Henry Sunpath

Prevalence of HIV-1 Drug Resistance after Failure of a First Highly Active Antiretroviral Therapy Regimen in KwaZulu Natal, South Africa

BACKGROUND Emergence of human immunodeficiency virus type 1 (HIV-1) drug resistance may limit the benefits of antiretroviral therapy in resource-limited settings. The prevalence of resistance was assessed among patients from KwaZulu Natal, South Africa, following failure of their first highly active antiretroviral therapy (HAART) regimen. METHODS Genotypic resistance testing was performed on plasma virus samples from patients who experienced virologic failure of their first HAART regimen at 2 clinics in KwaZulu Natal. Clinical and demographic data were obtained from medical records. Regression analysis was performed to determine factors associated with > or =1 significant drug resistance mutation. RESULTS From January 2005 through August 2006, a total of 124 antiretroviral-treated adults who experienced virologic failure were enrolled. The predominant subtype was HIV-1C. Virus samples from 83.5% of participants carried > or =1 significant drug resistance mutation. Dual-class drug-resistant virus was present in 64.3% of participants, and 2.6% had virus with triple-class drug resistance. The most common mutation was M184V/I (64.3% of patients); K103N was present in virus from 51.3%, and V106M was present in virus from 19.1%. Thymidine analog resistance mutations were found in virus from 32.2% of patients, and protease resistance mutations were found in virus from 4.4%. CONCLUSIONS Antiretroviral drug-resistant virus was detected in >80% of South African patients who experienced failure of a first HAART regimen. Patterns of drug resistance reflected drugs used in first-line regimens and viral subtype. Continued surveillance of resistance patterns is warranted to guide selection of second-line regimens.

High rate of K65R for antiretroviral therapy-naive patients with subtype C HIV infection failing a tenofovir-containing first-line regimen.

Objective:We sought to determine the rate of the K65R mutation in patients receiving tenofovir (TDF)-based antiretroviral therapy (ART) with subtype C HIV infection. Design:Retrospective cohort study. Methods:All patients initiated on stavudine (d4T) with lamivudine (3TC) or TDF with 3TC and a nonnucleoside reverse transcriptase inhibitor at McCord Hospital in Durban, South Africa had their charts reviewed. All patients with virologic failure, defined as a viral load more than 1000 copies/ml after 5 months of a first ART regimen, had genotypic resistance testing performed prospectively using a validated in-house assay. Important resistance mutations were selected based upon published mutations in subtype B virus in the Stanford HIV Drug Resistance database. Results:A total of 585 patients were initiated on TDF-containing first-line ART from 3 August 2010 to 17 March 2011. Thirty-five (6.0%) of these patients had virologic failure and 23 of 33 (69.7%) of the virologic failure patients had the K65R mutation. The median (interquartile range) for the baseline CD4 cell count was 105 cells/&mgr;l (49–209) and viral load at virologic failure was 47 571 copies/ml (20 708–202 000). During the same period, 53 patients were initiated on d4T-containing regimens. Two (3.8%) of these patients had virologic failure and one of the virologic failure patients had the K65R mutation. Conclusion:Preliminary data show very high rates (>65%) of K65R for patients failing TDF-based first-line regimens at McCord Hospital with few additional nucleoside reverse transcriptase inhibitor mutations compared with subtype B. These rates may reflect faster in-vivo selection, longer time on a failing regimen or transmitted drug resistance.

Global epidemiology of drug resistance after failure of WHO recommended first-line regimens for adult HIV-1 infection: A multicentre retrospective cohort study

Summary Background Antiretroviral therapy (ART) is crucial for controlling HIV-1 infection through wide-scale treatment as prevention and pre-exposure prophylaxis (PrEP). Potent tenofovir disoproxil fumarate-containing regimens are increasingly used to treat and prevent HIV, although few data exist for frequency and risk factors of acquired drug resistance in regions hardest hit by the HIV pandemic. We aimed to do a global assessment of drug resistance after virological failure with first-line tenofovir-containing ART. Methods The TenoRes collaboration comprises adult HIV treatment cohorts and clinical trials of HIV drug resistance testing in Europe, Latin and North America, sub-Saharan Africa, and Asia. We extracted and harmonised data for patients undergoing genotypic resistance testing after virological failure with a first-line regimen containing tenofovir plus a cytosine analogue (lamivudine or emtricitabine) plus a non-nucleotide reverse-transcriptase inhibitor (NNRTI; efavirenz or nevirapine). We used an individual participant-level meta-analysis and multiple logistic regression to identify covariates associated with drug resistance. Our primary outcome was tenofovir resistance, defined as presence of K65R/N or K70E/G/Q mutations in the reverse transcriptase (RT) gene. Findings We included 1926 patients from 36 countries with treatment failure between 1998 and 2015. Prevalence of tenofovir resistance was highest in sub-Saharan Africa (370/654 [57%]). Pre-ART CD4 cell count was the covariate most strongly associated with the development of tenofovir resistance (odds ratio [OR] 1·50, 95% CI 1·27–1·77 for CD4 cell count <100 cells per μL). Use of lamivudine versus emtricitabine increased the risk of tenofovir resistance across regions (OR 1·48, 95% CI 1·20–1·82). Of 700 individuals with tenofovir resistance, 578 (83%) had cytosine analogue resistance (M184V/I mutation), 543 (78%) had major NNRTI resistance, and 457 (65%) had both. The mean plasma viral load at virological failure was similar in individuals with and without tenofovir resistance (145 700 copies per mL [SE 12 480] versus 133 900 copies per mL [SE 16 650; p=0·626]). Interpretation We recorded drug resistance in a high proportion of patients after virological failure on a tenofovir-containing first-line regimen across low-income and middle-income regions. Effective surveillance for transmission of drug resistance is crucial. Funding The Wellcome Trust.Summary Background Antiretroviral therapy (ART) is crucial for controlling HIV-1 infection through wide-scale treatment as prevention and pre-exposure prophylaxis (PrEP). Potent tenofovir disoproxil fumarate-containing regimens are increasingly used to treat and prevent HIV, although few data exist for frequency and risk factors of acquired drug resistance in regions hardest hit by the HIV pandemic. We aimed to do a global assessment of drug resistance after virological failure with first-line tenofovir-containing ART. Methods The TenoRes collaboration comprises adult HIV treatment cohorts and clinical trials of HIV drug resistance testing in Europe, Latin and North America, sub-Saharan Africa, and Asia. We extracted and harmonised data for patients undergoing genotypic resistance testing after virological failure with a first-line regimen containing tenofovir plus a cytosine analogue (lamivudine or emtricitabine) plus a non-nucleotide reverse-transcriptase inhibitor (NNRTI; efavirenz or nevirapine). We used an individual participant-level meta-analysis and multiple logistic regression to identify covariates associated with drug resistance. Our primary outcome was tenofovir resistance, defined as presence of K65R/N or K70E/G/Q mutations in the reverse transcriptase ( RT ) gene. Findings We included 1926 patients from 36 countries with treatment failure between 1998 and 2015. Prevalence of tenofovir resistance was highest in sub-Saharan Africa (370/654 [57%]). Pre-ART CD4 cell count was the covariate most strongly associated with the development of tenofovir resistance (odds ratio [OR] 1·50, 95% CI 1·27–1·77 for CD4 cell count Interpretation We recorded drug resistance in a high proportion of patients after virological failure on a tenofovir-containing first-line regimen across low-income and middle-income regions. Effective surveillance for transmission of drug resistance is crucial. Funding The Wellcome Trust.

A high incidence of nucleoside reverse transcriptase inhibitor (NRTI)-induced lactic acidosis in HIV-infected patients in a South African context

OBJECTIVE To determine the incidence of and predisposing risk factors for lactic acidosis in HIV-infected patients on antiretroviral drugs in South Africa. DESIGN Observational case series. SETTING Sinikithemba HIV Clinic, McCord Hospital, Durban. SUBJECTS Eight hundred and ninety-one HIV-positive patients on highly active antiretroviral therapy (HAART) during an 18-month period commencing in January 2004. MEASUREMENTS AND RESULTS Fourteen cases of lactic acidosis (incidence rate of 19 (95% confidence interval (CI): 9-29) cases per 1,000 person-years of treatment) were reported. All cases were female, with a median age of 36 years and a median weight of 81 kg. The median time on HAART before developing lactic acidosis was 7.5 months and the median peak lactate level was 9.3 mmol/l. All cases were on stavudine (d4T), lamivudine (3TC) and 1 non-NRTI. The case mortality rate was 29% (4 patients). CONCLUSIONS The incidence rate is higher than reported in studies in developed countries. This may be due to d4T, which is recommended as a first-line antiretroviral drug in South Africa. This implication raises the question whether it is an appropriate drug in first-line treatment of patients with predisposing risk factors such as female gender and being overweight.

Antiretroviral Therapy—Associated Toxicities in the Resource-Poor World: The Challenge of a Limited Formulary

Toxicities related to antiretroviral therapy make long-term adherence to therapy difficult for patients and present challenges to providers, especially those in the resource-poor world who work with a limited formulary. In resource-poor settings, where limited drug options are the rule, when and how to change therapy are especially difficult problems. Drugs such as stavudine and didanosine are associated with serious metabolic complications, such as lactic acidosis, pancreatitis, and peripheral neuropathy. Antiretroviral agents associated with fewer metabolic effects, such as tenofovir and abacavir, remain widely unavailable. Because the current formulary restrictions appear to be unlikely to change quickly, providers in resource-poor countries must be familiar with the common adverse events-including metabolic complications, hypersensitivity reactions, anemia, and liver enzyme abnormalities-and must understand how to manage them with what is locally available. Most importantly, to avoid drug toxicities, a larger formulary is needed in resource-poor settings, and this must be a high priority for policy makers and health care professionals involved in treating human immunodeficiency virus infection globally.

Outcomes after virologic failure of first-line ART in South Africa.

Objective:To determine initial 24-week outcomes among prospectively enrolled patients with failure of initial antiretroviral therapy (ART). Methods:Baseline virologic failure was defined as HIV-1 viral load greater than 1000 copies/ml. Second-line ART was informed by results of genotype testing and selected from agents in the South-African public sector. Twenty-four week endpoints included virologic suppression and mortality. Results:The cohort consisted of 141 patients (median CD4 cell count and viral load at failure of 173 cells/μl and 17 500 copies/ml). The median prior duration of initial ART was 12.0 months. At least one major resistance mutation was found in 87% of patients.After 24 weeks of follow-up, intent-to-treat virologic suppression (<50 copies/ml) was 65%, as-treated virologic suppression was 78%, the median CD4 cell count improvement was 88 cells/μl and the mortality was 6%. The median CD4 cell count at initial virologic failure among those who died was 70 cells/μl, compared to 182 cells/μl among patients who survived (P = 0.01). Patients with wild-type virus at initial failure (N = 19) had inferior outcomes after switch. The presence of nucleoside analogue resistance mutations at failure did not affect early efficacy of boosted-protease inhibitor regimens. Conclusions:Virologic monitoring linked to resistance testing helped demonstrate the efficacy of lopinavir/ritonavir-containing second-line regimens in South Africa. A switch to second-line regimens in patients with virologic failure and drug resistance has substantial and rapid immunological and clinical benefits. Resistance testing identified a high-risk group without resistance who might benefit from increased medication access and/or adherence support.

Second-line antiretroviral therapy: Long-term outcomes in South Africa

Background:Currently, boosted protease inhibitor–containing regimens are the only option after first-line regimen failure available for patients in most resource-limited settings, yet little is known about long-term adherence and outcomes. Methods:We enrolled patients with virologic failure (VF) who initiated lopinavir/ritonavir–containing second-line antiretroviral therapy (ART). Medication possession ratios were calculated using pharmacy refill dates. Factors associated with 12-month second-line virologic suppression [viral load (VL) <50 copies/mL] and adherence were determined. Results:One hundred six patients (median CD4 count and VL at failure: 153 cells/mm3 and 28,548 copies/mL, respectively) were enrolled. Adherence improved after second-line ART switch (median adherence 6 months prior, 67%; median adherence during initial 6 months of second-line ART, 100%; P = 0.001). Higher levels of adherence during second-line ART was associated with virologic suppression at month 12 of ART (odds ratio 2.5 per 10% adherence increase, 95% CI 1.3 to 4.8, P = 0.01). Time to virologic suppression was most rapid among patients with 91%–100% adherence compared with patients with 80%–90% and <80% adherence (log rank test, P = 0.01). VF during 24 months of second-line ART was moderate (month 12: 25%, n = 32/126; month 18: 21%, n = 23/112; and month 24: 25%, n = 25/99). Conclusions:The switch to second-line ART in South Africa was associated with an improvement in adherence, however, a moderate ongoing rate of VF—among approximately 25% of patients receiving second-line ART patients at each follow-up interval—was a cause for concern. Adherence level was associated with second-line ART virologic outcome, helping explain why some patients achieved virologic suppression after switch and others did not.

Use of a WHO-recommended algorithm to reduce mortality in seriously ill patients with HIV infection and smear-negative pulmonary tuberculosis in South Africa: an observational cohort study

BACKGROUND In 2007, WHO released revised recommendations and an algorithm for the diagnosis and treatment of smear-negative pulmonary tuberculosis in seriously ill people living with HIV/AIDS. We aimed to assess the effect of the recommendations on clinical outcome in patients in South Africa. METHODS We enrolled seriously ill patients (aged ≥15 years) with HIV infection and suspected smear-negative pulmonary tuberculosis from three hospitals in KwaZulu-Natal, South Africa. Patients were consecutively enrolled into two cohorts: the first cohort was managed according to standard practice, and the second according to the WHO-recommended algorithm. The primary endpoints were rates of continued stay in hospital at 7 days after admission and survival at 8 weeks after admission. FINDINGS 338 patients were enrolled in the standard practice cohort between August, 2008, and February, 2009, and 187 were enrolled in the algorithm cohort between March, 2009, and December, 2009. 7 days after hospital admission, 27% (n=50) of patients in the algorithm cohort were still in hospital, compared with 38% (n=130) in the standard practice cohort (rate ratio 0·70, 95% CI 0·53-0·91; p=0·009). 8 weeks after admission, 83% (n=156) of patients in the algorithm cohort were alive, compared with 68% (n=230) in the standard practice cohort (1·23, 1·11-1·35; p=0·0001), with effect modified by hospital location. INTERPRETATION In seriously ill patients with HIV infection and suspected smear-negative pulmonary tuberculosis, early antituberculosis treatment according to the WHO algorithm could significantly reduce mortality in South Africa. FUNDING US Presidents Emergency Plan for AIDS Relief.

HIV Online Provider Education (HOPE): The Internet as a Tool for Training in HIV Medicine

Human immunodeficiency virus (HIV) treatment programs in resource-limited areas are expanding rapidly. Providing training and education to health care providers in these programs is a major challenge. We have employed Internet-based conferencing technology to conduct interactive case-based training conferences with health care professionals in Africa, Asia, and the Caribbean. This online program may be a model for other efforts to provide education to health care providers treating HIV-infected patients in the developing world.

Procollagen III N-terminal Propeptide and Desmosine are Released by Matrix Destruction in Pulmonary Tuberculosis

BACKGROUND Tuberculosis is transmitted by patients with pulmonary disease. Matrix metalloproteinases (MMPs) drive lung destruction in tuberculosis but the resulting matrix degradation products (MDPs) have not been studied. We investigate the hypothesis that MMP activity generates matrix turnover products as correlates of lung pathology. METHODS Induced sputum and plasma were collected prospectively from human immunodeficiency virus (HIV) positive and negative patients with pulmonary tuberculosis and controls. Concentrations of MDPs and MMPs were analyzed by ELISA and Luminex array in 2 patient cohorts. RESULTS Procollagen III N-terminal propeptide (PIIINP) was 3.8-fold higher in induced sputum of HIV-uninfected tuberculosis patients compared to controls and desmosine, released during elastin degradation, was 2.4-fold higher. PIIINP was elevated in plasma of tuberculosis patients. Plasma PIIINP correlated with induced sputum MMP-1 concentrations and radiological scores, demonstrating that circulating MDPs reflect lung destruction. In a second patient cohort of mixed HIV seroprevalence, plasma PIIINP concentration was increased 3.0-fold above controls (P < .001). Plasma matrix metalloproteinase-8 concentrations were also higher in tuberculosis patients (P = .001). Receiver operating characteristic analysis utilizing these 2 variables demonstrated an area under the curve of 0.832 (P < .001). CONCLUSIONS In pulmonary tuberculosis, MMP-driven immunopathology generates matrix degradation products.