Table of ContentsView AllTable of ContentsPrEP Usage in the U.S.PrEP and Condom UseCan PrEP Fail?Does Adherence Matter?
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Table of Contents
PrEP Usage in the U.S.
PrEP and Condom Use
Can PrEP Fail?
Does Adherence Matter?
In 2021, a new injectable form of PrEP called Apretude (cabotegravir) was approved for use, protecting from HIV with just one shot every two months. Premarket studies suggest that people who take Apretude are 69% less likely to get HIV than even those who take Truvada.
With such effective preventive tools at our disposal, it may seem reasonable to ask if people need to worry about condoms if they are on PrEP,
This article takes an unbiased look at the real-world effectiveness of PrEP and some of the factors that may reduce its efficacy. It also explains the potential risks of ditching condoms and whether it’s possible to get HIV even if you do take PrEP 100% as prescribed.
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PrEP Usage in the United States
PrEP can work exceptionally well in preventing HIV, but it only works if you use it. And a lot of people aren’t.
In 2020, just 25% of the 1.2 million Americans who could benefit from PrEP were taking it. Many were at high risk of infection, such asmen who have sex with men (MSM)or couples inserodiscordant relationships(where one partner has HIV but the other does not).
Although many people qualified for PrEP are aware of its benefits, they often chose to avoid it due to concerns about cost, side effects, impact on insurance, or “not feeling at risk” of HIV.Others are perfectly happy touse condoms, and others express displeasure at the thought of having to take a pill every day.
Studies show thattransgender women, who are at extremely high risk of HIV, are generally the less likely to know about PrEP and less likely to use it if they do (due to a general distrust of medical authority).This is concerning given that no less than 42% of transgender women in the United States have HIV.
Limitations of PrEPPrEP is intended solely to protect people from getting HIV. It does not protect against any othersexually transmitted infection (STI). To this end, condoms—whetherinternalorexternal—still afford the best protection against most STIs.
Limitations of PrEP
PrEP is intended solely to protect people from getting HIV. It does not protect against any othersexually transmitted infection (STI). To this end, condoms—whetherinternalorexternal—still afford the best protection against most STIs.
Does PrEP Reduce Condom Usage?
When PrEP was first proposed as a preventive strategy, some public health professionals expressed concerns that it would encourage users to practicecondomless safe(previously known as unprotected or unsafe sex).
Studies have shown that the opposite may be true.
Two different studies—theiPrEX OLE studyconducted in the United States, South America, Thailand, and South Africa, and theU.S. PrEP Demonstration studyinvolving MSM couples in New York and San Francisco—both reported that PrEP resulted in less condomless sex rather than more.
According to the PrEX OLE study, condomlessreceptive (“bottom”) anal sexdecreased from 34% to 25% after PrEP was started. Similarly, the U.S. PrEP Demonstration study reported a decrease in both the number of anal sex partners and the incidents of condomless anal sex.
This shouldn’t suggest that PrEP will automatically reinforce safer sex practices in all at-risk groups. This is especially true in younger people, particularly younger MSM.
Why Gay Men Are at Increased Risk of HIV
PrEP and Condoms in Young MSM
Younger people taking PrEP tend to have lower rates of treatment adherence and are more likely to engage inhigh-risk sexual activitiesthan older people. On top of this, high rates of syphilis, gonorrhea, and chlamydia among younger peopleadd to the likelihood of HIV infection, which may all but erase the benefits of PrEP.
A 2016 study from the Adolescent Medicines Trial Network (ATN) for HIV/AIDS Interventions reported that 90% of MSM aged 18 to 22 engaged in condomless anal sex while on PrEP and that the incidence increased the more adherent a person was to treatment.
PrEP has never been endorsed as a stand-alone strategy. Other means of protection are recommended, especially among people at high risk of HIV infection (including but not limited to MSM, transgender women, injecting drug users, and serodiscordant couples).
These concerns were amplified when four high-profile cases of PrEP failure were reported between 2017 and 2018. In each instance, the men were said to have been fully adherent to treatment based on the following circumstances:
In three of the four cases, PrEP failure resulted in the transmission of a drug-resistant strain of HIV. For two of the cases, the HIV strain that they were infected with was multi-drug resistant.
What Is Transmitted Resistance?Transmitted resistance is a situation in which a person with a drug-resistant HIV strain passes it to a partner. As a result, the partner will have “inherited” the resistance and will be less responsive to certain HIV drugs even though they have never been on treatment.
What Is Transmitted Resistance?
Transmitted resistance is a situation in which a person with a drug-resistant HIV strain passes it to a partner. As a result, the partner will have “inherited” the resistance and will be less responsive to certain HIV drugs even though they have never been on treatment.
How Much Adherence Is Enough?
The problem is that it is not always clear how much PrEP adherence is “enough” to afford this level of protection.
On the one hand, a comprehensive study conducted in 2013 concluded that 80% adherence to oral PrEP (roughly six missed doses every month) equates to 100% effectiveness.
On the other, the IPERGAY study also conducted in 2013 found that the “on-demand” use of PrEP—in which two pills are taken two to 24 hours before sex and one pill is taken every 24 hours thereafter until sex is concluded—affords the nearly same level protection as daily PrEP.And this, despite the fact that only 43% of the participants took the drugs as prescribed.
While this strongly suggests that PrEP is pretty fool-proof, the results are not consistent, especially among at-risk females.
Research suggests that PrEP may offer less protection from HIV in females despite high levels of adherence. Compared to concentrations of Truvada in rectal tissues, the concentration of Truvada in vaginal tissues tends to be significantly—and sometimes impactfully—lower.
This disparity—paired with isolated cases of PrEP failure—illustrates that the risk of HIV, however low, is present.
The VerdictBased on the available research, there is no clear-cut line between when PrEP provides near-perfect protection and not-so-perfect protection from HIV. As effective as PrEP can be, there is no way to responsibly say when condomless sex may be “safe.”
The Verdict
Based on the available research, there is no clear-cut line between when PrEP provides near-perfect protection and not-so-perfect protection from HIV. As effective as PrEP can be, there is no way to responsibly say when condomless sex may be “safe.”
Summary
As such, there is no way to reliably say at what level of drug adherence or in which situations it may be “safe” not to use condoms.
A Word From Verywell
If you are having trouble taking oral PrEP as prescribed, speak with your healthcare provider about switching to Apretude, mainly if you are at high risk of getting HIV.
18 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Centers for Disease Control and Prevention.Preventing HIV with PreP.U.S. Food and Drug Administration.FDA approves first injectable treatment for HIV pre-exposure prophylaxis.Centers for Disease Control and Prevention.Core indicators for monitoring the ending the HIV epidemic initiative: National HIV surveillance system data reported through June 2024.Adams JL, Shelley K, Nicol MR.Review of real-world implementation data on emtricitabine-tenofovir disoproxil fumarate as HIV pre-exposure prophylaxis in the United States.Pharmacotherapy.2019;39(4):486–500. doi:10.1002/phar.2240Rolle CP, Rosenberg ES, Siegler AJ, et al.Challenges in translating PrEP interest into uptake in an observational study of young black MSM.J Acquir Immune Defic Syndr. 2017 Nov 1;76(3):250–8. doi:10.1097/QAI.0000000000001497Restar AJ, Kuhns L, Reisner SL, et al.Acceptability of antiretroviral pre-exposure prophylaxis from a cohort of sexually experienced young transgender women in two U.S. cities.AIDS Behav. 2018;22(11):3649–57. doi:10.1007/s10461-018-2127-0Centers for Disease Control and Prevention.Fast facts: HIV and transgender people.Miller RL, Strzyzykowski T, Lee KS.Structural effects on HIV risk among youth: A multi-level analysis.AIDS Behav.2018;22(11):3451–67. doi:10.1007/s10461-018-2031-7Hosek SG, Rudy B, Landovitz R, et al.An HIV preexposure prophylaxis demonstration project and safety study for young MSM.J Acquir Immune Defic Syndr. 2017;74(1):21-29. doi:10.1097/QAI.0000000000001179Knox DC, Anderson PL, Harrigan PR, Tan DH.Multidrug-resistant HIV-1 infection despite preexposure prophylaxis.N Engl J Med2017;376(5):501–2. doi:10.1056/NEJMc1611639Markowitz M, Grossman H, Anderson PL, et al.Newly acquired infection with multi-drug resistant HIV-1 in a patient adherent to pre-exposure prophylaxis.J Acquir Immune Defic Syndr. 2017;76(4):e104–e106. doi:10.1097/QAI.0000000000001534Thaden JT, Gandhi M, Okochi H.Seroconversion on preexposure prophylaxis: A case report with segmental hair analysis for timed adherence determination.AIDS. 2018;32(9):F1–F4. doi:10.1097/QAD.0000000000001825Hoornenborg E, Prins M, Achterbergh RCA, et al.Acquisition of wild-type HIV-1 infection in a patient on prep with high intracellular concentrations of tenofovir diphosphate: A case report.Lancet HIV. 2017;4(11):e522–e528. doi:10.1016/S2352-3018(17)30132-7Panichsillapakit T, Smith DM, Wertheim JO, Richman DD, Little SJ, Mehta SR.Prevalence of transmitted HIV drug resistance among recently infected persons in San Diego, CA 1996-2013.J Acquir Immune Defic Syndr. 2016;71(2):228-36. doi:10.1097/QAI.0000000000000831Haberer JE, Baeten JM, Campbell J, et al.Adherence to antiretroviral prophylaxis for HIV prevention: A substudy cohort within a clinical trial of serodiscordant couples in East Africa.PLoS Med.2013;10(9):e1001511. doi:10.1371/journal.pmed.1001511Molina JM, Capitant C, Spire B, et al.On-demand preexposure prophylaxis in men at high risk for HIV-1 infection.N Engl J Med.2015;373(23):2237–46. doi:10.1056/NEJMoa1506273Patterson KB, Prince HA, Kraft E, et l.Penetration of tenofovir and emtricitabine in mucosal tissues: Implications for prevention of HIV-1 transmission.Sci Transl Med.2011;3(112):112re114. doi:10.1126/scitranslmed.3003174Rodger A, Cambiano V, Bruun T, et al.Risk of HIV transmission through condomless sex in serodifferent gay couples with the HIV-positive partner taking suppressive antiretroviral therapy (PARTNER): Final results of a multicentre, prospective, observational study.Lancet.2019;393(10189):2428-38. doi:10.1016/S0140-6736(19)30418-0
18 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Centers for Disease Control and Prevention.Preventing HIV with PreP.U.S. Food and Drug Administration.FDA approves first injectable treatment for HIV pre-exposure prophylaxis.Centers for Disease Control and Prevention.Core indicators for monitoring the ending the HIV epidemic initiative: National HIV surveillance system data reported through June 2024.Adams JL, Shelley K, Nicol MR.Review of real-world implementation data on emtricitabine-tenofovir disoproxil fumarate as HIV pre-exposure prophylaxis in the United States.Pharmacotherapy.2019;39(4):486–500. doi:10.1002/phar.2240Rolle CP, Rosenberg ES, Siegler AJ, et al.Challenges in translating PrEP interest into uptake in an observational study of young black MSM.J Acquir Immune Defic Syndr. 2017 Nov 1;76(3):250–8. doi:10.1097/QAI.0000000000001497Restar AJ, Kuhns L, Reisner SL, et al.Acceptability of antiretroviral pre-exposure prophylaxis from a cohort of sexually experienced young transgender women in two U.S. cities.AIDS Behav. 2018;22(11):3649–57. doi:10.1007/s10461-018-2127-0Centers for Disease Control and Prevention.Fast facts: HIV and transgender people.Miller RL, Strzyzykowski T, Lee KS.Structural effects on HIV risk among youth: A multi-level analysis.AIDS Behav.2018;22(11):3451–67. doi:10.1007/s10461-018-2031-7Hosek SG, Rudy B, Landovitz R, et al.An HIV preexposure prophylaxis demonstration project and safety study for young MSM.J Acquir Immune Defic Syndr. 2017;74(1):21-29. doi:10.1097/QAI.0000000000001179Knox DC, Anderson PL, Harrigan PR, Tan DH.Multidrug-resistant HIV-1 infection despite preexposure prophylaxis.N Engl J Med2017;376(5):501–2. doi:10.1056/NEJMc1611639Markowitz M, Grossman H, Anderson PL, et al.Newly acquired infection with multi-drug resistant HIV-1 in a patient adherent to pre-exposure prophylaxis.J Acquir Immune Defic Syndr. 2017;76(4):e104–e106. doi:10.1097/QAI.0000000000001534Thaden JT, Gandhi M, Okochi H.Seroconversion on preexposure prophylaxis: A case report with segmental hair analysis for timed adherence determination.AIDS. 2018;32(9):F1–F4. doi:10.1097/QAD.0000000000001825Hoornenborg E, Prins M, Achterbergh RCA, et al.Acquisition of wild-type HIV-1 infection in a patient on prep with high intracellular concentrations of tenofovir diphosphate: A case report.Lancet HIV. 2017;4(11):e522–e528. doi:10.1016/S2352-3018(17)30132-7Panichsillapakit T, Smith DM, Wertheim JO, Richman DD, Little SJ, Mehta SR.Prevalence of transmitted HIV drug resistance among recently infected persons in San Diego, CA 1996-2013.J Acquir Immune Defic Syndr. 2016;71(2):228-36. doi:10.1097/QAI.0000000000000831Haberer JE, Baeten JM, Campbell J, et al.Adherence to antiretroviral prophylaxis for HIV prevention: A substudy cohort within a clinical trial of serodiscordant couples in East Africa.PLoS Med.2013;10(9):e1001511. doi:10.1371/journal.pmed.1001511Molina JM, Capitant C, Spire B, et al.On-demand preexposure prophylaxis in men at high risk for HIV-1 infection.N Engl J Med.2015;373(23):2237–46. doi:10.1056/NEJMoa1506273Patterson KB, Prince HA, Kraft E, et l.Penetration of tenofovir and emtricitabine in mucosal tissues: Implications for prevention of HIV-1 transmission.Sci Transl Med.2011;3(112):112re114. doi:10.1126/scitranslmed.3003174Rodger A, Cambiano V, Bruun T, et al.Risk of HIV transmission through condomless sex in serodifferent gay couples with the HIV-positive partner taking suppressive antiretroviral therapy (PARTNER): Final results of a multicentre, prospective, observational study.Lancet.2019;393(10189):2428-38. doi:10.1016/S0140-6736(19)30418-0
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Centers for Disease Control and Prevention.Preventing HIV with PreP.U.S. Food and Drug Administration.FDA approves first injectable treatment for HIV pre-exposure prophylaxis.Centers for Disease Control and Prevention.Core indicators for monitoring the ending the HIV epidemic initiative: National HIV surveillance system data reported through June 2024.Adams JL, Shelley K, Nicol MR.Review of real-world implementation data on emtricitabine-tenofovir disoproxil fumarate as HIV pre-exposure prophylaxis in the United States.Pharmacotherapy.2019;39(4):486–500. doi:10.1002/phar.2240Rolle CP, Rosenberg ES, Siegler AJ, et al.Challenges in translating PrEP interest into uptake in an observational study of young black MSM.J Acquir Immune Defic Syndr. 2017 Nov 1;76(3):250–8. doi:10.1097/QAI.0000000000001497Restar AJ, Kuhns L, Reisner SL, et al.Acceptability of antiretroviral pre-exposure prophylaxis from a cohort of sexually experienced young transgender women in two U.S. cities.AIDS Behav. 2018;22(11):3649–57. doi:10.1007/s10461-018-2127-0Centers for Disease Control and Prevention.Fast facts: HIV and transgender people.Miller RL, Strzyzykowski T, Lee KS.Structural effects on HIV risk among youth: A multi-level analysis.AIDS Behav.2018;22(11):3451–67. doi:10.1007/s10461-018-2031-7Hosek SG, Rudy B, Landovitz R, et al.An HIV preexposure prophylaxis demonstration project and safety study for young MSM.J Acquir Immune Defic Syndr. 2017;74(1):21-29. doi:10.1097/QAI.0000000000001179Knox DC, Anderson PL, Harrigan PR, Tan DH.Multidrug-resistant HIV-1 infection despite preexposure prophylaxis.N Engl J Med2017;376(5):501–2. doi:10.1056/NEJMc1611639Markowitz M, Grossman H, Anderson PL, et al.Newly acquired infection with multi-drug resistant HIV-1 in a patient adherent to pre-exposure prophylaxis.J Acquir Immune Defic Syndr. 2017;76(4):e104–e106. doi:10.1097/QAI.0000000000001534Thaden JT, Gandhi M, Okochi H.Seroconversion on preexposure prophylaxis: A case report with segmental hair analysis for timed adherence determination.AIDS. 2018;32(9):F1–F4. doi:10.1097/QAD.0000000000001825Hoornenborg E, Prins M, Achterbergh RCA, et al.Acquisition of wild-type HIV-1 infection in a patient on prep with high intracellular concentrations of tenofovir diphosphate: A case report.Lancet HIV. 2017;4(11):e522–e528. doi:10.1016/S2352-3018(17)30132-7Panichsillapakit T, Smith DM, Wertheim JO, Richman DD, Little SJ, Mehta SR.Prevalence of transmitted HIV drug resistance among recently infected persons in San Diego, CA 1996-2013.J Acquir Immune Defic Syndr. 2016;71(2):228-36. doi:10.1097/QAI.0000000000000831Haberer JE, Baeten JM, Campbell J, et al.Adherence to antiretroviral prophylaxis for HIV prevention: A substudy cohort within a clinical trial of serodiscordant couples in East Africa.PLoS Med.2013;10(9):e1001511. doi:10.1371/journal.pmed.1001511Molina JM, Capitant C, Spire B, et al.On-demand preexposure prophylaxis in men at high risk for HIV-1 infection.N Engl J Med.2015;373(23):2237–46. doi:10.1056/NEJMoa1506273Patterson KB, Prince HA, Kraft E, et l.Penetration of tenofovir and emtricitabine in mucosal tissues: Implications for prevention of HIV-1 transmission.Sci Transl Med.2011;3(112):112re114. doi:10.1126/scitranslmed.3003174Rodger A, Cambiano V, Bruun T, et al.Risk of HIV transmission through condomless sex in serodifferent gay couples with the HIV-positive partner taking suppressive antiretroviral therapy (PARTNER): Final results of a multicentre, prospective, observational study.Lancet.2019;393(10189):2428-38. doi:10.1016/S0140-6736(19)30418-0
Centers for Disease Control and Prevention.Preventing HIV with PreP.
U.S. Food and Drug Administration.FDA approves first injectable treatment for HIV pre-exposure prophylaxis.
Centers for Disease Control and Prevention.Core indicators for monitoring the ending the HIV epidemic initiative: National HIV surveillance system data reported through June 2024.
Adams JL, Shelley K, Nicol MR.Review of real-world implementation data on emtricitabine-tenofovir disoproxil fumarate as HIV pre-exposure prophylaxis in the United States.Pharmacotherapy.2019;39(4):486–500. doi:10.1002/phar.2240
Rolle CP, Rosenberg ES, Siegler AJ, et al.Challenges in translating PrEP interest into uptake in an observational study of young black MSM.J Acquir Immune Defic Syndr. 2017 Nov 1;76(3):250–8. doi:10.1097/QAI.0000000000001497
Restar AJ, Kuhns L, Reisner SL, et al.Acceptability of antiretroviral pre-exposure prophylaxis from a cohort of sexually experienced young transgender women in two U.S. cities.AIDS Behav. 2018;22(11):3649–57. doi:10.1007/s10461-018-2127-0
Centers for Disease Control and Prevention.Fast facts: HIV and transgender people.
Miller RL, Strzyzykowski T, Lee KS.Structural effects on HIV risk among youth: A multi-level analysis.AIDS Behav.2018;22(11):3451–67. doi:10.1007/s10461-018-2031-7
Hosek SG, Rudy B, Landovitz R, et al.An HIV preexposure prophylaxis demonstration project and safety study for young MSM.J Acquir Immune Defic Syndr. 2017;74(1):21-29. doi:10.1097/QAI.0000000000001179
Knox DC, Anderson PL, Harrigan PR, Tan DH.Multidrug-resistant HIV-1 infection despite preexposure prophylaxis.N Engl J Med2017;376(5):501–2. doi:10.1056/NEJMc1611639
Markowitz M, Grossman H, Anderson PL, et al.Newly acquired infection with multi-drug resistant HIV-1 in a patient adherent to pre-exposure prophylaxis.J Acquir Immune Defic Syndr. 2017;76(4):e104–e106. doi:10.1097/QAI.0000000000001534
Thaden JT, Gandhi M, Okochi H.Seroconversion on preexposure prophylaxis: A case report with segmental hair analysis for timed adherence determination.AIDS. 2018;32(9):F1–F4. doi:10.1097/QAD.0000000000001825
Hoornenborg E, Prins M, Achterbergh RCA, et al.Acquisition of wild-type HIV-1 infection in a patient on prep with high intracellular concentrations of tenofovir diphosphate: A case report.Lancet HIV. 2017;4(11):e522–e528. doi:10.1016/S2352-3018(17)30132-7
Panichsillapakit T, Smith DM, Wertheim JO, Richman DD, Little SJ, Mehta SR.Prevalence of transmitted HIV drug resistance among recently infected persons in San Diego, CA 1996-2013.J Acquir Immune Defic Syndr. 2016;71(2):228-36. doi:10.1097/QAI.0000000000000831
Haberer JE, Baeten JM, Campbell J, et al.Adherence to antiretroviral prophylaxis for HIV prevention: A substudy cohort within a clinical trial of serodiscordant couples in East Africa.PLoS Med.2013;10(9):e1001511. doi:10.1371/journal.pmed.1001511
Molina JM, Capitant C, Spire B, et al.On-demand preexposure prophylaxis in men at high risk for HIV-1 infection.N Engl J Med.2015;373(23):2237–46. doi:10.1056/NEJMoa1506273
Patterson KB, Prince HA, Kraft E, et l.Penetration of tenofovir and emtricitabine in mucosal tissues: Implications for prevention of HIV-1 transmission.Sci Transl Med.2011;3(112):112re114. doi:10.1126/scitranslmed.3003174
Rodger A, Cambiano V, Bruun T, et al.Risk of HIV transmission through condomless sex in serodifferent gay couples with the HIV-positive partner taking suppressive antiretroviral therapy (PARTNER): Final results of a multicentre, prospective, observational study.Lancet.2019;393(10189):2428-38. doi:10.1016/S0140-6736(19)30418-0
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