Preexposure prophylaxis is efficacious for HIV-1 prevention among women using depot medroxyprogesterone acetate for contraception

Establishing adherence-concentration-efficacy thresholds of TDF-FTC pre-exposure prophylaxis for HIV prevention in African women: a protocol for the Women TDF-FTC Benchmark Study

Background

Oral pre-exposure prophylaxis (PrEP) using co-formulated emtricitabine (FTC) and tenofovir disoproxil fumarate (TDF) is a potent HIV prevention method for men and women, with its efficacy highly dependent on adherence. A pivotal HIV efficacy study combined with a directly observed pharmacological study defined the thresholds for HIV protection in men who have sex with men (MSM), which are the keys to PrEP promotion and development of new PrEP agents. For African women at risk for HIV and belonging to a priority group considered due to disproportionately high incident HIV infections, the variable adherence in PrEP clinical trials and the limited pharmacologic data have resulted in a lack of clarity about the PrEP adherence required for HIV protection. We propose a study to quantify the adherence-concentration-efficacy thresholds of TDF/FTC PrEP among African cisgender women to inform decisions about optimal PrEP dosing and adherence for HIV protection.

Methods

We randomized 45 low-risk HIV-uninfected African women, aged 18-30 years old, to directly observe the TDF/FTC PrEP of two, four, or seven doses per week for 8 weeks. A complementary age-matched pregnant women cohort at high risk of HIV, who will receive seven doses per week, was recruited (N = 15) with the primary aim of establishing benchmark concentrations in dried blood spots and peripheral blood mononuclear cells. Plasma, whole blood (WB), urine, hair, vaginal fluid, and vaginal tissue (non-pregnant women only) were archived for future testing. Drug concentrations were measured using methods validated for each biological matrix. Pharmacokinetic models were fitted to drug concentrations to quantify concentration-adherence thresholds. To define the drug concentrations associated with HIV protection, we applied the newly defined thresholds from the primary pharmacologic trial to the subset of women randomized to TDF/FTC or TDF in the Partners PrEP Study with the drug concentration assessed in plasma and WB samples. Multiple imputation was used to construct a data set with drug concentrations at each visit when an HIV test was performed for the entire cohort, replicating the work for MSM.

Discussion

The proposed study generated the first African women-specific TDF-PrEP adherence-concentration-efficacy thresholds essential for guiding the accurate interpretation of TDF/FTC PrEP programs and clinical trials of novel HIV prevention products using TDF/FTC as an active control.

Clinical Trial Registration

ClinicalTrials.gov, identifier (NCT05057858).

Preexposure Prophylaxis for the Prevention of HIV: Updated Evidence Report and Systematic Review for the US Preventive Services Task Force

Importance

A 2019 review for the US Preventive Services Task Force (USPSTF) found oral preexposure prophylaxis (PrEP) associated with decreased HIV infection risk vs placebo or no PrEP in adults at increased HIV acquisition risk. Newer PrEP regimens are available.

Objective

To update the 2019 review on PrEP, to inform the USPSTF.

Data Sources

Ovid MEDLINE, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, and Embase (January 2018 to May 16, 2022); surveillance through March 24, 2023.

Study Selection

Randomized clinical trials of PrEP vs placebo or no PrEP or newer vs older PrEP regimens and diagnostic accuracy studies of instruments for predicting incident HIV infection.

Data Extraction and Synthesis

Dual review of titles and abstracts, full-text articles, study quality, and data abstraction. Data were pooled using the DerSimonian and Laird random-effects model.

Main Outcomes and Measures

HIV acquisition, mortality, and harms; and diagnostic test accuracy.

Results

Thirty-two studies were included in the review (20 randomized clinical trials [N = 36 543] and 12 studies of diagnostic accuracy [N = 5 544 500]). Eleven trials in the 2019 review found oral PrEP associated with decreased HIV infection risk vs placebo or no PrEP (n = 18 172; relative risk [RR], 0.46 [95% CI, 0.33-0.66]). Higher adherence was associated with greater efficacy. One new trial (n = 5335) found oral tenofovir alafenamide/emtricitabine (TAF/FTC) to be noninferior to tenofovir disoproxil fumarate/emtricitabine (TDF/FTC) in men who have sex with men (RR, 0.47 [95% CI, 0.19-1.14]). Two new trials found long-acting injectable cabotegravir associated with decreased risk of HIV infection vs oral TDF/FTC (RR, 0.33 [95% CI, 0.18-0.62] in cisgender men who have sex with men and transgender women [n = 4490] and RR, 0.11 [95% CI, 0.04-0.31] in cisgender women [n = 3178]). Discrimination of instruments for predicting incident HIV infection was moderate in men who have sex with men (5 studies; n = 25 488) and moderate to high in general populations of persons without HIV (2 studies; n = 5 477 291).

Conclusions and Relevance

In adults at increased HIV acquisition risk, oral PrEP was associated with decreased risk of acquiring HIV infection compared with placebo or no PrEP. Oral TAF/FTC was noninferior to oral TDF/FTC, and injectable cabotegravir reduced the risk of HIV infection compared with oral TDF/FTC in the populations studied.

PrEP awareness and use among reproductive age women in Miami, Florida

BACKGROUND

Miami, Florida is an epicenter of the HIV epidemic in the US, with 20% of new HIV infections occurring in women. Despite effectiveness of Pre-Exposure Prophylaxis (PrEP) in preventing HIV, only 10% of eligible women benefit from its use.

SETTING

This study evaluates PrEP awareness and use, and factors associated with PrEP awareness among sexually active women in Miami, Florida.

METHODS

Results reported in this study included cross-sectional data that were collected as part of a baseline visit from a parent study. Cis-gender, HIV-negative, 18-45-year-old, sexually active women were recruited as part of a study evaluating recurrent bacterial vaginosis and HIV risk. Participants completed questionnaires assessing socio-demographics, HIV risk factors, prior history of HIV testing and reproductive tract infections, PrEP awareness and use. Relationships between variables and PrEP awareness were analyzed and multivariable logistic regression identified variables strongly associated with PrEP awareness.

RESULTS

Among the 295 women enrolled, median age was 31 (24-38) years, 49% Black, 39% White, and 34% Hispanic. Of 63% who knew about PrEP, only 5% were on PrEP. Women with income below poverty line (OR = 2.00[1.04,3.87];p = 0.04), more male sexual partners in past month (OR = 1.30[1.01,1.68];p = 0.04), lifetime HIV testing (OR = 6.42[2.83,14.52];p<0.01), and current bacterial vaginosis (OR = 2.28[1.18,4.40];p = 0.01) were more likely to be aware of PrEP. Lower odds of PrEP awareness were associated with being Black (OR = 0.38[0.15,0.96];p = 0.04), Hispanic (OR = 0.18[0.08,0.39];p<0.01), heterosexual (OR = 0.29[0.11,0.77];p<0.01), and reporting inconsistent condom use during vaginal sex (OR = 0.21[0.08,0.56];p<0.01).

CONCLUSION

PrEP awareness is low among reproductive age women in a high-risk setting. Culturally tailored interventions are needed to increase PrEP awareness and uptake, especially among Black and Hispanic women with inconsistent condom use during vaginal sex with male partners.

Women for science and science for women: Gaps, challenges and opportunities towards optimizing pre-exposure prophylaxis for HIV-1 prevention

Preventing new HIV infections remains a global challenge. Young women continue to bear a disproportionate burden of infection. Oral pre-exposure prophylaxis (PrEP), offers a novel women-initiated prevention technology and PrEP trials completed to date underscore the importance of their inclusion early in trials evaluating new HIV PrEP technologies. Data from completed topical and systemic PrEP trials highlight the role of gender specific physiological and social factors that impact PrEP uptake, adherence and efficacy. Here we review the past and current developments of HIV-1 prevention options for women with special focus on PrEP considering the diverse factors that can impact PrEP efficacy. Furthermore, we highlight the importance of inclusion of female scientists, clinicians, and community advocates in scientific efforts to further improve HIV prevention strategies.

Characterizing the Impact of the COVID-19 Pandemic on HIV PrEP care: A Review and Synthesis of the Literature

The global COVID-19 pandemic and associated lockdown measures have caused disruptions to sexual health services and created additional barriers to the continuity of HIV pre-exposure prophylaxis (PrEP) among key populations. This review provides an examination of the influences of the pandemic on engagement in the PrEP care continuum. Using the PRISMA guideline, 46 studies were included in this review and the synthesis. Most of the studies were conducted in high-income settings through quantitative analysis. A majority of studies examining the changes in PrEP use suggested a decline or discontinuation in PrEP uptake during the pandemic. The most common reasons for stopping using PrEP were perceived barriers to PrEP-related care, having reduced sexual behaviors and fewer sexual partners, and reduced perceived risk of HIV infection. Limited studies documenting an increase in PrEP uptake were all in specific PrEP optimizing programs. During the pandemic, there is also an emerging trend of switching to on-demand PrEP from daily oral PrEP. Future studies should understand the mechanism of strategies that facilitated the improvements during the pandemic. PrEP implementation programs should consider alternative PrEP modalities and provide consistent and comprehensive knowledge about correct information.

Safety of oral tenofovir disoproxil - emtricitabine for HIV preexposure prophylaxis in adults

PURPOSE OF REVIEW

This review focuses on the safety of oral tenofovir disoproxil and emtricitabine (FTC) combination for HIV preexposure prophylaxis (PrEP) in adults.

RECENT FINDINGS

Gastrointestinal adverse events are common after treatment initiation but usually resolve within weeks. Although clinical trials did not report an increased risk of serious renal adverse events or tubulopathy, meta-analyses suggest that tenofovir disoproxil -FTC is associated with a slight but non-clinically relevant decline in estimated glomerular filtration rate (eGFR). A decline to less than 60 mL/min remains a rare event, which mainly occurs in users with an age >50 years or a baseline creatinine clearance < 90 mL/min. Similarly, a slight reduction in bone mineral density (BMD) was observed in clinical trials, but it did not result in an increased risk of bone fracture. BMD reduction and eGFR decline tend to resolve after treatment discontinuation. No drug interaction with contraception has been reported in women and no safety signal emerged in pregnant and breastfeeding women.

SUMMARY

Oral tenofovir disoproxil-FTC for HIV PrEP appears safe and well tolerated for most individuals. This supports demedicalization strategies aiming at increasing the number of PrEP users.

Integrating PrEP delivery in public health family planning clinics: a protocol for a pragmatic stepped wedge cluster randomized trial in Kenya

Background

Adolescent girls and young women account for a disproportionate fraction of new HIV infections in Africa and are a priority population for HIV prevention, including provision of pre-exposure prophylaxis (PrEP). Anchoring PrEP delivery to care settings like family planning (FP) services that women already access routinely may offer an efficient platform to reach HIV at-risk women. However, context-specific implementation science evaluation is needed.

Methods

The Family Planning Plus Project is a prospective, pragmatic implementation evaluation, designed as a stepped wedge, cluster randomized trial, at 12 clinics in Kenya. In collaboration with the Kenya Ministry of Health and Kisumu County Department of Health, we will introduce integration of HIV risk screening and PrEP delivery in public health FP clinics. The core multifaceted implementation strategies to integrate PrEP in FP clinics will include: (1) PrEP delivery by existing FP clinic staff, (2) health provider training, (3) PrEP technical assistance to coach and mentor providers, (4) joint supervision with Kisumu County health officials, and (5) stakeholder engagement. All core components of PrEP delivery—including screening for HIV risk, HIV testing, dispensing, adherence and risk reduction counseling, assessment of side effects, and provision of refills, or safety assessment—will be conducted by existing FP clinic staff as part of a standard care service package. The goal is to catalyze sustainable scale-up within existing infrastructures beyond the project. We will rigorously evaluate implementation outcomes and impact, using the RE-AIM (Reach, Effectiveness, Adoption, Implementation, Maintenance) framework, and we will use Organizational Readiness for Implementing Change (ORIC) and the Consolidated Framework for Implementation Science Research (CFIR) to assess readiness to implement and contextual enablers and barriers of implementation, including how clinics innovate efficient delivery systems.

Discussion

Anchoring PrEP delivery to existing FP systems and staffing has tremendous potential to address barriers that women face in accessing HIV prevention and PrEP care, including lack of time, cost, and stigma of visiting a facility solely for HIV prevention. The FP Plus Project will initiate preparation for full-scale and sustainable model of integration of comprehensive HIV prevention services, including PrEP implementation, in public health FP clinics in low-income settings.

Trial registration

Registered with ClinicalTrials.gov on December 14, 2020: NCT04666792

Sex Hormone Therapy and Tenofovir Diphosphate Concentration in Dried Blood Spots: Primary Results of the Interactions Between Antiretrovirals And Transgender Hormones Study

BACKGROUND

Sex hormone and preexposure prophylaxis (PrEP) drug interactions among transgender women (TGW), transgender men (TGM), and cisgender men (CGM) are not fully understood.

METHODS

TGM and TGW on at least 6 months of stable sex hormone therapy containing testosterone or estradiol (respectively) were enrolled in a 4-week study of directly observed dosing of daily oral coformulated emtricitabine and tenofovir disoproxil fumarate (FTC/TDF). TFV-DP in dried blood spots and sex hormones in serum were measured at weekly intervals. TFV-DP was compared with 2- and 4-week samples from Directly Observed Therapy Dried Blood Spots (DOT-DBS) Study (NCT02022657).

RESULTS

From May 2017 to June 2018, 24 TGM and 24 TGW were enrolled. Testosterone (total and free) and estradiol concentrations were comparable before and after 4 weeks of PrEP use in TGM and TGW, respectively. Historical controls included 17 cisgender women (CGW) and 15 CGM. TFV-DP concentrations at week 4 were comparable between TGW and TGM (mean difference, -6%; 95% confidence interval [CI], -21% to 12%; P = .47), comparable between TGW and CGM (mean difference, -12%; 95% CI, -27% to 7%; P = .21) and were lower among TGM compared with CGW (mean difference, -23%; 95% CI, -36% to -7%; P = .007). All persons in all groups were projected to reach the TFV-DP threshold that has been associated with high protection from human immunodeficiency virus.

CONCLUSIONS

CGM, TGM, and TGW had comparable TFV-DP concentrations in dried blood spots after 4 weeks of directly observed daily FTC/TDF PrEP use. Serum hormone concentrations were not affected by FTC/TDF PrEP use.

CLINICAL TRIALS REGISTRATION

NCT04050371.

Advances in long-acting injectables, implants, and vaginal rings for contraception and HIV prevention

Worldwide, women face compounding reproductive health risks, including human immunodeficiency virus (HIV), sexually-transmitted infections (STIs), and unintended pregnancy. Multipurpose prevention technologies (MPTs) offer combined protection against these overlapping risks in singular prevention products that offer potential for simplified use, lower burden, higher acceptability, and increased public health benefits. Over the past decade, substantial progress has been made in development of extended-release MPTs, which have further potential to grant sexual and reproductive health autonomy to women globally and to offer choice for women to accommodate varying needs during their reproductive lives. Here, we highlight the advances made in injectable, implant, and ring delivery forms, and the importance of incorporating end-user preferences early in the research and development of these products.

Pharmacokinetics, metabolism and serum concentrations of progestins used in contraception

Many different forms of hormonal contraception are used by millions of women worldwide. These contraceptives differ in the dose and type of synthetic progestogenic compound (progestin) used, as well as the route of administration and whether or not they contain estrogenic compounds. There is an increasing awareness that different forms of contraception and different progestins have different side-effect profiles, in particular their cardiovascular effects, effects on reproductive cancers and susceptibility to infectious diseases. There is a need to develop new methods to suit different needs and with minimal risks, especially in under-resourced areas. This requires a better understanding of the pharmacokinetics, metabolism, serum and tissue concentrations of progestins used in contraception as well as the biological activities of progestins and their metabolites via steroid receptors. Here we review the current knowledge on these topics and identify the research gaps. We show that there is a paucity of research on most of these topics for most progestins. We find that major impediments to clear conclusions on these topics include a lack of standardized methodologies, comparisons between non-parallel clinical studies and variability of data on serum concentrations between and within studies. The latter is most likely due, at least in part, to differences in intrinsic characteristics of participants. The review highlights the importance of insight on these topics in order to provide the best contraceptive options to women with minimal risks.

Depot Medroxyprogesterone Acetate and the Vaginal Microbiome as Modifiers of Tenofovir Diphosphate and Lamivudine Triphosphate Concentrations in the Female Genital Tract of Ugandan Women: Implications for Tenofovir Disoproxil Fumarate/Lamivudine in Preexposure Prophylaxis

BACKGROUND

Effective concentrations of antiretrovirals in the female genital tract (FGT) are critical for suppression of viral shedding or effective preexposure prophylaxis. The disposition of tenofovir diphosphate (TFV-DP) and emtricitabine triphosphate (FTC-TP) in the FGT have been previously described. Despite widespread use, however, lamivudine triphosphate (3TC-TP) exposure in the FGT is unknown. Depot medroxyprogesterone acetate (DMPA) and vaginal dysbiosis have been implicated in increased risk of human immunodeficiency virus (HIV) acquisition, but whether they alter TFV-DP or 3TC-TP exposure, and therefore compromise prevention efficacy, is unknown.

METHODS

Fifty premenopausal women living with HIV in Kampala, Uganda, and receiving daily tenofovir disoproxil fumarate/lamivudine were recruited. Ectocervical biopsies were obtained for quantification of TFV-DP and 3TC-TP using liquid chromatography-mass spectrometry. 16S ribosomal RNA gene sequencing was performed on DNA extracted from vaginal swabs. Wilcoxon rank-sum was used to test for differences between contraceptive groups.

RESULTS

3TC-TP concentrations were on average 17-fold greater than TFV-DP concentrations in cervical tissues. TFV-DP concentrations in cervical biopsies were 76% greater in DMPA users compared with women using nonhormonal contraception (n = 23 per group). Abundance of Lactobacillus in vaginal swabs was correlated with 3TC-TP concentrations in cervical tissues.

CONCLUSIONS

We found that TFV-DP concentrations were significantly greater in DMPA users compared with women using nonhormonal contraception, suggesting that prevention efficacy is unlikely to be compromised by DMPA use. Similar to reports of FTC-TP, 3TC-TP exposure was significantly greater than TFV-DP in cervical tissue and was correlated with abundance of Lactobacillus. These data support lamivudine as an option for preexposure prophylaxis.

CLINICAL TRIALS REGISTRATION

NCT03377608.

The effect of depot medroxyprogesterone acetate on tenofovir alafenamide in rhesus macaques

Prevention of HIV infection and unintended pregnancies are public health priorities. In sub-Saharan Africa, where HIV prevalence is highest, depot medroxyprogesterone acetate (DMPA) is widely used as contraception. Therefore, understanding potential interactions between DMPA and antiretrovirals is critical. Here, we use a macaque model to investigate the effect of DMPA on the pharmacology of the antiretroviral tenofovir alafenamide (TAF). Female rhesus macaques received 30 mg of DMPA (n = 9) or were untreated (n = 9). Macaques received a human equivalent dose of TAF (1.5 mg/kg) orally by gavage. Tenofovir (TFV) and TFV-diphosphate (TFV-DP) were measured in blood, secretions, and tissues over 72 h. The median area under the curve (AUC_0-72h) values for TFV-DP in peripheral blood mononuclear cells were similar in DMPA-treated (6991 fmol*h/10⁶ cells) and untreated controls (5256 fmol*h/10⁶ cells) (P = 0.174). Rectal tissue TFV-DP concentrations from DMPA+ animals [median: 20.23 fmol/mg of tissue (range: 4.94-107.95)] were higher than the DMPA- group [median: below the limit of quantification (BLOQ-11.92)], (P = 0.019). TFV-DP was not detectable in vaginal tissue from either group. A high-dose DMPA treatment in macaques was associated with increased rectal TFV-DP levels, indicating a potential tissue-specific drug-drug interaction. The lack of detectable TFV-DP in the vaginal tissue warrants further investigation of PrEP efficacy with single-agent TAF products. DMPA did not affect systemic TAF metabolism, with similar PBMC TFV-DP in both groups, suggesting that DMPA use should not alter the antiviral activity of TAF.

Pharmacokinetic and Pharmacodynamic Impacts of Depot Medroxyprogesterone Acetate Use on HIV Pre-exposure Prophylaxis in Women

BACKGROUND

Depot medroxyprogesterone acetate (DMPA) is a commonly used contraceptive in areas where use of tenofovir disoproxil fumarate and emtricitabine for HIV pre-exposure prophylaxis (PrEP) is increasing.

OBJECTIVES

We aimed to investigate the impact of DMPA on PrEP drug pharmacokinetics and pharmacodynamics in women using PrEP before and after DMPA administration.

METHODS

In this pilot study, 12 HIV-negative women ages 18-45 underwent biological sample collection at 3 time points: before study drug, after 2 weeks of daily PrEP use alone, and after 2 weeks of daily PrEP and concomitant DMPA use. We measured drug and drug metabolites in plasma, peripheral blood mononuclear cells, cervicovaginal fluid, cervical tissue, and rectal fluid after each 2-week course of PrEP. We measured HIV replication ex vivo in genital tissue biopsies and innate anti-HIV activity in cervicovaginal fluid before PrEP and after both courses. We compared drug concentrations after PrEP alone to after PrEP and DMPA in the same participant using Wilcoxon signed-rank tests. We used mixed effects linear regression models to compare pharmacodynamic measures for each participant at predrug baseline, after PrEP alone, and after PrEP and DMPA.

RESULTS

We found no significant differences in PrEP drug and drug metabolite concentrations in any compartment during concomitant DMPA use compared with use of PrEP alone, except for a reduction in emtricitabine concentration in cervical tissue. We found no difference in HIV replication in cervical tissue or anti-HIV activity in cervicovaginal fluid during concomitant DMPA and PrEP use compared with during PrEP use alone.

CONCLUSIONS

Concomitant use of DMPA does not clinically alter pharmacokinetics or pharmacodynamics of PrEP in women. These data support the safety of DMPA use in women using PrEP.

Contraception as a Potential Gateway to Pre-Exposure Prophylaxis: US Women's Pre-Exposure Prophylaxis Modality Preferences Align with Their Birth Control Practices

Addressing women's low uptake of HIV pre-exposure prophylaxis (PrEP) requires improved understanding of their product preferences. Such preferences should be contextualized according to other aspects of their reproductive health, including their contraception practices. We investigated women's preferences across 10 PrEP modalities currently available or under study and examined associations between PrEP modality preferences and contraception practices. Heterosexually active women recently engaged in care at Connecticut Planned Parenthood centers (n = 563) completed an online survey. Participants were presented with images and descriptions of 10 PrEP modalities and asked to indicate their preference and specify their reasoning in an open-response format. Participants also reported prior and current use of 16 contraception modalities along with relationship, sexual health, and sociodemographic characteristics. The sample included women ages 18-45 (45.3% 25 or younger) who were predominantly non-Hispanic black (35.7%) or white (33.7%). All PrEP modalities presented were preferred by at least some women, with daily pills (24.9%), injections (24.3%), and invisible implants (14.9%) preferred most commonly. Across all modalities, associated reasoning often centered around ease of use and comfort. Coincidence with contraception modality was the third-most common reason underlying women's preferences. Women currently using the analogous contraception modality versus never having used it had higher odds of preferring PrEP daily pills [adjusted odds ratio (AOR) = 2.03], injections (AOR = 8.45), invisible implants (AOR = 11.63), and vaginal rings (AOR = 8.66). Diversification of available PrEP modalities and prioritization of those coinciding with popular contraception practices-especially daily pills, injections, and implants-could optimize PrEP acceptability, encourage PrEP uptake, and ultimately reduce HIV incidence among women.

Reciprocal Modulation of Antiretroviral Drug and Steroid Receptor Function In Vitro

Millions of women are exposed simultaneously to antiretroviral drugs (ARVs) and progestin-based hormonal contraceptives. Yet the reciprocal modulation by ARVs and progestins of their intracellular functions is relatively unexplored. We investigated the effects of tenofovir disoproxil fumarate (TDF) and dapivirine (DPV), alone and in the presence of select steroids and progestins, on cell viability, steroid-regulated immunomodulatory gene expression, activation of steroid receptors, and anti-HIV-1 activity in vitro Both TDF and DPV modulated the transcriptional efficacy of a glucocorticoid agonist via the glucocorticoid receptor (GR) in the U2OS cell line. In TZM-bl cells, DPV induced the expression of the proinflammatory interleukin 8 (IL-8) gene while TDF significantly increased medroxyprogesterone acetate (MPA)-induced expression of the anti-inflammatory glucocorticoid-induced leucine zipper (GILZ) gene. However, peripheral blood mononuclear cell (PBMC) and ectocervical explant tissue viability and gene expression results, along with TZM-bl HIV-1 infection data, are reassuring and suggest that TDF and DPV, in combination with dexamethasone (DEX) or MPA, do not reciprocally modulate key biological effects in primary cells and tissue. We show for the first time that TDF induces progestogen-independent activation of the progesterone receptor (PR) in a cell line. The ability of TDF and DPV to influence GR and PR activity suggests that their use may be associated with steroid receptor-mediated off-target effects. This, together with cell line and individual donor gene expression responses in the primary models, raises concerns that reciprocal modulation may cause side effects in a cell- and donor-specific manner in vivo.

Integrating preexposure prophylaxis delivery in routine family planning clinics: A feasibility programmatic evaluation in Kenya

BACKGROUND

Young women account for a disproportionate fraction of new HIV infections in Africa and are a priority population for HIV prevention, including implementation of preexposure prophylaxis (PrEP). The overarching goal of this project was to demonstrate the feasibility of integrating PrEP delivery within routine family planning (FP) clinics to serve as a platform to efficiently reach at-risk adolescent girls and young women (AGYW) for PrEP in HIV high-burden settings.

METHODS AND FINDINGS

The PrEP Implementation in Young Women and Adolescents (PrIYA) program is a real-world implementation program to demonstrate integration of PrEP delivery for at-risk AGYW in FP clinics in Kisumu, Kenya. Between November 2017 and June 2018, women aged 15 to 45 from the general population seeking FP services at 8 public health clinics were universally screened for HIV behavioral risk factors and offered PrEP following national PrEP guidelines. We evaluated PrEP uptake and continuation, and robust Poisson regression methods were used to identify correlates of uptake and early continuation of PrEP, with age included as a one-knot linear spline. Overall, 1,271 HIV-uninfected women accessing routine FP clinics were screened for PrEP; the median age was 25 years (interquartile range [IQR]: 22-29), 627 (49%) were <24 years old, 1,026 (82%) were married, more than one-third (34%) had partners of unknown HIV status, and the vast majority (n = 1,200 [94%]) reported recent condom-less sex. Of 1,271 women screened, 278 (22%) initiated PrEP, and 114 (41%) returned for at least one refill visit after initiation. PrEP uptake was independently associated with reported male-partner HIV status (HIV-positive 94%, unknown 35%, HIV-negative 8%; p < 0.001) and marital status (28% unmarried versus married 21%; p = 0.04), and a higher proportion of women ≥24 years (26%; 191/740) initiated PrEP compared to 16% (87/531) of young women <24 years (p < 0.001). There was a moderate and statistically non-significant unadjusted increase in PrEP uptake among women using oral contraception pills (OCPs) compared to women using injectable or long-acting reversible contraception methods (OCP 28% versus injectable/implants/intrauterine devices [IUDs] 18%; p = 0.06). Among women with at least one post-PrEP initiation follow-up visit (n = 278), no HIV infection was documented during the project period. Overall, continuation of PrEP use at 1, 3, and 6 months post initiation was 41%, 24%, and 15%, respectively. The likelihood for early continuation of PrEP use (i.e., return for at least one PrEP refill within 45 days post initiation) was strongly associated with reported male-partner HIV status (HIV-positive 67%, -negative 39%, unknown 31%; overall effect p = 0.001), and a higher proportion of women ≥24 years old continued PrEP at 1 month compared with young women <24 years old (47% versus 29%; p = 0.002). For women ≥24 years old, the likelihood to continue PrEP use at 1 month post initiation increased by 3% for each additional year of a woman's age (adjusted prevalence ratio [PR]: 1.03; 95% confidence interval [CI]: 1.01-1.05; p = 0.01). In contrast, for women <24 years old, the likelihood of continuing PrEP for each additional year of a woman's age was high in magnitude (approximately 6%) but statistically non-significant (adjusted PR: 1.06; 95% CI: 0.97-1.16; p = 0.18). Frequently reported reasons for discontinuing PrEP were low perceived risk of HIV (25%), knowledge that partner was HIV negative (24%), experiencing side effects (20%), and pill burden (17%). Study limitations include lack of qualitative work to provide insights into women's decision-making on PrEP uptake and continuation, the small number of measured covariates imposed by the program data, and a nonrandomized design limiting definitive ascertainment of the robustness of a PrEP-dedicated nurse-led implementation strategy.

CONCLUSIONS

In this real-world PrEP implementation program in Kenya, integration of universal screening and counseling for PrEP in FP clinics was feasible, making this platform a potential "one-stop" location for FP and PrEP. There was a high drop-off in PrEP continuation, but a subset of women continued PrEP use at least through 1 month, possibly indicating further reflection or decision-making on PrEP use. Greater efforts to support PrEP normalization and persistence for African women are needed to help women navigate their decisions about HIV prevention preferences as their reproductive goals and HIV vulnerability evolve.

HIV-1 self-testing to improve the efficiency of pre-exposure prophylaxis delivery: a randomized trial in Kenya

Background

The introduction of pre-exposure prophylaxis (PrEP) for human immunodeficiency virus-1 (HIV-1) prevention in Africa presents new challenges for health systems that are already overburdened because PrEP delivery requires frequent clinic visits (generally every 3 months) for HIV-1 testing and PrEP refills. HIV-1 self-testing (HIVST) has the potential to improve the efficiency of PrEP delivery by decreasing the number of clinic visits. Here, we describe the rationale and design of a randomized, noninferiority trial designed to test the effectiveness and safety of using HIVST to support PrEP delivery in Kenya.

Methods

The JiPime-JiPrEP (Kiswahili for ‘Test Yourself, PrEP Yourself’) study is a three-arm randomized trial taking place in Thika, Kenya. Participants (n = 495) are eligible for enrollment if they are at least 18 years old, HIV-1 seronegative, and have been taking PrEP for 1 month. Three distinct participant types will be enrolled: men (n = 165) and women (n = 165) who are in mutually disclosed HIV-1 serodiscordant relationships, and women (n = 165) who are at HIV-1 risk and not in a known serodiscordant relationship. Participants in each of these subpopulations will be 1:1:1 randomized to: 1) the standard of care, with quarterly clinic visits; 2) oral HIVST, with biannual clinic visits plus oral HIVSTs to use at the quarters between those visits; or 3) blood-based HIVST, with biannual clinic visits plus blood-based HIVSTs. All participants will complete quantitative surveys and provide blood samples for the objective measurement of PrEP adherence at baseline, 6 months, and 12 months. The primary outcomes are PrEP adherence, PrEP continuation, and HIV-1 testing, measured at 6 months and secondarily at 12 months.

Discussion

The findings from this trial can help to understand how HIVST—a new HIV-1 testing technology—can support health systems in sub-Saharan Africa. Additionally, the findings can inform policy aimed at improving the efficiency of PrEP implementation and scale-up in Kenya.

Trial registration

ClinicalTrials.gov, NCT03593629. Retrospectively registered on 20 July 2018.

Electronic supplementary material

The online version of this article (10.1186/s13063-019-3521-2) contains supplementary material, which is available to authorized users.

Drug-drug interactions between feminizing hormone therapy and pre-exposure prophylaxis among transgender women: the iFACT study

INTRODUCTION

Concerns over potential drug-drug interactions (DDI) between feminizing hormone therapy (FHT) and pre-exposure prophylaxis (PrEP) have hampered uptake and adherence of PrEP among transgender women (TGW). To determine DDI between FHT and PrEP, we measured the pharmacokinetic (PK) parameters of blood plasma estradiol (E2) and tenofovir (TFV) in Thai TGW.

METHODS

Twenty TGW who never underwent orchiectomy and had not received injectable FHT within six months were enrolled between January and March 2018. FHT (E2 valerate and cyproterone acetate) were prescribed to participants at baseline until week 5, and then from week 8 until the end of study. Daily PrEP (tenofovir disoproxil fumarate/emtricitabine) was initiated at week 3 and continued without interruption. Intensive E2 PK parameters and testosterone concentration at 24 hours (C24 ) were measured at weeks 3 (without PrEP) and 5 (with PrEP), and intensive TFV PK parameters were measured at weeks 5 (with FHT) and 8 (without FHT).

RESULTS

Median (interquartile range) age, body mass index, and creatinine clearance were 21.5 (21-26) years, 20.6 (19.0-22.4) kg/m2 , and 116 (101-126.5) mL/min, respectively. The geometric mean (%CV) of area under curve from time zero to 24 hours (AUC0-24 ), maximum concentration (Cmax ), and C24 of E2 at weeks 3 and 5 were 775.13 (26.2) pg h/mL, 51.47 (26.9) pg/mL, and 15.15 (42.0) pg/mL; and 782.84 (39.6), 55.76 (32.9), and 14.32 (67.4), respectively. The geometric mean (%CV) of TFV AUC0-24 , Cmax , and C24 at weeks 5 and 8 were 2242.1 (26.5) ng h/mL, 353.9 (34.0) ng/mL, and 40.9 (31.4) ng/mL; and 2530.2 (31.3), 311.4 (30.0), and 49.8 (29.6), respectively. The geometric mean of TFV AUC0-24 and C24 at week 5 were significantly less than that at week 8 by 12% (p = 0.03) and 18% (p < 0.001), respectively. There were no significant changes in E2 PK parameters and median C24 of bioavailable testosterone between week 3 and week 5.

CONCLUSIONS

Our study demonstrated lower blood plasma TFV exposure in the presence of FHT, suggesting that FHT may potentially affect PrEP efficacy among TGW; but E2 exposure was not affected by PrEP. Further studies are warranted to determine whether these reductions in TFV are clinically significant. Clinical Trial Number: NCT03620734.

Preexposure Prophylaxis for the Prevention of HIV Infection: Evidence Report and Systematic Review for the US Preventive Services Task Force

IMPORTANCE

Effective prevention strategies for HIV infection are an important public health priority. Preexposure prophylaxis (PrEP) involves use of antiretroviral therapy (ART) daily or before and after sex to decrease risk of acquiring HIV infection.

OBJECTIVE

To synthesize the evidence on the benefits and harms of PrEP, instruments for predicting incident HIV infection, and PrEP adherence to inform the US Preventive Services Task Force.

DATA SOURCES

Ovid MEDLINE, the Cochrane Central Register of Controlled Trials, the Cochrane Database of Systematic Reviews, and EMBASE through June 2018, with surveillance through January 2019.

STUDY SELECTION

English-language placebo-controlled randomized clinical trials of oral PrEP with tenofovir disoproxil fumarate/emtricitabine or tenofovir disoproxil fumarate monotherapy; studies on the diagnostic accuracy of instruments for predicting incident HIV infection; and studies on PrEP adherence.

DATA EXTRACTION AND SYNTHESIS

Dual review of titles and abstracts, full-text articles, study quality, and data abstraction. Data were pooled using the Dersimonian and Laird random-effects model for effects of PrEP on HIV infection, mortality, and harms.

MAIN OUTCOMES AND MEASURES

HIV acquisition, mortality, and harms; adherence to PrEP; and diagnostic test accuracy and discrimination.

RESULTS

Fourteen RCTs (N = 18 837), 8 observational studies (N = 3884), and 7 studies of diagnostic accuracy (N = 32 279) were included. PrEP was associated with decreased risk of HIV infection vs placebo or no PrEP after 4 months to 4 years (11 trials; relative risk [RR], 0.46 [95% CI, 0.33-0.66]; I2 = 67%; absolute risk reduction [ARD], -2.0% [95% CI, -2.8% to -1.2%]). Greater adherence was associated with greater efficacy (RR with adherence ≥70%, 0.27 [95% CI, 0.19-0.39]; I2 = 0%) in 6 trials. PrEP was associated with an increased risk of renal adverse events (12 trials; RR, 1.43 [95% CI, 1.18-1.75]; I2 = 0%; ARD, 0.56% [95% CI, 0.09%-1.04%]) and gastrointestinal adverse events (12 trials; RR, 1.63 [95% CI, 1.26-2.11]; I2 = 43%; ARD, 1.95% [95% CI, 0.48%-3.43%]); most adverse events were mild and reversible. Instruments for predicting incident HIV infection had moderate discrimination (area under the receiver operating characteristic curve, 0.49-0.72) and require further validation. Adherence to PrEP in the United States in men who have sex with men varied widely (22%-90%).

CONCLUSIONS AND RELEVANCE

In adults at increased risk of HIV infection, PrEP with oral tenofovir disoproxil fumarate monotherapy or tenofovir disoproxil fumarate/emtricitabine was associated with decreased risk of acquiring HIV infection compared with placebo or no PrEP, although effectiveness decreased with suboptimal adherence.

PrEParing Women to Prevent HIV: An Integrated Theoretical Framework to PrEP Black Women in the United States

Preexposure prophylaxis (PrEP) with optimal adherence has demonstrated efficacy in reducing HIV incidence in women. Black women are disproportionately burdened by the HIV epidemic, accounting for more than half of all new HIV cases in women, thereby making PrEP an ideal prevention strategy for this group. However, to date, PrEP uptake by women in the United States has been slow. Further domestic research is needed to understand the multilevel factors related to PrEP awareness, uptake, and implementation in Black women. Our purpose was to review the current status of HIV prevention in Black women. We summarize clinical trials germane to federal approval of PrEP; discuss important PrEP studies focused on women, including non-oral options; and review multilevel barriers to PrEP uptake. Lastly, we discuss the use of an integrated theoretical framework to organize multilevel factors related to PrEP uptake by Black women in order to guide intervention development.

Pharmacology of Antiretrovirals in the Female Genital Tract for HIV Prevention

Preexposure prophylaxis (PrEP) is a powerful tool that, as part of a comprehensive prevention package, has potential to significantly impact the HIV epidemic. PrEP effectiveness is believed to be dependent on the exposure and efficacy of antiretrovirals at the site of HIV transmission. Clinical trial results as well as modeling and simulation indicate the threshold of adherence required for PrEP efficacy of emtricitabine/tenofovir disoproxil fumarate may differ between sites of HIV transmission with less forgiveness for missed doses in women exposed through genital tissue compared to people exposed through colorectal tissue. This suggests a role for local and host factors to influence mucosal pharmacology. Here we review the mucosal pharmacology of antiretrovirals in the female genital tract and explore potential determinants of PrEP efficacy. Host factors such as inflammation, coinfections, hormonal status, and the vaginal microbiome will be explored as well as the role of drug-metabolizing enzymes and transporters in regulating local drug exposure. The use of preclinical and early clinical models to predict clinical effectiveness is also discussed.

Scale up of PrEP integrated in public health HIV care clinics: a protocol for a stepped-wedge cluster-randomized rollout in Kenya

Background

Antiretroviral therapy (ART) for HIV-infected persons and pre-exposure prophylaxis (PrEP) for uninfected persons are extraordinarily effective strategies for HIV prevention. In Africa, the region which shoulders the highest HIV burden, HIV care is principally delivered through public health HIV care clinics, offering an existing platform to incorporate PrEP delivery and maximize ART and PrEP synergies. However, successfully bringing this integrated approach to scale requires an implementation science evaluation in public health settings.

Methods

The Partners Scale Up Project is a prospective, pragmatic implementation evaluation, designed as a stepped-wedge, cluster-randomized trial, operating at 24 clinics in Kenya. In collaboration with the Kenya Ministry of Health, we are catalyzing scaled implementation of PrEP delivery integrated in HIV care clinics. The intervention package includes staff training, clinic streamlined access to PrEP commodity from the Kenya Medical Supply Authority, and ongoing intensive technical assistance to rigorously assess how PrEP delivery is implemented. PrEP service delivery including retention efforts are conducted by the clinic staff with no additional resources from the project. Guided by the RE-AIM (Reach, Effectiveness, Adoption, Implementation, Maintenance) framework and Consolidated Framework for Implementation Science Research, project progress and learning are documented through ongoing monitoring and process evaluations, including chart abstraction and individual and key informant interviews, to evaluate pragmatic rollout and understand barriers and facilitators for successful PrEP delivery in this setting. In this staged rollout design, each step provides data for both pre-implementation (baseline) and implementation periods, and we will compare time points across steps in the baseline versus implementation periods.

Discussion

Cost-effective delivery models are urgently needed to maximize the public health impact of PrEP and ART. The Partners Scale Up Project will set the stage for full-scale PrEP implementation fully run and owned by the Kenya Ministry of Health. The work combines nationally sponsored PrEP delivery with technical support and implementation science from academic partners, defining a new but sustainable paradigm for public health collaboration.

Trial registration

Registered with ClinicalTrials.gov on February 14, 2017:NCT03052010.

Repeated administration of high-dose depot medroxyprogesterone acetate does not alter SHIVSF162p3 viral kinetics and tenofovir pharmacokinetics when delivered via intravaginal rings

BACKGROUND

Intravaginal rings (IVR) for HIV prevention will likely be used by women on depot medroxyprogesterone acetate (DMPA) hormonal contraception. We used pigtailed macaques to evaluate the effects of DMPA on tenofovir disoproxil fumarate (TDF) IVR pharmacokinetics and viral shedding.

METHODS

Mucosal tenofovir (TFV) levels were compared in SHIV_SF162p3 -negative DMPA-treated (n=4) and normally cycling (n=6) macaques receiving TDF IVRs. Plasma viremia and vaginal shedding were determined in groups of SHIV_SF162p3 -positive DMPA-treated (n=6) and normally cycling (n=5) macaques.

RESULTS

Similar median vaginal fluid TFV concentrations were observed in the DMPA-treated and cycling macaques over 4 weeks (1.2×10⁵ and 1.1.×10⁵  ng/mL, respectively). Median plasma viremia and vaginal shedding AUC of the DMPA-treated (2.73×10⁷ and 8.15×10⁴ copies/mL, respectively) and cycling macaques (3.98×10⁷ and 1.47×10³ copies/mL, respectively) were statistically similar.

CONCLUSIONS

DMPA does not affect TDF IVR pharmacokinetics or SHIV shedding.

The role of menopause in tenofovir diphosphate and emtricitabine triphosphate concentrations in cervical tissue

OBJECTIVE

Although postmenopausal (post-M) women have behavioral and biological risk factors for HIV infection, the activity of preexposure prophylaxis (PrEP) agents in older adults has not been well studied.

DESIGN

We used an ex-vivo approach to compare the tissue concentrations of tenofovir (TFV) diphosphate (TFVdp) and emtricitabine (FTC) triphosphate (FTCtp) in cervical tissues from premenopausal (pre-M) and post-M women.

METHOD

Cervical explants from 16 pre-M and 11 post-M women were incubated in 10-300 μg/ml TFV or FTC for 24 h. Explants were then snap frozen in liquid nitrogen and stored until analysis. TFVdp and FTCtp were quantified using tandem liquid chromatography-mass spectrometry.

RESULTS

Active metabolite concentrations of TFVdp were more than nine-fold lower in post-M explants (P < 0.05). The percentage of TFV converted to TFVdp in pre-M explants was 0.0038 [below the limit of quantification (BLQ)-0.5886] compared with 0.0004 (BLQ-0.0706) in post-M explants. The majority of FTCtp concentrations were BLQ. For both TFVdp and FTCtp, there was a trend for more unquantifiable concentrations in post-M vs. pre-M (TFV: 38 vs. 21%, P = 0.2; FTC: 71 vs. 52%, P = 0.2).

CONCLUSION

These findings could have implications in the use of nucleotide-based PrEP strategies targeted to older women. If validated in vivo, lower exposures of active nucleoside/tide metabolites could mean post-M women need higher doses of TFV-based PrEP to achieve protective efficacy.

PrEP as Peri-conception HIV Prevention for Women and Men

Daily oral tenofovir (TDF)-based pre-exposure prophylaxis (PrEP) is an effective HIV prevention strategy and recommended for men and women with substantial risk of HIV acquisition. The peri-conception period, the stage prior to pregnancy when condom use is necessarily reduced, has elevated HIV risk that can be mitigated by PrEP use. Data from a randomized trial suggest that peri-conception PrEP use by HIV-seronegative women does not increase the risk of pregnancy loss, birth defects or congenital anomalies, preterm birth, or infant growth faltering. Women considering PrEP use throughout pregnancy must weigh the known increased risk of HIV acquisition with unknown risks of drug effects on infant growth. PrEP has been used safely by HIV-seronegative men with HIV-seropositive female partners who have become pregnant. As an effective user-controlled HIV prevention strategy, PrEP offers autonomy and empowerment for HIV prevention and can be recommended alongside antiretroviral therapy, fertility screening, vaginal self-insemination, intercourse timed to peak fertility, medically assisted reproduction, and other safer conception strategies to provide multiple options. The integration of PrEP into safer conception programs is warranted and will safely reduce HIV transmission to women, men, and children during the peri-conception period.

Hormonal Contraceptives Differentially Suppress TFV and TAF Inhibition of HIV Infection and TFV-DP in Blood and Genital Tract CD4+ T cells

HIV prevention research is focused on combining antiretrovirals (ARV) and progestin contraceptives to prevent HIV infection and pregnancy. The possibility that progestins compromise ARV anti-HIV activity prompted us to evaluate the effects of progestins on tenofovir (TFV) and TFV-alafenamide (TAF) on HIV infection and intracellular TFV-diphosphate (TFV-DP) concentrations in blood and genital CD4+ T cells. Following incubation of blood CD4+ T cells with TFV or TAF, Medroxyprogesterone acetate (MPA), but not Levonorgestrel, Norethisterone or progesterone, suppressed the anti-HIV effect of TFV by reducing intracellular TFV-DP, but had no effect on TAF inhibition of infection or TFV-DP. In contrast, with genital CD4+ T cells, MPA suppressed TAF inhibition of HIV infection and lowered of TFV-DP concentrations without affecting TFV protection. These findings demonstrate that MPA selectively compromises TFV and TAF protection in blood and genital CD4+ T cells and suggests that MPA may decrease ARV protection in individuals who use ARV intermittently for prevention.

Recent advances in pre-exposure prophylaxis for HIV

Although pre-exposure prophylaxis (PrEP)-the use of antiretroviral drugs by non-infected people to prevent the acquisition of HIV-is a promising preventive option, important public health questions remain. Daily oral emtricitabine (FTC)-tenofovir disoproxil fumarate (TDF) is highly efficacious in preventing the acquisition of HIV in people at risk as a result of a range of different types of sexual exposure. There is good evidence of efficacy in women and men, and when men who have sex with men use event based dosing. Studies have been conducted in several countries and epidemics. Because adherence to this treatment varies greatly there are questions about its public health benefit. Oral FTC-TDF is extremely safe, with minimal impact on kidney, bone, or pregnancy outcomes, and there is no evidence that its effectiveness has been reduced by risk compensation during open label and programmatic follow-up. It is too early to assess the impact of this treatment on the incidence of sexually transmitted infections (STIs) at a population level. Many challenges remain. Access to pre-exposure prophylaxis is limited and disparities exist, including those governed by race and sex. Different pricing and access models need to be explored to avoid further widening inequalities. The optimal combination prevention program needs to be defined, and this will depend on local epidemiology, service provision, and cost effectiveness. This review updates the evidence base for pre-exposure prophylaxis regarding its effectiveness, safety, and risk compensation.

Offering pre-exposure prophylaxis for HIV prevention to pregnant and postpartum women: a clinical approach

Introduction: HIV prevention during pregnancy and lactation is critical for both maternal and child health. Pregnancy provides a critical opportunity for clinicians to elicit women’s vulnerabilities to HIV and offer HIV testing, treatment and referral and/or comprehensive HIV prevention options for the current pregnancy, the postpartum period and safer conception options for future pregnancies. In this commentary, we review the safety of oral pre-exposure prophylaxis with tenofovir/emtricitabine in pregnant and lactating women and suggest opportunities to identify pregnant and postpartum women at substantial risk of HIV. We then describe a clinical approach to caring for women who both choose and decline pre-exposure prophylaxis during pregnancy and postpartum, highlighting areas for future research.

Discussion: Evidence suggests that pre-exposure prophylaxis with tenofovir/emtricitabine is safe in pregnancy and lactation. Identifying women vulnerable to HIV and eligible for pre-exposure prophylaxis is challenging in light of the myriad of individual, community, and structural forces impacting HIV acquisition. Validated risk calculators exist for specific populations but have not been used to screen and offer HIV prevention methods. Partner testing and engagement of men living with HIV are additional means of reaching at-risk women. However, women’s vulnerabilities to HIV change over time. Combining screening for HIV vulnerability with HIV and/or STI testing at standard intervals during pregnancy is a practical way to prompt providers to incorporate HIV screening and prevention counselling. We suggest using shared decision-making to offer women pre-exposure prophylaxis as one of multiple HIV prevention strategies during pregnancy and postpartum, facilitating open conversations about HIV vulnerabilities, preferences about HIV prevention strategies, and choosing a method that best meets the needs of each woman.

Conclusion: Growing evidence suggests that pre-exposure prophylaxis with tenofovir/emtricitabine during pregnancy and lactation is safe and effective. Shared decision-making provides one approach to identify at-risk women and offers pre-exposure prophylaxis but requires implementation research in diverse clinical settings. Including pregnant and breastfeeding women in future HIV prevention research is critical for the creation of evidence-driven public health policies and clinical guidelines.

Transgender Women in Clinical Trials of Pre-Exposure Prophylaxis

Lessons were learned with trans women who participated (as volunteers and investigators) in trials of HIV pre-exposure prophylaxis (PrEP). Trans women are not men. Compared with men who have sex with men, trans women trial participants were more likely to be involved with transactional sex, had more sexual partners, and were less likely to have PrEP medications detected in blood. Trans women define themselves differently in different cultures. One best practice is to ask at least 2 gender questions: sex assigned at birth and current gender. More information is needed to fully situate PrEP efficacy for trans women, including analysis of drug–drug interactions between PrEP medications and feminizing hormones and PrEP drug penetration into neovaginal tissues. Including trans women in studies is helpful only if their participation is specifically reported, as could occur in a table of baseline characteristics of the enrolled cohort. Gender-affirming care is important to foster appropriate uptake and use of PrEP. Such care includes use of preferred pronouns and names, safety to use the bathroom of choice, and access to gender-affirming hormone therapy and surgery. The consistent finding that PrEP works when taken across diverse populations having diverse practices related to gender, sexual intercourse, and hormone use provides a basis for offering PrEP to people at substantial risk of acquiring HIV although some subgroups may not have been fully represented in trials. Nonetheless, specific PrEP implementation science for trans women (and men) is essential to develop best practices for PrEP delivery and use.

Pharmacologic Considerations for Preexposure Prophylaxis in Transgender Women

Studies of tenofovir disoproxil fumarate (TDF)-emtricitabine (FTC)-based preexposure prophylaxis (PrEP) have not focused on transgendered women who are at disproportionate risk of HIV acquisition. Concerns exist for drug interactions between cross-sex therapy (estradiol, progestins, and spironolactone) with tenofovir disoproxil fumarate-emtricitabine. This review assessed the experimental and theoretical risk for such drug interactions. It was found that none of these medications are implicated as major perpetrators of drug interactions, and the classes use different metabolic pathways for clearance, suggesting a low likelihood for interactions in either direction. Subanalyses of transgender women in Preexposure Prophylaxis Initiative suggested PrEP efficacy if adherence was high. Nevertheless, several research gaps were identified, particularly the need for controlled interaction studies in transgendered women, including effects on renal clearance, intracellular tenofovir diphosphate and emtricitabine triphosphate in target cells, as well as hormone effects on HIV susceptibility and immunity. PrEP should continue to be offered to transgender women while additional research is planned or pending.

Objective Measurement of Inaccurate Condom Use Reporting Among Women Using Depot Medroxyprogesterone Acetate for Contraception

Observational analyses have suggested that women using the injectable contraceptive depot medroxyprogesterone acetate (DMPA) may have heightened risk of acquiring HIV. However, those analyses were potentially confounded by sexual behavior, with possible differential condom use and reporting by women using DMPA versus no contraception. In a cross-sectional study, we measured the presence of a biomarker of recent condomless sex (Y chromosomal [Yc] DNA) in vaginal swabs from HIV-uninfected African women who had an HIV-infected partner and reported 100 % condom use. Half of the samples tested were from women reporting DMPA and half were from women using no contraception. Among 428 specimens tested (213 from DMPA users and 215 from women using no contraception), 32.0 % had Yc DNA detected, with a mean of 193 copies/10,000 human cells (range 0.1-8201). The frequency of detection did not differ by contraceptive use: 34.2 % of DMPA users versus 29.8 % of women using no contraception, adjusted odds ratio 1.3 (95 % confidence interval 0.9-2.0). These results suggest that inaccurate reporting of condom use by DMPA users may not account for the heightened risk of HIV acquisition among DMPA users in some observational studies.

Contraception for HIV-Infected Adolescents

Access to high-quality reproductive health care is important for adolescents and young adults with HIV infection to prevent unintended pregnancies, sexually transmitted infections, and secondary transmission of HIV to partners and children. As perinatally HIV-infected children mature into adolescence and adulthood and new HIV infections among adolescents and young adults continue to occur in the United States, medical providers taking care of such individuals often face issues related to sexual and reproductive health. Challenges including drug interactions between several hormonal methods and antiretroviral agents make decisions regarding contraceptive options more complex for these adolescents. Dual protection, defined as the use of an effective contraceptive along with condoms, should be central to ongoing discussions with HIV-infected young women and couples wishing to avoid pregnancy. Last, reproductive health discussions need to be integrated with discussions on HIV care, because a reduction in plasma HIV viral load below the level of detection (an "undetectable viral load") is essential for the individual's health as well as for a reduction in HIV transmission to partners and children.

Effectiveness and safety of oral HIV preexposure prophylaxis for all populations

OBJECTIVE

Preexposure prophylaxis (PrEP) offers a promising new approach to HIV prevention. This systematic review and meta-analysis evaluated the evidence for use of oral PrEP containing tenofovir disoproxil fumarate as an additional HIV prevention strategy in populations at substantial risk for HIV based on HIV acquisition, adverse events, drug resistance, sexual behavior, and reproductive health outcomes.

DESIGN

Rigorous systematic review and meta-analysis.

METHODS

A comprehensive search strategy reviewed three electronic databases and conference abstracts through April 2015. Pooled effect estimates were calculated using random-effects meta-analysis.

RESULTS

Eighteen studies were included, comprising data from 39 articles and six conference abstracts. Across populations and PrEP regimens, PrEP significantly reduced the risk of HIV acquisition compared with placebo. Trials with PrEP use more than 70% demonstrated the highest PrEP effectiveness (risk ratio = 0.30, 95% confidence interval: 0.21-0.45, P < 0.001) compared with placebo. Trials with low PrEP use did not show a significantly protective effect. Adverse events were similar between PrEP and placebo groups. More cases of drug-resistant HIV infection were found among PrEP users who initiated PrEP while acutely HIV-infected, but incidence of acquiring drug-resistant HIV during PrEP use was low. Studies consistently found no association between PrEP use and changes in sexual risk behavior. PrEP was not associated with increased pregnancy-related adverse events or hormonal contraception effectiveness.

CONCLUSION

PrEP is protective against HIV infection across populations, presents few significant safety risks, and there is no evidence of behavioral risk compensation. The effective and cost-effective use of PrEP will require development of best practices for fostering uptake and adherence among people at substantial HIV risk.

What's new for antiretroviral treatment in women with HIV

Currently, women represent 52% of persons infected with HIV worldwide and 23% of those in the United States. Combination antiretroviral therapy (cART) has resulted in remarkable reductions in HIV-associated morbidity and mortality, and has dramatically improved life expectancy. Treatment guidelines do not differ for HIV-infected men and non-pregnant women. However, clinical trials of antiretroviral agents have limited female enrolment, and results from these predominantly male studies are extrapolated to the female population. Furthermore, many of these studies do not report gender subgroup analyses, and those that do are underpowered to detect differences between men and women, limiting the ability to assess if results are equally applicable to both sexes. Women may have differential responses to and adverse events from cART. A limited number of female-only clinical trials have demonstrated that female recruitment and retention in these studies is feasible. Therefore, urgent attention is required to improve the body of knowledge regarding clinical efficacy, safety and tolerability of cART in women. In particular, women living with HIV are faced with various sexual and reproductive health concerns that may influence choice of cART. These include potential interactions with hormonal contraception, safety in pregnancy, and the impact of the transition through menopause and development of age-related comorbidities. Finally, the ongoing advances in biomedical HIV prevention, particularly pre-exposure prophylaxis (PrEP), provide an enormous opportunity to enhance HIV prevention in high-risk women, in efforts to further reduce global burden of the pandemic.

Safety of oral tenofovir disoproxil fumarate-based pre-exposure prophylaxis for HIV prevention

INTRODUCTION

Tenofovir disoproxil fumarate (TDF)-based pre-exposure prophylaxis is a novel HIV prevention strategy for individuals at increased sexual risk for HIV infection. For any biomedical prevention intervention, the bar for tolerating adverse effects in healthy persons is high compared to therapeutic interventions.

AREAS COVERED

We provide a concise summary of the clinical safety of TDF-based pre-exposure prophylaxis with focus on TDF-related effects on tolerability, kidney function, bone density, HIV resistance, sexual and reproductive health. The evidence base for this review is derived from a literature search of both randomized and observational studies evaluating efficacy and safety of TDF-based PrEP, TDF alone or in combination with emtricitabine, identified from PUBMED and EMBASE electronic databases, clinicaltrials.gov and major HIV conferences.

EXPERT OPINION

TDF-based pre-exposure prophylaxis is a potent intervention against HIV acquisition when taken which is generally safe and well tolerated. The risk of the small, non-progressive, and reversible decline in glomerular filtration rate and bone mineral density as well as the potential selection for drug resistance associated with PrEP are outweighed, at the population level and broadly for individuals, by PrEP's substantial reduction in the risk of HIV infection.

HIV pre-exposure prophylaxis in transgender women: a subgroup analysis of the iPrEx trial

Background

Oral emtricitabine-tenofovir disoproxil fumarate (FTC/TDF) pre-exposure prophylaxis (PrEP) is used to prevent the sexual acquisition of HIV. Transgender women (TGW) have unique characteristics that may relate to PrEP use, effectiveness, and safety.

Methods

The iPrEx trial was a randomized controlled trial (RCT) of oral FTC/TDF PrEP versus placebo among men who have sex with men (MSM) and TGW, followed by an open label extension (OLE). Drug concentrations were measured in blood by liquid chromatography and tandem mass spectroscopy.

Findings

Of the 2499 participants enrolled in the RCT, 29 (1%) identified as women, 296 (12%) identified as “trans”, 14 (1%) identified as men but reported use of feminizing hormones, such that 339 (14%) reported one or more of these characteristics (TGW). Compared with MSM, TGW more frequently reported transactional sex, receptive anal intercourse without a condom, or more than 5 partners in the past 3 months. Among TGW, there were 11 HIV infections in the active arm and 10 in the placebo arm, representing a hazard ratio of 1.1 (95% CI: 0.5 to 2.7). Among active arm participants, drug was detected in none of the TGW at the seroconversion visit, 18% (6/37) of seronegative TGW (P=0.31), and 52% (58/111) of seronegative MSM (P < 0.0001). PrEP use was not linked to behavioral indicators of HIV risk among TGW, while MSM at highest risk were more adherent.

Interpretation

There were no HIV infections among TGW having drug concentrations commensurate with use of 4 or more FTC/TDF tablets per week. TGW receiving PrEP had low drug concentrations, especially at times of potential HIV exposure, leading to no PrEP effectiveness among this subgroup.

Funding

U.S. National Institutes of Health and the Bill and Melinda Gates Foundation; study medication was donated by Gilead Sciences.