Incidence of Exposure of Patients in the United States to Multiple Drugs for Which Pharmacogenomic Guidelines Are Available

Abstract

Pre-emptive pharmacogenomic (PGx) testing of a panel of genes may be easier to implement and more cost-effective than reactive pharmacogenomic testing if a sufficient number of medications are covered by a single test and future medication exposure can be anticipated. We analysed the incidence of exposure of individual patients in the United States to multiple drugs for which pharmacogenomic guidelines are available (PGx drugs) within a selected four-year period (2009–2012) in order to identify and quantify the incidence of pharmacotherapy in a nation-wide patient population that could be impacted by pre-emptive PGx testing based on currently available clinical guidelines. In total, 73 024 095 patient records from private insurance, Medicare Supplemental and Medicaid were included. Patients enrolled in Medicare Supplemental age > = 65 or Medicaid age 40–64 had the highest incidence of PGx drug use, with approximately half of the patients receiving at least one PGx drug during the 4 year period and one fourth to one third of patients receiving two or more PGx drugs. These data suggest that exposure to multiple PGx drugs is common and that it may be beneficial to implement wide-scale pre-emptive genomic testing. Future work should therefore concentrate on investigating the cost-effectiveness of multiplexed pre-emptive testing strategies.

Impact of Pharmacogenetics on Efficacy and Safety of Statin Therapy for Dyslipidemia

“…The benefits of statin therapy have also been demonstrated as primary prevention to reduce ASCVD risks. A recent study of commonly prescribed drugs with known pharmacogenetic considerations demonstrated that simvastatin use was highly prevalent, especially among patients older than 65 years …”

An end to pharmacogenetic exceptionalism

“…Moreover, patients have a nasty habit of having multiple diseases, particularly over the long haul. This overlap supports the idea that all pharmacists must have some basic expertise in pharmacogenetics, regardless of their specialty practice area, and that patients can benefit by having “all” pharmacogenes interrogated in a single test because their chance of being prescribed a high‐risk drug over their lifetime is reasonably high, and everyone's chance of having at least one actionable pharmacogene is extremely high . Although many contributors have mentioned that having more data on gene/drug pairs in their patient populations would be helpful, and it would for many genes and drugs, there are also some penetrant pharmacogenetic defects that have applicability among all patients, regardless of age, gender, disease status, or race: for example, patients who have two null alleles (eg, *5 for CYP2D6 ) cannot express CYP2D6 no matter what else is happening.…”

Development of the PGx‐Passport: A Panel of Actionable Germline Genetic Variants for Pre‐Emptive Pharmacogenetic Testing

“…Patients will receive multiple drug prescriptions with potential gene–drug interactions within their lifetime . It has been estimated that half of patients above 65 years will use at least one of the drugs for which PGx guidelines are available during a 4‐year period, and one fourth to one third will use two or more of these drugs . Logistics and cost‐effectiveness are, therefore, optimized when delivered in a pre‐emptive panel‐based approach; pharmacotherapy does not have to be delayed, awaiting single‐gene testing results and costs for genotyping are minimized, as marginal acquisition costs of testing and interpreting additional pharmacogenes is near‐zero .…”

“…16,18 It has been estimated that half of patients above 65 years will use at least one of the drugs for which PGx guidelines are available during a 4-year period, and one fourth to one third will use two or more of these drugs. 19 Logistics and cost-effectiveness are, therefore, optimized when delivered in a pre-emptive panel-based approach; pharmacotherapy does not have to be delayed, awaiting single-gene testing results and costs for genotyping are minimized, as marginal acquisition costs of testing and interpreting additional pharmacogenes is near-zero. 20 Although a sufficiently powered and well-designed study assessing the (cost-)effectiveness of pre-emptive PGx testing is yet to be concluded, 21 a number of small randomized observational studies indicate promising clinical utility of PGx panel testing.…”