Made-in-BC HIV test used worldwide
Gene sequencing determines personalized patient treatment
Vancouver HIV/AIDS experts have developed a new lab test, now being used around the world, to eliminate medication trials-and-errors, saving lives and costs in the process. The test involves genetic sequencing of the virus in HIV patients, which helps predict which drugs will work best for each.
Knowing whether HIV patients will respond to new drugs saves lives and takes the guesswork out of prescribing.
The HIV field is considered to be in the vanguard of such "personalized medicine," said Richard Harrigan, the scientist who led development of the test at the B.C. Centre for Excellence in HIV/AIDS, based at St. Paul's Hospital.
European guidelines calling for the Vancouver gene sequencing approach to be the standard throughout Europe were released only a few days ago, noted Harrigan, director of the centre's laboratories.
Experts in laboratory medicine are coming to Vancouver from all over the world to learn how to implement the process, called HIV V3 Genotyping, for use in their own countries.
On Tuesday, Harrigan worked with Keith McConnell, lab supervisor for the HIV Centre in the Bahamas, who is now training at St. Paul's.
"We want to ensure we have the technologies in place that provide the best patient results in a cost-effective manner," McConnell said. "By using B.C.'s testing methods in our labs, we will be able to quickly and efficiently determine which drug therapies will benefit individual HIV-positive patients. This methodology will also prove cost-effective in the long run because it means we won't be giving those drugs to patients that they may be resistant to."
For the past several months, the B.C. lab has shared the technology with countries in Asia, the United Kingdom, Africa, South America and Europe. Most have now adopted the B.C. method, Harrigan said.
He said the latest test developed here shows whether a patient will respond to a drug called maraviroc, the latest approved drug in a new class of HIV drugs called CCRS antagonists. The drug is given to those who have run out of other options, which happens as patients typically develop resistance or intolerance to drugs.
The local lab is handling about 6,000 patient samples from all provinces in Canada (except Quebec, which has its own lab using the same technology) and also does a similar volume of tests for research studies.
"HIV is a small, wily creature with only nine genes," said Harrigan. "The viral genome is so small that we just have to look at the relevant piece," he said, referring to the fact that the B.C. test costs around $250 and produces results in only a week, while a test used in the U.S. (but not in most other countries) costs $2,000 and does not yield results for about a month.
Harrigan said the Centre for Excellence does the testing for other provinces on a cost-recovery basis. It does not make money selling the DNA sequencing computer programs because its philosophy is that such information should be freely shared with less developed countries struggling with even higher HIV/ AIDS rates.
In B.C., there are about 6,000 patients on HIV drugs and about 400 new cases are diagnosed each year. But it is estimated that there are about 13,000 B.C. residents living with HIV, a quarter of whom are unaware they have the infection.
Under new guidelines released late last year, health care providers are being urged to routinely offer HIV tests to people who are sexually active or have had a sexually transmitted infection, hepatitis C or tuberculosis. The new guidelines are meant to help diagnose infections in those who are not part of a recognized risk group.
Harrigan said those now diagnosed with HIV can probably expect to live a normal lifespan because of the improvements in drug therapy and the accompanying gene testing. "There are about 28 approved drugs and drug combinations, so there are lots of choices now," he said.