PrEP With Dr Martin Holt: Unexpected Findings From His Study

According to the Centers for Disease Control and Prevention, approximately 70% of new human immunodeficiency virus (HIV) infections in the United States occur among men who have sex with men (MSM).Pre-exposure prophylaxis (PrEP) plays a key role in HIV prevention in this patient population.

However, a new study of PrEP use among gay and bisexual MSM in Australia showed that increased PrEP use was also unexpectedly associated with decreased condom use among men who were not taking PrEP.2

Consultant360 recently spoke with lead study author Martin Holt, PhD, deputy editor of the Journal of the International AIDS Society and professor at the Centre for Social Research in Health at University of New South Wales in Australia, about these new findings and what they mean for the prevention of sexually transmitted infections (STIs) among MSM.

Consultant360: What is the role and importance of HIV PrEP use and related forms of prevention among MSM?

Martin Holt: I think PrEP is really important. For years, we have not had a viable and acceptable prevention option for HIV-negative MSM who can’t or won’t use condoms (such as men who find them difficult or uncomfortable to use, or those who lose their erection when they put a condom on).

Conservative critics often paint these men as reckless or uncaring about HIV, but I reject that interpretation. The majority of research I have seen and been involved in suggests that most of these men remain concerned about HIV, but we have not been able to offer them a viable prevention option. PrEP is clearly very acceptable to many of these men and is highly effective. This is a welcome breakthrough.

C360: Could you tell us more about your study and how it came about?

MH: The Gay Community Periodic Surveys are a longstanding, community-based behavioral surveillance network, conducted in Australia’s largest cities for over 20 years. Gay and bisexual men are recruited from gay community events and venues by trained peers, supplemented by online recruitment. Participants complete an anonymous questionnaire about their sexual behavior, relationships, HIV testing, drug use and engagement with health care. As PrEP rollout was being planned in Australia, we adapted the questionnaire to track PrEP awareness and use. The survey data also allowed us to see how condom use changed as PrEP was introduced.

The journal article reports on changes in a 5-year period (2013 to 2017) during which Australia’s largest states—New South Wales and Victoria—made PrEP available to tens of thousands of gay and bisexual men through publicly funded studies.

C360: Your study ultimately found that a rapid increase in PrEP use was accompanied by an equally rapid decrease in condom use. What factors might contribute to this? And how does this relate to STI acquisition?

MH: Rapidly increasing PrEP use was due to the rollout of large, publicly funded PrEP studies, which made PrEP free or highly subsidized to participants. PrEP was targeted to gay and bisexual men at increased risk of HIV, and our results (and those from the PrEP studies) indicate they were successfully engaged.

We didn’t really expect to see condom use decline so quickly among men who were not taking PrEP, but it did. This could be for a number of reasons, such as:

  • The rapid increase in the number of PrEP users, with whom non-PrEP-users might (safely) have sex.
  • The background trend in declining condom use, which has been happening for at least 15 years.
  • A perception among non-PrEP-users that sex without condoms has become generally safer, because PrEP use by others has increased so rapidly
  • Temporarily destabilized norms about casual sex during PrEP rollout. Rapid PrEP rollout has disrupted existing prevention practices, and it will take a while for them to settle down again as gay and bisexual men decide what they find acceptable.

As we acknowledge in the article, declining condom use may make it easier for STIs to be transmitted. PrEP users in Australia are already engaged in very regular screening for STIs (every 3 months), so if they acquire an STI it can be diagnosed and treated very quickly. That may not be the case for non-PrEP-users, who may not engage with sexual health care very often. We need to encourage them to test regularly to manage STIs in the community.

C360: What do you hope that clinicians learn from your study? What are the key takeaways?

MH: I hope that clinicians will continue to talk about PrEP to eligible patients. In my view, our research does not suggest we should reconsider introducing PrEP. On the contrary, it suggests we have a long way to go to achieve optimal coverage among men at high risk of HIV.

Clinicians can support their patients as they navigate the new prevention domain, encouraging them to choose an effective prevention strategy that is acceptable to them, including condoms, PrEP, and undetectable viral load (using HIV treatment to prevent transmission). They can also provide a supportive ear for men who are struggling to adapt to the new rules of engagement between casual sex partners.

C360: Are there any educational gaps when it comes to HIV prevention and PrEP use in physicians who may prescribe it?

MH: Australia, like the United States, initially endorsed daily PrEP use, but recently our prescribing guidelines have been changed to incorporate event-based dosing. This was shown to be highly effective in the IPERGAY study, led by French researchers.3 This involves taking 2 pills a few hours before sex, then a pill a day for the next 2 days. This may be a more attractive option for those who are concerned about taking medication every day, or who have periodic episodes when they are very sexually active and may be at risk of HIV (such as during party seasons or while on vacation). I think it would be good for prescribers to be aware of this option.

For our coverage of Dr Holt’s study, click here.

—Christina Vogt


1. HIV among gay and bisexual men. Centers for Disease Control and Prevention. Page last updated on February 27, 2018. Accessed on June 15, 2018.

2. Holt M, Lea T, Mao L, et al. Community-level changes in condom use and uptake of HIV pre-exposure prophylaxis by gay and bisexual men in Melbourne and Sydney, Australia: results of repeated behavioral surveillance in 2013–17 [Published online June 6, 2018]. Lancet HIV.

3. Molina JM, Capitant C, Spire B, et al; ANRS IPERGAY Study Group. On-demand preexposure prophylaxis in men at high risk for HIV-1 infection. N Eng J Med. 2015;373:2237-2246. doi: 10.1056/NEJMoa1506273