Pharmacists Should Play Key Role in Pharmacogenomics

More than 90% of individuals harbor DNA variants that could affect response to medications.¹ This striking statistic is widely shared when advocating for pharmacogenomics (PGx) testing in clinical practice. A growing body of literature continues to highlight the benefits across the continuum of care when patient-specific genetic factors are used to optimize therapeutic regimens.^2-8 Patients, payers, health care systems, and clinicians can all benefit significantly from fewer adverse reactions, increased patient safety metrics, reduced cost of treatment, improved medication adherence, and decreased lengths of therapy.

National and state pharmacy organizations have been discussing the role of the pharmacist within this space for years.^9-12 It seems like a natural progression for pharmacists to take ownership of PGx given their extensive knowledge base in pharmacokinetics, pharmacodynamics, and pharmacotherapy. Furthermore, pharmacists are often perfectly positioned within interprofessional care teams to provide education on optimal dosing strategies and alternative recommendations based on patient-specific factors.^12-16

Pharmacists have wondered, however, what this means for the average pharmacist whose pharmacy school education did not include PGx. Taking steps toward education and understanding the many barriers to widespread implementation of PGx is a place to start.

Special Considerations for Pharmacogenomics-Related Educational Materials

As with any certificate or training, it is important to consider both lifestyle and learning style. Various national pharmacy organizations offer online self-paced certification courses with discounted pricing for members.^17-18 Some state associations are even creating content themselves or partnering with smaller educational affiliates to provide education sessions at a discounted price for members or meeting attendees.

If a completely self-paced module is not ideal, there are many options to earn a PGx certificate that integrate interactive components. Variations can include literature reviews, facilitated group discussions, blog posts, and patient case presentations. It is also worth considering whether the facilitator has implementation experience to provide insight with forward thinking questions and concerns past the foundational knowledge base.

Pharmacists already working in a specialty practice setting may want to review the curriculum to ensure there is a component that provides a deeper understanding of the specific patient populations they work with. Additionally, some institutions are incentivizing pharmacists to obtain PGx certifications by covering the cost in return for being the pharmacy champion in implementation efforts.¹³

Nontraditional Funding Streams

One of the most significant barriers to widespread utilization of preemptive PGx testing in clinical practice is the coverage of testing from both public and private insurers. The introduction of the Right Drug Dose Now Act in 2022 was an essential step on the national level to recognize the importance of precision medication. The bill aimed to direct funding toward a public awareness campaign on adverse drug events, establish a program to educate health care professionals about PGx testing, and mandate assessment of electronic health records to ensure the capacity to update based upon clinical evidence developments.^20-22 Unfortunately, these proposals did not encompass widespread coverage for PGx tests themselves; moreover, the bill did not move forward.

Given this major limitation, pharmacists can explore funding for PGx testing through nontraditional revenue streams. Grant funding at the national and state level is often directed toward high-risk and high-cost patient populations. A pharmacist could utilize grant funding within their own institutions in various care settings after an analysis of internal obstacles. Questions worth considering include the following:

• What are the most prescribed medications at the institution? Do those medications have actionable drug-gene pairs indicated by the Clinical Pharmacogenetics Implementation Consortium?²³ Does the FDA have recommendations for testing in the drug label?²⁴
• Which patient populations are constantly readmitted or require more frequent follow-up? Are these patients on medications impacted by genetic variations?
• Does the facility serve minority populations that have established variations in drug efficacy based on race or ethnicity?
• Does the institution already provide PGx testing in a smaller capacity (1 gene for 1 medication)? What would be the cost difference to provide a broadPGx panel?
• Does the institution serve a remote patient population that has access to care barriers? Are the medication regimens of these patients likely to be impacted by genetic testing?

Utilizing external funding for a small patient population may be a great starting point for internal conversations surrounding PGx. Does the facility have the infrastructure to support a patient who comes in with results they ordered themselves? How will care be coordinated when PGx results touch a medication outside the pharmacists’ own specialty area? Can the electronic health record be modified to signal when a medication is orrdered for a patient with a clinically significant metabolic pathway that would render the drug inappropriate? These same questions could be presented to payers that fund pilot programs for their high-risk and high-cost patients. Would they be willing to fund testing to determine the clinical and financial outcomes? How would they communicate results across their electronic platforms between payers and pharmacies? Do they employ pharmacists who currently have the bandwidth to operate in the PGx space?

Taking a step back even further, pharmacists with an entrepreneurial spirit or those seeking additional revenue streams could seek funding as an independent consultant. What barriers to care and health equity issues are unique to your state and practice setting? How could PGx testing be utilized to improve outcomes that are meaningful to your specific community and patient populations?

Miscellaneous Considerations

Apart from being a consultant pharmacist whose business model is strictly direct-to-consumer targeting of cash-paying patients, finding a provider champion will be instrumental to success. This provider should not only be familiar with the basics of PGx, but able to help coordinate a working group to facilitate the ordering and sample collection process, develop educational resources for patients and staff, delineate responsibilities for medication management, and refine applicable workflow across the continuum of care.

Because billing for pharmacy services varies widely across the country, pharmacists should take an active role in advocating for the profession to be reimbursed for clinical services, including PGx-related consults. As an example, California introduced the Pharmacogenomics Advancing Total Health for All Act in 2023 that would mandate coverage for PGx testing for Medi-Cal patients if a beneficiary’s condition is known to have a gene-drug or drug-drug-gene interaction that has been demonstrated to be clinically actionable. It would also prevent the need for prior authorization and ensure safe laboratory testing when ordered by a Medi-Cal clinician or pharmacist.²⁵

If we want pharmacists to take ownership of PGx across all practice settings, being paid as a provider will be critical to widespread implementation. Mandating payment at the state level and advocating for PGx to be included within the state pharmacists’ scope of practice will only strengthen our ability to take ownership of this space as it evolves into the standard of care. Pharmacists should own PGx. Now what can you do to make that happen?

References

1. Ji Y, Skierka JM, Blommel JH, et al. Preemptive pharmacogenomic testing for precision medicine: a comprehensive analysis of five actionable pharmacogenomic genes using next-generation DNA sequencing and a customized CYP2D6 genotyping cascade. J Mol Diagn. 2016;18(3):438-445. doi:10.1016/j.jmoldx.2016.01.003

2. Swen JJ, van der Wouden CH, Manson LE, et al; Ubiquitous Pharmacogenomics Consortium. A 12-gene pharmacogenetic panel to prevent adverse drug reactions: an open-label, multicentre, controlled, cluster-randomised crossover implementation study. Lancet. 2023;401(10374):347-356. doi:10.1016/S0140-6736(22)01841-4

3. Pirmohamed M, Burnside G, Eriksson N, et al; EU-PACT Group. A randomized trial of genotype-guided dosing of warfarin. N Engl J Med. 2013;369(24):2294-2303. doi:10.1056/NEJMoa1311386

4. Coenen MJH, de Jong DJ, van Marrewijk CJ, et al; TOPIC Recruitment Team. Identification of patients with variants in TPMT and dose reduction reduces hematologic events during thiopurine treatment of inflammatory bowel disease. Gastroenterology. 2015;149(4):907-917.e7. doi:10.1053/j.gastro.2015.06.002

5. Claassens DMF, Vos GJA, Bergmeijer TO, et al. A genotype-guided strategy for oral P2Y12 inhibitors in primary PCI. N Engl J Med. 2019;381(17):1621-1631. doi:10.1056/NEJMoa1907096

6. Henricks LM, Lunenburg CATC, de Man FM, et al. DPYD genotype-guided dose individualisation of fluoropyrimidine therapy in patients with cancer: a prospective safety analysis. Lancet Oncol. 2018;19(11):1459-1467. doi:10.1016/S1470-2045(18)30686-7

7. Brixner D, Biltaji E, Bress A, et al. The effect of pharmacogenetic profiling with a clinical decision support tool on healthcare resource utilization and estimated costs in the elderly exposed to polypharmacy. J Med Econ. 2016;19(3):213-228. doi:10.3111/13696998.2015.1110160

8. Bank PCD, Swen JJ, Schaap RD, Klootwijk DB, Baak-Pablo R, Guchelaar HJ. A pilot study of the implementation of pharmacogenomic pharmacist initiated pre-emptive testing in primary care. Eur J Hum Genet. 2019;27(10):1532-1541. doi:10/1038/s41431-019-0454-x

9. Haidar CE, Petry N, Oxencis C, Douglas JS, Hoffman JM. ASHP statement on the pharmacist’s role in clinical pharmacogenomics. Am J Health Syst Pharm. 2022;79(8):704-707. doi:10.1093/ajhp/zxab339

10. Pharmacogenomics. National Community Pharmacists Association. Accessed February 27, 2023. https://ncpa.org/pharmacogenomics

11. FSHP position statement: clinical pharmacogenomics (PGx). Florida Society of Health-System Pharmacists. Accessed February 27, 2023. https://cdn.ymaws.com/www.fshp.org/resource/resmgr/website_updates/fshp_statement_pgx__final.pdf

12. Reiss SM; American Pharmacists Association. Integrating pharmacogenomics into pharmacy practice via medication therapy management. J Am Pharm Assoc (2003). 2011;51(6):e64-e74. doi:10.1331/JAPhA.2011.11543

13. Turnbull C, Pearlman R. The evolution of pharmacogenomics. Drug Topics. July 12, 2021. Accessed February 27, 2023. https://www.drugtopics.com/view/the-evolution-of-pharmacogenomics

14. Roosan MR, Lam J. Pharmacists play role in pharmacogenomics clinical services. Pharmacy Times. May 12, 2022. Accessed February 27, 2023. https://www.pharmacytimes.com/view/pharmacists-play-role-in-pharmacogenomics-clinical-services

15. Elewa H, Awaisu A. Pharmacogenomics in pharmacy practice: current perspectives. Integr Pharm Res Pract. 2019;8:97-104. doi:10.2147/IPRP.S180154

16. Ferro WG, Kuo GM, Jenkins JF, Rackover MA. Pharmacist education in the era of genomic medicine. J Am Pharm Assoc (2003). 2012;52(5):e113-e121. doi:10.1331/JAPhA.2012.12149

17. ACCP applied pharmacogenomics certificate registration now open. American College of Clinical Pharmacy. Accessed February 27, 2023. https://www.accp.com/report/index.aspx?iss=0921&art=4

18. Pharmacogenomics certificate. American Society of Health-System Pharmacists. June 9, 2021. Accessed February 27, 2023. https://elearning.ashp.org/products/8883/pharmacogenomics-certificate?utm_term=&utm_campaign=Performance+Max-Recruitment-1-00-4801-60000&utm_source=adwords&utm_medium=ppc&hsa_acc=3985934627&hsa_cam=17288510113&hsa_grp=&hsa_ad=&hsa_src=x&hsa_tgt=&hsa_kw=&hsa_mt=&hsa_net=adwords&hsa_ver=3&gclid=Cj0KCQiAo-yfBhD_ARIsANr56g57FTqii_apxqu9HR2RNxY8s78RqnS9C7M-Sc6ZQ-_sWBdbZ3KBxjQaApMpEALw_wcB

19. Pharmacogenomics testing for veterans (PHASER). VA Diffusion Marketplace. Updated April 2022. Accessed February 27, 2023. https://marketplace.va.gov/innovations/phaser

20. “Right Drug Dose Now” act should help implement better precision medicine. Inside Precision Medicine. March 2, 2022. Accessed February 27, 2023. https://www.insideprecisionmedicine.com/topics/precision-medicine-topic/policy-legislation/right-drug-dose-now-act-should-help-implement-better-precision-medicine/

21. National action plan for adverse drug event prevention. US Department of Health and Human Services, Office of Disease Prevention and Health Promotion. 2014. Accessed February 27, 2023. https://health.gov/sites/default/files/2019-09/ADE-Action-Plan-508c.pdf

22. Right Drug Dose Now Act, HR 6875, 117th Cong (2022). Accessed February 27, 2023. https://emmer.house.gov/_cache/files/5/b/5bda140e-9bc7-4189-bc68-9c5a19d3c783/D7F099E10B7A00C6E737E671B7810199.right-drug-dose-now-act-final.pdf

23. Guidelines. Clinical Pharmacogenetics Implementation Consortium. Updated March 26, 2021. Accessed February 27, 2023. https://cpicpgx.org/guidelines/#:~:text=Each%20CPIC%20guideline%20adheres%20to,assigning%20strength%20to%20each%20prescribing

24. Table of pharmacogenetic associations. FDA. Updated October 26, 2022. Accessed February 27, 2023. https://www.fda.gov/medical-devices/precision-medicine/table-pharmacogenetic-associations

25. Medi-Cal: pharmacogenomic testing. CA AB425. 2022-2023 Session (Ca 2023). Accessed February 27, 2023. https://legiscan.com/CA/text/AB425/2023

About the Author

Corrie L. Sanders PharmD, BCACP, CPGX is president of the Hawaii Pharmacists Association and founder of Huna Health, a pharmacogenomic consulting service.