Studying the role of inherited and acquired genetic variation in drug response is helping to optimize drug selection and dosing regimens, and is even contributing to the development of new therapeutic agents. Pharmacogenetics and human genomics have merged into pharmacogenomics, bringing to light discoveries regarding genetic variations that may be at the root of variations in drug response. Genomewide association studies are expanding the learnings achieved from earlier focus on individual candidate genes, accelerating the documentation of biomarkers and mechanisms of drug action. The knowledge gained is improving the ability to predict how certain drugs work in individuals and to avoid adverse drug reactions.
Stay current on Internal Medicine; attend a specialty-specific conference.
Pharmacogenomics is beginning to affect how medicine is practiced, and the potential benefits are intriguing. By gaining knowledge of the genetic status of their patients, physicians can better predict how individuals respond to certain drugs. Pharmacogenomics plays an important role in helping to identify responders and non-responders to drugs; this greatly improves the ability to reach the goal of being able to immediately prescribe an appropriate medication at the right dose and treatment duration to achieve maximal therapeutic benefit with minimal adverse effects.
Pharmacogenomic testing is still in an evolutionary stage, and clinical applications are continuing to emerge. So far, just a few clinical scenarios are recommended by the FDA, and most of these are related to cancer and HIV treatments. Breast cancer, colon cancer, anticoagulation, depression, and hypercholesterolemia therapies all have genotypic research that can aid in better prediction of toxicity risks or the likelihood of response to specific treatments.
Clinical medicine, drug development, drug regulation, pharmacology, and toxicology all are being influenced by pharmacogenomics, but at this point, good clinical data to support the use of genetic testing for drug treatment for most diseases are still not yet available and prospective clinical trials are needed to set guides in clinical practice. Scientific, regulatory, and psychological factors must be addressed if pharmacogenomic tests are to become a routine part of clinical practice and be covered by insurance.
FDA-mandated incorporation of pharmacogenomic information in drug labeling is an important step in the acceptance of pharmacogenomics in clinical practice. To aid with acclimating patients, physicians can provide them with education regarding genomic information. Physicians can also promote efforts to incorporate genomic information into standard clinical decision-making. Depending on the therapy, current drug labeling may already contain information on genomic biomarkers. Detail covered in labeling may include drug exposure and clinical response variability, risk for adverse events, genotype-specific dosing, mechanism of action, polymorphic drug target, and disposition genes. Pharmacogenomic information can appear in different sections of the labeling, depending on the actions. Healthcare providers can find a complete listing of FDA-approved drugs with pharmacogenomic information included in their labeling at www.fda.gov/drugs/scienceresearch/researchareas/pharmacogenetics.
For full labeling on thousands of products, visit PDR.net. Stay current on alerts and specific product labeling by providing updated contact information. To have updated drug information, full labeling, and safety warnings integrated into your electronic prescribing system automatically, and at no cost to you, be sure to request PDR drug data feeds, including PDR BRIEF.
Salvatore Volpe, MD, FAAP, FACP, CHCQM
Chief Medical Officer