The placement of clinical pharmacists at the nexus of functional pharmacogenomics and in specialty pharmacy care makes good sense.
Pharmacy practice and the pharmaceutical industry are undergoing dramatic change. One area on the rise is pharmacogenomics (PGx), which is a part of the broader term “precision medicine.”1 Numerous authors have noted that clinical pharmacists are well-positioned, both by training and placement, within the health care delivery system to play an essential role managing these innovative treatments.2-4
Given that many of the recent therapy advancements are centered around patients living with complex, chronic diseases often managed with specialty treatments, the placement of clinical pharmacists at the nexus of functional PGx and in specialty pharmacy care makes good sense.
Pharmacogenomics is a growing and innovative area of health care that is influencing specialty pharmacy practice. This form of precision medicine and related treatments is being driven by advances in genomic testing to inform pretreatment decisions about a given patient’s expected treatment response and adverse event likelihood.1
With such rapid innovation in PGx diagnostic and treatment approaches across a widening expanse of conditions, there is a level of uncertainty for how clinical pharmacists in specialty pharmacy can adapt and add value. Although there are numerous ways in which pharmacists can bring value, we will specifically discuss their role as a “trusted counselor” to minimize certain barriers associated with optimizing precision medicine within the specialty space.5,6
Clinical pharmacists serve to fill certain care and information gaps that are currently acting as barriers to optimizing precision medicine technology and evidence advancement.
Traditional Medicine and the Advent of Precision Medicine
Historically, clinical evidence rested upon the fundamental principles inherent to the randomized clinical trial (RCT), in which promising treatments get compared with a standard (placebo or current standard of care) under controlled conditions and evaluated using deductive statistical inference to evaluate outcomes.
As the gold standard, RCT has associated advances in the development of effective clinical treatments that help the most people the most.7 However, the need to still treat individuals uniquely is never fully addressed using group statistics, no matter how rigorously derived.
Precision medicine changes this dynamic by aligning pharmaceutical development and testing toward acknowledgement and consideration of the individual differences inherent in every person and every treatment response (or nonresponse).
The Precision Pipeline
Targeted therapies associated with precision medicine represent an important advancement in drug development, with oncology being the area of fastest growth.8,9 Additionally, rare diseases are a popular target for newer gene and cell therapies.
Although cell and gene therapies might have the potential to treat a wide scope of diseases, it is estimated that approximately half of these approved gene and cell therapies will be indicated for the treatment of hematological cancers, particularly B-cell lymphomas and leukemias.8
These targeted cancer treatments inhibit the progression of cancer by acting on a more selective range of molecules. Previously available chemotherapies were less selective and, therefore, resulted in killing a much wider range of cancerous and noncancerous healthy cells.8 Targeted therapies, such as these, help reduce the potential secondary damage to healthy tissue, while more precisely attacking cancerous ones.
Although only a few gene and cell therapies are currently available, by 2030, it is projected that 30—60 of these products will have attained FDA approval, with approximately 350,000 to 500,000 patients being treated with this form of precision medicine.9,10 According to the American Society of Gene & Cell Therapy, there are 546 clinical trials involving cell and gene therapies across various stages of development, as of April 15, 2020.11
Because precision medicines have very specific targets, diagnostic testing for specific mutations is key to identifying genetically optimal patients. Without a way to accurately match a patient’s specific genetic abnormality with the correct targeted treatment, even the most detailed will struggle to reach the right patients.
Unfortunately, these diagnostic tests are not often part of routine laboratory tests. For this reason, some precision medicine developers have also become involved with the development of diagnostic tests to identify the genetic mutation being targeted by their product.4
In many cases, the FDA has approved specific diagnostics for use with individual precision medicine products. The prescribing information for precision medicine products often references confirmation of a specific genetic mutation via a companion diagnostic.
A list of currently approved diagnostic tests and their corresponding precision medicine products can be found on the FDA’s website. Failure to confirm genetic mutation by an FDA-approved test may result in insurance denying coverage for the precision medicine product.
Specialty Pharmacy and the Pharmacist as a Trusted Counselor
Specialty pharmacy is where much of the precision medicine and PGx innovation are being delivered. These types of pharmacies and the services they provide are well-positioned to address several key obstacles to more comprehensive implementation and application of effective cell and gene therapies.
Given the Obama administration’s definition of precision medicine as an area that encompasses genomic, environmental, and lifestyle factors, the need to address the environmental and lifestyle factors in unison, with the changing PGx evidence, will be an increasingly important pharmacist function to fill the information and service gaps for consumers.12
Although the focus of nearly all conversations regarding PGx and precision medicine has been on the genomic data and its promised value, some authors have cautioned against an over reliance on the promise of that domain alone for precision medicine. Figure 1 displays the 3 domains consistent with the aforementioned definition, with the patient and clinical pharmacist consultation at the center of the intersection.
Figure 1: Precision Medicine Domains and Examples12
Little has been discussed on how to address the other 2 spheres of social/lifestyle and environment. Precision medicine is still an ongoing project and no clear models for how to integrate the 3 relevant domains with regards to assessing and intervening and the junction of genomics, social/lifestyle, and environment.
Furthermore, it is unclear who will bring and how to bring these domains together within a practical, patient encounter that is consumer friendly. One proposed solution is viewing the pharmacist as a trusted counselor to address the range of topics that might be of patient or even practitioner concern.13
Although opportunities for pharmacists to address environmental risks may be limited, they can certainly play a significant role in addressing some of the social risks, as well as serving as a quality control for the appropriate application of genetic evidence and companion diagnostics. Probably the most obvious social intervention the pharmacists in specialty pharmacy can facilitate is prescription access.
Let us consider 3 overlapping roles in which the pharmacist might function as a trusted counselor:13
The American Society of Health-System Pharmacists (ASHP), a national organization focused on optimizing medication use that represents more than 55,000 patient care providers, which include pharmacists, student pharmacists, and pharmacy technicians, has developed guidelines for effective education and counseling.16
As the costs of genetic testing decline and it becomes more commonplace, the consistent application of companion diagnostics will change how medicine is prescribed, delivered, assessed and paid for.18 As research and development of genetically-targeted medications increase, organizations must develop clear plans for how to successfully evaluate and stay current on this aspect of drug development.
They must also implement processes within the patient-care workflow that assesses and addresses instrumental, informational, and emotional support. Clinical pharmacists with primary counseling functions must maintain their understanding of how to interpret the growing number of genetic tests and their treatment evidence to confidently make recommendations on how this information informs treatment in a manner readily understandable by a range of patients.
Where health care data and care systems allow for the identification of gaps in application of precision practices (eg, companion diagnostics) the clinical pharmacist can serve as a liaison between patient and provider to ensure proper application of the technology. In some cases, this will be to assure application and documentation of the appropriate practice and might include education around the most up-to-date evidence, recommendations, and guidelines.
To meet this need, certain organizations such as PharmGKB and the National Institutes of Health Pharmacogenomics Research Network, are available to provide evidence-based information. The Clinical Pharmacogenetics Implementation Consortium (CPIC) has designed guidelines to support clinicians in optimizing medication therapy based on knowledge of patient genotyping. Numerous CPIC guidelines have been endorsed by various professional societies, including the ASHP.14,15
Table 1 provides a selection of useful resources for remaining current with evidence and practice related to PGx.
Table 1: Resources for PGx Information and Guidelines
Association for Molecular Pathology
Canadian Pharmacogenomic Network for Drug Safety
CDC Public Health Genomics
Clinical Pharmacogenetics Implementation Consortium
Dutch Pharmacogenomics Working Group
European Pharmacogenomics Implementation Consortium
Food and Drug Administration
French Network of Pharmacogenetics
Pharmacogenomics Knowledge Base
Pharmacogenomics Research Network
Royal Australian College of General Practitioners
Pharmacists intersect with the health care system in a wide range of key service areas, including specialty pharmacy. Specialty pharmacy is an area of practice in which patient support needs are often at their highest and where digestible treatment information and gaining access to treatments may be significantly complex.
This is even more true with the level of innovation occurring in the area of PGx and precision medicine in which the pharmacist is likely to be one of the educators. Pharmacists, particularly those in specialty, will need to expand their counseling skills in terms of being an educator, providing accurate information (and correcting misinformation) for patients and caregivers and helping them and their providers make more informed decisions.
If the evidence-based application of this new, high-potential approach to drug development is to be effectively realized, then a critical role of the pharmacist must be to serve as a check point for patients and providers to assure proper delivery. This assurance then becomes one of quality control at both the operational and interpersonal level.