The World Health Organization (WHO) has issued its first guidance to nations considering providing ARVs (antiretrovirals) to HIV-negative, high risk people. HIV is a retrovirus. Retroviruses are composed of RNA, not DNA; they have an enzyme (reverse transcriptase) which allows them to transcribe their RNA into DNA after getting into a cell, the retroviral DNA can then become an integral part of the host cell’s chromosomal DNA. Antiretrovirals are medications used to manage or control infections caused by retroviruses.
WHO says its recommendations were based on human trials which showed that administering PrEP (pre-exposure prophylaxis) once daily to HIV-negative individuals who are at high risk of becoming infected, is both safe and effective in helping prevent HIV infection.
Clinical trial results showed that PrEP usage can lower HIV infection rates by approximately 40% among men who have sex with men. Patients who took the drug regularly had a 73% lower risk. Among couples where one of them is HIV positive who regularly took PreP, the reduction in risk was 75%.
WHO emphasized that PrEP usage must be accompanied by safe sex practices – consistent use of condoms – as well as regular testing for HIV, getting prompt treatment for STIs (sexually transmitted infection), and counseling.
For PrEP to work properly, adherence is vital – people need to take the medications every day. This may not be easy to achieve, WHO added. The next challenge is to find ways of delivering PrEP in “real life settings” in order to make sure adherence occurs. Adherence means taking the medications according to instructions, which in this case means every day.
Countries planning to introduce PrEP are being encouraged by WHO to initially set up small projects aimed at helping public health workers fully understand the advantages of PrEP.
In these initial projects, antiretroviral medications are administered to people at high risk of HIV infection. An example of a high-risk group includes males or transgender females who have sex with men. The projects need to identify who would benefit the most from PrEP, and find the best ways to make sure they get the medications.
The outcomes of these projects would be evaluated by WHO, which would contribute towards WHO guidelines on antiretroviral usage for the prevention and treatment of HIV infection. WHO plans to issue the guidelines in the middle of next year.
- People receiving PrEP must be HIV-negative. This is important so that future drug resistance is kept to a minimum
- Those using PrEP need to be encouraged to continue using condoms
- Make sure that those seeking PrEP do not have bone disease, kidney disease, or other medical conditions which would make them unsuitable for ARV therapy
- Making sure adverse events are carefully monitored
- Helping those using PrEP remember to take their medications every day
- Making sure that PrEP medications are easily and readily accessible
- Regularly checking the HIV-status of those taking PrEP, and also checking for signs of drug resistance if infection is detected
- For those who stop taking PrEP, ensuring they have access to HIV prevention services
- Help countries find ways of using their resources to best use. This involves gathering more data on the cost-benefits of PrEP
This week, the FDA (Food and Drug Administration), USA, approved ARV usage as part of an HIV prevention strategy, which should be used in combination with safe-sex practices (condom use), regular HIV testing, and counseling. The drug, Truvada, is estimated to cost $13,900 per person per year in the USA. The FDA said that it is the first medication it has approved which is indicated for HIV-negative adults who are at high risk of becoming infected with HIV.
Truvada is produced and marketed by Gilead Sciences.
Written by Christian Nordqvist