PrEP: a GP’s perspectiveadmin
PrEP: a GP’s perspective
HIV Australia | Vol. 13 No. 2 | July 2015
Fiona Bisshop addresses some common concerns about PrEP and explains that it’s easy to manage with the support of your GP.
PrEP is the latest big thing in HIV prevention. Pre-exposure prophylaxis is the full term, and it represents an effective strategy for protecting yourself against HIV infection.
I would like to give you my perspective on PrEP as a GP who manages HIV infection and sexual health, and sees a lot of sexually active men who are at risk of acquiring HIV.
The reason PrEP has become such a hot topic is that some large-scale international trials have been published which show it is highly effective in preventing HIV transmission.
PrEP is also quite simple to take (it’s a daily pill) and has relatively few side effects, so it’s hardly any wonder guys are starting to come in and ask if they can go onto it.
PrEP should not be confused with PEP (post-exposure prophylaxis) – a 28-day course of antiretroviral tablets which must be started within 72 hours of possible exposure to HIV.
Unlike PEP, PrEP is taken before HIV exposure. The most commonly studied and recommended PrEP is a pill called Truvada, which is a combination of tenofovir and emtricitabine.
Other drugs are being studied too, but there is no good data on these yet so they are not being recommended at this stage.
So why is PrEP necessary? Unfortunately HIV transmission rates are continuing to rise despite public campaigns to raise awareness around safe sex and regular testing.
Condoms don’t work for everyone for a variety of reasons – guys who have erection problems find them difficult to use, some guys find them to be a real turn-off and actually hate them, and they’re not always around when you need them.
The correct use of condoms requires a degree of preparation that doesn’t always fit with everyone’s lifestyle.
There are many guys out there already using ‘informal’ PrEP – perhaps taking left over PEP tablets, or using their partner’s or a friend’s meds, or they may have bought it online or overseas.
The benefit of doing this with medical supervision and advice from a doctor is that they will know how to use it effectively, and will monitor for side effects and possible serious reactions, and ensure regular testing for other sexually transmitted infections (STIs).
Prophylaxis – it’s not a new concept
I have heard people use the term ‘Truvada Whore’, and talk about PrEP in a really negative way, as though it confirms a judgment about a person’s character if they are taking it.
This is really a symptom of society’s attitudes to sex in general. In the 1960s, there was a similar attitude towards women taking the contraceptive pill. It was a new concept and implied a degree of sexual freedom previously unattainable.
Really PrEP is not much different, it’s about empowering an individual to take control of their own health in a way that fits with their lifestyle.
There have been concerns that PrEP is not effective. The evidence would say otherwise.
There are now several large trials and demonstration projects from different countries which show that PrEP is very protective against HIV transmission when it is taken properly.
The iPrEX and PROUD studies looked at daily PrEP use, and Ipergay looked at intermittent PrEP. Overwhelmingly, the results of these trials showed that those people who were actually taking the pills properly were protected.1 2 3
People have been concerned about the potential side effects and risks to health from the medications, but the studies helped to dispel this myth as well.
Some people complained of nausea, headache and weight loss in the first few weeks of taking the pills, but these effects seemed to settle after the first month of use.
I like to explain it this way – the drugs contained in the PrEP pill have been used for many years to treat HIV, and so their side effect profile is quite well described and there are unlikely to be any surprises.
We know that a small proportion of people who are on these drugs long-term may have some drop in their kidney function, but that this generally returns to normal after stopping the drug.
Also most people have a small drop in bone density on the pill, but this does not worsen with long-term use.
You may have heard that PrEP is not available unless you are lucky enough to get into one of the demonstration projects that are running in different cities.
This is not true, as PrEP can be purchased either from local or overseas pharmacies with a doctor’s prescription. Unfortunately it is not yet listed with the TGA (therapeutic goods administration) or the PBS (pharmaceutical benefits scheme) so a local pharmacy has to charge a high price of over $700 a month.
Overseas pharmacies can supply a generic version of high quality for a much lower price of around $130 a month, or $330 when bought in three-month quantities.4 You will need to email them a copy of your prescription.
It may take about two to three weeks for your medication to be delivered after you have put in your online order. Of course if you did manage to get into a local PrEP study then you will be given the drug for free.
An objection raised by some people is that if you get HIV while taking PrEP you will develop resistance to the drugs. I must admit I was worried about this too, but the studies have shown it really isn’t a big issue.
In fact, the only cases of resistance were in people who didn’t realise they were already seroconverting when they started PrEP, and they didn’t actually develop serious resistance mutations anyway.5
So the key to avoiding resistance is to make sure you are most definitely HIV-negative before starting PrEP.
Concerns have also been raised that taking PrEP would lead to more condomless sex and more STIs. In fact the studies have shown this is not the case, and that there was little change in the rates of condom use or STIs in those people taking PrEP.6
Before starting PrEP, I talk to patients about its effectiveness and what the possible side effects are.
I also mention the possible kidney and bone effects, and how best to monitor for these. I order a baseline blood test to check kidney function, and also to make sure you are HIV-negative.
I check you are immune to hepatitis B, and start your vaccination course if necessary. I ask about any other medications you are taking, including over the counter remedies and supplements, in case of interactions.
I also usually ask about other drug use, because if you are taking something like crystal meth regularly then you might need more help with sticking to your daily pill.
The most important thing to understand about PrEP before you start it is that it only works if you take it.
A bottle of PrEP in the medicine cabinet is no good unless you’re opening it every day and swallowing a pill! So I give advice about tricks to help you remember to take it, like pillboxes and phone reminders.
Making sure you’re HIV-negative before you start is so important. If there is any concern that you may still be in the window period for testing, I will probably recommend that we delay starting until we’re sure you haven’t seroconverted.
Symptoms of seroconversion can include sore throat, fever, rash, sore glands, headache and sore joints and muscles. If you were to start PrEP while seroconverting, you would be at risk of developing resistance to the medication, which makes life a little complicated!
For this reason I never rely on the results of a rapid HIV test if seroconversion is suspected prior to starting PrEP, as the rapid tests are not quite as sensitive at that very early stage of infection.
When you first start PrEP the recommendation is that you start it five days before you have condomless sex. This just gives the drug time to get into the rectal tissue so it’s already in place ready to protect you.
I recommend a regular three-monthly STI check-up for all sexually active gay men and other men who have sex with men, checking for syphilis, gonorrhoea, chlamydia, hep C, as well as HIV.
If you’re on PrEP, then I just add a test of kidney function in your regular blood and urine tests. So monitoring PrEP is not that different to a regular STI screening.
The best data we have comes from people who took PrEP every day. The other way to take it is intermittently, that is, just from time-to-time when you anticipate you might need protection.
The Ipergay study looked at intermittent PrEP use, where people took their pills a few hours before sex and for two days afterwards.
It did provide protection, but the guys in the study were quite sexually active and were taking their PrEP on average weekly, which meant that their levels probably didn’t drop to zero in between episodes, so it’s hard to know if it would still be as effective if you were taking it say monthly rather than weekly.
At this stage, there is no recommendation for intermittent PrEP use, and it is something best discussed with your doctor who can look at your individual risk.
How to stop PrEP
If you’ve been taking daily PrEP, the recommendation is that you continue it for 28 days after the last exposure.
Who should take PrEP?
PrEP is suitable for any person who is likely to be exposed to HIV in the future.
I would recommend it for guys who have casual partners and frequent condomless sex, guys who attend sex parties, guys who take drugs like crystal which affect their ability to make rational decisions around protection, guys who can’t use condoms, guys who are regularly getting rectal chlamydia or gonorrhoea, and anyone who has had to ask for a course of PEP.
It’s also recommended for those people with a positive partner who is not on treatment, and for heterosexual couples trying for pregnancy, where one partner is positive.
Who shouldn’t take PrEP?
Really there aren’t many people who can’t take PrEP. It’s not suitable if you have kidney disease. It shouldn’t be taken by anyone who hasn’t had an HIV test and doesn’t know their status already.
PrEP, condoms or both?
I am a strong advocate for the use of condoms, as they protect against a variety of other STIs, but I’m also a realist, and I know that there are many people who are not going to use them in all situations.
Ultimately I believe that every individual who believes they might be at risk of HIV should be able to have the choice of going onto PrEP.
1 Grant, R., Lama, J., Anderson, P., McMahan, V., Liu, A., Pedro Goicochea, L., et al. (2010). Preexposure Chemoprophylaxis for HIV Prevention in Men Who Have Sex with Men. New Engl J Med., 363(27), 2587–2599. doi: dx.doi.org/10.1056/NEJMoa1011205
2 McCormack, S., Dunn, D. (2015). Pragmatic Open-Label Randomised Trial of Preexposure Prophylaxis: The PROUD Study. Presentation delivered at CROI 2015, Seattle, February 23–26. Abstract 22LB.
3 Molina, J., Capitant, C., Charreau, I., Meyer, L., Spire, B., Pialoux, G., et al. (2015). On demand PrEP with oral TDF-FTC in MSM: Results of the ANRS Ipergay trial. Presentation delivered at the 2015 Conference on Retroviruses and Opportunistic Infections (CROI 2015), Seattle, February 23–26. Abstract 23LB.
4 Current estimates for the average price of unsubsidised PrEP in Australia is around $850 for a 30-pill bottle, and around $130 per bottle for generics. See: Australasian Society for HIV medicine (ASHM). Update on HIV PrEP for HIV clinicians. ASHM, Sydney. Retrieved from: www.ashm.org.au/Documents/ASHMPREPCommunique.pdf
5 Lehman, D., Baeten, J., McCoy, C., Weis, J., Peterson, D., Mbara, G., et al. (2015). Risk of drug resistance among persons acquiring HIV within a randomized clinical trial of single- or dual-agent pre-exposure prophylaxis. Journal of Infectious Diseases, 211(8), 1211–1218. doi: dx.doi.org/10.1093/infdis/jiu677
6 Grant, R., Anderson, P., McMahan, V., Liu, A.,Amico, K., Mehrotra, M., et al. (2014). Results of the iPrEx open-label extension (iPrEx OLE) in men and transgender women who have sex with men: PrEP uptake, sexual practices, and HIV incidence. Presentation delivered at the 20th International AIDS Conference, 20-25 July, Melbourne. Abstract TUAC0105LB. Retrieved from: pag.aids2014.org/abstracts.aspx?aid=11143
Dr Fiona Bisshop is a General Practitioner and s100 prescriber at Holdsworth House, Brisbane. She has been working in the area of LGBT health and HIV medicine since 2001.