Australia aims to end new HIV infections by 2020, but limited access could hamper hoped-for gains
Australia aims to end new HIV infections by 2020, but limited access to an effective once-daily medication approach could hamper hoped-for gains
Once public health enemy number one, HIV/AIDS has moved out of the spotlight in recent years. The stigma and discrimination still persist, but in the past five years approaches to treatment have considerably matured. In particular, through the introduction of medication-based HIV prevention options.
One of the newest of these options is HIV pre-exposure prophylaxis, or PrEP, a daily oral HIV prevention pill. PrEP targets people who are HIV negative who are at high risk of contracting HIV. This approach sits alongside more traditional prevention strategies such as condom use and goes a step further than the more familiar post-exposure prophylaxis (PEP) treatments.
PrEP is not currently available under Australiaâs regulatory system. Nevertheless, there are legal and affordable avenues through which healthcare providers can provide PrEP to patients who face a high risk of HIV acquisition: off-label prescription with personal importation, or through referral to a demonstration study, although that option is currently only possible in NSW or Victoria.
PrEP currently comprises two antiretroviral drugs, tenofovir and emtricitabine, sold in combined form under the brand name Truvada. Other PrEP options are in the development pipeline. Clinical trials have shown PrEP to be highly effective in preventing HIV, with the highest levels of effectiveness seen in people who adhere well to their pill-taking regimen1. The drugs used in PrEP are approved and listed on the Pharmaceutical Benefits Scheme (PBS) for HIV treatment, but not for the prevention indication.
Although potentially controversial, PrEP has now been added to the lexicon of other established antiretroviral based HIV prevention strategies: post-exposure prophylaxis2 and treatment-as-prevention (TasP). All these strategies sit firmly in the harm-minimisation camp.
New HIV infections in Australia have hovered over 1200 a year for several years, despite ambitious targets being set in all Australian jurisdictions to sustainably reduce transmissions.
In 2014, the ministers for health from around Australia signed a declaration to virtually eliminate new HIV infections by 2020.
Whatâs in an acronym?
PEP is the use of antiretroviral drugs in HIV-negative people who have had a known, or likely, exposure to HIV, to reduce the risk of getting HIV. It is not a morning-after pill, as PEP involves taking antiretrovirals for 28 days, and ideally it should be started within 72 hours of exposure, or the sooner the better.
PEP is available in every Australian jurisdiction, but it is not on the PBS, so the cost is borne by the state governments.
This has an unintended negative effect: when state health institutions are cash-strapped, they may opt to use cheaper drug regimens for PEP. Those regimens may be equivalent in terms of antiretroviral action, but are associated with higher levels of side effects. Bad side effects on a PEP regimen can make individuals less likely to present after an HIV exposure which then increases the likelihood of HIV infection.
Treatment-as-prevention (TasP) refers to the dual benefit of antiretroviral therapy: suppression of viral load in a person with HIV both protects that personâs health and reduces the likelihood of that person transmitting HIV to sexual partners. The protective effect of suppressed viral load has been established in a range of studies, including recent research in gay men3. The risk of transmission from a person with HIV who has suppressed (undetectable) viral load may not be zero, but it is very low. Accordingly, treating people with HIV soon after diagnosis is now viewed as a
sound public health practice4.
These biomedical approaches to HIV prevention â PrEP, PEP and TasP â are designed to partner with condom use and intimate partner sexual negotiations to form a toolbox of interventions to prevent HIV.
The value of PrEP
The specific value of PrEP is that it enables HIV-negative people at high risk of HIV to be proactive in a manner that is removed from the sexual context. Like the oral contraceptive pill, this offers advantages of removing the need for an intervention that risks being forgotten in the heat of the sexual moment. For those who have receptive sex (whether anal or vaginal), PrEP may be particularly empowering as it gives the receptive partner the opportunity to take control of HIV prevention rather than relying on a partner to use a condom or to maintain an undetectable viral load.
Truvada-based PrEP has been submitted to Australiaâs Therapeutic Goods Administration for approval, and to the Pharmaceutical Benefits Advisory Committee to be considered for reimbursement under the Pharmaceutical Benefits Scheme. Australiaâs regulatory system can be slow, however, so a PBS listing that would ensure the affordability of the drugs may be many months away. PrEP has been approved in the United States, Canada, France, Peru, South Africa, Kenya and Israel.
Australian doctors can prescribe PrEP off-label for people at high risk of HIV acquisition. Once a person has a valid prescription, he or she can choose either to fill it at an Australian chemist, at a cost of approximately $10,000 for a year, or personally import generic versions of the drugs.
While prices and exchange rates vary, the estimated cost of importing is around $280 to $760 for a year. Many individuals around Australia are taking advantage of the latter option, which is allowed under TGA regulations5, and AIDS council websites contain information about how to access appropriate online pharmacies.
Doctors do not have to be S100 prescribers to prescribe PrEP off-label, but those inexperienced in HIV medicine may prefer to refer a PrEP-seeking patient to someone with greater experience.
Demonstration studies
In NSW and Victoria there is another option: demonstration studies. These are set up as collaborations between research organisations, state governments and HIV community sector groups. These studies are seeking to enrol thousands of people â chiefly gay men â at high risk of HIV. The studies will both provide access to the PrEP drugs while collecting further data on how the drugs are used in a trial setting that is very close to real life. The NSW
study, EPIC (Expanded PrEP Implementation in Communities in NSW), is already enrolling participants.
PrEP is a new tool that makes it possible to drastically reduce new infections by giving those who recognise their risk behaviour a novel HIV prevention intervention that does not interfere with the spontaneity of sex.
While PrEP is likely to be approved in the near future, it would be inappropriate to delay PrEP access for those at risk when there are legal avenues to make the drugs available either through the studies or through the off-label options. Action now can prevent HIV infections in the future.
Dr Bridget Haire is Post-doctoral Research Fellow, The Kirby Institute, University of NSW, and President of Australian Federation of AIDS Organisations.
References:
- Okwundu Charles, Okoromah Christy. Antiretroviral pre-exposure prophylaxis (PrEP) for preventing HIV in high-risk individuals. Cochrane Database of Systematic Reviews. 2012;7.
- Australasian Society for HIV Medicine [report on the internet]. Sydney (AUST). Post-exposure prophylaxis after occupational and non-occupational exposure to HIV. National Guidelines. December 2013 (cited 2016 April 7). Available from: http://www.ashm.org.au/Documents/Guide%20for%20the%20Management%20of%20Occupational%20and%20Non-Occupational%20Post-Exposure%20Prophylaxis.pdf
- Grulich A et al. HIV transmission in male serodiscordant couples in Australia, Thailand and Brazil. 2015 Conference on Retroviruses and Opportunistic Infections (CROI), Seattle, USA, abstract 1019LB, 2015.
- Kirby Institute [press release on the internet]. Promising news for HIV treatment as prevention: Study finds HIV transmission rare in couples when an HIV positive partner is receiving treatment. 2015 February 26 (cited 13 April). Available from: http://kirby.unsw.edu.au/news/promising-news-hiv-treatment-prevention-study-finds-hiv-transmission-rare-couples-when-hiv
- Australian Government Department of Health. Therapeutic Goods Administration [homepage on the internet]. Canberra (AUST): Personal importation scheme. 015 Nov 27 (cited 2016 Feb 23). https://www.tga.gov.au/personal-importation-scheme.
