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. 2021 Oct-Nov;29(4):399-406.

Challenges and Opportunities for Preexposure Prophylaxis

Mary Catherine Cambou  1 , Raphael J Landovitz  2
Affiliations

Challenges and Opportunities for Preexposure Prophylaxis

Mary Catherine Cambou et al. Top Antivir Med. 2021 Oct-Nov.

Abstract

Despite major advances in the HIV prevention toolbox in the past decade, there remain substantial social, economic, and structural barriers to access to preexposure prophylaxis (PrEP) that prevent a universal, population-level reduction in HIV incidence. Daily oral tenofovir disoproxil fumarate/emtricitabine (TDF/FTC) has been the flagship PrEP regimen, and data support a pericoital/on-demand "2-1-1" dosing schedule for men who have sex with men. Daily oral PrEP with tenofovir alafenamide combined with emtricitabine (TAF/FTC) was approved by the US Food and Drug Administration (FDA) in 2019 for all routes of exposure other than vaginal exposures. The effectiveness of daily oral TDF/FTC has not been consistent in cisgender women outside of serodifferent couples, likely owing to differences in vaginal tissue penetration of PrEP agents resulting in less "forgiveness" of nonadherence. These observations have highlighted the need for additional choices of HIV prevention strategies. Injectable long-acting cabotegravir was recently shown to be superior to daily oral TDF/FTC across risk populations. PrEP studies of islatravir are underway for a monthly oral formulation and a drug-eluting subdermal implant. Lenacapavir, with a novel mechanism of action, is under investigation as a subcutaneous injection at 6-month intervals.

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Figures

Figure 1.
Figure 1.
HIV Prevention Trials Network 083 trial design. Abbreviations: CAB, cabotegravir; CAB-LA, long-acting cabotegravir; PK, pharmacokinetic; TDF/FTC, tenofovir disoproxil fumarate/emtricitabine. Adapted from Landovitz et al.
Figure 2.
Figure 2.
Pharmacologic and virologic data for HIV breakthrough cases in the cabotegravir group from the HIV Prevention Trials Network 083 study. study. Bold mutations are major mutations in the International Antiviral Society-USA resistance guidelines. See text on page 4 for more context. Abbreviations: BLQ, below the limit of quantification; CAB-LA, long-acting cabotegravir; LLOQ, lower limit of quantitation; PA-IC90, protein-adjusted 90% inhibitory concentration; TDF/FTC, tenofovir disoproxil fumarate/emtricitabine. Adapted from Landovitz et al.
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References

    1. Coelho LE, Torres TS, Veloso VG, Landovitz RJ, Grinsztejn B. Pre-exposure prophylaxis 2.0: new drugs and technologies in the pipeline. Lancet HIV. 2019;6(11):e788–e799. - PubMed
    1. UNAIDS. UNAIDS global AIDS update 2020. https://www.unaids.org/sites/default/files/media_asset/2020_global-aids-.... Accessed on August 15, 2021.
    1. Grant RM, Lama JR, Anderson PL, et al. Pre-exposure chemoprophylaxis for HIV prevention in men who have sex with men. N Engl J Med. 2010;363(27):2587–2599. - PMC - PubMed
    1. Anderson PL, Glidden DV, Liu A, et al. Emtricitabine-tenofovir concentrations and pre-exposure prophylaxis efficacy in men who have sex with men. Sci Transl Med. 2012;4(151):151ra125. - PMC - PubMed
    1. Grant RM, Anderson PL, McMahan V, et al. Uptake of pre-exposure prophylaxis, sexual practices, and HIV incidence in men and transgender women who have sex with men: a cohort study. Lancet Infect Dis. 2014;14(9):820–829. - PMC - PubMed