From left: Dr. Julio Montaner, co-leader of the project, and Director of the BC-CfE, and Dr. Richard Harrigan, head of genomics research at the BC-CfE
The Vancouver clinic that pioneered treatments for HIV/AIDS now takes on the effects of treatment itself
Over the past two decades Dr. Julio Montaner and his team at the B.C. Centre for Excellence in HIV/AIDS at St Paul's Hospital have helped turn what was once a death sentence into a manageable chronic disease. Now, with genetic testing, the researchers who have been on the front lines since the beginning are taking on the effects of the drugs themselves.
Since the early 1990s, the BC-CfE has decreased HIV/AIDS deaths by 90 per cent in B.C. by developing new medications, combinations of medications, and viral testing.
As laboratory program director and head of genomics research at the BC-CfE, it was Dr. Richard Harrigan who pioneered one of the world’s first drug resistance testing programs in Vancouver, kick-starting the city’s response to the disease. Today, in partnership with Genome British Columbia and Genome Canada, the BC-CfE’s new $5-million program aims to advance genetic testing to further improve quality of life for patients and reduce the likelihood of transmission of drug-resistant HIV.
In what is known as “treatment-as-prevention,” a technique pioneered in Vancouver, drug cocktails decrease viral loads - and, consequently, the risk of transmission of HIV. But harsh side effects from the medication can turn patients off their treatments, rendering them at once more susceptible to the disease itself and to transmitting it to others.
When Walter Hiebert was diagnosed with HIV in 1988, there were few drug options available.
“I was petrified,” confesses Hiebert. People around him were losing the ability to walk, shedding fat and muscle, and even dying of liver failure due to drug side effects. No treatments were without their consequences, and drug resistance was on the rise.
Fast forward two decades, and thanks to the personalized drug cocktails developed in Vancouver, Hiebert – now 56 – works full-time and is planning for his retirement.
Four separate tests are currently required to determine how the four different classes of drugs will affect a patient. The researchers at the BC-CfE have proposed a single, more efficient test.
“Instead of doing four tests, we’re going to put all these tests into one,” explains Dr. Harrigan, who is the project lead for the new program. “But also the new tests will have more sensitivity for picking up low levels of drug resistance within a person.”
What makes treatment increasingly complicated throughout a patient’s life is that the HIV virus is in a constant state of mutation, evolving to resist the effects of the medication.
Testing the genomes of both the virus and the patient can help fix the problem of side effects for the patient and of drug resistance in the virus. In the virus, genetic tests will reveal what drugs will be most effective. In the patients, genetic tests will help guide doctors to choose the least harmful drugs.
“The most significant threat to treatment-as-prevention programs would be if there were widespread transmission of drug-resistant virus,” says Dr. Harrigan. “We’re planning on not letting that happen.”