PRE-EXPOSURE PROPHYLAXIS (PrEP)
HIV transmission among men who have sex with men (MSM) has been rising in Singapore as it has in most other countries, indicating the need for additional methods at HIV prevention such as PrEP.
PrEP comprises 2 anti-viral medications tenofovir and emtricitabine (TDF & FTC) and is highly effective in reducing the chances of contracting HIV infection. The use of PrEP is now recommended in national guidelines in many countries.
In 2015, the World Health Organisation recommended that PrEP should be offered as an additional prevention choice for people at increased risk of HIV infection as part of combination HIV prevention approaches, and in 2017 published an implementation tool to guide countries on the introduction and implementation of PrEP.
WHAT ARE THE EVIDENCE FOR EFFICACY
Men who have sex with men (MSM)
The iPrEx study was a double-blind, placebo-controlled, multi-centre trial. The TDF/FTC treatment group, who took the PrEP regularly, was associated with a 44% reduction in the risk of HIV acquisition (95% CI, 15-63). When blood samples were tested for the medication, there was a 92% reduction in the risk of HIV acquisition in persons with detectable levels of TDF/FTC versus those without.
The IPERGAY study was a double-blind, multi-centre trial. The on-demand regimen involved taking 2 tablets of TDF/FTC 2 to 24 hours before sex, 1 tablet a day during periods of sexual risk and for 48 hours (two doses) after sex.
The study was stopped early when it showed that 14 people became infected with HIV in the placebo group compared with 2 in the TDF/FTC group, a risk reduction of 86%.
The PROUD study was a randomised, open-label trial in England. A total of 23 participants became infected with HIV over the course of the study; three in the daily TDF/FTC group and 20 in the deferred group. This represents a risk reduction of 86%.
The Partners PrEP trial was a double-blind trial of daily TDF/FTC or TDF in Uganda and Kenya conducted from 2008 to 2010. Compared to placebo, the overall efficacy estimates was 75% for TDF/FTC, and 67% for TDF alone. When blood TDF levels were measured, for participants in the TDF/FTC group, detectable drug was associated with a 90% reduction in the risk of HIV acquisition.
WHAT ARE THE ADVERSE EFFECTS ?
The clinical trials also provided safety information on PrEP. Some people in the trials had early side-effects such as an upset stomach loss of appetite but these were mild and usually went away within the first month.
Some people also had a mild headache. No serious side-effects were observed. You should tell your doctor if these or other symptoms become severe or do not go away.
HOW TO TAKE PrEP?
Daily PrEP - For MSM, heterosexual men and women, sex workers, trans persons
Daily dosing of co-formulated TDF/FTC. This needs to be taken for 7 days before high levels of protection are achieved for both vaginal and rectal exposure to HIV.
On-Demand PrEP – For MSM only
A double dose (two tablets) of co-formulated TDF/FTC to be taken 2-24 hours before potential sexual exposure, to be followed by single doses 24 and 48 hours after the initial dose.
FOLLOW-UP WITH YOUR DOCTOR
Taking PrEP medicines will require you to follow up regularly with your doctor. You will have blood tests for HIV & other STIs and tests to see if your body is reacting well to the medication.
You will also receive counselling to reduce the risk of acquiring HIV. You should take your medicine as prescribed, and your doctor will advise you about ways to help you take it regularly so that it stands the best chance to help you avoid HIV infection.
Tell your doctor if you are having trouble remembering to take your medicine or if you want to stop PrEP.
PrEP is offered as part of a comprehensive STI/HIV prevention package. PrEP does not protect you against other sexually transmitted infections like syphilis, gonorrhoea, chlamydia or herpes.
If you have started taking PrEP, it is important for you to return for regular STI screening. Condoms provide the most effective barrier to HIV and are also the best way of reducing your chances of picking up or passing on other STI.
To use a 4th generation HIV test (either conventional HIV EIA or rapid test kit). If there was a recent high-risk exposure, it is advisable not to rely on a rapid test as these are less sensitive that conventional EIA.
If the last high-risk exposure was within the last 4 weeks, repeat the HIV test after 4 weeks; also check kidney function, syphilis, HBV, HCV, gonorrhoea and chlamydia tests.
SUBSEQUENT VISITS (3 MONTHLY VISITS ARE ADVISED)
HIV, syphilis, gonorrhoea and chlamydia tests. To do kidney function tests every 6 to 12 months.
WHAT ARE THE OPTIONS FOR OBTAINING PrEP?
If you are considering PrEP, you should discuss this with a doctor with experience in HIV or sexual health to help decide if PrEP is right for you. You may obtain PrEP through the local health system.
Your doctor can prescribe Truvada, which is the original brand name combination of tenofovir and emtricitabine manufactured by Gilead. The cost is approximately $400+ per month for Truvada, which may be too expensive for many people.
Another option may be to purchase generic versions of tenofovir and emtricitabine from a reliable online supplier. Generics are copies of brand name drugs. The cost of generic tenofovir and emtricitabine (TDF and FTC) is much less than the brand-name.
In Singapore, you are allowed to bring in or import medicines for personal medical use if the quantity is less than or equal to 3 months’ supply.
For more information on Truvada or generic tenofovir and emtricitabine (TDF and FTC) for PrEP, talk to your doctor, a sexual health clinic or Action for AIDS (AfA).
WHERE CAN I FIND OUT MORE INFORMATION?
Public Clinic (Level 1)*
|Monday to Friday|
8am – 11am
1pm – 4pm
|Women’s Clinic (Level 2)
With effect from 2nd Jan 2020, the Women's Clinic registration hours will be as follow:
Tuesday, Wednesday & Thursday
1pm – 4pm
Evening Clinic (Level 1)
(mixed clinic for men & women)
|Monday & Friday|
4pm – 6.00pm
|Please note that DSC operates by appointments and patients are strongly encouraged to make an appointment with us. Walk-in patients are only seen under emergency situations.|
If you wish to make an appointment, please visit our Appointment Booking page.
We closed on Saturdays, Sundays and Public Holidays.
In case of emergencies outside of our operating hours, please visit the nearest A&E Department.
*The Public Clinic and the Evening Clinic accepts both male and female patients.
**All new cases and existing patients who have not seen a doctor for more than 2 years will be required to see a doctor for consultation