Effectiveness of vaginal microbicides in preventing HIV transmission

Abstract

ObjectiveTo evaluate the evidence on the effectiveness of vaginal microbicides in preventing HIV transmission in women.MethodsSystematic review through a comprehensive search of relevant electronic databases for eligible randomised controlled trials (RCTs) published through June 2019. Two authors independently screened titles and abstracts according to eligibility criteria, then extracted data and assessed risk of bias of included studies. We conducted a random‐effects meta‐analysis of risk ratios (RR) of HIV infection and assessed heterogeneity using chi‐squared and I2 tests. Sources of heterogeneity were investigated through subgroup analysis, publication bias was assessed using funnel plots, and certainty of evidence was graded using GRADEPro software.ResultsWe included 18 RCTs which enrolled 40,048 sexually active, HIV‐negative, non‐pregnant women, aged 16 years and older, mainly from sub‐Saharan Africa. The intravaginal ring containing dapivirine significantly reduced HIV risk by 29% (RR 0.71, 95% CI: 0.57–0.89; 2 RCTs, 4,564 women, moderate certainty of evidence). Estimates of effect of tenofovir 1% (RR 0.83, 95% CI: 0.65–1.06), nonoxynol‐9 (RR 1.15, 95% CI: 0.93–1.42), cellulose sulphate (RR 1.16, 95% CI: 0.61–2.21), SAVVY (RR 1.34, 95% CI: 0.69–2.59), Carraguard (RR 0.89, 95% CI: 0.71–1.10), BufferGel (RR 1.02, 95% CI: 0.71–1.46), 0.5% PRO2000 (RR 0.88, 95% CI: 0.60–1.28) and 2% PRO2000 (RR 0.81, 95% CI: 0.58–1.12) failed to reach statistical significance; each had low certainty of evidence.ConclusionThe long‐acting intravaginal ring containing dapivirine significantly reduced risk of HIV transmission in women by 29%. The remaining microbicides had no evident effect.

Baseline and time‐updated factors in preclinical development of anionic dendrimers as successful anti‐HIV‐1 vaginal microbicides

“…Several antiretroviral drugs are currently in advanced stages of development as microbicides, either vaginally or rectally (Al‐Khouja et al, 2020; Bunge et al, 2020; A. Y. Liu et al, 2019; MTN, 2020; Pleasants et al, 2020). However, there is no commercially available microbicide due to the lack of effectiveness of these products in preclinical and clinical trials for many reasons (Baeten et al, 2020; Musekiwa et al, 2020; Notario‐Perez et al, 2017).…”

Long-acting antiretrovirals: a new era for the management and prevention of HIV infection

“…According to a systematic review of two Phase III trials (RING study 98 and ASPIRE study 99 ), a beneficial 29% reduction in HIV risk has been demonstrated with the intravaginal dapivirine ring (relative risk of 0.71; 95% CI 0.57–0.89). 100 Despite appearing to be less effective than oral PrEP, the vaginal ring represents an alternative for women who are unable to take oral PrEP according to the recommendations. Moreover, current developments are underway to include both contraception and HIV prevention in a single intravaginal ring.…”

From Bulk to Nanoparticles: An Overview of Antiviral Materials, Its Mechanisms, and Applications

“…[ 104 ] However, PRO 2000 showed no evidence of efficacy against HIV in a clinical trial. [ 260 ] In vitro trials are not sufficient to indicate the antiviral activity of such materials in mammalian systems. Nonetheless, based on these observations, these materials can still be used for other applications like coatings, considering their direct interaction with the virus.…”