Rates of genetic testing in patients prescribed drugs with pharmacogenomic information in FDA-approved labeling

Pharmacogenetic testing in primary care could bolster depression treatment: A value proposition

Pharmacogenetic testing could reduce the time to identify a safe and effective medication for depression; however, it is underutilized in practice. Major depression constitutes the most common mental disorder in the US, and while antidepressant therapy can help, the current trial -and error approach can require patients to endure multiple medication trials before finding one that is effective. Tailoring the fit of pharmacogenetic testing with prescribers' needs across a variety of settings could help to establish a generalizable value proposition to improve likelihood of adoption. We conducted a study to explore the value proposition for health systems using pharmacogenetic testing for mental health medications through prescribers' real-world experiences using implementation science concepts and systematic interviews with prescribers and administrators from four health care systems. To identify a value proposition, we organized the themes according to the Triple Aim framework, a leading framework for health care policy which asserts that high-value care should focus on three key metrics: (1) better health care quality and (2) population-level outcomes with (3) reduced per capita costs. Primary care providers whom we interviewed said that they value pharmacogenetic testing because it would provide more information about medications that they can prescribe, expanding their ability to identify medications that best-fit patients and reducing their reliance on referrals to specialists; they said that this capacity would help meet patients' needs for access to mental health care through primary care. At the same time, prescribers expressed differing views about how pharmacogenetic testing can help with quality of care and whether their views about out-of-pocket cost would prevent them from offering it. Thus, implementation should focus on integrating pharmacogenetic testing into primary care and using strategies to support prescribers' interactions with patients.

Pretest Video Education Versus Genetic Counseling for Patients With Prostate Cancer: ProGen, A Multisite Randomized Controlled Trial

PURPOSE

Germline genetic testing (GT) is recommended for men with prostate cancer (PC), but testing through traditional models is limited. The ProGen study examined a novel model aimed at providing access to GT while promoting education and informed consent.

METHODS

Men with potentially lethal PC (metastatic, localized with a Gleason score of ≥8, persistent prostate-specific antigen after local therapy), diagnosis age ≤55 years, previous malignancy, and family history suggestive of a pathogenic variant (PV) and/or at oncologist's discretion were randomly assigned 3:1 to video education (VE) or in-person genetic counseling (GC). Participants had 67 genes analyzed (Ambry), with results disclosed via telephone by a genetic counselor. Outcomes included GT consent, GT completion, PV prevalence, and survey measures of satisfaction, psychological impact, genetics knowledge, and family communication. Two-sided Fisher's exact tests were used for between-arm comparisons.

RESULTS

Over a 2-year period, 662 participants at three sites were randomly assigned and pretest VE (n = 498) or GC (n = 164) was completed by 604 participants (VE, 93.1%; GC, 88.8%), of whom 596 participants (VE, 98.9%; GC, 97.9%) consented to GT and 591 participants completed GT (VE, 99.3%; GC, 98.6%). These differences were not statistically significant although subtle differences in satisfaction and psychological impact were. Notably, 84 PVs were identified in 78 participants (13.2%), with BRCA1/2 PV comprising 32% of participants with a positive result (BRCA2 n = 21, BRCA1 n = 4).

CONCLUSION

Both VE and traditional GC yielded high GT uptake without significant differences in outcome measures of completion, GT uptake, genetics knowledge, and family communication. The increased demand for GT with limited genetics resources supports consideration of pretest VE for patients with PC.

The Value of Pharmacogenetics to Reduce Drug-Related Toxicity in Cancer Patients

Many anticancer drugs cause adverse drug reactions (ADRs) that negatively impact safety and reduce quality of life. The typical narrow therapeutic range and exposure-response relationships described for anticancer drugs make precision dosing critical to ensure safe and effective drug exposure. Germline mutations in pharmacogenes contribute to inter-patient variability in pharmacokinetics and pharmacodynamics of anticancer drugs. Patients carrying reduced-activity or loss-of-function alleles are at increased risk for ADRs. Pretreatment genotyping offers a proactive approach to identify these high-risk patients, administer an individualized dose, and minimize the risk of ADRs. In the field of oncology, the most well-studied gene-drug pairs for which pharmacogenetic dosing recommendations have been published to improve safety are DPYD-fluoropyrimidines, TPMT/NUDT15-thiopurines, and UGT1A1-irinotecan. Despite the presence of these guidelines, the scientific evidence showing the benefits of pharmacogenetic testing (e.g., improved safety and cost-effectiveness) and the development of efficient multi-gene genotyping panels, routine pretreatment testing for these gene-drug pairs has not been implemented widely in the clinic. Important considerations required for widespread clinical implementation include pharmacogenetic education of physicians, availability or allocation of institutional resources to build an efficient clinical infrastructure, international standardization of guidelines, uniform adoption of guidelines by regulatory agencies leading to genotyping requirements in drug labels, and development of cohesive reimbursement policies for pretreatment genotyping. Without clinical implementation, the potential of pharmacogenetics to improve patient safety remains unfulfilled.

Genophenotypic Factors and Pharmacogenomics in Adverse Drug Reactions

Adverse drug reactions (ADRs) rank as one of the top 10 leading causes of death and illness in developed countries. ADRs show differential features depending upon genotype, age, sex, race, pathology, drug category, route of administration, and drug–drug interactions. Pharmacogenomics (PGx) provides the physician effective clues for optimizing drug efficacy and safety in major problems of health such as cardiovascular disease and associated disorders, cancer and brain disorders. Important aspects to be considered are also the impact of immunopharmacogenomics in cutaneous ADRs as well as the influence of genomic factors associated with COVID-19 and vaccination strategies. Major limitations for the routine use of PGx procedures for ADRs prevention are the lack of education and training in physicians and pharmacists, poor characterization of drug-related PGx, unspecific biomarkers of drug efficacy and toxicity, cost-effectiveness, administrative problems in health organizations, and insufficient regulation for the generalized use of PGx in the clinical setting. The implementation of PGx requires: (i) education of physicians and all other parties involved in the use and benefits of PGx; (ii) prospective studies to demonstrate the benefits of PGx genotyping; (iii) standardization of PGx procedures and development of clinical guidelines; (iv) NGS and microarrays to cover genes with high PGx potential; and (v) new regulations for PGx-related drug development and PGx drug labelling.

Perception and knowledge of pharmacogenetics among Brazilian psychiatrists

Pharmacogenetics (PGx) can optimize drug therapy in psychiatry and is particularly important in admixed populations. Here we developed and successfully validated a questionnaire for assessing the perception and knowledge of PGx among Brazilian psychiatrists. Overall, the participants showed some familiarity with PGx. Most psychiatrists reported to have knowledge of PGx and recognized its usefulness in psychiatry; however, they declared concerns regarding PGx education, the request of tests and their interpretation, cost-effectiveness, and ethical issues. PGx testing is relatively prevalent in their clinical practice, but education on the topic is lacking. Bivariate analysis revealed significant associations. Psychiatrists > 40 years of age more frequently had a positive perception of other clinicians' familiarity with PGx. Psychiatrists in private health services showed less self-reported competency in the use of PGx testing. Furthermore, women had better perception of PGx education. The present study adds knowledge about PGx in psychiatry and encourages the development of educational and training resources for PGx to improve its clinical implementation.