Pharmacists And Pharmacogenomic Testing In The United States And Its Economic Value Proposition Within The Healthcare System

• By: RASHID, Nazia (Keck Graduate Institute, United States)
• Co-author(s): Dr Nazia Rashid (Keck Graduate Institute, School of Pharmacy and Applied Sciences, Claremont, United States)
  Dr. Gail Orum (Keck Graduate Institute, School of Pharmacy and Applied Sciences, Claremont, United States)
  
• Abstract:

  Introduction: During the last decade, testing patients’ genome (Pharmacogenetic Testing [PGT]) has played an important role in maximizing the benefits of medications and preventing adverse drug reactions (ADRs). Prior to PGT, the traditional approach of prescribing medication involved selecting a drug, identifying the appropriate dose regimen, and observing if the regimen would be the best treatment for the patient. Advancement in technology with the combination of genomic information has provided new opportunities to facilitate optimal treatment for patients and alleviate error in prescribing. Pharmacists are the most accessible healthcare professionals and as such, pharmacists are able to integrate these genetic tests within their services. It is valuable to discuss the current benefits and barriers of PGT in the United States from a pharmacist perspective; additionally, present the economic value proposition of this testing from the profession of pharmacy.
  
  Methodology: Initially, a systematic literature review (SLR) was conducted using databases, such as PubMed and Google Scholar, to identify and highlight the use of PGT in the pharmacy setting. Pharmacogenetics in a pharmacy setting included testing and analysis of a patient’s genetic characteristics to allow for a customization in their respective therapeutic regimen. Articles related to pharmacogenetics in non-pharmacy settings were excluded from the study. Secondly, utilizing the data extracted from the SLR, a cost-offset model was created focusing on PGT being used within oncology. Oncology was chosen since it is highly associated with precision medicine and identifying genetic markers earlier can support better therapy outcomes. Chemotherapy has been the standard of care therapy; however, newer therapies can target the clinical pathway and alleviate the toxic side adverse events and metastatic stages if detected earlier. The cost of oncology therapies is high, thus PGT is needed more, especially if pharmacists can test for these markers.
  
  Results: Literature articles provided background on the most common roles of PGT were lowering risk of ADRs, increasing medication adherence, and improving patient health-care outcomes. Furthermore, it was found that the most common opportunities that PGT presented to the profession of pharmacy were consulting services, point-of-care testing, and interdisciplinary collaboration to facilitate clinical treatment decisions. A cost-offset model with a decision tree analysis was conducted comparing pharmacists conducting PGT vs no PGT within patients with CYP2C19 gene mutation (i.e breast, lung, liver, stomach cancers). It has shown providing this test could be more impactful with therapy outcomes. It was shown that a patient with a CYP2C19 mutation who received the PGT by a pharmacist experienced fewer inpatient days, fewer emergency department visits, and more outpatient visits than did the No-PGT group. CYP2C19 genotyping was cost‐effective or cost‐saving for the healthcare system when evaluated for 12 months and 24 months for those that survived.
  
  Conclusions: There are significant benefits of PGT to reduce incidence of ADRs, improve therapeutic efficacy, and reduce various healthcare costs. A pharmacist is the most accessible healthcare provider for patients, and integrating this valuable testing can change the clinical and economic landscape of treatment for many patients.