By: Caroline Thomas, Peduli Hati Bangsa, March 3rd, 2023
What does HIV prevention mean by Pre-exposure Prophylaxis?
Prophylaxis has the definition of preventing infection with drugs. Exposure is an event that creates a risk of transmission.
So pre-exposure prophylaxis means the use of drugs to prevent infection before engaging in risky activities.
Pre-Exposure Prophylaxis, or PrEP for short, is an HIV prevention option used by HIV-negative people to reduce their risk of becoming infected with HIV.
Today, the research is limited to assessing the efficacy of pre-exposure prophylaxis through sexual intercourse between men or between men and women. Data for other groups such as drug users and transgender users who use the hormone estradiol are limited.
What follows is limited to the use of PrEP at risk of sexual intercourse between men or between men and women.
How is PrEP used?
Since September 2015, WHO has recommended that PrEP containing Tenofovir be offered as an additional prevention option for people who are at risk of HIV infection. The two PrEP combination options recommended by WHO are:
- Tenofovir dengan Emtricitabine (FTC); atau
- Tenofovir dengan Lamivudine (3TC).
Both of these combination options are delivered by oral. There are no dietary rules for using the PrEP combination drug. There are no dietary restrictions meaning that the PrEP combination medication can be taken with or before meals or on an empty stomach.
By 2022 WHO is also recommending offering long-acting blood-sustaining injectable Cabotegravir (also known as long-acting Cabotagravir/CAB-LA) as an additional preventive option for people at risk for HIV infection. Currently CAB-LA is not yet available in Indonesia.
There are two situations for HIV prevention using PrEP, which are:
- Engaging in risky activities that only happen once.
- When there is potential for daily exposure
According to WHO, of these 2 conditions, the following are options for how to start and stop PrEP:
- Individuals engaging in occasional risky activities may start PrEP using 2 doses of either PrEP combination from 2 to 24 hours before the potential exposure. Thereafter the drug is used once daily for up to two days after the last sexual exposure.
- Individuals with potential daily exposure can take PrEP once daily for 7 days prior to potential exposure. Thereafter PrEP was used once daily for up to seven days after the last sexual exposure.
Things to watch out for when using PrEP
- New PrEP studies have been limited to assessing the efficacy of PrEP in high-risk sexual activities for HIV infection.
- Data for other risk groups such as drug users and transgender users who use the hormone estradiol are limited.
- PrEP should be part of an overall HIV prevention program including condoms and counselling
- Before taking PrEP, a person should be tested for HIV to make sure that he is not infected with HIV
- All PrEP users should be tested for HIV regularly
- Before taking PrEP, a person should be tested for kidney damage, hepatitis B, hepatitis C, and other sexually transmitted infections
The relationship between PrEP, Hepatitis B and Hepatitis C
- Individuals who are at high risk of HIV infection also have a risk of Hepatitis B (HBV) and Hepatitis C (HCV).
- PrEP services provide an important opportunity for screening for Hepatitis B and C enabling a person to receive appropriate treatment
- It is recommended to perform the HBV surface antigen (HBsAg) test at the start of PrEP or within one to three months after initiation of PrEP, especially in endemic areas.
- It is recommended to perform the HCV antibody test at the start of PrEP or within one to three months after initiation of PrEP. Furthermore, it is recommended to perform HCV antibody tests every 12 months for populations at high risk of infection with HCV
- PrEP can be offered to people with both HBV and HCV
- Although recommended, HBV surface antigen (HBsAg) testing and HCV antibody testing that cannot be performed for some reason should not be a barrier to PrEP initiation.
Recommendations after receiving HBV test results
- If the Hepatitis B surface antigen (HBsAg) test result is non-reactive: WHO recommends HBV vaccination for people at risk of HBV infection
- If the (HBsAg) test result is reactive: Further assessment of eligibility for treatment:
- The eligibility criteria for long-term HBV therapy based on WHO recommendations are people with HBsAg positive or reactive and have evidence of compensated or decompensated cirrhosis; and persons over 30 years of age with persistently above normal ALT levels and evidence of rapid HBV replication (HBeAg positive).
- The eligibility criteria for long-term HBV therapy based on the Indonesian National Guidelines for Hepatitis B Medical Services (PNPK) are HBeAg positive chronic hepatitis B patients with HBV DNA > 2 x 104IU/mL and ALT > 2x the upper limit of normal; or in patients with negative HBeAg, therapy is started in patients with HBV DNA > 2 x 103 IU/mL and ALT > 2x the upper limit of normal.
- WHO and PNPK Hepatitis B Indonesia recommend Tenofovir or Entecavir to suppress HBV.
- PrEP with Tenofovir is also active against HBV. Therefore, for people who need HBV treatment and wish to use PrEP for HIV prevention, Tenofovir-based PrEP should be considered, as it can suppress HBV and prevent HIV.
- In most cases, Tenofovir will be used as lifelong therapy.
- The doctor who treats PrEP and the doctor who treats HBV must jointly manage this case.
Recommendations after receiving HCV test results
- If the HCV antibody test results are non-reactive: It is recommended to perform the HCV antibody test at the start of PrEP or within one to three months after initiation of PrEP. Furthermore, it is recommended to perform HCV antibody tests every 12 months for populations at high risk of infection with HCV
- If the HCV antibody test result is reactive: It is recommended to perform an HCV viral load test and if the result is detectable, it is recommended to proceed to treatment according to applicable guidelines.
This article was adapted and simplified from:
- Differentiated and simplified pre-exposure prophylaxis for HIV prevention. Update to WHO implementation guideline. WHO. 2022.
- Pedoman Nasional Pelayanan Kedokteran Tatalaksana Hepatitis B. 2019