped ART due to adverse effects -- during the first year!

Enter the era of personalized medicine. The National Genome Project defines personalized medicine as a practice that "uses a person's individual genetic profile to guide decisions made in regard to the prevention, diagnosis, and treatment of disease." "Pharmacogenomics" is a subset of personalized medicine that focuses on using genetic information to guide the selection of drug therapy, and pharmacogenomic testing may be helpful to identify HIV-positive individuals at risk for ART side effects, just as in the scenario above.

This excerpt was cross-posted with the permission of BETAblog.org. Read the full article.