SummaryBackgroundRandomised placebo-controlled trials have shown that daily oral pre-exposure prophylaxis (PrEP) with tenofovir–emtricitabine reduces the risk of HIV infection. However, this benefit could be counteracted by risk compensation in users of PrEP. We did the PROUD study to assess this effect.MethodsPROUD is an open-label randomised trial done at 13 sexual health clinics in England. We enrolled HIV-negative gay and other men who have sex with men who had had anal intercourse without a condom in the previous 90 days. Participants were randomly assigned (1:1) to receive daily combined tenofovir disoproxil fumarate (245 mg) and emtricitabine (200 mg) either immediately or after a deferral period of 1 year. Randomisation was done via web-based access to a central computer-generated list with variable block sizes (stratified by clinical site). Follow-up was quarterly. The primary outcomes for the pilot phase were time to accrue 500 participants and retention; secondary outcomes included incident HIV infection during the deferral period, safety, adherence, and risk compensation. The trial is registered with ISRCTN (number ISRCTN94465371) and ClinicalTrials.gov (NCT02065986).FindingsWe enrolled 544 participants (275 in the immediate group, 269 in the deferred group) between Nov 29, 2012, and April 30, 2014. Based on early evidence of effectiveness, the trial steering committee recommended on Oct 13, 2014, that all deferred participants be offered PrEP. Follow-up for HIV incidence was complete for 243 (94%) of 259 patient-years in the immediate group versus 222 (90%) of 245 patient-years in the deferred group. Three HIV infections occurred in the immediate group (1·2/100 person-years) versus 20 in the deferred group (9·0/100 person-years) despite 174 prescriptions of post-exposure prophylaxis in the deferred group (relative reduction 86%, 90% CI 64–96, p=0·0001; absolute difference 7·8/100 person-years, 90% CI 4·3–11·3). 13 men (90% CI 9–23) in a similar population would need access to 1 year of PrEP to avert one HIV infection. We recorded no serious adverse drug reactions; 28 adverse events, most commonly nausea, headache, and arthralgia, resulted in interruption of PrEp. We detected no difference in the occurrence of sexually transmitted infections, including rectal gonorrhoea and chlamydia, between groups, despite a suggestion of risk compensation among some PrEP recipients.InterpretationIn this high incidence population, daily tenofovir–emtricitabine conferred even higher protection against HIV than in placebo-controlled trials, refuting concerns that effectiveness would be less in a real-world setting. There was no evidence of an increase in other sexually transmitted infections. Our findings strongly support the addition of PrEP to the standard of prevention for men who have sex with men at risk of HIV infection.FundingMRC Clinical Trials Unit at UCL, Public Health England, and Gilead Sciences.

The EuroVacc 02 phase I trial has evaluated the safety and immunogenicity of a prime-boost regimen comprising recombinant DNA and the poxvirus vector NYVAC, both expressing a common immunogen consisting of Env, Gag, Pol, and Nef polypeptide domain from human immunodeficiency virus (HIV)-1 clade C isolate, CN54. 40 volunteers were randomized to receive DNA C or nothing on day 0 and at week 4, followed by NYVAC C at weeks 20 and 24. The primary immunogenicity endpoints were measured at weeks 26 and 28 by the quantification of T cell responses using the interferon γ enzyme-linked immunospot assay. Our results indicate that the DNA C plus NYVAC C vaccine regimen was highly immunogenic, as indicated by the detection of T cell responses in 90% of vaccinees and was superior to responses induced by NYVAC C alone (33% of responders). The vaccine-induced T cell responses were (a) vigorous in the case of the env response (mean 480 spot-forming units/106 mononuclear cells at weeks 26/28), (b) polyfunctional for both CD4 and CD8 T cell responses, (c) broad (the average number of epitopes was 4.2 per responder), and (d) durable (T cell responses were present in 70% of vaccinees at week 72). The vaccine-induced T cell responses were strongest and most frequently directed against Env (91% of vaccines), but smaller responses against Gag-Pol-Nef were also observed in 48% of vaccinees. These results support the development of the poxvirus platform in the HIV vaccine field and the further clinical development of the DNA C plus NYVAC C vaccine regimen.

SummaryBackgroundInnovative prevention strategies for HIV-1 transmission are urgently needed. PRO2000 vaginal gel was efficacious against HIV-1 transmission in studies in macaques; we aimed to assess efficacy and safety of 2% and 0·5% PRO2000 gels against vaginal HIV-1 transmission in women in sub-Saharan Africa.MethodsMicrobicides Development Programme 301 was a phase 3, randomised, double-blind, parallel-group trial, undertaken at 13 clinics in South Africa, Tanzania, Uganda, and Zambia. We randomly assigned sexually active women, aged 18 years or older (≥16 years in Tanzania and Uganda) without HIV-1 infection in a 1:1:1 ratio to 2% PRO2000, 0·5% PRO2000, or placebo gel groups for 52 weeks (up to 104 weeks in Uganda). Randomisation was done by computerised random number generator. Investigators and participants were masked to group assignment. The primary efficacy outcome was incidence of HIV-1 infection before week 52, which was censored for pregnancy and excluded participants without HIV-1 follow-up data or with HIV-1 infection at enrolment. HIV-1 status was established by rapid tests or ELISA at screening at 12 weeks, 24 weeks, 40 weeks, and 52 weeks, and confirmed in a central reference laboratory. The primary safety endpoint was an adverse event of grade 3 or worse. Use of 2% PRO2000 gel was discontinued on Feb 14, 2008, on the recommendation of the Independent Data Monitoring Committee because of low probability of benefit. This trial is registered at http://isrctn.org, number ISRCTN 64716212.FindingsWe enrolled 9385 of 15 818 women screened. 2591 (95%) of 2734 participants enrolled to the 2% PRO2000 group, 3156 (95%) of 3326 in the 0·5% PRO2000 group, and 3112 (94%) of 3325 in the placebo group were included in the primary efficacy analysis. Mean reported gel use at last sex act was 89% (95% CI 86–91). HIV-1 incidence was much the same between groups at study end (incidence per 100 woman-years was 4·5 [95% CI 3·8–5·4] for 0·5% PRO2000 vs 4·3 [3·6–5·2] for placebo, hazard ratio 1·05 [0·82–1·34], p=0·71), and at discontinuation (4·7 [3·8–5·8] for 2% PRO2000 gel, 3·9 [3·0–4·9] for 0·5% PRO2000 gel, and 3·9 [3·1–5·0] for placebo gel). Incidence of the primary safety endpoint at study end was 4·6 per 100 woman-years (95% CI 3·9–5·4) in the 0·5% PRO2000 group and 3·9 (3·2–4·6) in the placebo group; and was 4·5 (3·7–5·5) in the 2% PRO2000 group at discontinuation.InterpretationAlthough safe, 0·5% PRO2000 and 2% PRO2000 are not efficacious against vaginal HIV-1 transmission and are not indicated for this use.FundingUK Department for International Development, UK Medical Research Council, European and Developing Countries Clinical Trials Partnership, International Partnership for Microbicides, and Endo Pharmaceuticals Solutions.

In a meta-analysis of individual participant data, Charles Morrison and colleagues explore the association between hormonal contraception use and risk of HIV infection in sub-Saharan Africa.