Interview: Improving Prescribing Among Veterans

Catherine Chanfreau-Coffinier, PhD, explains how pharmacogenetic testing would impact a large proportion of veterans if it was implemented in the VA population.

Please tell us a little about yourself.

I am a health services researcher and a molecular biologist. I first joined the Department of Veterans Affairs (VA) as a postdoctoral fellow in 2015, and I have been an investigator for the VA Informatics and Computing Infrastructure for the past 2 years. My research interest is in evaluating the value of precision medicine for patients, and for Veterans more specifically, and in improving patient care and patient outcomes related to precision medicine. I have a PhD in Molecular Genetics from University Paris South, France, and a PhD in Health Policy and Management from University of California, Los Angeles.

As explained in your study, “Pharmacogenetic variants contribute to individual differences observed in the response to medications and risk of adverse drug reactions.” Why is this testing important in a veteran patient population?

Drugs that have strong interactions with pharmacogenetic variants are commonly used in the veteran patient population. They include medications used in the treatment of chronic mental health, metabolic disease, and chronic pain, such as antidepressants, statins, and opioids. The burden of these health conditions is high in the veteran population. In addition, many patients suffer from comorbid conditions and may receive multiple drugs involved in gene-drug interactions. So, if pharmacogenetic testing was implemented in the VA population, it would impact a large proportion of veterans.

What can health care practitioners, who treat veterans, take away from your study? How can they take your findings and implement it into daily practice?

Patient results from pharmacogenetic testing may add to other clinical factors that are traditionally considered by health care practitioners in prescription decisions. Evidence-based guidelines are already available for more than 70 gene-drug pairs and may help improve drug efficacy and reduce adverse events based on patient test results. However, it is too early to make any recommendation on the systematic use of pharmacogenetics in practice as more evidence is needed about the clinical utility of pharmacogenetics and its impact on patient outcomes.

How do you believe your study findings will impact prescribing practices? How will the change in prescribing practices impact patient care?

One of the goals of our study was to raise provider awareness to the large number of patients who are carrying clinically important pharmacogenetic variants, and the common use of medications involved in gene-drug interactions. On its own, we do not expect that our findings should impact prescribing practices, but they contribute to the evidence evaluating gene-drug interactions. Our work also provides clues on which pharmacogenetic tests are the best candidates to be performed by VA labs based on the volume of patients carrying a variant and receiving the associated drug.

Is there anything else you would like to add?

This study was performed as part of the VA PRIME Care study for the utility of pharmacogenetic testing for the treatment of depression (VA SDR 16-348, PI D.Oslin, VA Durham). I would like to acknowledge my co-authors who include clinicians, researchers, pharmacists, and pathologists. The interdisciplinarity of our team reflects the collaborative efforts across VA services, such as VA Pathology, Pharmacy, and Genomic Medicine Services that will be central in defining and implementing the pharmacogenetic testing services best adapted to the veteran population. 

Reference:
Chanfreau-Coffinier C, Hull LE, Lynch JA, et al. Projected Prevalence of Actionable Pharmacogenetic Variants and Level A Drugs Prescribed Among US Veterans Health Administration Pharmacy Users [published online June 7, 2019]. JAMA Netw Open. 2019;2(6):e195345. doi:10.1001/jamanetworkopen.2019.5345