Reaching people living with HIV with care, treatment and support to improve their longevity and quality of life, and to prevent new infections (a concept known as Treatment as Prevention¨, or TasP¨) has helped bring the HIV epidemic under control in British Columbia. TasP¨ is a strategy many countries around the world have adopted. Now, the Canadian expert who developed TasP¨is looking to transfer the success of this initiative to stamp out another global epidemic: hepatitis C.
Dr Julio Montaner, Director of the BC Centre for Excellence for HIV/AIDS (BC-CfE) in Vancouver, will discuss the strategy at the Global Hepatitis Summit in Toronto, Canada (June 14-17). He has seen the remit of his centre expand over recent years to include tackling hepatitis C. He agrees with other experts that the hepatitis C epidemic has two sides: one is the baby boomers (in Canada defined as those born 1945 to 1975) who were infected when younger and represent little risk of onward transmission; and the group of core transmitters (around 30% of those infected) who engage in injection drug use, sex work or high-risk sex practices (whether or not they are HIV infected).
“Of course, we encourage all baby boomers to have a one-time test and treatment if they test positive. However, we recognize through our research that treating this group alone will not stop the epidemic. Targeting the core transmitters will be essential if we are to eliminate hepatitis C in Canada and beyond,” says Dr Montaner.
While the HIV and hepatitis C epidemics share some similarities, there are key differences. Once a person infected with HIV has received consistent and sustained treatment, they will develop an undetectable viral load. It is now widely accepted that undetectable equals uninfectious. This is the concept behind TasP¨. Also of note, current HIV treatment needs to be taken for life, which keeps the virus under control.
In hepatitis C, the new era of directly acting antiviral (DAA) drugs means infected people are cured in 12 weeks or less. However, a person can be re-infected as there is no residual immunity against hepatitis C virus after the treatment is completed. This is to say, the day after cure, an individual is susceptible to be re-infected again, particularly if still involved in high-risk practices.
“When it comes to ending the spread hepatitis C, the impact of Treatment as Prevention¨ will only be optimised if rolled out in combination with appropriate harm reduction measures to prevent re-infection, such as access to supervised injection facilities, provision of clean injecting equipment, and education and support for those engaged in high-risk sexual practices,” says Dr Montaner.
His team is currently running the Per-SVR (pronounced persevere) study that is prospectively assessing the level of harm reduction needed to prevent the spread of hepatitis C. The study will look at people who have had their hepatitis C successfully treated and cured, and their subsequent behaviour. Through this research, it will be possible to determine how injection practices and use of opioid substitution can affect reinfection risk in people injecting drugs, and how high risk sexual practices affect reinfection risk.
The provinces of Ontario and British Colombia are among jurisdictions to have recently lifted their restrictions on DAA drugs (most other provinces and territories have also done so). Previously, only those with advanced liver disease could access hepatitis C treatment as covered through provincial health plans. Now, anyone with any stage can access treatment. Although the cost of treatment is officially secret under agreements between the pharmaceutical industry and the pan–Canadian Pharmaceutical Alliance (pCPA), it is thought one course of curative treatment costs CAN$20,000 per patient.”However, we face a problem with diagnosis rates and access to services particularly among marginalized and most at risk communities,” explains Dr Montaner.”Recent estimates suggest just under half – some 44% – of Canadians with hepatitis C do not know they are infected.”
Previous modelling studies have suggested that if DAA drugs are available with no restrictions, then successful treatment of around 75 per 1,000 people with hepatitis C who inject drugs in Vancouver could halve prevalence in this group within 15 years; if the number treated was around 100 per 1,000, prevalence rates would drop by three quarters in 15 years. Vancouver is estimated to have a very high prevalence (65%) of hepatitis C among people who inject drugs. In other cities with lower prevalence, a lower number of individuals treated would lead to the same effect.
“We need to target the populations who are at higher risk of having hepatitis C and offer low-barrier and accessible means to be tested and treated, within a harm reduction framework,” says Dr Montaner.”This is an exciting time for elimination efforts in Canada, as we have supportive federal and provincial governments in place, in addition to improved access to a newer generation of drugs that treat hepatitis C more rapidly with fewer side effects.”
He adds:”Another crucial step reaching more individuals with treatment is allowing primary care providers – such as general practitioners and nurse practitioners – to screen, diagnose, and treat simple cases of hepatitis C infection. The entire health community must act together to fight this epidemic, improve quality of life for those living with the disease and stop its spread. Just as we were in 2006 with HIV, we are now in a position to say that Treatment as Prevention¨ will work for hepatitis C.”
Recent data published in The Lancet Infectious Diseases by the BC-CfE and the U.S. Centers for Disease Control and Prevention suggested that, contrary to popular beliefs, the biggest expansion of the North America hepatitis C epidemic occurred in the early 1950s -suggesting a possible link to the boom in healthcare practices that at the time entailed the use of reusable glass and metal syringes. This surge was not connected to the peak in injection drug use in the late 1960s, although that certainly played a part in transmission.
“Data suggest that most baby boomers were infected when they were young children, rather than through risky behaviour when older. These results should go a long way to remove this persistent stigma barrier to testing among baby boomers,” says Dr Montaner.”Taking a test could save an individual living with hepatitis C from developing serious liver disease or liver cancer, if they turn out to be infected.”
To interview Dr Julio Montaner, Director of the BC Centre for Excellence for HIV/AIDS in Vancouver, Canada, please contact Caroline Dobuzinskis, Media Relations. T) +1 604 366 6540 E) cdobuzin@bccfe.ca
Alternative Contact: Tony Kirby of Tony Kirby PR Ltd. T) +44 7834 385827 E) tony@tonykirby.com