CMEonHIV.com is dedicated to providing online CME presentations (slides with voiceover) on HIV/AIDS for healthcare professionals given by local and international experts to keep you up-to-date on the ongoing developments in the field.
Conference
"Clinical Applications of Pharmacogenetics/Pharmacogenomics in HIV" Dr. Mona Loutfy (biography) English - 2006-01-20 - 42 minutes
(34 slides)
Summary : On behalf of Dr. Elizabeth Phillips, Dr. Mona Loutfy presents the clinical applications of pharmacogentics which is defined as the hereditary response to drugs. There are 3 different types of patients in a clinical setting; those that respond to the particular medication with little to no toxicity, those that respond with strong toxic effects and those that never respond. As genetic predisposition plays a strong role in this response, further research of pharmacogenetics is essential. This could prove useful in precluding unnecessary therapy or detrimental outcomes. Moreover, pharmacogenetics can help us gain insight on disease mechanisms and other therapeutic targets. In summary, the approach of genetically screening patients attempts to individualize treatment options. However, disadvantages do exist when applying pharmacogenetics in clinical practice. Dr. Loutfy takes a closer look at these and distinguishes between pharmacogenetics and pharmacogenomics.
Altered genetics and the effect on drug response are exemplified in cases such as Gilbert’s syndrome and hyperbilirubinemia which are rather benign conditions associated with atazanavir. A more pressing condition linked with a genetic predisposition is known as the abacavir hypersensitivity reaction (HSR). 2 key studies have associated the susceptibility to HSR with the specific HLA type; the HLA-B5701. The patch test for abacavir hypsensitivity has shown promise in diagnosing and preventing HSR. A study by Phillips et al., showed HLA-B5701 patients tested positive in the patch test. Nevertheless, Dr. Loutfy cautions that there are cases where HLA-B5701 individuals were abacavir tolerant. A study by Rauch et al., examined the clinical effectiveness of prospective genetic screening of HLA-B5701 and found that the rate of abacavir HSR significantly reduced. It is important to recognize that there is often a misdiagnosis of abacavir HSR due to its vague phenotype. HSR can manifest as fever, flu-like symptoms, rash, abdominal pain, diarrhea, etc. Most of these symptoms might not be a result of the abacavir but rather other drugs.
The clinical impact and costs of over diagnosing abacavir HSR is significant since it is required to stop all treatments under these circumstances. This ultimately leads to a longer time to viral load suppression and therefore patients are more likely to seek medical attention. In conclusion, Dr. Loutfy addresses the possibility of generalizing this genetic screening for a specific clinic population.
Learning objectives : After viewing this presentation, participants will be able to discuss:
- pharmacogenetics and pharmacogenomics;
- the advantages and disadvantages in applying pharmacogenetics to clinical practice;
- the difficulties in characterizing abacavir hypersensitivity;
- the abacavir patch test;
- the evidence and experience of genetic screening for abacavir hypersensitivity.
USER ACKNOWLEDGES AND AGREES THAT ALL DECISIONS MADE WITH THE ASSISTANCE OR USE OF THE SOFTWARE AND/OR THE WEBSITE AND/OR BASED ON CONTENT FOUND HEREIN WILL BE EXCLUSIVELY THE RESPONSIBILITY OF THE USER.
