Browsing by Department "Desmond Tutu HIV Centre"
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- ItemOpen AccessAdjusting mortality for loss to follow-up: analysis of five ART programmes in sub-Saharan Africa(Public Library of Science, 2010) Brinkhof, Martin W G; Spycher, Ben D; Yiannoutsos, Constantin; Weigel, Ralf; Wood, Robin; Messou, Eugène; Boulle, Andrew; Egger, Matthias; Sterne, Jonathan A C; (IeDEA), for the International epidemiological Database to Evaluate AIDSBACKGROUND: Evaluation of antiretroviral treatment (ART) programmes in sub-Saharan Africa is difficult because many patients are lost to follow-up. Outcomes in these patients are generally unknown but studies tracing patients have shown mortality to be high. We adjusted programme-level mortality in the first year of antiretroviral treatment (ART) for excess mortality in patients lost to follow-up. Methods and FINDINGS: Treatment-naïve patients starting combination ART in five programmes in Côte d'Ivoire, Kenya, Malawi and South Africa were eligible. Patients whose last visit was at least nine months before the closure of the database were considered lost to follow-up. We filled missing survival times in these patients by multiple imputation, using estimates of mortality from studies that traced patients lost to follow-up. Data were analyzed using Weibull models, adjusting for age, sex, ART regimen, CD4 cell count, clinical stage and treatment programme. A total of 15,915 HIV-infected patients (median CD4 cell count 110 cells/µL, median age 35 years, 68% female) were included; 1,001 (6.3%) were known to have died and 1,285 (14.3%) were lost to follow-up in the first year of ART. Crude estimates of mortality at one year ranged from 5.7% (95% CI 4.9-6.5%) to 10.9% (9.6-12.4%) across the five programmes. Estimated mortality hazard ratios comparing patients lost to follow-up with those remaining in care ranged from 6 to 23. Adjusted estimates based on these hazard ratios ranged from 10.2% (8.9-11.6%) to 16.9% (15.0-19.1%), with relative increases in mortality ranging from 27% to 73% across programmes. CONCLUSIONS: Naïve survival analysis ignoring excess mortality in patients lost to follow-up may greatly underestimate overall mortality, and bias ART programme evaluations. Adjusted mortality estimates can be obtained based on excess mortality rates in patients lost to follow-up.
- ItemOpen AccessAGILE: a seamless phase I/IIa platform for the rapid evaluation of candidates for COVID-19 treatment: an update to the structured summary of a study protocol for a randomised platform trial letter(2021-07-26) Griffiths, Gareth O; FitzGerald, Richard; Jaki, Thomas; Corkhill, Andrea; Reynolds, Helen; Ewings, Sean; Condie, Susannah; Tilt, Emma; Johnson, Lucy; Radford, Mike; Simpson, Catherine; Saunders, Geoffrey; Yeats, Sara; Mozgunov, Pavel; Tansley-Hancock, Olana; Martin, Karen; Downs, Nichola; Eberhart, Izabela; Martin, Jonathan W B; Goncalves, Cristiana; Song, Anna; Fletcher, Tom; Byrne, Kelly; Lalloo, David G; Owen, Andrew; Jacobs, Michael; Walker, Lauren; Lyon, Rebecca; Woods, Christie; Gibney, Jennifer; Chiong, Justin; Chandiwana, Nomathemba; Jacob, Shevin; Lamorde, Mohammed; Orrell, Catherine; Pirmohamed, Munir; Khoo, SayeBackground There is an urgent unmet clinical need for the identification of novel therapeutics for the treatment of COVID-19. A number of COVID-19 late phase trial platforms have been developed to investigate (often repurposed) drugs both in the UK and globally (e.g. RECOVERY led by the University of Oxford and SOLIDARITY led by WHO). There is a pressing need to investigate novel candidates within early phase trial platforms, from which promising candidates can feed into established later phase platforms. AGILE grew from a UK-wide collaboration to undertake early stage clinical evaluation of candidates for SARS-CoV-2 infection to accelerate national and global healthcare interventions. Methods/design AGILE is a seamless phase I/IIa platform study to establish the optimum dose, determine the activity and safety of each candidate and recommend whether it should be evaluated further. Each candidate is evaluated in its own trial, either as an open label single arm healthy volunteer study or in patients, randomising between candidate and control usually in a 2:1 allocation in favour of the candidate. Each dose is assessed sequentially for safety usually in cohorts of 6 patients. Once a phase II dose has been identified, efficacy is assessed by seamlessly expanding into a larger cohort. AGILE is completely flexible in that the core design in the master protocol can be adapted for each candidate based on prior knowledge of the candidate (i.e. population, primary endpoint and sample size can be amended). This information is detailed in each candidate specific trial protocol of the master protocol. Discussion Few approved treatments for COVID-19 are available such as dexamethasone, remdesivir and tocilizumab in hospitalised patients. The AGILE platform aims to rapidly identify new efficacious and safe treatments to help end the current global COVID-19 pandemic. We currently have three candidate specific trials within this platform study that are open to recruitment. Trial registration EudraCT Number: 2020-001860-27 14 March 2020 ClinicalTrials.gov Identifier: NCT04746183 19 February 2021 ISRCTN reference: 27106947
- ItemOpen AccessAntiretroviral therapy for prevention of tuberculosis in adults with HIV: a systematic review and meta-analysis(Public Library of Science, 2012) Suthar, Amitabh B; Lawn, Stephen D; Del Amo, Julia; Getahun, Haileyesus; Dye, Christopher; Sculier, Delphine; Sterling, Timothy R; Chaisson, Richard E; Williams, Brian G; Harries, Anthony DIn a systematic review and meta-analysis, Amitabh Suthar and colleagues investigate the association between antiretroviral therapy and the reduction in the incidence of tuberculosis in adults with HIV infection.
- ItemOpen AccessAntiretroviral treatment cohort analysis using time-updated CD4 counts: assessment of bias with different analytic methods(Public Library of Science, 2011) Kranzer, Katharina; Lewis, James J; White, Richard G; Glynn, Judith R; Lawn, Stephen D; Middelkoop, Keren; Bekker, Linda-Gail; Wood, RobinBACKGROUND: Survival analysis using time-updated CD4+ counts during antiretroviral therapy is frequently employed to determine risk of clinical events. The time-point when the CD4+ count is assumed to change potentially biases effect estimates but methods used to estimate this are infrequently reported. METHODS: This study examined the effect of three different estimation methods: assuming i) a constant CD4+ count from date of measurement until the date of next measurement, ii) a constant CD4+ count from the midpoint of the preceding interval until the midpoint of the subsequent interval and iii) a linear interpolation between consecutive CD4+ measurements to provide additional midpoint measurements. Person-time, tuberculosis rates and hazard ratios by CD4+ stratum were compared using all available CD4+ counts (measurement frequency 1-3 months) and 6 monthly measurements from a clinical cohort. Simulated data were used to compare the extent of bias introduced by these methods. RESULTS: The midpoint method gave the closest fit to person-time spent with low CD4+ counts and for hazard ratios for outcomes both in the clinical dataset and the simulated data. CONCLUSION: The midpoint method presents a simple option to reduce bias in time-updated CD4+ analysis, particularly at low CD4 cell counts and rapidly increasing counts after ART initiation.
- ItemOpen AccessAsking the right questions: developing evidence-based strategies for treating HIV in women and children(BioMed Central Ltd, 2011) Karim, Quarraisha; Banegura, Anchilla; Cahn, Pedro; Christie, Celia; Dintruff, Robert; Distel, Manuel; Hankins, Catherine; Hellmann, Nicholas; Katabira, Elly; Lehrman, Sandra; Montaner, Julio; Purdon, Scott; Rooney, James; Wood, Robin; Heidari, ShiriIn July 2010, the World Health Organization (WHO) issued formal revisions of its guidelines on the use of highly active antiretroviral therapy for HIV. The new guidelines greatly expand eligibility for treatment of adults and children, as well as for pregnant women seeking prophylaxis for vertical HIV transmission. WHO's new recommendations bring the guidelines closer to practices in developed countries, and its shift to earlier treatment alone will increase the number of treatment-eligible people by 50% or more.Scaling up access to HIV treatment is revealing important gaps in our understanding of how best to provide for all those in need. This knowledge gap is especially significant in developing countries, where women and children comprise a majority of those living with HIV infection. Given the magnitude and significance of these populations, the International AIDS Society, through its Industry Liaison Forum, prioritized HIV treatment and prophylaxis of women and children. In March 2010, the International AIDS Society and 15 partners launched a Consensus Statement outlining priority areas in which a relative lack of knowledge impedes delivery of optimal prevention of mother to child transmission (PMTCT) and treatment to women and children.The Consensus Statement, "Asking the Right Questions: Advancing an HIV Research Agenda for Women and Children", makes a special appeal for a more gender-sensitive approach to HIV research at all stages, from conception to design and implementation. It particularly emphasizes research to enhance the understanding of sex-based differences and paediatric needs in treatment uptake and response. In addition to clinical issues, the statement focuses on programmatic research that facilitates access and adherence to antiretroviral regimens. Better coordination of HIV management with sexual and reproductive healthcare delivery is one such approach.We discuss here our knowledge gaps concerning effective, safe PMTCT and treatment for women and children in light of the expansion envisioned by WHO's revised guidelines. The guideline's new goals present an opportunity for advancing the women and children's agenda outlined in the Consensus Statement.
- ItemOpen AccessBlood neutrophil counts in HIV-infected patients with pulmonary tuberculosis: association with sputum mycobacterial load(Public Library of Science, 2013) Kerkhoff, Andrew D; Wood, Robin; Lowe, David M; Vogt, Monica; Lawn, Stephen DBACKGROUND: Increasing evidence suggests that neutrophils play a role in the host response to Mycobacterium tuberculosis . We determined whether neutrophil counts in peripheral blood are associated with tuberculosis (TB) and with mycobacterial load in sputum in HIV-infected patients. METHODOLOGY/PRINCIPAL FINDINGS: Adults enrolling in an antiretroviral treatment (ART) clinic in a Cape Town township were screened for TB regardless of symptoms. Paired sputum samples were examined using liquid culture, fluorescence microscopy, and the Xpert MTB/RIF assay. Absolute neutrophil counts (ANC) were measured in blood samples. Of 602 HIV-infected patients screened, 523 produced one or more sputum samples and had complete results available for analysis. Among these 523 patients, the median CD4 count was 169×10 9 /L (IQR, 96-232) and median ANC was 2.6×10 9 /L (IQR, 1.9-3.6). Culture-positive pulmonary tuberculosis was diagnosed in 89 patients. Patients with TB had a median ANC of 3.4×10 9 /L (IQR, 2.4-5.1) compared to 2.5×10 9 /L (IQR, 1.8-3.4) among those who were culture negative (p<0.0001). In multivariable analyses, having pulmonary TB was associated with an adjusted risk ratio (aRR) of 2.6 (95%CI, 1.5-4.5) for having an ANC level that exceeded the median value (ANC ≥2.6×10 9 /L; p = 0.0006) and an aRR of 6.8 (95%CI, 2.3-20.4) for having neutrophilia defined by a neutrophil count exceeding the upper limit of the normal range (ANC >7.5×10 9 /L; p = 0.0005). Patients were then classified into four mutually exclusive groups with increasing sputum mycobacterial load as defined by the results of culture, Xpert MTB/RIF and sputum smear microscopy. Multivariable analyses demonstrated that increasing sputum mycobacterial load was positively associated with blood ANC ≥2.6×10 9 /L and with neutrophilia. Conclusions/Significance Increased blood neutrophil counts were independently associated with pulmonary TB and sputum mycobacterial burden in this HIV-infected patient group. This observation supports the growing body of literature regarding the potential role for neutrophils in the host response to TB.
- ItemOpen AccessBroadly neutralizing antibody responses in a large longitudinal sub-Saharan HIV primary infection cohort(Public Library of Science, 2016) Landais, Elise; Huang, Xiayu; Havenar-Daughton, Colin; Murrell, Ben; Price, Matt A; Wickramasinghe, Lalinda; Ramos, Alejandra; Bian, Charoan B; Simek, Melissa; Allen, Susan; Karita, Etienne; Kilembe, William; Lakhi, Shabir; Inambao, Mubiana; Kamali, Anatoli; Sanders, Eduard J; Anzala, Omu; Edward, Vinodh; Bekker, Linda-Gail; Tang, Jianming; Gilmour, Jill; Kosakovsky-Pond, Sergei L; Phung, Pham; Wrin, Terri; Crotty, Shane; Godzik, Adam; Poignard, PascalAuthor Summary Understanding how HIV-1-broadly neutralizing antibodies (bnAbs) develop during natural infection is essential to the design of an efficient HIV vaccine. We studied kinetics and correlates of neutralization breadth in a large sub-Saharan African longitudinal cohort of 439 participants with primary HIV-1 infection. Broadly nAb responses developed in 15% of individuals, on average three years after infection. Broad neutralization was associated with high viral load, low CD4+ T cell counts, virus subtype C infection and HLA*A3(-) genotype. A correlation with high overall plasma IgG levels and anti-Env binding titers was also found. Specificity mapping of the bnAb responses showed that glycan-dependent epitopes, in particular the N332 region, were most commonly targeted, in contrast to other bnAb epitopes, suggesting that the HIV Env N332-glycan epitope region may be a favorable target for vaccine design.
- ItemOpen AccessBurden of new and recurrent tuberculosis in a major South African city stratified by age and HIV-status(Public Library of Science, 2011) Wood, Robin; Lawn, Stephen D; Caldwell, Judy; Kaplan, Richard; Middelkoop, Keren; Bekker, Linda-GailAim: To describe the burden of tuberculosis (TB) in Cape Town by calculating TB incidence rates stratified by age and HIV-status, assessing the contribution of retreatment disease and estimating the cumulative lifetime TB risk in HIV-negative individuals. METHODS: Details of TB cases were abstracted from the 2009 electronic TB register. Population denominators were estimated from census data and actuarial estimates of HIV prevalence, allowing calculation of age-specific and HIV-stratified TB notification rates. RESULTS: The 2009 mid-year population was 3,443,010 (3,241,508 HIV-negative and 201,502 HIV-positive individuals). There were 29,478 newly notified TB cases of which 56% were laboratory confirmed. HIV status was recorded for 87% of cases and of those with known HIV-status 49% were HIV-negative and 51% were positive. Discrete peaks in the incidence of non-HIV-associated TB occurred at three ages: 511/100,000 at 0-4 years of age, 553/100,000 at 20-24 years and 628/100,000 at 45-49 years with 1.5%, 19% and 45% being due to retreatment TB, respectively. Only 15.5% of recurrent cases had a history of TB treatment failure or default. The cumulative lifetime risks in the HIV-negative population of all new TB episodes and new smear-positive TB episodes were 24% and 12%, respectively; the lifetime risk of retreatment disease was 9%. The HIV-positive notification rate was 6,567/100,000 (HIV-associated TB rate ratio = 17). Although retreatment cases comprised 30% of the HIV-associated TB burden, 88% of these patients had no history of prior treatment failure or default. CONCLUSIONS: The annual burden of TB in this city is huge. TB in the HIV-negative population contributed almost half of the overall disease burden and cumulative lifetime risks were similar to those reported in the pre-chemotherapy era. Retreatment TB contributed significantly to both HIV-associated and non-HIV-associated TB but infrequently followed prior inadequate treatment. This likely reflects ongoing TB transmission to both HIV-negative and positive individuals.
- ItemOpen AccessCD4 cell count recovery among HIV-infected patients with very advanced immunodeficiency commencing antiretroviral treatment in sub-Saharan Africa(BioMed Central Ltd, 2006) Lawn, Stephen; Myer, Landon; Bekker, Linda-Gail; Wood, RobinBACKGROUND:Patients accessing antiretroviral treatment (ART) programmes in sub-Saharan Africa frequently have very advanced immunodeficiency. Previous data suggest that such patients may have diminished capacity for CD4 cell count recovery. METHODS: Rates of CD4 cell increase were determined over 48 weeks among ART-naive individuals (n = 596) commencing ART in a South African community-based ART programme. RESULTS: The CD4 cell count increased from a median of 97 cells/mul at baseline to 261 cells/mul at 48 weeks and the proportion of patients with a CD4 cell count <100 cells/mul decreased from 51% at baseline to just 4% at 48 weeks. A rapid first phase of recovery (0-16 weeks, median rate = 25.5 cells/mul/month) was followed by a slower second phase (16-48 weeks, median rate = 7.7 cells/mul/month). Compared to patients with higher baseline counts, multivariate analysis showed that those with baseline CD4 counts <50 cells/mul had similar rates of phase 1 CD4 cell recovery (P = 0.42), greater rates of phase 2 recovery (P = 0.007) and a lower risk of immunological non-response (P = 0.016). Among those that achieved a CD4 cell count >500 cells/mul at 48 weeks, 19% had baseline CD4 cell counts <50 cells/mul. However, the proportion of these patients that attained a CD4 count 200 cells/mul at 48 weeks was lower than those with higher baseline CD4 cell counts. CONCLUSION: Patients in this cohort with baseline CD4 cell counts <50 cells/mul have equivalent or greater capacity for immunological recovery during 48 weeks of ART compared to those with higher baseline CD4 cell counts. However, their CD4 counts remain <200 cells/mul for a longer period, potentially increasing their risk of morbidity and mortality in the first year of ART.
- ItemOpen AccessThe clinical and economic impact of point-of-care CD4 testing in Mozambique and other resource-limited settings: a cost-effectiveness analysis(Public Library of Science, 2014) Hyle, Emily P; Jani, Ilesh V; Lehe, Jonathan; Su, Amanda E; Wood, Robin; Quevedo, Jorge; Losina, Elena; Bassett, Ingrid V; Pei, Pamela P; Paltiel, A DavidEmily Hyle and colleagues conduct a cost-effectiveness analysis to estimate the clinical and economic impact of point-of-care CD4 testing compared to laboratory-based tests in Mozambique. Please see later in the article for the Editors' Summary
- ItemOpen AccessCombination HIV prevention among MSM in South Africa: results from agent-based modeling(Public Library of Science, 2014) Brookmeyer, Ron; Boren, David; Baral, Stefan D; Bekker, Linda- Gail; Phaswana-Mafuya, Nancy; Beyrer, Chris; Sullivan, Patrick SHIV prevention trials have demonstrated the effectiveness of a number of behavioral and biomedical interventions. HIV prevention packages are combinations of interventions and offer potential to significantly increase the effectiveness of any single intervention. Estimates of the effectiveness of prevention packages are important for guiding the development of prevention strategies and for characterizing effect sizes before embarking on large scale trials. Unfortunately, most research to date has focused on testing single interventions rather than HIV prevention packages. Here we report the results from agent-based modeling of the effectiveness of HIV prevention packages for men who have sex with men (MSM) in South Africa. We consider packages consisting of four components: antiretroviral therapy for HIV infected persons with CD4 count <350; PrEP for high risk uninfected persons; behavioral interventions to reduce rates of unprotected anal intercourse (UAI); and campaigns to increase HIV testing. We considered 163 HIV prevention packages corresponding to different intensity levels of the four components. We performed 2252 simulation runs of our agent-based model to evaluate those packages. We found that a four component package consisting of a 15% reduction in the rate of UAI, 50% PrEP coverage of high risk uninfected persons, 50% reduction in persons who never test for HIV, and 50% ART coverage over and above persons already receiving ART at baseline, could prevent 33.9% of infections over 5 years (95% confidence interval, 31.5, 36.3). The package components with the largest incremental prevention effects were UAI reduction and PrEP coverage. The impact of increased HIV testing was magnified in the presence of PrEP. We find that HIV prevention packages that include both behavioral and biomedical components can in combination prevent significant numbers of infections with levels of coverage, acceptance and adherence that are potentially achievable among MSM in South Africa.
- ItemOpen AccessA community-based mobile clinic model delivering PrEP for HIV prevention to adolescent girls and young women in Cape Town, South Africa(2021-08-28) Rousseau, Elzette; Bekker, Linda-Gail; Julies, Robin F.; Celum, Connie; Morton, Jennifer; Johnson, Rachel; Baeten, Jared M.; O’Malley, GabrielleBackground Daily doses of pre-exposure prophylaxis (PrEP) can reduce the risk of acquiring HIV by more than 95 %. In sub-Saharan Africa, adolescent girls and young women (AGYW) are at disproportionately high risk of acquiring HIV, accounting for 25 % of new infections. There are limited data available on implementation approaches to effectively reach and deliver PrEP to AGYW in high HIV burden communities. Methods We explored the feasibility and acceptability of providing PrEP to AGYW (aged 16–25 years) via a community-based mobile health clinic (CMHC) known as the Tutu Teen Truck (TTT) in Cape Town, South Africa. The TTT integrated PrEP delivery into its provision of comprehensive sexual and reproductive health services (SRHS). We analyzed data from community meetings and in-depth interviews with 30 AGYW PrEP users to understand the benefits and challenges of PrEP delivery in this context. Results A total of 585 young women started PrEP at the TTT between July 2017 – October 2019. During in-depth interviews a subset of 30 AGYW described the CMHC intervention for PrEP delivery as acceptable and accessible. The TTT provided services at times and in neighborhood locations where AGYW organically congregate, thus facilitating service access and generating peer demand for PrEP uptake. The community-based nature of the CMHC, in addition to its adolescent friendly health providers, fostered a trusting provider-community-client relationship and strengthened AGYW HIV prevention self-efficacy. The integration of PrEP and SRHS service delivery was highly valued by AGYW. While the TTT’s integration in the community facilitated acceptability of the PrEP delivery model, challenges faced by the broader community (community riots, violence and severe weather conditions) also at times interrupted PrEP delivery. Conclusions PrEP delivery from a CMHC is feasible and acceptable to young women in South Africa. However, to effectively scale-up PrEP it will be necessary to develop diverse PrEP delivery locations and modalities to meet AGYW HIV prevention needs.
- ItemOpen AccessComparison of six methods to estimate adherence in an ART-naïve cohort in a resource-poor setting: which best predicts virological and resistance outcomes?(BioMed Central, 2017-04-04) Orrell, Catherine; Cohen, Karen; Leisegang, Rory; Bangsberg, David R; Wood, Robin; Maartens, GaryBackground: Incomplete adherence to antiretroviral therapy (ART) results in virologic failure and resistance. It remains unclear which adherence measure best predicts these outcomes. We compared six patient-reported and objective adherence measures in one ART-naïve cohort in South Africa. Methods: We recruited 230 participants from a community ART clinic and prospectively collected demographic data, CD4 count and HIV-RNA at weeks 0, 16 and 48. We quantified adherence using 3-day self-report (SR), clinicbased pill count (CPC), average adherence by pharmacy refill (PR-average), calculation of medication-free days (PR-gaps), efavirenz therapeutic drug monitoring (TDM) and an electronic adherence monitoring device (EAMD). Associations between adherence measures and virologic and genotypic outcomes were modelled using logistic regression, with the area under the curve (AUC) from the receiver operator characteristic (ROC) analyses derived to assess performance of adherence measures in predicting outcomes. Results: At week 48 median (IQR) adherence was: SR 100% (100–100), CPC 100% (95–107), PR-average 103% (95– 105), PR-gaps 100% (95–100) and EAMD 86% (59–94), and efavirenz concentrations were therapeutic (>1 mg/L) in 92%. EAMD, PR-average, PR-gaps and CPC best predicted virological outcome at week 48 with AUC ROC of 0.73 (95% CI 0.61–0.83), 0.73 (95% CI 0.61–0.85), 0.72 (95% CI 0.59–0.84) and 0.64 (95% CI 0.52–0.76) respectively. EAMD, PR-gaps and PR-average were highly predictive of detection of resistance mutations at week 48, with AUC ROC of 0.92 (95% CI 0.87–0.97), 0.86 (0.67–1.0) and 0.83 (95% CI 0.65–1.0) respectively. SR and TDM were poorly predictive of outcomes at week 48. Conclusion: EAMD and both PR measures predicted resistance and virological failure similarly. Pharmacy refill data is a pragmatic adherence measure in resource-limited settings where electronic monitoring is unavailable. Trial registration The trial was retrospectively registered in the Pan African Clinical Trials Registry, number PACTR201311000641402, on the 13 Sep 2013 (www.pactr.org). The first participant was enrolled on the 12th July 2012. The last patient last visit (week 48) was 15 April 2014
- ItemOpen AccessContinued follow-up of Phambili Phase 2b randomized HIV-1 vaccine trial participants supports increased HIV-1 acquisition among vaccinated men(Public Library of Science, 2015) Moodie, Zoe; Metch, Barbara; Bekker, Linda-Gail; Churchyard, Gavin; Nchabeleng, Maphoshane; Mlisana, Koleka; Laher, Fatima; Roux, Surita; Mngadi, Kathryn; Innes, CraigBACKGROUND: The Phase 2b double-blinded, randomized Phambili/HVTN 503 trial evaluated safety and efficacy of the MRK Ad5 gag / pol / nef subtype B HIV-1 preventive vaccine vs placebo in sexually active HIV-1 seronegative participants in South Africa. Enrollment and vaccinations stopped and participants were unblinded but continued follow-up when the Step study evaluating the same vaccine in the Americas, Caribbean, and Australia was unblinded for non-efficacy. Final Phambili analyses found more HIV-1 infections amongst vaccine than placebo recipients, impelling the HVTN 503-S recall study. METHODS: HVTN 503-S sought to enroll all 695 HIV-1 uninfected Phambili participants, provide HIV testing, risk reduction counseling, physical examination, risk behavior assessment and treatment assignment recall. After adding HVTN 503-S data, HIV-1 infection hazard ratios (HR vaccine vs. placebo) were estimated by Cox models. RESULTS: Of the 695 eligible, 465 (67%) enrolled with 230 from the vaccine group and 235 from the placebo group. 38% of the 184 Phambili dropouts were enrolled. Enrollment did not differ by treatment group, gender, or baseline HSV-2. With the additional 1286 person years of 503-S follow-up, the estimated HR over Phambili and HVTN 503-S follow-up was 1.52 (95% CI 1.08-2.15, p = 0.02, 82 vaccine/54 placebo infections). The HR was significant for men (HR = 2.75, 95% CI 1.49, 5.06, p = 0.001) but not for women (HR = 1.12, 95% CI 0.73, 1.72, p = 0.62). CONCLUSION: The additional follow-up from HVTN 503-S supported the Phambili finding of increased HIV-1 acquisition among vaccinated men and strengthened the evidence of lack of vaccine effect among women. Trial Registration clinicaltrials.gov NCT00413725 SA National Health Research Database DOH-27-0207-1539
- ItemOpen AccessCorneal endothelial cells provide evidence of accelerated cellular senescence associated with HIV infection: a case-control study(Public Library of Science, 2013) Pathai, Sophia; Lawn, Stephen D; Shiels, Paul G; Weiss, Helen A; Cook, Colin; Wood, Robin; Gilbert, Clare EBACKGROUND: Cellular senescence may be a key factor in HIV-related premature biological aging. We assessed features of the corneal endothelium that are known to be associated with biological aging, and cellular senescence markers in HIV-infected adults. METHODS: Case-control study of 242 HIV-infected adults and 249 matched controls. Using specular microscopy, the corneal endothelium was assessed for features of aging (low endothelial cell density [ECD], high variation in cell size, and low hexagonality index). Data were analysed by multivariable regression. CDKN2A expression (a cell senescence mediator) was measured in peripheral blood leukocytes and 8-hydroxy-2′-deoxyguanosine (8-OHDG; an oxidative DNA damage marker) levels were measured in plasma. RESULTS: The median age of both groups was 40 years. Among HIV-infected adults, 88% were receiving antiretroviral therapy (ART); their median CD4 count was 468 cells/µL. HIV infection was associated with increased odds of variation in cell size (OR = 1.67; 95% CI: 1.00-2.78, p = 0.04). Among HIV-infected participants, low ECD was independently associated with current CD4 count <200 cells/µL (OR = 2.77; 95%CI: 1.12-6.81, p = 0.03). In participants on ART with undetectable viral load, CDKN2A expression and 8-OHDG levels were higher in those with accelerated aging, as reflected by lower ECD. CONCLUSIONS: The corneal endothelium shows features consistent with HIV-related accelerated senescence, especially among those with poor immune recovery.
- ItemOpen AccessCorrecting mortality for loss to follow-up: a nomogram applied to antiretroviral treatment programmes in sub-Saharan Africa(Public Library of Science, 2011) Egger, Matthias; Spycher, Ben D; Sidle, John; Weigel, Ralf; Geng, Elvin H; Fox, Matthew P; MacPhail, Patrick; van Cutsem, Gilles; Messou, Eugène; Wood, RobinBackground: The World Health Organization estimates that in sub-Saharan Africa about 4 million HIV-infected patients had started antiretroviral therapy (ART) by the end of 2008. Loss of patients to follow-up and care is an important problem for treatment programmes in this region. As mortality is high in these patients compared to patients remaining in care, ART programmes with high rates of loss to follow-up may substantially underestimate mortality of all patients starting ART. Methods and Findings: We developed a nomogram to correct mortality estimates for loss to follow-up, based on the fact that mortality of all patients starting ART in a treatment programme is a weighted average of mortality among patients lost to follow-up and patients remaining in care. The nomogram gives a correction factor based on the percentage of patients lost to follow-up at a given point in time, and the estimated ratio of mortality between patients lost and not lost to follow-up. The mortality observed among patients retained in care is then multiplied by the correction factor to obtain an estimate of programme-level mortality that takes all deaths into account. A web calculator directly calculates the corrected, programme-level mortality with 95% confidence intervals (CIs). We applied the method to 11 ART programmes in sub-Saharan Africa. Patients retained in care had a mortality at 1 year of 1.4% to 12.0%; loss to follow-up ranged from 2.8% to 28.7%; and the correction factor from 1.2 to 8.0. The absolute difference between uncorrected and corrected mortality at 1 year ranged from 1.6% to 9.8%, and was above 5% in four programmes. The largest difference in mortality was in a programme with 28.7% of patients lost to follow-up at 1 year. Conclusions: The amount of bias in mortality estimates can be large in ART programmes with substantial loss to follow-up. Programmes should routinely report mortality among patients retained in care and the proportion of patients lost. A simple nomogram can then be used to estimate mortality among all patients who started ART, for a range of plausible mortality rates among patients lost to follow-up.
- ItemOpen AccessCost effectiveness of cryptococcal antigen screening as a strategy to prevent HIV-associated cryptococcal meningitis in South Africa(Public Library of Science, 2013) Jarvis, Joseph N; Harrison, Thomas S; Lawn, Stephen D; Meintjes, Graeme; Wood, Robin; Cleary, SusanObjectives Cryptococcal meningitis (CM)-related mortality may be prevented by screening patients for sub-clinical cryptococcal antigenaemia (CRAG) at antiretroviral-therapy (ART) initiation and pre-emptively treating those testing positive. Prior to programmatic implementation in South Africa we performed a cost-effectiveness analysis of alternative preventive strategies for CM. Design Cost-effectiveness analysis. METHODS: Using South African data we modelled the cost-effectiveness of four strategies for patients with CD4 cell-counts <100 cells/µl starting ART 1) no screening or prophylaxis (standard of care), 2) universal primary fluconazole prophylaxis, 3) CRAG screening with fluconazole treatment if antigen-positive, 4) CRAG screening with lumbar puncture if antigen-positive and either amphotericin-B for those with CNS disease or fluconazole for those without. Analysis was limited to the first year of ART. RESULTS: The least costly strategy was CRAG screening followed by high-dose fluconazole treatment of all CRAG-positive individuals. This strategy dominated the standard of care at CRAG prevalence ≥0.6%. Although CRAG screening followed by lumbar puncture in all antigen-positive individuals was the most effective strategy clinically, the incremental benefit of LPs and amphotericin therapy for those with CNS disease was small and additional costs were large (US$158 versus US$51per person year; incremental cost effectiveness ratio(ICER) US$889,267 per life year gained). Both CRAG screening strategies are less costly and more clinically effective than current practice. Primary prophylaxis is more effective than current practice, but relatively cost-ineffective (ICER US$20,495). CONCLUSIONS: CRAG screening would be a cost-effective strategy to prevent CM-related mortality among patients initiating ART in South Africa. These findings provide further justification for programmatic implementation of CRAG screening.
- ItemOpen AccessCost-effectiveness of highly active antiretroviral therapy in South Africa(Public Library of Science, 2005) Badri, Motasim; Maartens, Gary; Mandalia, Sundhiya; Bekker, Linda-Gail; Penrod, John R; Platt, Robert W; Wood, Robin; Beck, Eduard JHealthcare costs for HIV-infected South African adults on HAART compared with costs for HIV-infected controls not on HAART. Authors conclude HAART is cost effective.
- ItemOpen AccessCreating an African HIV clinical research and prevention trials network: HIV prevalence, incidence and transmission(Public Library of Science, 2015) Kamali, Anatoli; Price, Matt A; Lakhi, Shabir; Karita, Etienne; Inambao, Mubiana; Sanders, Eduard J; Anzala, Omu; Latka, Mary H; Bekker, Linda-Gail; Kaleebu, PontianoHIV epidemiology informs prevention trial design and program planning. Nine clinical research centers (CRC) in sub-Saharan Africa conducted HIV observational epidemiology studies in populations at risk for HIV infection as part of an HIV prevention and vaccine trial network. Annual HIV incidence ranged from below 2% to above 10% and varied by CRC and risk group, with rates above 5% observed in Zambian men in an HIV-discordant relationship, Ugandan men from Lake Victoria fishing communities, men who have sex with men, and several cohorts of women. HIV incidence tended to fall after the first three months in the study and over calendar time. Among suspected transmission pairs, 28% of HIV infections were not from the reported partner. Volunteers with high incidence were successfully identified and enrolled into large scale cohort studies. Over a quarter of new cases in couples acquired infection from persons other than the suspected transmitting partner.
- ItemOpen AccessDelays in starting antiretroviral therapy in patients with HIV-associated tuberculosis accessing non-integrated clinical services in a South African township(BioMed Central Ltd, 2011) Lawn, Stephen; Campbell, Lucy; Kaplan, Richard; Little, Francesca; Morrow, Carl; Wood, Robin; IeDEA-Southern AfricaBACKGROUND: Delays in the initiation of antiretroviral therapy (ART) in patients with HIV-associated tuberculosis (TB) are associated with increased mortality risk. We examined the timing of ART among patients receiving care provided by non-integrated TB and ART services in Cape Town, South Africa. METHODS: In an observational cohort study, we determined the overall time delay between starting treatment for TB and starting ART in patients treated in Gugulethu township between 2002 and 2008. For patients referred from TB clinics to the separate ART clinic, we quantified and identified risk factors associated with the two component delays between starting TB treatment, enrolment in the ART clinic and subsequent initiation of ART. RESULTS: Among 893 TB patients studied (median CD4 count, 81 cells/muL), the delay between starting TB treatment and starting ART was prolonged (median, 95 days; IQR = 49-155). Delays were shorter in more recent calendar periods and among those with lower CD4 cell counts. However, the median delay was almost three-fold longer for patients referred from separate TB clinics compared to patients whose TB was diagnosed in the ART clinic (116 days versus 41 days, respectively; P < 0.001). In the most recent calendar period, the proportions of patients with CD4 cell counts < 50 cells/muL who started ART within 4 weeks of TB diagnosis were 11.1% for patients referred from TB clinics compared to 54.6% of patients with TB diagnosed in the ART service (P < 0.001). CONCLUSIONS: Delays in starting ART were prolonged, especially for patients referred from separate TB clinics. Non-integration of TB and ART services is likely to be a substantial obstacle to timely initiation of ART.