NEW YORK (GenomeWeb News) – The US Food and Drug Administration has advised doctors that those administering the AIDS drug abacavir (Ziagen) should also give patients a companion genetic test that can predict whether they will experience a serious and sometimes fatal reaction to the drug.
According to an advisory issued on Thursday, FDA has notified abacavir’s maker, GlaxoSmithKline, that it needs to change the label on the drug to warn that all patients should receive the genetic test human for the human leukocyte allele HLA-B*5701 before beginning therapy.
A genetic test for the HLA-B*5701 allele currently is offered by Laboratory Corporation of America.
FDA said that it has reviewed two studies and determined that patients who carry HLA-B*5701 are at high risk for developing a hypersensitivity reaction. Avoiding use of abacavir in patients positive for the allele will “significantly decrease the risk of developing clinically suspected” hypersensitivity reactions to the drug, FDA continued.
The FDA “took this as an opportunity to underline their support of using safer drugs,” Personalized Medicine Coalition President Edward Abrahams told GenomeWeb Daily News on Thursday. The PMC represents parties including patients, industry, academics, payers, and providers, and focuses advancing the use and adoption of personalized medicine products.
The abacavir HSR reaction is a multi-organ syndrome characterized by symptoms including fever, rash, as well as gastrointestinal, respiratory, and constitutional symptoms.
“It’s another example of the trend towards targeted diagnostics,” Abrahams said of the advisory and the relabeling of the drug. He said this move is important because it aims to “protect against adverse events by using a genetic test,” and because it “supports the mission to make genetic testing more common.”
Greg Downing of the Department of Health and Human Services’ Personalized Healthcare Initiative called the move “a step toward the future that we’re working for – when we can use our personal genetic information to know whether a drug will be effective for us, or dangerous for us – before it is taken.”
A prospective study funded by GlaxoSmithKline found that 61 percent of patients who have the marker will develop the abacavir adverse reaction during treatment with the drug, compared to just 4.5 percent of those without the variation.
The study also found that using the test to decide whether or not to use the drug lowered the number of subjects who had the reaction by more than half, from 7.8 percent to 3.4 percent.