Since the completion of the Human Genome Project in 2003, there has been a plethora of scientific research in genetics and the molecular characterization of various diseases, such as cancer. President Obama’s announcement and endorsement of precision medicine in the 2015 State of the Union address further mobilized many federal and private institutions to promote, collaborate on, and intensify efforts to use the human genome information to optimize patient care and outcomes. The main goal of the Precision Medicine Initiative was to support research in pharmacogenomics, the delivery of targeted therapeutics, and the sharing of genetic data in electronic health records.
The Food and Drug Administration (FDA) has since developed a website with labeling changes for over 130 medications and includes its recommendations or requirements for pharmacogenetics testing prior to prescribing the medications. The labeling information contains clinical evidence for genotype-guided treatments based on pharmacogenomic information that affects drug exposure and clinical response variability, risk for adverse events, and polymorphic drug target and disposition genes. Similarly, two well-known resources that offer pharmacogenomics information include the Clinical Pharmacogenetics Implementation Consortium (CPIC) and Pharmacogenomics Knowledge Base (PharmGKB). They disseminate actionable recommendations and guidelines to clinicians for genotype-guided therapy for specific drug–gene pairs.
There is also growing evidence that pharmacogenomics and precision medicine are influencing the future of professional health education and clinical practice. We have observed the incorporation of pharmacogenomics in the curricula of medical and pharmacy schools. The national professional entities that recognize the significant role of pharmacogenomics and its impact in the future of health care and how it could lead to improved patient health outcomes include the American Medical Association (AMA), American Society of Health-System Pharmacists (ASHP), and American Association of Colleges of Pharmacy (AACP).
In clinical practice, we have noticed patients who experience subtherapeutic efficacy in spite of receiving maximum daily dosages of their medications, as well as patients who experience severe adverse events from the standard recommended medication dosages. Many pharmacological treatments are complex for the myriad of conditions and diseases that a patient has, not including their genetic variability. As a result, this textbook is created for clinicians who are interested in practicing precision medicine by using the science of pharmacogenomics and making actionable, genotype-guided recommendations to optimize treatments for their patients. Furthermore, this textbook contains updated information about pharmacogenomics resources and the ethical and legal considerations to assist clinicians who are interested in implementing pharmacogenomics in practice settings.
This textbook also includes the fundamentals of pharmacogenomics and therapeutics topics that have the most significant and evidence-based recommendations from scientific and clinical studies. The therapeutics chapters are laid out in a clear and concise format that includes the mechanism of drug–gene interaction, consequences of drug–gene interaction, and genotype-guided treatment recommendations to help clinicians make evidence-based decisions and recommendations. Additionally, the textbook contains tables, figures, and case scenarios in each chapter to stimulate critical thinking and reinforce the main concepts. Each chapter also has a clinical pearls section to highlight and summarize the key takeaways.
Recognizing that research in pharmacogenomics is rapidly increasing, I hope the readers will find the textbook useful in helping them implement and apply pharmacogenomics in their clinical practice. More importantly, I hope the textbook will serve as an essential resource for clinicians who desire to practice precision medicine in order to optimize treatments based on their patients’ genetic variability and promote patient safety.
Jerika T. Lam