Clinical and regulatory considerations in pharmacogenetic testing

Refinement of a pharmacogenomics app for dosing guidelines for oncology: findings from the usability evaluation

Background

This study extended a precision medicine clinical decision support mobile application (app) for use with oncology medications. Two gene variants (CYP2D6 and DPYD) associated with pharmacogenomic dosing algorithms in oncology was added to a prototype app. Usability of the app was evaluated. The use of smartphones and mobile apps for prescribing medications has exponentially increased since the introduction of physician order entry. Decision support apps have improved provider performance and studies have shown broader adoption is crucial for the success of these tools. Therefore, successful use of mobile apps will depend on perceptions of users. Rogers' Diffusion of Innovation theory will be the guiding framework for this study.

Methods

The main research variable is usability as measured by effectiveness, efficiency, and satisfaction. A mixed method design was used. The setting was inpatient and outpatient oncology practices within North Carolina. The sample included registered nurses and nurse practitioners within the oncology field. A functioning mobile app was extended based on the Clinical Pharmacogenetics Implementation Consortium (CPIC) guidelines to address the most common gene variants seen in oncology patients. Usability testing is divided into two main categories, inspection and testing methods. Prior to the field study, a heuristic evaluation was conducted. This evaluation inspected the user interface, comparing the elements and aspects of it to a set of principles, heuristics, as a guideline to evaluate the usability of the mobile app.

Results

The testing evaluation was conducted with a sample of 51 health care providers to evaluate usability, measured by the System Usability Scale and open-ended questions. Descriptive statistics was used to summarize usefulness and end-user perceived ease of use. In addition, a thematic analysis of the open-ended questions was conducted.

Conclusions

The development of this mobile app is relevant to nurses who have prescriptive privileges, as well as an educational tool for nurses to understand the rationale behind prescribing certain medications and alternate dosages by providing specific recommendations. Translation of precision medicine into practice will benefit patients by improving care, reducing adverse reactions, and lowering costs.

Pharmacogenomic biomarker information differences between drug labels in the United States and Hungary: implementation from medical practitioner view

Pharmacogenomic biomarker availability of Hungarian Summaries of Product Characteristics (SmPC) was assembled and compared with the information in US Food and Drug Administration (FDA) drug labels of the same active substance (July 2019). The level of action of these biomarkers was assessed from The Pharmacogenomics Knowledgebase database. From the identified 264 FDA approved drugs with pharmacogenomic biomarkers in drug label, 195 are available in Hungary. From them, 165 drugs include pharmacogenomic data disposing 222 biomarkers. Most of them are metabolizing enzymes (46%) and pharmacological targets (41%). The most frequent therapeutic area is oncology (37%), followed by infectious diseases (12%) and psychiatry (9%) (p < 0.00001). Most common biomarkers in Hungarian SmPCs are CYP2D6, CYP2C19, estrogen and progesterone hormone receptor (ESR, PGS). Importantly, US labels present more specific pharmacogenomic subheadings, the level of action has a different prominence, and offer more applicable dose modifications than Hungarians (5% vs 3%). However, Hungarian SmPCs are at 9 oncology drugs stricter than FDA, testing is obligatory before treatment. Out of the biomarkers available in US drug labels, 62 are missing completely from Hungarian SmPCs (p < 0.00001). Most of these belong to oncology (42%) and in case of 11% of missing biomarkers testing is required before treatment. In conclusion, more factual, clear, clinically relevant pharmacogenomic information in Hungarian SmPCs would reinforce implementation of pharmacogenetics. Underpinning future perspective is to support regulatory stakeholders to enhance inclusion of pharmacogenomic biomarkers into Hungarian drug labels and consequently enhance personalized medicine in Hungary.

Integrating pharmacogenetic testing into primary care

Introduction

Pharmacogenetic (PGx) testing has greatly expanded due to enhanced understanding of the role of genes in drug response and advances in DNA-based testing technology development. As many primary care visits result in a prescription, the use of PGx testing may be particularly beneficial in this setting. However, integration of PGx testing may be limited as no uniform approach to delivery of tests has been established and providers are ill-prepared to integrate PGx testing into routine care.

Areas covered

In this paper, the readiness of primary care practitioners are reviewed as well as strategies to address these barriers based on published research and ongoing activities on education and implementation of PGx testing.

Expert Commentary

Widespread integration of PGx testing will warrant continued education and point-of-care decisional support. Primary care providers may also benefit from consultation services or team-based care with laboratory medicine specialists, pharmacists, and genetic counselors.