Pharmacogenomic Highlights From the PREPARE Study

A new study on the clinical utility of pharmacogenomics (PGx) was recently published in The Lancet. PGx is a form of precision medicine that considers genetic variation in pharmacogenes between individuals and how those variations may affect drug processing and response. There are hundreds of medications in multiple therapeutic areas (mental health, oncology, pain management, cardiology etc.) that are associated with pharmacogenomics.

The PREPARE (Pre-emptive Pharmacogenomic Testing for Preventing Adverse Drug Reactions) study from The Lancet, (2023; 401: 347–56) was a randomized, multi-center trial of almost 7,000 patients seeking care in multiple therapeutic areas. This is a landmark trial that sheds light on the value of PGx for clinical utility and medication safety.

The PREPARE study spanned numerous hospitals, outpatient clinics, and pharmacies in several countries. This study included 12 pharmacogenes in their PGx test and identified at least one actionable genetic variation in 90 to 95% of the studied population. This finding supports other published studies including the Vanderbilt PREDICT study* and the Mayo-Baylor RIGHT 10K study** where pharmacogenomics was found to be relevant to the majority of the studied population. The primary outcome of the PREPARE study showed a 30% decrease in clinically relevant adverse drug reactions (ADRs). Additionally, there was a 70% adoption rate of PGx-based recommendations by prescribing providers based on the patient’s PGx test results. Adverse drug reactions are the 4th leading cause of death in the United States, so the findings in the PREPARE study highlights the importance and effectiveness of using PGx to help decrease ADRs in patients. ***

By using genetic data in appropriate clinical prescribing decisions, we can help decrease patients’ suffering and improve the trial-and-error prescribing, with the goal of optimizing medication regimes earlier. If you would like additional training or education on PGx, multiple resources such as PharmGKB** exist that are free resources for providers. Please join me in next month’s article on, “How to talk to your patients about PGx testing.” 

* Van Driest et al. Clin Pharmacol Ther. 2014 April;95(4): 423-431




Julie Ceno-England, MD is a board-certified family medicine physician with more than 15 years of clinical practice experience. Dr England is currently the Senior Medical Director and VP of Medical Affairs at OneOme LLC, a med tech company located in Minneapolis, MN