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result(s) for
"Sawe, Fred"
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Timing of Antiretroviral Therapy for HIV-1 Infection and Tuberculosis
by
Havlir, Diane V
,
Sawe, Fred
,
Kendall, Michelle A
in
Acquired immune deficiency syndrome
,
Adult
,
AIDS
2011
In this international study involving 809 patients with HIV and TB coinfection, earlier therapy for both infections, versus waiting 8 to 12 weeks to initiate antiretrovirals after anti-TB therapy, was beneficial in patients with a low CD4+ T-cell count (<50 per cubic millimeter).
The treatment of patients with tuberculosis and newly identified infection with human immunodeficiency virus type 1 (HIV-1) is one of the most challenging aspects of HIV medicine. Antiretroviral therapy (ART) must be started during treatment for tuberculosis,
1
,
2
yet starting ART very early in the course of tuberculosis therapy increases the pill burden, the potential drug toxicity, and the risk of tuberculosis-associated immune reconstitution inflammatory syndrome (IRIS).
3
,
4
For these reasons, programs, providers, and patients are reluctant to initiate ART during the intensive 8-week induction phase of tuberculosis therapy, when the pill burden and toxicity of tuberculosis medications are greatest. . . .
Journal Article
Pregnancy outcomes among HIV-infected women who conceived on antiretroviral therapy
by
Nielsen-Saines, Karin
,
Stringer, Elizabeth M.
,
Sawe, Fred
in
Abortion
,
Acquired immune deficiency syndrome
,
Adult
2018
As antiretroviral therapy (ART) expands in resource-limited settings, understanding the impact of ART on pregnancy outcomes is critical. We analyzed women who became pregnant on ART while enrolled in a clinical trial (HPTN 052, ACTG A5208, and ACTG A5175); the majority of women were from Africa, with a median age of 29 years. Eligible women were on ART at conception and had a documented date of a last menstrual period and a pregnancy outcome. The primary outcome was non-live birth (stillbirth; spontaneous abortion; elective termination; or ectopic pregnancy) versus live birth. Preterm birth (<37 weeks completed gestation) was a secondary outcome. We used Cox proportional hazards regression models with time-varying covariates. 359 women became pregnant, of whom 253 (70%) met inclusion criteria: 127 (50%) were on NNRTI-based ART, 118 (47%) on PI-based ART, and 8 (3%) on 3-NRTIs at conception. There were 160 (63%) live births (76 term and 84 preterm), 11 (4%) stillbirths, 51 (20%) spontaneous abortions, 28 (11%) elective terminations, and 3 (1%) ectopic pregnancies. In multivariable analysis adjusted for region, parent study, and pre-pregnancy ART class, only older age was associated with increased hazard of preterm birth [HR: 2.49 for age 25-30 years; 95% CI: 1.18-5.26; p = 0.017]. Women conceiving on ART had high rates of preterm birth and other adverse pregnancy outcomes. Despite the benefits of ART, studies designed to investigate the effects of preconception ART on pregnancy outcomes are needed.
Journal Article
Prospective Study of Acute HIV-1 Infection in Adults in East Africa and Thailand
2016
Acute human immunodeficiency virus type 1 (HIV-1) infection is a major contributor to transmission of HIV-1. An understanding of acute HIV-1 infection may be important in the development of treatment strategies to eradicate HIV-1 or achieve a functional cure.
We performed twice-weekly qualitative plasma HIV-1 RNA nucleic acid testing in 2276 volunteers who were at high risk for HIV-1 infection. For participants in whom acute HIV-1 infection was detected, clinical observations, quantitative measurements of plasma HIV-1 RNA levels (to assess viremia) and HIV antibodies, and results of immunophenotyping of lymphocytes were obtained twice weekly.
Fifty of 112 volunteers with acute HIV-1 infection had two or more blood samples collected before HIV-1 antibodies were detected. The median peak viremia (6.7 log10 copies per milliliter) occurred 13 days after the first sample showed reactivity on nucleic acid testing. Reactivity on an enzyme immunoassay occurred at a median of 14 days. The nadir of viremia (4.3 log10 copies per milliliter) occurred at a median of 31 days and was nearly equivalent to the viral-load set point, the steady-state viremia that persists durably after resolution of acute viremia (median plasma HIV-1 RNA level, 4.4 log10 copies per milliliter). The peak viremia and downslope were correlated with the viral-load set point. Clinical manifestations of acute HIV-1 infection were most common just before and at the time of peak viremia. A median of one symptom of acute HIV-1 infection was recorded at a median of two study visits, and a median of one sign of acute HIV-1 infection was recorded at a median of three visits.
The viral-load set point occurred at a median of 31 days after the first detection of plasma viremia and correlated with peak viremia. Few symptoms and signs were observed during acute HIV-1 infection, and they were most common before peak viremia. (Funded by the Department of Defense and the National Institute of Allergy and Infectious Diseases.).
Journal Article
Molecular dating and viral load growth rates suggested that the eclipse phase lasted about a week in HIV-1 infected adults in East Africa and Thailand
2020
Most HIV-1 infected individuals do not know their infection dates. Precise infection timing is crucial information for studies that document transmission networks or drug levels at infection. To improve infection timing, we used the prospective RV217 cohort where the window when plasma viremia becomes detectable is narrow: the last negative visit occurred a median of four days before the first detectable HIV-1 viremia with an RNA test, referred below as diagnosis. We sequenced 1,280 HIV-1 genomes from 39 participants at a median of 4, 32 and 170 days post-diagnosis. HIV-1 infections were dated by using sequence-based methods and a viral load regression method. Bayesian coalescent and viral load regression estimated that infections occurred a median of 6 days prior to diagnosis (IQR: 9-3 and 11-4 days prior, respectively). Poisson-Fitter, which analyzes the distribution of hamming distances among sequences, estimated a median of 7 days prior to diagnosis (IQR: 15-4 days) based on sequences sampled 4 days post-diagnosis, but it did not yield plausible results using sequences sampled at 32 days. Fourteen participants reported a high-risk exposure event at a median of 8 days prior to diagnosis (IQR: 12 to 6 days prior). These different methods concurred that HIV-1 infection occurred about a week before detectable viremia, corresponding to 20 days (IQR: 34-15 days) before peak viral load. Together, our methods comparison helps define a framework for future dating studies in early HIV-1 infection.
Journal Article
Pre‐exposure prophylaxis implementation gaps among people vulnerable to HIV acquisition: a cross‐sectional analysis in two communities in western Kenya, 2021–2023
2024
Introduction
Despite the increasing availability of prevention tools like pre‐exposure prophylaxis (PrEP), HIV incidence remains disproportionately high in sub‐Saharan Africa. We examined PrEP awareness, uptake and persistence among participants enrolling into an HIV incidence cohort in Kenya.
Methods
We used cross‐sectional enrolment data from the Multinational Observational Cohort of HIV and other Infections (MOCHI) in Homa Bay and Kericho, Kenya. The cohort recruited individuals aged 14–55 years with a recent history of sexually transmitted infection, transactional sex, condomless sex and/or injection drug use. Participants completed questionnaires on PrEP, demographics and sexual behaviours. We used multivariable robust Poisson regression to estimate adjusted prevalence ratios (aPRs) and 95% confidence intervals (CIs) for associations with never hearing of PrEP, never taking PrEP and ever stopping PrEP.
Results
Between 12/2021 and 5/2023, 399 participants attempted the PrEP questionnaire, of whom 316 (79.2%) were female and median age was 22 years (interquartile range 19–24); 316 of 390 participants (81.0%) engaged in sex work or transactional sex. Of 396 participants who responded to the question, 120 (30.3%) had never heard of PrEP. Of 275 participants who had heard of PrEP, 206 (74.9%) had never taken it. Of 69 participants who had ever taken PrEP, 50 (72.5%) stopped it at some time prior to enrolment. Participants aged 15–19 years more often reported never taking PrEP compared with those 25–36 years (aPR 1.31, 95% CI: 1.06–1.61). Participants who knew someone who took PrEP less often reported never hearing about PrEP (aPR 0.10, 95% CI: 0.04–0.23) and never taking PrEP (aPR: 0.69, 95% CI: 0.60–0.80). Stopping PrEP was more common among participants with a weekly household income ≤1000 versus >1000 Kenyan shillings (aPR 1.40, 95% CI: 1.02–1.93) and those using alcohol/drugs before sex (aPR 1.53, 95% CI: 1.03–2.26). Stopping PrEP was less common among those engaging in sex work or transactional sex (aPR 0.6, 95% CI: 0.40–0.92).
Conclusions
We identified substantial gaps in PrEP awareness, uptake and persistence, which were associated with potential system‐ and individual‐level risk factors. Our analyses also highlight the importance of increasing PrEP engagement among individuals who do not know others taking PrEP.
Journal Article
A Phase 1/2 Study of a Multiclade HIV-1 DNA Plasmid Prime and Recombinant Adenovirus Serotype 5 Boost Vaccine in HIV-Uninfected East Africans (RV 172)
by
Sawe, Fred
,
Dally, Len
,
Birx, Deborah L.
in
Adenoviridae - genetics
,
Adenoviridae - immunology
,
Adenovirus
2010
Background. Human immunodeficiency virus (HIV) vaccine development remains a global priority. We describe the safety and immunogenicity of a multiclade DNA vaccine prime with a replication-defective recombinant adenovirus serotype 5 (rAd5) boost. Methods. The vaccine is a 6-plasmid mixture encoding HIV envelope (env) subtypes A, B, and C and subtype B gag, pol, and nef, and an rAd5 expressing identical genes, with the exception of nef. Three hundred and twentyfour participants were randomized to receive placebo (n = 138), a single dose of rAd5 at 1010 (n = 24) or 1011 particle units (n = 24), or DNA at 0, 1, and 2 months, followed by rAd5 at either 1010 (n = 114) or 1011 particle units (n = 24) boosting at 6 months. Participants were followed up for 24 weeks after the final vaccination. Results. The vaccine was safe and well tolerated. HIV-specific T cell responses were detected in 63% of vaccinees. Titers of preexisting Ad5 neutralizing antibody did not affect the frequency and magnitude of T cell responses in prime-boost recipients but did affect the response rates in participants that received rAd5 alone (P = .037). Conclusion. The DNA/rAd5 vaccination regimen was safe and induced HIV type 1 multi-clade T cell responses, which were not significantly affected by titers of preexisting rAd5 neutralizing antibody. Trial Registration. ClinicalTrials.gov identifier: NCT00123968.
Journal Article
Nevirapine- Versus Lopinavir/Ritonavir-Based Initial Therapy for HIV-1 Infection among Women in Africa: A Randomized Trial
by
Alston-Smith, Beverly
,
Sawe, Fred
,
Hosseinipour, Mina
in
Adult
,
Africa
,
Anti-HIV Agents - adverse effects
2012
Nevirapine (NVP) is widely used in antiretroviral treatment (ART) of HIV-1 globally. The primary objective of the AA5208/OCTANE trial was to compare the efficacy of NVP-based versus lopinavir/ritonavir (LPV/r)-based initial ART.
In seven African countries (Botswana, Kenya, Malawi, South Africa, Uganda, Zambia, and Zimbabwe), 500 antiretroviral-naïve HIV-infected women with CD4<200 cells/mm(3) were enrolled into a two-arm randomized trial to initiate open-label ART with tenofovir (TDF)/emtricitabine (FTC) once/day plus either NVP (n = 249) or LPV/r (n = 251) twice/day, and followed for ≥48 weeks. The primary endpoint was time from randomization to death or confirmed virologic failure ([VF]) (plasma HIV RNA<1 log(10) below baseline 12 weeks after treatment initiation, or ≥400 copies/ml at or after 24 weeks), with comparison between treatments based on hazard ratios (HRs) in intention-to-treat analysis. Equivalence of randomized treatments was defined as finding the 95% CI for HR for virological failure or death in the range 0.5 to 2.0. Baseline characteristics were (median): age = 34 years, CD4 = 121 cells/mm(3), HIV RNA = 5.2 log(10)copies/ml. Median follow-up = 118 weeks; 29 (6%) women were lost to follow-up. 42 women (37 VFs, five deaths; 17%) in the NVP and 50 (43 VFs, seven deaths; 20%) in the LPV/r arm reached the primary endpoint (HR 0.85, 95% CI 0.56-1.29). During initial assigned treatment, 14% and 16% of women receiving NVP and LPV/r experienced grade 3/4 signs/symptoms and 26% and 22% experienced grade 3/4 laboratory abnormalities. However, 35 (14%) women discontinued NVP because of adverse events, most in the first 8 weeks, versus none for LPV/r (p<0.001). VF, death, or permanent treatment discontinuation occurred in 80 (32%) of NVP and 54 (22%) of LPV/r arms (HR = 1.7, 95% CI 1.2-2.4), with the difference primarily due to more treatment discontinuation in the NVP arm. 13 (45%) of 29 women tested in the NVP versus six (15%) of 40 in the LPV/r arm had any drug resistance mutation at time of VF.
Initial ART with NVP+TDF/FTC demonstrated equivalent virologic efficacy but higher rates of treatment discontinuation and new drug resistance compared with LPV/r+TDF/FTC in antiretroviral-naïve women with CD4<200 cells/mm(3).
ClinicalTrials.gov NCT00089505.
Journal Article
Factors influencing estimates of HIV-1 infection timing using BEAST
by
Li, Yifan
,
Nitayaphan, Sorachai
,
Ahani, Bahar
in
Biology and Life Sciences
,
Computer and Information Sciences
,
Eigenvalues
2021
While large datasets of HIV-1 sequences are increasingly being generated, many studies rely on a single gene or fragment of the genome and few comparative studies across genes have been done. We performed genome-based and gene-specific Bayesian phylogenetic analyses to investigate how certain factors impact estimates of the infection dates in an acute HIV-1 infection cohort, RV217. In this cohort, HIV-1 diagnosis corresponded to the first RNA positive test and occurred a median of four days after the last negative test, allowing us to compare timing estimates using BEAST to a narrow window of infection. We analyzed HIV-1 sequences sampled one week, one month and six months after HIV-1 diagnosis in 39 individuals. We found that shared diversity and temporal signal was limited in acute infection, and insufficient to allow timing inferences in the shortest HIV-1 genes, thus dated phylogenies were primarily analyzed for
env
,
gag
,
pol
and near full-length genomes. There was no one best-fitting model across participants and genes, though relaxed molecular clocks (73% of best-fitting models) and the Bayesian skyline (49%) tended to be favored. For infections with single founders, the infection date was estimated to be around one week pre-diagnosis for
env
(IQR: 3–9 days) and
gag
(IQR: 5–9 days), whilst the genome placed it at a median of 10 days (IQR: 4–19). Multiply-founded infections proved problematic to date. Our ability to compare timing inferences to precise estimates of HIV-1 infection (within a week) highlights that molecular dating methods can be applied to within-host datasets from early infection. Nonetheless, our results also suggest caution when using uniform clock and population models or short genes with limited information content.
Journal Article
Combining Viral Genetics and Statistical Modeling to Improve HIV-1 Time-of-Infection Estimation towards Enhanced Vaccine Efficacy Assessment
by
Eller, Leigh
,
Sawe, Fred
,
Nitayaphan, Sorachai
in
Accuracy
,
acute and early HIV-1 infection
,
AIDS Vaccines
2019
Knowledge of the time of HIV-1 infection and the multiplicity of viruses that establish HIV-1 infection is crucial for the in-depth analysis of clinical prevention efficacy trial outcomes. Better estimation methods would improve the ability to characterize immunological and genetic sequence correlates of efficacy within preventive efficacy trials of HIV-1 vaccines and monoclonal antibodies. We developed new methods for infection timing and multiplicity estimation using maximum likelihood estimators that shift and scale (calibrate) estimates by fitting true infection times and founder virus multiplicities to a linear regression model with independent variables defined by data on HIV-1 sequences, viral load, diagnostics, and sequence alignment statistics. Using Poisson models of measured mutation counts and phylogenetic trees, we analyzed longitudinal HIV-1 sequence data together with diagnostic and viral load data from the RV217 and CAPRISA 002 acute HIV-1 infection cohort studies. We used leave-one-out cross validation to evaluate the prediction error of these calibrated estimators versus that of existing estimators and found that both infection time and founder multiplicity can be estimated with improved accuracy and precision by calibration. Calibration considerably improved all estimators of time since HIV-1 infection, in terms of reducing bias to near zero and reducing root mean squared error (RMSE) to 5–10 days for sequences collected 1–2 months after infection. The calibration of multiplicity assessments yielded strong improvements with accurate predictions (ROC-AUC above 0.85) in all cases. These results have not yet been validated on external data, and the best-fitting models are likely to be less robust than simpler models to variation in sequencing conditions. For all evaluated models, these results demonstrate the value of calibration for improved estimation of founder multiplicity and of time since HIV-1 infection.
Journal Article
The Frequency of Malaria Is Similar among Women Receiving either Lopinavir/Ritonavir or Nevirapine-based Antiretroviral Treatment
by
Shaffer, Doug
,
Sawe, Fred
,
Currier, Judith S.
in
Antigens
,
Antimalarial activity
,
Antimalarial agents
2012
HIV protease inhibitors (PIs) show antimalarial activity in vitro and in animals. Whether this translates into a clinical benefit in HIV-infected patients residing in malaria-endemic regions is unknown. We studied the incidence of malaria, as defined by blood smear positivity or a positive Plasmodium falciparum histidine-rich protein 2 antigen test, among 444 HIV-infected women initiating antiretroviral treatment (ART) in the OCTANE trial (A5208; ClinicalTrials.gov: NCT00089505). Participants were randomized to treatment with PI-containing vs. PI-sparing ART, and were followed prospectively for ≥48 weeks; 73% also received cotrimoxazole prophylaxis. PI-containing treatment was not associated with protection against malaria in this study population.
Journal Article