Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 75
Filter
2.
PLoS Med ; 21(3): e1004360, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38502656

ABSTRACT

BACKGROUND: Adjuvants are widely used to enhance and/or direct vaccine-induced immune responses yet rarely evaluated head-to-head. Our trial directly compared immune responses elicited by MF59 versus alum adjuvants in the RV144-like HIV vaccine regimen modified for the Southern African region. The RV144 trial of a recombinant canarypox vaccine vector expressing HIV env subtype B (ALVAC-HIV) prime followed by ALVAC-HIV plus a bivalent gp120 protein vaccine boost adjuvanted with alum is the only trial to have shown modest HIV vaccine efficacy. Data generated after RV144 suggested that use of MF59 adjuvant might allow lower protein doses to be used while maintaining robust immune responses. We evaluated safety and immunogenicity of an HIV recombinant canarypox vaccine vector expressing HIV env subtype C (ALVAC-HIV) prime followed by ALVAC-HIV plus a bivalent gp120 protein vaccine boost (gp120) adjuvanted with alum (ALVAC-HIV+gp120/alum) or MF59 (ALVAC-HIV+gp120/MF59) or unadjuvanted (ALVAC-HIV+gp120/no-adjuvant) and a regimen where ALVAC-HIV+gp120 adjuvanted with MF59 was used for the prime and boost (ALVAC-HIV+gp120/MF59 coadministration). METHODS AND FINDINGS: Between June 19, 2017 and June 14, 2018, 132 healthy adults without HIV in South Africa, Zimbabwe, and Mozambique were randomized to receive intramuscularly: (1) 2 priming doses of ALVAC-HIV (months 0 and 1) followed by 3 booster doses of ALVAC-HIV+gp120/MF59 (months 3, 6, and 12), n = 36; (2) 2 priming doses of ALVAC-HIV (months 0 and 1) followed by 3 booster doses of ALVAC-HIV+gp120/alum (months 3, 6, and 12), n = 36; (3) 4 doses of ALVAC-HIV+gp120/MF59 coadministered (months 0, 1, 6, and 12), n = 36; or (4) 2 priming doses of ALVAC-HIV (months 0 and 1) followed by 3 booster doses of ALVAC-HIV+gp120/no adjuvant (months 3, 6, and 12), n = 24. Primary outcomes were safety and occurrence and mean fluorescence intensity (MFI) of vaccine-induced gp120-specific IgG and IgA binding antibodies at month 6.5. All vaccinations were safe and well-tolerated; increased alanine aminotransferase was the most frequent related adverse event, occurring in 2 (1.5%) participants (1 severe, 1 mild). At month 6.5, vaccine-specific gp120 IgG binding antibodies were detected in 100% of vaccinees for all 4 vaccine groups. No significant differences were seen in the occurrence and net MFI of vaccine-specific IgA responses between the ALVAC-HIV+gp120/MF59-prime-boost and ALVAC-HIV+gp120/alum-prime-boost groups or between the ALVAC-HIV+gp120/MF59-prime-boost and ALVAC-HIV+gp120/MF59 coadministration groups. Limitations were the relatively small sample size per group and lack of evaluation of higher gp120 doses. CONCLUSIONS: Although MF59 was expected to enhance immune responses, alum induced similar responses to MF59, suggesting that the choice between these adjuvants may not be critical for the ALVAC+gp120 regimen. TRIAL REGISTRATION: HVTN 107 was registered with the South African National Clinical Trials Registry (DOH-27-0715-4894) and ClinicalTrials.gov (NCT03284710).


Subject(s)
AIDS Vaccines , Alum Compounds , HIV Infections , HIV-1 , Polysorbates , Squalene , Adult , Humans , Adjuvants, Immunologic , AIDS Vaccines/adverse effects , HIV Antibodies , HIV Infections/prevention & control , Immunogenicity, Vaccine , Immunoglobulin A , Immunoglobulin G , Vaccines, Combined , Vaccines, Synthetic
3.
BMJ Open ; 14(3): e075381, 2024 Mar 12.
Article in English | MEDLINE | ID: mdl-38479746

ABSTRACT

INTRODUCTION: Oral pre-exposure prophylaxis (PrEP) is a highly effective HIV prevention method; however, uptake and persistence have been low among southern African women. A dual prevention pill (DPP) that combines PrEP with oral contraception (OC) may increase PrEP use and better meet women's sexual and reproductive health needs. We will gauge the DPP's acceptability in two cross-over clinical trials. METHODS AND ANALYSIS: PC952 (Zimbabwe) and PC953 (South Africa) will compare acceptability, adherence and preference for an over-encapsulated DPP versus PrEP and OCs taken separately. HIV-negative, non-pregnant cisgender females in Johannesburg, South Africa (n=96, 16-40 years) and Harare, Zimbabwe (n=30, 16-24 years) will be randomised 1:1 to the order of regimens-DPP or two separate tablets-each used for three 28-day cycles, followed by a 6-month choice period in South Africa. Monthly clinic visits include HIV and pregnancy testing; safety assessments and risk reduction and adherence counselling. We will assess adherence (monthly) based on tenofovir diphosphate drug levels in dried blood spots and by self-report. We will evaluate acceptability (monthly) and preference (end of cross-over) via computer-assisted self-interviewing and in-depth interviews with a subset of participants. Data collection started in September 2022 and ended in January 2024. ETHICS AND DISSEMINATION: PC952 was approved by the Ministry of Health and Child Care, Medical Research Council, Research Council and Medicines Control Authority of Zimbabwe; the Chitungwiza City Health Ethics Committee; and the Joint Research Ethics Committee for the University of Zimbabwe Faculty of Medicine and Health Sciences and Parirenyatwa Group of Hospitals. PC953 was approved by the South African Health Products Regulatory Authority and the University of the Witwatersrand's Human Research Ethics Committee. The Population Council IRB approved both studies. We will disseminate results in open-access journals, clinical trials registries, and at local and international meetings and conferences. TRIAL REGISTRATION NUMBERS: NCT04778514, NCT04778527.


Subject(s)
Contraception , HIV Infections , Pre-Exposure Prophylaxis , Female , Humans , Anti-HIV Agents/therapeutic use , Cross-Over Studies , HIV Infections/epidemiology , HIV Infections/prevention & control , Pre-Exposure Prophylaxis/methods , South Africa/epidemiology , Zimbabwe , Randomized Controlled Trials as Topic , Adolescent , Young Adult , Adult
4.
J Infect Dis ; 229(4): 1158-1165, 2024 Apr 12.
Article in English | MEDLINE | ID: mdl-38099506

ABSTRACT

BACKGROUND: Confounding introduced by individuals' sexual risk behavior is potentially a significant source of bias in HIV-1 prevention intervention studies. To more completely account for sexual behaviors when assessing the efficacy of the monthly dapivirine ring, a new longer-acting HIV-1 prevention option for women, we estimated per-sex-act risk reduction associated with product use. METHODS: We conducted a secondary analysis of data from MTN-020/ASPIRE, a phase 3, randomized, placebo-controlled efficacy trial of the dapivirine ring that recruited HIV-uninfected, African women aged 18-45 years. With cumulative sex acts as the time scale, we used multivariable Cox regression with inverse probability of censoring weights to estimate HIV-1 risk reduction associated with a rate of dapivirine release indicative of consistent product use. RESULTS: Women in the dapivirine ring group (n = 1187) had an estimated incidence rate of 2.3 (95% confidence interval [CI], 1.8-3.1) HIV-1 acquisition events per 10 000 sex acts versus 3.6 (95% CI, 2.9-4.4) per 10 000 acts in the placebo group (n = 1187). Dapivirine release indicative of consistent ring use was associated with a 63% (95% CI, 33%-80%) per-sex-act HIV-1 risk reduction. CONCLUSIONS: These results support the efficacy of the dapivirine vaginal ring for HIV-1 prevention and help to inform decision-making for women, providers, and policymakers regarding product use. CLINICAL TRIALS REGISTRATION: NCT01617096.


Subject(s)
Anti-HIV Agents , Contraceptive Devices, Female , HIV Infections , HIV Seropositivity , HIV-1 , Pyrimidines , Female , Humans , Anti-HIV Agents/therapeutic use , HIV Infections/prevention & control , HIV Infections/epidemiology , Risk Reduction Behavior , Adolescent , Young Adult , Adult , Middle Aged
5.
J Acquir Immune Defic Syndr ; 95(1): 65-73, 2024 01 01.
Article in English | MEDLINE | ID: mdl-38055292

ABSTRACT

BACKGROUND: Pregnancy represents a period of high HIV acquisition risk. Safety data for the monthly dapivirine vaginal ring (DVR) during pregnancy are limited. Here, we report data from the first 2 cohorts of pregnant participants in MTN-042/DELIVER, a phase 3b, randomized, open-label safety trial of DVR and oral tenofovir disoproxil fumarate/emtricitabine (TDF/FTC). MTN-042 is being conducted in 3 cohorts beginning with later gestational ages when risks of drug exposure are less. METHODS: Eligible pregnant individuals aged 18-40 years in Malawi, South Africa, Uganda, and Zimbabwe were randomized 2:1 to monthly DVR or daily TDF/FTC. Participants in cohort 1 initiated product use between 36 weeks 0 days (36 0/7 weeks) and 37 6/7 weeks gestation; participants in cohort 2 initiated product use between 30 0/7 and 35 6/7 weeks gestation. All participants continued product use until delivery or 41 6/7 weeks gestation. Pregnancy outcomes and complications were assessed and summarized using descriptive statistics and compared with local background rates obtained through a separate chart review. RESULTS: One-hundred and fifty participants were enrolled into cohort 1 with 101 randomized to DVR and 49 to TDF/FTC. One-hundred and fifty-seven participants were enrolled into cohort 2 with 106 randomized to DVR and 51 to TDF/FTC. In both cohorts, pregnancy complications were rare and similar to local background rates. CONCLUSION: In this first study of a long-acting HIV prevention agent in pregnancy, adverse pregnancy outcomes and complications were uncommon when DVR and TDF/FTC were used in the third trimester of pregnancy, suggesting a favorable safety profile for both prevention products.


Subject(s)
HIV Infections , Female , Pregnancy , Humans , HIV Infections/prevention & control , Emtricitabine , Gestational Age , Malawi , Tenofovir/adverse effects
6.
J Acquir Immune Defic Syndr ; 95(1): 35-41, 2024 01 01.
Article in English | MEDLINE | ID: mdl-37732881

ABSTRACT

BACKGROUND: Clinical trials of dapivirine (DPV) vaginal ring have shown it is safe, effective, and desired by women as an HIV prevention option. The risk of drug resistance is a potential concern for DPV ring users who acquire HIV. We conducted a comprehensive resistance evaluation of plasma samples from the women who seroconverted during the Microbicide Trials Network-025/HIV Open-label Prevention Extension (HOPE) study of DPV ring. METHODS: Plasma collected on the visit at which seroconversion was detected was tested by next-generation sequencing with unique molecular identifiers for non-nucleoside reverse transcriptase inhibitor (NNRTI) drug resistance mutations (DRM) present at ≥1% frequency. Bulk-cloned plasma-derived recombinant HIV was phenotyped in a TZM-bl-based assay for susceptibility to DPV and other NNRTI. HIV-1 RNA was retrospectively quantified in plasma samples collected before HIV seroconversion. RESULTS: Among 38 participants who seroconverted in HOPE, 7 (18%) had NNRTI DRM detected by next-generation sequencing with unique molecular identifiers including A98G, K103N, V106M, E138A, and V179D. Six of 7 samples with NNRTI DRM had <3-fold reduction in susceptibility to DPV. Only 1 sample with K103N and V179I polymorphism had 9-fold reduction in susceptibility to DPV, but this genotype occurred in an individual who did not use DPV ring, likely indicating transmitted resistance. Detection of NNRTI resistance was not higher in individuals who remained on DPV ring >3 months after acquiring HIV infection. CONCLUSIONS: NNRTI resistance among women who seroconverted during HOPE was infrequent and selection of DPV-specific mutations was not detected. DPV ring is considered a safe and effective option for HIV prevention in women.


Subject(s)
Anti-HIV Agents , Contraceptive Devices, Female , HIV Infections , HIV Seropositivity , Female , Humans , Anti-HIV Agents/pharmacology , Anti-HIV Agents/therapeutic use , HIV Infections/drug therapy , HIV Infections/prevention & control , Retrospective Studies , Reverse Transcriptase Inhibitors/therapeutic use
7.
Nat Commun ; 14(1): 8299, 2023 Dec 14.
Article in English | MEDLINE | ID: mdl-38097552

ABSTRACT

The Antibody Mediated Prevention (AMP) trials (NCT02716675 and NCT02568215) demonstrated that passive administration of the broadly neutralizing monoclonal antibody VRC01 could prevent some HIV-1 acquisition events. Here, we use mathematical modeling in a post hoc analysis to demonstrate that VRC01 influenced viral loads in AMP participants who acquired HIV. Instantaneous inhibitory potential (IIP), which integrates VRC01 serum concentration and VRC01 sensitivity of acquired viruses in terms of both IC50 and IC80, follows a dose-response relationship with first positive viral load (p = 0.03), which is particularly strong above a threshold of IIP = 1.6 (r = -0.6, p = 2e-4). Mathematical modeling reveals that VRC01 activity predicted from in vitro IC80s and serum VRC01 concentrations overestimates in vivo neutralization by 600-fold (95% CI: 300-1200). The trained model projects that even if future therapeutic HIV trials of combination monoclonal antibodies do not always prevent acquisition, reductions in viremia and reservoir size could be expected.


Subject(s)
HIV Infections , HIV-1 , Humans , Antibodies, Neutralizing , Viral Load , HIV Antibodies , Models, Theoretical
8.
Front Reprod Health ; 5: 1279124, 2023.
Article in English | MEDLINE | ID: mdl-38034413

ABSTRACT

The global burden of HIV remains unacceptably high despite significant progress made in HIV treatment and prevention. There is an urgent need to scale up the comprehensive HIV prevention strategies that include pre-exposure prophylaxis (PrEP). Oral PrEP is highly effective in preventing HIV acquisition when taken regularly, but this remains a challenge for some at-risk individuals. Therefore, there is a need for other HIV prevention options. The dapivirine vaginal ring (DVR) and long-acting injectable cabotegravir (CAB-LA) are novel biomedical interventions that are safe and efficacious for HIV pre-exposure prophylaxis, as demonstrated in recently completed clinical trials. Timely roll-out and scalability of efficacious interventions depend on the registration process with the national medicine regulatory authorities (NMRAs). The Medicines Control Authority of Zimbabwe (MCAZ) was the first NMRA globally to approve the DVR in July 2021 and the first in Africa to approve CAB-LA for HIV prevention in July 2022. The regulatory review process for DVR and CAB-LA by MCAZ took 4.5 and 5.5 months, respectively. This efficient review process of the two interventions by MCAZ, a regulatory body in a resource-limited setting, provides important lessons to shorten timelines between the completion of the clinical development process and the registration of essential medicines.

9.
Nat Commun ; 14(1): 7813, 2023 Nov 28.
Article in English | MEDLINE | ID: mdl-38016958

ABSTRACT

Broadly neutralizing monoclonal antibodies (mAbs) are being developed for HIV-1 prevention. Hence, these mAbs and licensed oral pre-exposure prophylaxis (PrEP) (tenofovir-emtricitabine) can be concomitantly administered in clinical trials. In 48 US participants (men and transgender persons who have sex with men) who received the HIV-1 mAb VRC01 and remained HIV-free in an antibody-mediated-prevention trial (ClinicalTrials.gov #NCT02716675), we conduct a post-hoc analysis and find that VRC01 clearance is 0.08 L/day faster (p = 0.005), and dose-normalized area-under-the-curve of VRC01 serum concentration over-time is 0.29 day/mL lower (p < 0.001) in PrEP users (n = 24) vs. non-PrEP users (n = 24). Consequently, PrEP users are predicted to have 14% lower VRC01 neutralization-mediated prevention efficacy against circulating HIV-1 strains. VRC01 clearance is positively associated (r = 0.33, p = 0.03) with levels of serum intestinal Fatty Acid Binding protein (I-FABP), a marker of epithelial intestinal permeability, which is elevated upon starting PrEP (p = 0.04) and after months of self-reported use (p = 0.001). These findings have implications for the evaluation of future HIV-1 mAbs and postulate a potential mechanism for mAb clearance in the context of PrEP.


Subject(s)
Anti-HIV Agents , HIV Infections , HIV-1 , Pre-Exposure Prophylaxis , Male , Adult , Humans , Tenofovir/therapeutic use , Emtricitabine/therapeutic use , HIV Infections/drug therapy , Anti-HIV Agents/therapeutic use , Antibodies, Monoclonal/therapeutic use
10.
Nat Med ; 29(11): 2748-2752, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37798438

ABSTRACT

Pre-exposure prophylaxis (PrEP) with tenofovir (TFV) disoproxil fumarate and emtricitabine administered orally daily is effective in preventing human immunodeficiency virus (HIV) acquisition in both men and women with sufficient adherence; however, the adherence-efficacy relationship in cisgender women has not been well established. We calculated the adherence-efficacy curve for cisgender women by using HIV incidence and plasma TFV concentration data from three trials (FEM-PrEP, VOICE and Partners PrEP). We imputed TFV diphosphate (TFV-DP) concentrations, a measure of long-term adherence, from TFV quantification by using data from the HIV Prevention Trials Network 082 study, which measured both TFV-DP and TFV concentrations. Two, four and seven pills per week reduced HIV incidence by 59.3% (95% credible interval (CrI) 29.9-95.8%), 83.8% (95% CI 51.7-99.8%) and 95.9% (95% CI 72.6-100%), respectively. Our adherence-efficacy curve can be validated and updated by HIV prevention studies that directly measure TFV-DP concentrations. The curve suggests that high adherence confers high protection in cisgender women. However, the lower efficacy with partial adherence highlights the need for new PrEP products and interventions to increase adherence.


Subject(s)
Anti-HIV Agents , HIV Infections , Pre-Exposure Prophylaxis , Male , Humans , Female , Anti-HIV Agents/therapeutic use , HIV Infections/epidemiology , HIV Infections/prevention & control , HIV Infections/drug therapy , HIV , Emtricitabine/therapeutic use , Tenofovir/therapeutic use , Medication Adherence
11.
AIDS Behav ; 2023 Sep 28.
Article in English | MEDLINE | ID: mdl-37768427

ABSTRACT

To develop effective PrEP adherence interventions, it is important to understand the interplay between disclosure of pre-exposure prophalxis (PrEP) use, social support, and PrEP adherence. We leveraged the HPTN 082 study conducted among 451 adolescent girls and young women (AGYW) (ages 16 to 25 years, 2016 to 2019) in South Africa and Zimbabwe. Among the 349 who had month three disclosure and PrEP adherence data, 60% (n = 206) felt supported by adults, and 89% (n = 309) disclosed PrEP use to at least one person. PrEP disclosure was not associated with increased adherence, measured by intracellular tenofovir-diphosphate concentrations in dried blood spots. Women who reported having supportive adults, and disclosed to their parents, had higher adherence at 6 months with an increase of 177 fmol/punch (95% CI 12 to 343, t = 2.11, p = 0.04). PrEP interventions that help AGYW identify supportive relationships and effectively communicate the benefits of PrEP may improve PrEP adherence.Clinicaltrials.gov ID number: NCT02732730.

13.
Nat Rev Dis Primers ; 9(1): 42, 2023 08 17.
Article in English | MEDLINE | ID: mdl-37591865

ABSTRACT

The AIDS epidemic has been a global public health issue for more than 40 years and has resulted in ~40 million deaths. AIDS is caused by the retrovirus, HIV-1, which is transmitted via body fluids and secretions. After infection, the virus invades host cells by attaching to CD4 receptors and thereafter one of two major chemokine coreceptors, CCR5 or CXCR4, destroying the host cell, most often a T lymphocyte, as it replicates. If unchecked this can lead to an immune-deficient state and demise over a period of ~2-10 years. The discovery and global roll-out of rapid diagnostics and effective antiretroviral therapy led to a large reduction in mortality and morbidity and to an expanding group of individuals requiring lifelong viral suppressive therapy. Viral suppression eliminates sexual transmission of the virus and greatly improves health outcomes. HIV infection, although still stigmatized, is now a chronic and manageable condition. Ultimate epidemic control will require prevention and treatment to be made available, affordable and accessible for all. Furthermore, the focus should be heavily oriented towards long-term well-being, care for multimorbidity and good quality of life. Intense research efforts continue for therapeutic and/or preventive vaccines, novel immunotherapies and a cure.


Subject(s)
Acquired Immunodeficiency Syndrome , Epidemics , HIV Infections , Humans , HIV Infections/drug therapy , HIV Infections/epidemiology , Quality of Life , Immunotherapy
14.
J Int AIDS Soc ; 26 Suppl 2: e26115, 2023 07.
Article in English | MEDLINE | ID: mdl-37439069

ABSTRACT

INTRODUCTION: The burden of HIV in sub-Saharan Africa (SSA) remains unacceptably high, and disproportionately affects girls and women. While the introduction of oral HIV pre-exposure prophylaxis (PrEP) in 2012 revolutionized HIV prevention, its effectiveness is dependent on user adherence and its implementation in SSA has faced numerous challenges. Patient-level, interpersonal and structural barriers, including, for example, daily pill burden, side effects, lack of partner support, testing and disclosure, and costs have been found to reduce adherence to oral PrEP. DISCUSSION: Long-acting extended delivery (LAED) formulations for PrEP, such as injectable long-acting cabotegravir (CAB-LA) and dapivirine vaginal ring (DPV-VR) are critical additions to the HIV prevention toolkit and are especially important for populations such as adolescent girls and young women (AGYW) and other key populations who remain at significant risk of HIV acquisition while facing substantial barriers to preventive services. These LAED formulations have been shown to result in better adherence and fewer side effects, with CAB-LA being superior to oral PrEP in reducing the risk of HIV acquisition. They can be used to overcome user burden and adherence challenges. However, the successful rollout of the DPV-VR and CAB-LA may be hampered by issues such as a shortage of healthcare providers (HCPs), inadequate parenteral medication infrastructure, increased workload for HCPs, patient concerns, the price of the medications and the possibility of drug resistance. CONCLUSIONS: SSA must develop laboratory capabilities for monitoring patients on LAED formulations and enhance research on developing more non-injectable LAED formulations. There is a need to train and retain more HCPs, implement task shifting, invest in healthcare infrastructure and integrate healthcare services. To reduce costs and improve availability, the region must advocate for patent license waivers for LAED formulations and procure drugs collectively as a region.


Subject(s)
HIV Infections , Adolescent , Humans , Female , HIV Infections/drug therapy , HIV Infections/prevention & control , Disclosure , Health Facilities , Health Personnel , Africa South of the Sahara
15.
EBioMedicine ; 93: 104590, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37300931

ABSTRACT

BACKGROUND: The phase 2b proof-of-concept Antibody Mediated Prevention (AMP) trials showed that VRC01, an anti-HIV-1 broadly neutralising antibody (bnAb), prevented acquisition of HIV-1 sensitive to VRC01. To inform future study design and dosing regimen selection of candidate bnAbs, we investigated the association of VRC01 serum concentration with HIV-1 acquisition using AMP trial data. METHODS: The case-control sample included 107 VRC01 recipients who acquired HIV-1 and 82 VRC01 recipients who remained without HIV-1 during the study. We measured VRC01 serum concentrations with a qualified pharmacokinetic (PK) Binding Antibody Multiplex Assay. We employed nonlinear mixed effects PK modelling to estimate daily-grid VRC01 concentrations. Cox regression models were used to assess the association of VRC01 concentration at exposure and baseline body weight, with the hazard of HIV-1 acquisition and prevention efficacy as a function of VRC01 concentration. We also compared fixed dosing vs. body weight-based dosing via simulations. FINDINGS: Estimated VRC01 concentrations in VRC01 recipients without HIV-1 were higher than those in VRC01 recipients who acquired HIV-1. Body weight was inversely associated with HIV-1 acquisition among both placebo and VRC01 recipients but did not modify the prevention efficacy of VRC01. VRC01 concentration was inversely correlated with HIV-1 acquisition, and positively correlated with prevention efficacy of VRC01. Simulation studies suggest that fixed dosing may be comparable to weight-based dosing in overall predicted prevention efficacy. INTERPRETATION: These findings suggest that bnAb serum concentration may be a useful marker for dosing regimen selection, and operationally efficient fixed dosing regimens could be considered for future trials of HIV-1 bnAbs. FUNDING: Was provided by the National Institutes of Health, National Institute of Allergy and Infectious Diseases (NIAID) (UM1 AI068614, to the HIV Vaccine Trials Network [HVTN]; UM1 AI068635, to the HVTN Statistical Data and Management Center [SDMC], Fred Hutchinson Cancer Center [FHCC]; 2R37 054165 to the FHCC; UM1 AI068618, to HVTN Laboratory Center, FHCC; UM1 AI068619, to the HPTN Leadership and Operations Center; UM1 AI068613, to the HIV Prevention Trials Network [HPTN] Laboratory Center; UM1 AI068617, to the HPTN SDMC; and P30 AI027757, to the Center for AIDS Research, Duke University (AI P30 AI064518) and University of Washington (P30 AI027757) Centers for AIDS Research; R37AI054165 from NIAID to the FHCC; and OPP1032144 CA-VIMC Bill & Melinda Gates Foundation.


Subject(s)
AIDS Vaccines , Acquired Immunodeficiency Syndrome , HIV Infections , HIV Seropositivity , HIV-1 , Humans , Broadly Neutralizing Antibodies , Antibodies, Neutralizing , Acquired Immunodeficiency Syndrome/drug therapy , HIV Seropositivity/drug therapy , HIV Antibodies
16.
J Int AIDS Soc ; 26(6): e26118, 2023 06.
Article in English | MEDLINE | ID: mdl-37363917

ABSTRACT

INTRODUCTION: Multiple antiretroviral agents have demonstrated efficacy for human immunodeficiency virus (HIV) pre-exposure prophylaxis (PrEP). As a result, clinical trials of novel agents have transitioned from placebo- to active-controlled designs; however, active-controlled trials do not provide an estimate of efficacy versus no use of PrEP. Counterfactual placebo comparisons using other data sources could be employed to provide this information. METHODS: We compared the active-controlled study (HPTN 084) of injectable cabotegravir (CAB-LA) versus daily oral emtricitabine/tenofovir disoproxil fumarate (FTC/TDF) among women from seven countries in Africa to three external, contemporaneous randomized HIV prevention trials from which we constructed counterfactual placebo estimates. We used direct standardization via analysis weights to achieve the same distribution of person-years between the external study and HPTN 084, across strata predictive of HIV risk (country and selected risk covariates). We estimated prevention efficacy against a counterfactual placebo to provide information on the use of CAB-LA and FTC/TDF compared to no intervention. We compared the counterfactual placebo findings for FTC/TDF to previous placebo-controlled trials, adjusted for observed adherence to daily pills. RESULTS: Distribution of age and baseline prevalence of gonorrhoea and chlamydia were similar among matched counterfactual placebo and observed HPTN 084 arms after standardization. Counterfactual estimates of CAB-LA versus placebo in all three settings showed a consistent risk reduction of 93%-94%, with lower bounds of the confidence intervals above 72%. Observed adherence (quantifiable tenofovir in plasma) in HPTN 084 was 54%-56%, and estimated efficacy of daily oral FTC/TDF against a counterfactual placebo was consistent with a predicted risk reduction of 39%-40% for this level of daily pill use. CONCLUSIONS: Counterfactual placebo rates of HIV acquisition derived from external trial data in similar locations and time can be used to support estimates of placebo-based efficacy of a novel HIV prevention agent. External trial data must be standardized to be representative of the clinical trial cohort testing the novel HIV prevention agent, accounting for confounders.


Subject(s)
Anti-HIV Agents , HIV Infections , Organophosphonates , Pre-Exposure Prophylaxis , Humans , Female , Emtricitabine/therapeutic use , Anti-HIV Agents/therapeutic use , HIV Infections/drug therapy , HIV Infections/prevention & control , Adenine , Organophosphonates/therapeutic use , Deoxycytidine/therapeutic use
17.
PLoS Pathog ; 19(6): e1011469, 2023 06.
Article in English | MEDLINE | ID: mdl-37384759

ABSTRACT

The VRC01 Antibody Mediated Prevention (AMP) efficacy trials conducted between 2016 and 2020 showed for the first time that passively administered broadly neutralizing antibodies (bnAbs) could prevent HIV-1 acquisition against bnAb-sensitive viruses. HIV-1 viruses isolated from AMP participants who acquired infection during the study in the sub-Saharan African (HVTN 703/HPTN 081) and the Americas/European (HVTN 704/HPTN 085) trials represent a panel of currently circulating strains of HIV-1 and offer a unique opportunity to investigate the sensitivity of the virus to broadly neutralizing antibodies (bnAbs) being considered for clinical development. Pseudoviruses were constructed using envelope sequences from 218 individuals. The majority of viruses identified were clade B and C; with clades A, D, F and G and recombinants AC and BF detected at lower frequencies. We tested eight bnAbs in clinical development (VRC01, VRC07-523LS, 3BNC117, CAP256.25, PGDM1400, PGT121, 10-1074 and 10E8v4) for neutralization against all AMP placebo viruses (n = 76). Compared to older clade C viruses (1998-2010), the HVTN703/HPTN081 clade C viruses showed increased resistance to VRC07-523LS and CAP256.25. At a concentration of 1µg/ml (IC80), predictive modeling identified the triple combination of V3/V2-glycan/CD4bs-targeting bnAbs (10-1074/PGDM1400/VRC07-523LS) as the best against clade C viruses and a combination of MPER/V3/CD4bs-targeting bnAbs (10E8v4/10-1074/VRC07-523LS) as the best against clade B viruses, due to low coverage of V2-glycan directed bnAbs against clade B viruses. Overall, the AMP placebo viruses represent a valuable resource for defining the sensitivity of contemporaneous circulating viral strains to bnAbs and highlight the need to update reference panels regularly. Our data also suggests that combining bnAbs in passive immunization trials would improve coverage of global viruses.


Subject(s)
HIV Infections , HIV Seropositivity , HIV-1 , Humans , HIV Antibodies , Broadly Neutralizing Antibodies , Antibodies, Neutralizing , Polysaccharides
18.
BMC Womens Health ; 23(1): 276, 2023 05 19.
Article in English | MEDLINE | ID: mdl-37208687

ABSTRACT

BACKGROUND: Trust is an important cornerstone of patient-provider communication. Accurate reporting of pre-exposure prophylaxis (PrEP) adherence is vital for providers to determine who needs adherence support, especially adolescent girls and young women (AGYW) disproportionately affected by newly diagnosed HIV. METHODS: This is a secondary analysis of the HPTN 082 open-label PrEP demonstration trial. From 2016-2018, 451 AGYW aged 16-25 years were enrolled in South Africa (Cape Town and Johannesburg) and Zimbabwe (Harare). PrEP was initiated by 427, and 354 (83%) had month three patient-reported adherence responses and intracellular tenofovir diphosphate (TFV-DP) measurements. The patient-reported adherence response to 'In the past month, how often did you take the tablet?' was dichotomized as 'high' if the response was every day or most days, and 'low' if some days or not many days or never. The biomarker marker evidence of adherence in dried blood spots was defined as 'high' if TFV-DP ≥ 700, and 'low' if < 350 fmol/punch. We used multinomial logistic regression to examine if trust in the PrEP provider was associated with concordance between patient-reported adherence and intracellular tenofovir-diphosphate (TFV-DP). RESULTS: AGYW who reported trust in their providers were almost four-fold (aOR 3.72, 95% CI 1.20-11.51) more likely to have concordant adherence (high self-reported adherence and high TFV-DP concentrations) compared to discordant non-adherence (high self-reported adherence and low TFV-DP concentrations). CONCLUSION: Education and training of providers to build trusting relationships with AGYW may lead to more accurate reporting of PrEP adherence. With accurate reporting, adequate support can be provided to bolster adherence. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02732730.


Subject(s)
Anti-HIV Agents , HIV Infections , Humans , Female , Adolescent , Anti-HIV Agents/therapeutic use , HIV Infections/prevention & control , HIV Infections/drug therapy , South Africa , Self Report , Zimbabwe , Trust , Medication Adherence
19.
Sex Transm Infect ; 99(7): 433-439, 2023 11.
Article in English | MEDLINE | ID: mdl-36889914

ABSTRACT

INTRODUCTION: We investigated the prevalence, incidence and factors associated with sexually transmitted infections (STIs) among young African women seeking HIV pre-exposure prophylaxis (PrEP). METHODS: HPTN 082 was a prospective, open-label PrEP study enrolling HIV-negative sexually active women aged 16-25 years in Cape Town and Johannesburg, South Africa, and Harare, Zimbabwe. Endocervical swabs from enrolment, months 6 and 12 were tested for Neisseria gonorrhoeae (GC) and Chlamydia trachomatis (CT) by nucleic acid amplification, and Trichomonas vaginalis (TV) by a rapid test. Intracellular tenofovir-diphosphate (TFV-DP) concentrations in dried blood spots were measured at months 6 and 12. Associations between risk characteristics and STI outcomes were assessed using Poisson regression. RESULTS: Of 451 enrolled participants, 55% had an STI detected at least once. CT incidence was 27.8 per 100 person-years (py) (95% CI 23.1, 33.2), GC incidence was 11.4 per 100 py (95% CI 8.5, 15.0) and TV incidence was 6.7 per 100 py (95% CI 4.5, 9.5). 66% of incident infections were diagnosed in women uninfected at baseline. Baseline cervical infection (GC or CT) risk was highest in Cape Town (relative risk (RR) 2.38, 95% CI 1.35, 4.19) and in those not living with family (RR 1.87, 95% 1.13, 3.08); condom use was protective (RR 0.67, 95% CI 0.45, 0.99). Incident CT was associated with baseline CT (RR 2.01; 95% CI 1.28, 3.15) and increasing depression score (RR 1.05; 95% CI 1.01, 1.09). Incident GC was higher in Cape Town (RR 2.40; 95% CI 1.18, 4.90) and in participants with high PrEP adherence (TFV-DP concentrations ≥700 fmol/punch) (RR 2.04 95% CI 1.02, 4.08). CONCLUSION: Adolescent girls and young women seeking PrEP have a high prevalence and incidence of curable STIs. Alternatives to syndromic management for diagnosis and treatment are needed to reduce the burden of STIs in this population. TRIAL REGISTRATION NUMBER: NCT02732730.


Subject(s)
Gonorrhea , HIV Infections , Pre-Exposure Prophylaxis , Sexually Transmitted Diseases , Trichomonas vaginalis , Adolescent , Female , Humans , Gonorrhea/diagnosis , HIV Infections/epidemiology , HIV Infections/prevention & control , HIV Infections/drug therapy , South Africa/epidemiology , Zimbabwe/epidemiology , Incidence , Prospective Studies , Prevalence , Sexually Transmitted Diseases/epidemiology , Chlamydia trachomatis/genetics
20.
PLOS Glob Public Health ; 3(2): e0000796, 2023.
Article in English | MEDLINE | ID: mdl-36963004

ABSTRACT

Safer conception services are needed to minimize HIV transmission among HIV sero-different couples desiring pregnancy. Few studies have evaluated the choices couples make when offered multiple safer conception methods or real-world method acceptability and effectiveness. We piloted a comprehensive safer conception program (Clintrials.gov identifier: NCT03049176) for HIV sero-different couples planning pregnancy in Zimbabwe to measure feasibility, method uptake, acceptability, pregnancy outcome, and HIV transmission. This study was not designed to compare rates of HIV transmission by safer conception method choice but rather to understand choices couples make when seeking to minimize risk of HIV transmission and maximize likelihood of pregnancy. Couples in this prospective, non-randomized study were given a choice of one or more currently available safer conception methods: antiretroviral therapy (ART) with monthly viral load (VL) monitoring for the HIV-positive partner (ART/VL), pre-exposure prophylaxis (PrEP) for the HIV-negative partner, vaginal insemination (VI) for couples with an HIV-positive woman, and semen washing (SW) for couples with an HIV-positive man. Couples were followed monthly for up to 12 months of pregnancy attempts, quarterly during pregnancy, and 12 weeks post-partum. At each visit, data on method use, urine for pregnancy testing, and blood for HIV antibody testing, or viral load if HIV-positive, were obtained. Infants born to HIV-positive women were tested for HIV at 6 and 12 weeks. Between March 2017 and June 2019, 46 individuals from 23 HIV sero-different partnerships were enrolled and followed. At enrollment, all couples chose ART/VL, and all couples chose at least one additional method; 74% chose PrEP, 36% chose SW, and 25% chose VI. During pre-pregnancy follow-up visits, three couples discontinued SW, and one couple discontinued VI; all four of these couples opted for ART/VL plus PrEP. Satisfaction with safer conception methods was high among those who chose ART/VL and PrEP. Twelve couples achieved pregnancy. There were no cases of HIV transmission to partners, and no infants tested positive for HIV. This safer conception program is feasible and acceptable, allowing sero-different couples to safely achieve pregnancy. Sero-different couples in Zimbabwe seek a combination of HIV prevention methods, particularly ART/VL plus PrEP. Trial Registration: Clintrials.gov, NCT03049176.

SELECTION OF CITATIONS
SEARCH DETAIL
...