“The thing that hit me in the face, was that virtually all the events were in those homozygotes” - Dr. C. Michael Gibson, Duke University Dr. Gibson and Dr. Kirtane from Duke University reconsider genetic testing for CYP2C19 based on the GIFT sub-study of GRAVITAS presented last week at ACC. The study clearly showed that [...]
http://www.nytimes.com/2011/02/13/us/13drugs.html?_r=1&hpw The tragic deaths described in these stories seem largely avoidable, given what we know about drug interactions, pharmacogenetics and the DNA testing and software tools we have for managing complex medication regimens. Many of the drug interaction described in this article are well- known. Many more will be predicted only by GeneMedRx. Physicians are [...]
I have to question the conclusions drawn in this study. The number of patients found to have variant alleles does not compute. Of the 5059 patients genotyped, only 25.5% had a variant allele including those patients the authors categorized as unknown. This is the lowest percentage in any large clopidogrel CYP2C19 study to date [...]
It’s been a busy week for personalized medicine! First, the FDA announced a black box for Plavix warning physicians of treament failures in CYP2C19 poor metabolizers representing up to 14% of their patients. See http://www.fda.gov/Drugs/DrugSafety/PostmarketDrugSafetyInformationforPatientsandProviders/ucm203888.htm for more details. Plavix is currently one of the most commonly prescribed medications in the world so the impact of this [...]
“It takes time to move a technology from bench to bedside. When it comes to DNA testing to determine if breast cancer patients are likely to benefit from tamoxifen, that wait needs to end,” stated NFCR President Franklin C. Salisbury, Jr.
JAMA released more research today that further confirms the importance of CYP2D6 testing to determine tamoxifen efficacy. Full details at http://jama.ama-assn.org/cgi/content/short/302/13/1429. The conclusion: Recurrence Rates: 14.9% for extensive metabolizers 20.9% for intermediate metabolizers 29.0% for poor metabolizers This means that Extensive Metabolizers will get the same preventative outcome from tamoxifen as much more expensive aromatase [...]
Ashcraft: Creating Tailor-Made Prescriptions for All Patients Kristine Ashcraft, director of sales and marketing for Genelex Corp. in Seattle, explains how pharmacogenetics can ease the issues that many patients have with their prescription medications. As she says, “medications are prescribed in a one size fits all manner, so some patients get too high of a [...]
The tragic death of Michael Jackson has the potential to create an important “learning moment” for physicians and patients. According to the Journal of American Medical Association, adverse drug reactions are the “4th to 6th leading cause of death” in the US. The published reports of Mr. Jackson’s medications illustrate an important issue- any two drugs may be safe in combination but the cumulative effect of many drugs can be difficult to detect and very dangerous, especially in people with reduced drug processing capacity.
Filed under: Cytochrome P450, Drug Interactions, Personalized Medicine, Pharmacogenetics | Tagged: adrs, adverse drug reactions, Drug Interactions, michael jackson, Personalized Medicine, Pharmacogenetics, pharmacovigilance | 2 Comments »
Pharmacogenomics J. 2009 May 19. Intermediate metabolizer: increased side effects in psychoactive drug therapy. The key to cost-effectiveness of pretreatment CYP2D6 screening? Laika B, Leucht S, Heres S, Steimer W. Institut fÃ¼r Klinische Chemie und Pathobiochemie, Klinikum rechts der Isar, Technische UniversitÃ¤t MÃ¼nchen, MÃ¼nchen, Germany. The cytochrome P450 2D6 (CYP2D6) isoenzyme metabolizes about 25% of [...]