A Mechanistic In Vivo/Ex Vivo Pharmacokinetic-Pharmacodynamic Model of Tenofovir for HIV Prevention.

Defining tissue and plasma-specific prophylactic drug concentrations is central to pre-exposure prophylaxis product development for sexual transmission of HIV-1. Pharmacokinetic (PK) data from study RMP-02/MTN-006 comparing single dose oral tenofovir disoproxil fumarate with single and multiple dose rectal tenofovir (TFV) gel administration in HIV-1 seronegative adults was used to construct a multicompartment plasma-rectal tissue population PK model for TFV and tenofovir-diphosphate (TFVdp) in plasma and rectal tissue. PK data were collected in five matrices: TFV (plasma, rectal tissue homogenate), TFVdp (peripheral blood mononuclear cells, rectal mononuclear cells (MMCs), rectal tissue homogenate). A viral growth compartment and a delayed effect compartment for p24 antigen expression measured from an ex vivo explant assay described HIV-1 infection and replication. Using a linear PK/pharmacodynamic model, MMC TFVdp levels over 9,000 fmol/million cells in the explant assay provided apparent viral replication suppression down to 1%. Parameters were estimated using NONMEM version 7.4.

HIV seronegativity in children, adolescents and young adults living with perinatally acquired HIV: A cross-sectional study in Thailand.

INTRODUCTION: Early initiation of combination antiretroviral therapy (ART) with long-term viral suppression may lead to seronegativity in grown-up children with perinatally acquired HIV (PHIV). This study aimed to determine the frequency and associated factors of seronegativity in Thai children, adolescents and young adults with PHIV. METHODS: A cross-sectional HIV serological study was performed in children, adolescents and young adults two years or older who were receiving ART with undetectable HIV-RNA for at least one year from August 2018 to August 2019. Medical records were extracted for multivariate analysis of independent factors for seronegativity. RESULTS AND DISCUSSION: Of 110 patients, 50 male, median (range) age was 18.4 (4.8 to 26.6) years, 8 (7.3%) were seronegative, and 1 (0.9 %) was inconclusive. The seronegative group had a younger median (range) age at ART initiation: 3.0 (1.0 to 12.0) versus 40.0 (2.0 to 207.0) months, p = 0.045; and shorter median (range) duration from ART initiation to viral suppression: 16.8 (7.2 to 42.0) versus 55.2 (6.0 to 214.8) months, p = 0.036. Multivariate analysis identified younger age at ART initiation (aOR 0.69, 95% CI 0.49 to 0.98, p = 0.038) and shorter time to viral suppression after ART initiation (aOR 0.94, 95% CI 0.89 to 0.99, p = 0.019) as independent factors associated with HIV seronegativity. Of the infants who initiated ART < 3 and between three and six months of age, 50% and 26.7% became seronegative respectively. CONCLUSIONS: HIV seronegativity was observed in children and adolescents with PHIV who initiated ART early in infancy and had rapid and sustained virological response. Awareness of this phenomenon will help avoid inappropriate treatment interruption on the basis of negative antibody testing.

Stages of Adoption of "Treatment as Prevention" Among HIV-Negative Men Who Have Sex with Men Who Engage in Exchange Sex.

Prior research found low acceptability of HIV treatment as prevention (TasP; or Undetectable = Untransmittable) among HIV-negative men who have sex with men (MSM). This study reports on qualitative data regarding TasP adoption in a sample of 170 self-reported HIV-negative MSM who had engaged in exchange sex (received money, drugs, or other things in exchange for sex). We classified participants along five stages of TasP adoption: 1-unaware of TasP (11.2%); 2-aware, but perceived ineffective (17.1%); 3-perceived effective, but unwilling to use (35.3%); 4-willing to rely on TasP, but had never done so (24.1%); and 5-had relied on TasP (12.4%). Obstacles to TasP adoption included the following: not believing that it could completely prevent HIV transmission; deeply ingrained fears of HIV/AIDS; concerns about viral load fluctuation; and reluctance to trust a partner's claimed undetectable status. TasP promotion efforts, which can decrease barriers to HIV testing and HIV stigma, will be more effective if tailored to the obstacles specific to each stage of TasP adoption.

Sexual Behavior and Perceived HIV Risk Among HIV-Negative Members of Serodiscordant Couples in East Africa.

HIV risk perception may influence the use of HIV prevention interventions. Using data from HIV-negative adults enrolled in a study of pre-exposure prophylaxis (PrEP) and antiretroviral therapy for HIV-serodiscordant couples in Kenya and Uganda, we examined associations between: (1) condom use and risk perception and (2) risk perception and PrEP adherence. Two-thirds of HIV-negative partners reported condomless sex with their HIV-positive partner or another partner in the month prior to study enrollment. Compared to those who reported no condomless sex, participants who reported condomless sex during the month prior to study visit had fivefold higher odds of reporting "high risk" vs "no risk" perception (36.3 versus 10.9%: aOR 4.9, 95% CI 3.4-6.9). Reporting condomless sex in the most recent sex act was associated with increased odds of perceiving some HIV risk (aOR for high risk = 7.3, 95% CI 4.9-10.8; aOR for moderate risk = 4.8, 95% CI 3.5-6.7; aOR for low risk = 3.5, 95% CI 2.7-4.6). We found no significant association between risk perception and PrEP adherence. Sexual behavior aligned with perceived HIV risk, which can facilitate an HIV-negative individual's decisions about PrEP use.

Birth Prevalence of Congenital Cytomegalovirus Infection in HIV-Exposed Uninfected Children in the Era of Combination Antiretroviral Therapy.

OBJECTIVES: To estimate birth prevalence of congenital cytomegalovirus (cCMV) in HIV-exposed uninfected children born in the current era of combination antiretroviral therapy and describe cCMV-related neurodevelopmental and hearing outcomes. STUDY DESIGN: The Surveillance Monitoring for ART Toxicities cohort study follows HIV-exposed uninfected children at 22 sites in the US and Puerto Rico. Birth cCMV prevalence was estimated in a subset of participants who had blood pellets collected within three weeks of birth and underwent ≥1 of 6 assessments evaluating cognitive and language development including an audiologic examination between 1 and 5 years of age. Detection of CMV DNA by polymerase chain reaction testing of peripheral blood mononuclear cells was used to diagnose cCMV. Proportions of suboptimal assessment scores were compared by cCMV status using Fisher exact test. RESULTS: Mothers of 895 eligible HIV-exposed uninfected children delivered between 2007 and 2015. Most (90%) were on combination antiretroviral therapy, 88% had an HIV viral load of ≤400 copies/mL, and 93% had CD4 cell counts of ≥200 cells/µL. Eight infants were diagnosed with cCMV, yielding an estimated prevalence of 0.89% (95% CI, 0.39%-1.75%). After adjusting for a sensitivity of 70%-75% for the testing method, projected prevalence was 1.2%-1.3%. No differences were observed in cognitive, language and hearing assessments by cCMV status. CONCLUSIONS: Although birth cCMV prevalence in HIV-exposed uninfected children born to women with well-controlled HIV is trending down compared with earlier combination antiretroviral therapy-era estimates, it is above the 0.4% reported for the general US population. HIV-exposed uninfected children remain at increased risk for cCMV.

S100A14 Is Increased in Activated NK Cells and Plasma of HIV-Exposed Seronegative People Who Inject Drugs and Promotes Monocyte-NK Crosstalk.

BACKGROUND: HIV-exposed seronegative people who inject drugs (HESN-PWID) have been shown to have increased natural killer (NK) cell and myeloid activation when compared with control donors. METHODS: We investigated potential mechanisms maintaining NK activation by conducting quantitative proteome comparisons of NK cells from HESN-PWID subjects and control donors. Proteins upregulated in NK cells were measured in the plasma of HESN-PWID subjects by ELISA and further investigated for their ability to induce innate immune activation in vitro. RESULTS: The NK cell proteome comparison showed markedly higher levels of interferon-stimulated proteins and S100 proteins, including S100A14. Consistent with these results, we observed significantly higher levels of S100A14 in the plasma of HESN-PWID subjects compared with controls (P = 0.033, n = 25). In vitro, the addition of recombinant S100A14 protein significantly activated NK cells in a peripheral blood mononuclear cell mixture (P = 0.011, n = 9), but not purified NK cells alone. Treatment of purified monocytes with recombinant S100A14 protein induced secretion of TNF-alpha and led to significantly higher NK CD69 activation (P = 0.0156, n = 7) in a co-culture through a TLR4-dependent interaction. CONCLUSIONS: Our study identified S100A14 as a novel protein increased within NK cells and plasma of HESN-PWID subjects with the capacity to sustain NK activation through TLR4-dependent activation of myeloid cells.

Brief Report: Medication Sharing Is Rare Among African HIV-1 Serodiscordant Couples Enrolled in an Efficacy Trial of Oral Pre-exposure Prophylaxis (PrEP) for HIV-1 Prevention.

Sharing of pre-exposure prophylaxis (PrEP) medications is a concern for PrEP implementation. For HIV-1 serodiscordant couples, sharing may undermine the HIV-1 prevention benefit and also cause antiretroviral resistance if taken by HIV-1 infected partners. Within a PrEP efficacy trial among HIV-1 serodiscordant couples, we assessed the occurrence of PrEP sharing by self-report and plasma tenofovir concentrations in HIV-1 infected partners. PrEP sharing was self-reported at <0.01% of visits, and 0%-1.6% of randomly selected and 0% of purposively selected specimens from HIV-1 infected participants had detectable tenofovir concentrations (median: 66.5 ng/mL, range: 1.3-292 ng/mL). PrEP sharing within HIV-1 serodiscordant couples was extremely rare.

Factors which influence treatment initiation for pulmonary non-tuberculous mycobacterium infection in HIV negative patients; a multicentre observational study.

BACKGROUND: Clinical, radiological and microbiological criteria inform diagnosis of pulmonary Non-Tuberculous Mycobacteria (NTM) disease and treatment decisions. This multicentre, review aims to characterise NTM disease meeting ATS/IDSA criteria and define factors associated with initiation of treatment. METHODS: Sputum samples growing NTM from 5 London hospitals between 2010 and 2014 were identified. Data for HIV-negative individuals meeting ATS/IDSA guidelines for pulmonary NTM disease were extracted. Associations between clinical variables and treatment decision were investigated using Chi-squared, Fishers-exact or Mann Whitney tests. Factors associated with treatment in univariate analysis (p < 0.150) were included in a multivariate logistic regression model. RESULTS: NTM were identified from 817 individuals' sputum samples. 108 met ATS/IDSA criteria. 42/108 (39%) were initiated on treatment. Median age was 68 (56-78) in the cohort. On multivariate analysis, factors significantly associated with treatment of pulmonary NTM infection were: Cavitation on HRCT (OR: 6.49; 95% CI: 2.36-17.81), presenting with night sweats (OR 4.18; 95% CI: 1.08-16.13), and presenting with weight loss (OR 3.02; 95% CI: 1.15-7.93). Of those treated, 18(43%) have completed treatment, 9(21%) remain on treatment, 10(24%) stopped due to side effects, 5(12%) died during treatment. Mortality was 31% (n = 13) in treated versus 21% (n = 14) in the non-treated cohort. Subgroup analysis of individual NTM species did not observe any differences in treatment initiation or outcomes between groups. DISCUSSION: Decision to treat pulmonary NTM infection requires clinical judgement when interpreting clinical guidelines. Factors independently associated with decision to treat in this HIV-negative cohort include cavitation on HRCT and presenting with night sweats or weight loss.

Changes in Vaginal Microbiota and Immune Mediators in HIV-1-Seronegative Kenyan Women Initiating Depot Medroxyprogesterone Acetate.

BACKGROUND: Depot medroxyprogesterone acetate (DMPA) is associated with HIV acquisition. We studied changes in vaginal microbiota and inflammatory milieu after DMPA initiation. METHODS: In a cohort of HIV-negative Kenyan women, we collected monthly vaginal swabs over 1 year before and after DMPA. Using quantitative polymerase chain reaction, we compared quantities of Lactobacillus crispatus, Lactobacillus jensenii, Lactobacillus iners, Gardnerella vaginalis, and total bacterial load (16S ribosomal RNA gene levels). Six vaginal immune mediators were measured with enzyme-linked immunosorbent assay. Trends in the detection and quantity of bacteria were estimated by logistic and linear mixed-effects regression. RESULTS: From 2010 to 2012, 15 HIV-seronegative women initiated DMPA, contributing 85 visits (median, 6 visits/woman; range, 3-8 visits/woman). The median time of DMPA-exposed follow-up was 8.4 months (range, 1.5-11.6 months). Seven women (46%) had bacterial vaginosis within 70 days before DMPA start. L. iners was detected in 13 women (87%) before DMPA start, but other lactobacilli were rarely detected. Gardnerella vaginalis decreased by 0.21 log10 copies per swab per month after DMPA exposure (P = 0.01). Total bacterial load decreased by 0.08 log10 copies per swab per month of DMPA (P = 0.02). Sustained decreases in interleukin (IL)-6 (P = 0.03), IL-8 (P = 0.04), and IL-1 receptor antagonist (P < 0.001) were also noted. Nine women (60%) had L. crispatus detected post-DMPA, which significantly correlated with reduced IL-6 (P < 0.01) and IL-8 (P = 0.02). CONCLUSIONS: Initiation of DMPA led to sustained shifts in vaginal bacterial concentrations and levels of inflammatory mediators. Further studies are warranted to outline components of the vaginal microbiota influenced by DMPA use and impact on HIV susceptibility.

Reactivity of routine HIV antibody tests in children who initiated antiretroviral therapy in early infancy as part of the Children with HIV Early Antiretroviral Therapy (CHER) trial: a retrospective analysis.

BACKGROUND: Early antiretroviral therapy (ART) and virological suppression can affect evolving antibody responses to HIV infection. We aimed to assess frequency and predictors of seronegativity in infants starting early ART. METHODS: We compared HIV antibody results between two of three treatment groups of the Children with HIV Early Antiretroviral Therapy (CHER) trial, done from July, 2005, until July, 2011, in which infants with HIV infection aged 5·7-12·0 weeks with a percentage of CD4-positive T lymphocytes of at least 25% were randomly assigned to immediate ART for 96 weeks (ART-96W) or deferred ART until clinical or immunological progression (ART-Def). We measured antibody from all available stored samples for ART-96W and ART-Def at trial week 84 using three assays: fourth-generation enzyme immunoassay HIV antigen-antibody combination, HIV-1 and HIV-2 rapid antibody test, and quantitative anti-gp120 IgG ELISA. We also assessed odds of seropositivity with respect to age of ART initiation and cumulative viral load. The CHER trial was registered with ClinicalTrials.gov, number NCT00102960. FINDINGS: The median age of the infants from when samples were taken (184 samples from 268 infants) was 92 weeks (IQR 90·6-93·4). More specimens from the ART-96W group were seronegative than from the ART-Def group by enzyme immunoassay (ART-96W 49 [46%] of 107 vs ART-Def eight [11%] of 75; p<0·0001) and rapid antibody test (54 [53%] of 101 vs eight [11%] of 74; p<0·0001). Median anti-gp120 IgG concentration was lower in the ART-96W group (230 µg/µL [IQR 133-13 129]) than in the ART-Def group (6870 µg/µL [1706-53 645]; p<0·0001). If ART was started between 12 and 24 weeks of age, odds of seropositivity were increased 13·7 times (95% CI 3·1-60·2; p=0·001) compared with starting it between 0 and 12 weeks. All children starting ART aged older than 24 weeks were seropositive. Cumulative viral load to week 84 correlated with anti-gp120 IgG concentrations (coefficient 0·54; p<0·0001) and increased odds of seropositivity (odds ratio 1·59 [95% CI 1·1-2·3]) adjusted for ART initiation age. INTERPRETATION: About half of children starting ART before 12 weeks of age were HIV seronegative by almost 2 years of age. HIV antibody tests cannot be used to reconfirm HIV diagnosis in children starting early ART. Long-term effects of seronegativity need further study. Clear guidelines are needed for retesting alongside improved diagnostic tests. FUNDING: Wellcome Trust, Medical Research Council, and National Institutes of Health.

Turning the tide against AIDS by preventing new HIV infections initial experience with Minnesota's first PrEP clinic.

During the last 30 years, there have been remarkable improvements in the treatment of patients with HIV. New drug regimens are both tolerable and easy to take, resulting in HIV viral suppression and markedly improved clinical outcomes. Viral suppression in patients with HIV significantly decreases the chance they will transmit the virus. Yet HIV transmission levels in the United States remain unacceptably high. Prevention efforts focused on HIV-negative persons who are at high risk for infection have led to the development of a pre-exposure prophylaxis (PrEP) strategy. This article provides an overview of PrEP and a review of the evidence for it, barriers to its use and how PrEP is being used in the United States and Minnesota. With concerted efforts by physicians, patients and public health authorities, PrEP could become a major tool in preventing transmission of the HIV virus.

Pre-exposure prophylaxis for conception (PrEP-C) as a risk reduction strategy in HIV-positive men and HIV-negative women in the UK.

Couples wishing to have biological children when one partner is HIV positive and the other is HIV negative present clinicians with complex clinical, social and ethical considerations. We established two multidisciplinary pre-conception services for HIV-positive individuals and their partners. We report the first UK use of pre-exposure prophylaxis for conception (PrEP-C) as part of an overall risk reduction strategy. Couples were counselled and written informed consent for PrEP-C was obtained. Patient demographics, HIV and medical histories were recorded. Males underwent baseline semen analysis and seminal HIV viral load testing. Females had full fertility screens. Both partners were screened for sexually transmitted infections. All couples used timed ovulatory intercourse (TOI). Tenofovir±emtricitabine was taken by the female at protocol designated times before±after TOI. Thirty-two male positive/female negative couples used the services. Thirteen couples have used PrEP-C (median age of male 41 years (range 32-56), female 31 (28-43); median CD4 533 (236-1194); all male plasma and seminal HIV viral loads were undetectable). Eleven pregnancies in 10 couples have resulted in 7 live births, 1 ongoing pregnancy and 4 miscarriages (5/40, 6/40, 10/40 and 1 twin 17/40) after a median of 2.5 attempts (range 1-5). PrEP-C was well tolerated with no discontinuations and no HIV transmissions. These data suggest that PrEP-C is a safe and effective option for serodiscordant couples wishing to conceive; a standardised protocol has been developed; data collection via a central database is under way.

Antiretroviral therapy to prevent HIV transmission in serodiscordant couples in China (2003-11): a national observational cohort study.

BACKGROUND: On the basis of the results of the randomised clinical trial HPTN 052 and observational studies, WHO has recommended that antiretroviral therapy be offered to all HIV-infected individuals with uninfected partners of the opposite sex (serodiscordant couples) to reduce the risk of transmission. Whether or not such a public health approach is feasible and the outcomes are sustainable at a large scale and in a developing country setting has not previously been assessed. METHODS: In this retrospective observational cohort study, we included treated and treatment-naive HIV-positive individuals with HIV-negative partners of the opposite sex who had been added to the national HIV epidemiology and treatment databases between Jan 1, 2003 and Dec 31, 2011. We analysed the annual rate of HIV infection in HIV-negative partners during follow-up, stratified by treatment status of the index partner. Cox proportional hazards analyses were done to examine factors related to HIV transmission. FINDINGS: Based on data from 38,862 serodiscordant couples, with 101,295·1 person-years of follow-up for the seronegative partners, rates of HIV infection were 2·6 per 100 person-years (95% CI 2·4-2·8) among the 14,805 couples in the treatment-naive cohort (median baseline CD4 count for HIV-positive partners 441 cells per µl [IQR 314-590]) and 1·3 per 100 person-years (1·2-1·3) among the 24,057 couples in the treated cohort (median baseline CD4 count for HIV-positive partners 168 cells per µl [62-269]). We calculated a 26% relative reduction in HIV transmission (adjusted hazard ratio 0·74, 95% CI 0·65-0·84) in the treated cohort. The reduction in transmission was seen across almost all demographic subgroups and was significant in the first year (0·64, 0·54-0·76), and among couples in which the HIV-positive partner had been infected by blood or plasma transfusion (0·76, 0·59-0·99) or heterosexual intercourse (0·69, 0·56-0·84), but not among couples in which the HIV-positive partner was infected by injecting drugs (0·98, 0·71-1·36). INTERPRETATION: Antiretroviral therapy for HIV-positive individuals in serodiscordant couples reduced HIV transmission across China, which suggests that the treatment-as-prevention approach is a feasible public health prevention strategy on a national scale in a developing country context. The durability and generalisability of such protection, however, needs to be further studied. FUNDING: Chinese Government's 12th Five-Year Plan, the National Natural Science Foundation of China, and the Canadian International Development Research Centre.

Population-level impact of hormonal contraception on incidence of HIV infection and pregnancy in women in Durban, South Africa.

OBJECTIVE: To estimate the potential impact of using hormonal contraceptives on rates of infection with human immunodeficiency virus type 1 (HIV-1) and pregnancy by theoretically removing the use of hormonal contraceptives from a study population. METHODS: A prospective cohort study included 3704 HIV-negative women who were enrolled in two biomedical trials that tested two vaginal microbicides (PRO 2000 and Carraguard®) for the prevention of HIV-1 in Durban, South Africa, in 2004-2009. Cox proportional hazards regression models along with partial population attributable risks (PARs) and their 95% confidence intervals (CIs) were calculated to assess the relative population-level impact of the use of hormonal contraceptives on HIV-1 seroconversion rates and on pregnancy rates. FINDINGS: Women who reported using hormonal contraceptives at enrolment in the trial had a higher risk of HIV-1 seroconversion (adjusted hazards ratio: 1.24; 95% CI: 0.97-1.58) than women who reported using other types of contraceptives at enrolment. At the population level, the use of hormonal contraceptives (pills or injectables) at baseline and during study follow-up accounted for approximately 20% (95% CI: 16-22) of HIV-1 seroconversions. However, the partial PAR indicated a relative impact of 12% (95% CI: 9.0-15.7). On the other hand, 72% (95% CI: 66-77) of the pregnancies could have been avoided if all women had used hormonal contraceptives. CONCLUSION: Women using hormonal contraceptives need comprehensive counselling on simultaneous prevention of HIV-1 infection.

Nonreproducibility of "snap-frozen" rectal biopsies for later use in ex vivo explant infectibility studies.

Sexual transmission accounts for the majority of new HIV infections worldwide with sexually exposed cervicovaginal and colorectal mucosae being primary sites of infection. Two recent Phase 1 rectal microbicide trials included, as an ancillary endpoint, suppression of ex vivo HIV infection of in vivo microbicide-exposed rectal mucosal tissue biopsies. Both trials demonstrated significant suppression of biopsy infectibility in drug-exposed versus placebo-exposed tissue. This potential early biomarker of efficacy has raised the feasibility of utilizing "snap-frozen" tissue samples, acquired at multiple trial sites to be shipped for central processing, providing a mechanism to correlate tissue drug concentrations with a functional index of HIV prevention. While previous reports have indicated acceptable comparability of fresh versus freeze-thawed cervicovaginal tissue samples, no similar evaluations with colorectal tissue biopsies have been done. In this study, rectal biopsies from healthy, HIV-seronegative participants were assessed for structural integrity (histology), viability (MTT assays), and tissue infectibility to compare results from fresh versus combinations of freeze/thaw protocols. Results indicated that while all protocols showed equivalent viability with fresh samples (MTT), histology documented poor preservation of tissue integrity following freezing. Infectibility results from freeze-thawed colorectal tissue were markedly lower (usually<25% of fresh samples) and varied greatly and unpredictably. Centralized colorectal tissue infectibility assays using biopsies from remote trial sites cannot currently be supported under these protocols.

Characteristics of HIV-1 serodiscordant couples enrolled in a clinical trial of antiretroviral pre-exposure prophylaxis for HIV-1 prevention.

INTRODUCTION: Stable heterosexual HIV-1 serodiscordant couples in Africa have high HIV-1 transmission rates and are a critical population for evaluation of new HIV-1 prevention strategies. The Partners PrEP Study is a randomized, double-blind, placebo-controlled trial of tenofovir and emtricitabine-tenofovir pre-exposure prophylaxis to decrease HIV-1 acquisition within heterosexual HIV-1 serodiscordant couples. We describe the trial design and characteristics of the study cohort. METHODS: HIV-1 serodiscordant couples, in which the HIV-1 infected partner did not meet national guidelines for initiation of antiretroviral therapy, were enrolled at 9 research sites in Kenya and Uganda. The HIV-1 susceptible partner was randomized to daily oral tenofovir, emtricitabine-tenofovir, or matching placebo with monthly follow-up for 24-36 months. RESULTS: From July 2008 to November 2010, 7920 HIV-1 serodiscordant couples were screened and 4758 enrolled. For 62% (2966/4758) of enrolled couples, the HIV-1 susceptible partner was male. Median age was 33 years for HIV-1 susceptible and HIV-1 infected partners [IQR (28-40) and (26-39) respectively]. Most couples (98%) were married, with a median duration of partnership of 7.0 years (IQR 3.0-14.0) and recent knowledge of their serodiscordant status [median 0.4 years (IQR 0.1-2.0)]. During the month prior to enrollment, couples reported a median of 4 sex acts (IQR 2-8); 27% reported unprotected sex and 14% of male and 1% of female HIV-1 susceptible partners reported sex with outside partners. Among HIV-1 infected partners, the median plasma HIV-1 level was 3.94 log(10) copies/mL (IQR 3.31-4.53) and median CD4 count was 496 cells/µL (IQR 375-662); the majority (64%) had WHO stage 1 HIV-1 disease. CONCLUSIONS: Couples at high risk of HIV-1 transmission were rapidly recruited into the Partners PrEP Study, the largest efficacy trial of oral PrEP. (ClinicalTrials.gov NCT00557245).

Bone mineral density in HIV-negative men participating in a tenofovir pre-exposure prophylaxis randomized clinical trial in San Francisco.

BACKGROUND: Pre-exposure prophylaxis (PrEP) trials are evaluating regimens containing tenofovir-disoproxil fumarate (TDF) for HIV prevention. We determined the baseline prevalence of low bone mineral density (BMD) and the effect of TDF on BMD in men who have sex with men (MSM) in a PrEP trial in San Francisco. METHODS/FINDINGS: We evaluated 1) the prevalence of low BMD using Dual Energy X-ray Absorptiometry (DEXA) in a baseline cohort of 210 HIV-uninfected MSM who screened for a randomized clinical trial of daily TDF vs. placebo, and 2) the effects of TDF on BMD in a longitudinal cohort of 184 enrolled men. Half began study drug after a 9-month delay to evaluate changes in risk behavior associated with pill-use. At baseline, 20 participants (10%) had low BMD (Z score≤-2.0 at the L2-L4 spine, total hip, or femoral neck). Low BMD was associated with amphetamine (OR = 5.86, 95% CI 1.70-20.20) and inhalant (OR = 4.57, 95% CI 1.32-15.81) use; men taking multivitamins, calcium, or vitamin D were less likely to have low BMD at baseline (OR = 0.26, 95% CI 0.10-0.71). In the longitudinal analysis, there was a 1.1% net decrease in mean BMD in the TDF vs. the pre-treatment/placebo group at the femoral neck (95% CI 0.4-1.9%), 0.8% net decline at the total hip (95% CI 0.3-1.3%), and 0.7% at the L2-L4 spine (95% CI -0.1-1.5%). At 24 months, 13% vs. 6% of participants experienced >5% BMD loss at the femoral neck in the TDF vs. placebo groups (p = 0.13). CONCLUSIONS: Ten percent of HIV-negative MSM had low BMD at baseline. TDF use resulted in a small but statistically significant decline in BMD at the total hip and femoral neck. Larger studies with longer follow-up are needed to determine the trajectory of BMD changes and any association with clinical fractures. TRIAL REGISTRATION: ClinicalTrials.gov: NCT00131677.