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Dive into the research topics where James H. McMahon is active.

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Featured researches published by James H. McMahon.


PLOS Pathogens | 2014

Activation of HIV Transcription with Short-Course Vorinostat in HIV-Infected Patients on Suppressive Antiretroviral Therapy

Julian Elliott; Fiona Wightman; Ajantha Solomon; Khader Ghneim; Jeffrey D. Ahlers; Mark J. Cameron; Miranda Z. Smith; Tim Spelman; James H. McMahon; Pushparaj Velayudham; Gregor J. Brown; Janine Roney; Jo Watson; Miles Prince; Jennifer Hoy; Nicolas Chomont; Rémi Fromentin; Francesco A. Procopio; Joumana Zeidan; Sarah Palmer; Lina Odevall; Ricky W. Johnstone; Ben P. Martin; Elizabeth Sinclair; Steven G. Deeks; Daria J. Hazuda; Paul U. Cameron; Rafick-Pierre Sekaly; Sharon R. Lewin

Human immunodeficiency virus (HIV) persistence in latently infected resting memory CD4+ T-cells is the major barrier to HIV cure. Cellular histone deacetylases (HDACs) are important in maintaining HIV latency and histone deacetylase inhibitors (HDACi) may reverse latency by activating HIV transcription from latently infected CD4+ T-cells. We performed a single arm, open label, proof-of-concept study in which vorinostat, a pan-HDACi, was administered 400 mg orally once daily for 14 days to 20 HIV-infected individuals on suppressive antiretroviral therapy (ART). The primary endpoint was change in cell associated unspliced (CA-US) HIV RNA in total CD4+ T-cells from blood at day 14. The study is registered at ClinicalTrials.gov (NCT01365065). Vorinostat was safe and well tolerated and there were no dose modifications or study drug discontinuations. CA-US HIV RNA in blood increased significantly in 18/20 patients (90%) with a median fold change from baseline to peak value of 7.4 (IQR 3.4, 9.1). CA-US RNA was significantly elevated 8 hours post drug and remained elevated 70 days after last dose. Significant early changes in expression of genes associated with chromatin remodeling and activation of HIV transcription correlated with the magnitude of increased CA-US HIV RNA. There were no statistically significant changes in plasma HIV RNA, concentration of HIV DNA, integrated DNA, inducible virus in CD4+ T-cells or markers of T-cell activation. Vorinostat induced a significant and sustained increase in HIV transcription from latency in the majority of HIV-infected patients. However, additional interventions will be needed to efficiently induce virus production and ultimately eliminate latently infected cells. Trial Registration ClinicalTrials.gov NCT01365065


Clinical Infectious Diseases | 2011

Pharmacy Adherence Measures to Assess Adherence to Antiretroviral Therapy: Review of the Literature and Implications for Treatment Monitoring

James H. McMahon; Michael R. Jordan; Karen Kelley; Silvia Bertagnolio; Steven Y. Hong; Christine Wanke; Sharon R. Lewin; Julian Elliott

Prescription or pill-based methods for estimating adherence to antiretroviral therapy (ART), pharmacy adherence measures (PAMs), are objective estimates calculated from routinely collected pharmacy data. We conducted a literature review to evaluate PAMs, including their association with virological and other clinical outcomes, their efficacy compared with other adherence measures, and factors to consider when selecting a PAM to monitor adherence. PAMs were classified into 3 categories: medication possession ratio (MPR), pill count (PC), and pill pick-up (PPU). Data exist to recommend PAMs over self-reported adherence. PAMs consistently predicted patient outcomes, but additional studies are needed to determine the most predictive PAM parameters. Current evidence suggests that shorter duration of adherence assessment (≤ 6 months) and use of PAMs to predict future outcomes may be less accurate. PAMs which incorporate the number of days for which ART was prescribed without the counting of remnant pills, are reasonable minimum-resource methods to assess adherence to ART.


The Lancet HIV | 2015

Short-term administration of disulfiram for reversal of latent HIV infection: a phase 2 dose-escalation study

Julian Elliott; James H. McMahon; Christina C. Chang; Sulggi A. Lee; Wendy Hartogensis; Namandjé N. Bumpus; Rada Savic; Janine Roney; Ajantha Solomon; Michael Piatak; Robert J. Gorelick; Jeff Lifson; Peter Bacchetti; Steven G. Deeks; Sharon R. Lewin

BACKGROUND In vitro, disulfiram activated HIV transcription in a primary T-cell model of HIV latency and in a pilot clinical study increased plasma HIV RNA in individuals with adequate drug exposure. We assessed the effect of disulfiram on HIV transcription in a dose-escalation study. METHODS In this prospective dose-escalation study, to optimise disulfiram exposure we included adults with HIV on suppressive antiretroviral therapy, with plasma HIV RNA of less than 50 copies per mL and a CD4 cell count greater than 350 cells per μL. Participants were allocated sequentially to one of three dosing groups (500 mg, 1000 mg, and 2000 mg) and received disulfiram daily for 3 days. Only the staff who did laboratory assays were masked to group assignment. The primary endpoint was change in cell-associated unspliced HIV RNA in CD4 cells. The primary analysis method was a negative binomial regression, with the number of copies as the outcome variable and the input total RNA or plasma volume as an exposure variable, which is equivalent to modelling copies or input. We used these models to estimate changes from before disulfiram to timepoints during and after disulfiram administration. This study is registered with ClinicalTrials.gov, number NCT01944371. FINDINGS Of 34 participants screened for eligibility at The Alfred Hospital (Melbourne, VIC, Australia), and San Francisco General Hospital (San Francisco, CA, USA), 30 people were enrolled between Sept 24, 2013, and March 31, 2014. The estimated fold increases in cell-associated unspliced HIV RNA from baseline were 1·7 (95% CI 1·3-2·2; p<0·0001) to the timepoint during disulfiram treatment and 2·1 (1·5-2·9; p<0·0001) to the timepoint after disulfiram in the 500 mg group; 1·9 (1·6-2·4; p<0·0001) and 2·5 (1·9-3·3; p<0·0001) in the 1000 mg group; and 1·6 (1·2-2·1; p=0·0026) and 2·1 (1·5-3·1; p=0·0001) in the 2000 mg group. No deaths occurred, and no serious adverse events were noted. Disulfiram was well tolerated at all doses. INTERPRETATION Short-term administration of disulfiram resulted in increases in cell-associated unspliced HIV RNA at all doses, consistent with activating HIV latency. Disulfiram may be suited for future studies of combination and prolonged therapy to activate latent HIV. FUNDING The Foundation for AIDS Research (amfAR); National Institute of Allergy and Infectious Diseases, National Institutes of Health; Australian National Health and Medical Research Council.


Bulletin of The World Health Organization | 2013

Viral suppression after 12 months of antiretroviral therapy in low- and middle-income countries: a systematic review

James H. McMahon; Julian Elliott; Silvia Bertagnolio; Rachel Kubiak; Michael R. Jordan

OBJECTIVE To establish estimates of viral suppression in low- and middle-income countries (LMICs) in patients who received antiretroviral therapy (ART) for human immunodeficiency virus (HIV) infection. METHODS Data on viral suppression after 12 months of ART in LMICs were collected from articles published in 2003 to 2011 and from abstracts of conferences held between 2009 and 2011. Pooled proportions for on-treatment and intention-to-treat populations were used as summary estimates. Random-effects models were used for heterogeneous groups of studies (I (2) > 75%). FINDINGS Overall, 49 studies covering 48 cohorts and 30 016 individuals met the inclusion criteria. With thresholds for suppression between 300 and 500 copies of viral ribonucleic acid (RNA) per ml of plasma, 84.3% (95% confidence interval, CI: 80.4-87.9) of the pooled on-treatment population and 70.5% (95% CI: 65.2-75.6) of the intention-to-treat population showed suppression. Use of different viral RNA thresholds changed the proportions showing suppression: to 84% and 76% of the on-treatment population with thresholds set above 300 and at or below 200 RNA copies per ml, respectively, and to 78%, 71% and 63% of the intention-to-treat population at thresholds set at 1000, 300 to 500, and 200 or fewer copies per ml, respectively. CONCLUSION The pooled estimates of viral suppression recorded after 12 months of ART in LMICs provide benchmarks that other ART programmes can use to set realistic goals and perform predictive modelling. Evidence from this review suggests that the current international target - i.e. viral suppression in > 70% of the intention-to-treat population, with a threshold of 1000 copies per ml - should be revised upwards.


Clinical Infectious Diseases | 2015

Long-term Virological Outcomes of First-Line Antiretroviral Therapy for HIV-1 in Low- and Middle-Income Countries: A Systematic Review and Meta-analysis

T. Sonia Boender; Kim C. E. Sigaloff; James H. McMahon; Sasisopin Kiertiburanakul; Michael R. Jordan; Jhoney Barcarolo; Nathan Ford; Tobias F. Rinke de Wit; Silvia Bertagnolio

BACKGROUND More than 11.7 million people are currently receiving antiretroviral therapy (ART) in low- and middle-income countries (LMICs), and focused efforts are needed to ensure high levels of adherence and to minimize treatment failure. Recently, international targets have emphasized the importance of long-term virological suppression as a key measure of program performance. METHODS We systematically reviewed publications and conference abstracts published between January 2006 and May 2013 that reported virological outcomes among human immunodeficiency virus type 1 (HIV-1)-infected adults receiving first-line ART for up to 5 years in LMICs. Summary estimates of virological suppression after 6, 12, 24, 36, 48, and 60 months of ART were analyzed using random-effects meta-analysis. Intention-to-treat (ITT) analysis assumed all participants who were lost to follow-up, died, or stopped ART as having virological failure. RESULTS Summary estimates of virological suppression remained >80% for up to 60 months of ART for all 184 included cohorts. ITT analysis yielded 74.7% (95% confidence interval [CI], 72.2-77.2) suppression after 6 months and 61.8% (95% CI, 44.0-79.7) suppression after 48 months on ART. Switches to second-line ART were reported scarcely. CONCLUSIONS Among individuals retained on ART, virological suppression rates during the first 5 years of ART were high (>80%) and stable. Suppression rates in ITT analysis declined during 4 years.


Clinical Infectious Diseases | 2012

Update on World Health Organization HIV drug resistance prevention and assessment strategy: 2004-2011

Michael R. Jordan; Diane Bennett; Mark A. Wainberg; Diane V. Havlir; S Hammer; Chunfu Yang; Lynn Morris; Martine Peeters; A.M.J. Wensing; Neil T. Parkin; Jean B. Nachega; Andrew N. Phillips; A. De Luca; Elvin Geng; Alexandra Calmy; Elliot Raizes; Paul Sandstrom; C P Archibald; Joseph H. Perriëns; C Mcclure; Steven Y. Hong; James H. McMahon; N Dedes; D. Sutherland; Silvia Bertagnolio

The HIV drug resistance (HIVDR) prevention and assessment strategy, developed by the World Health Organization (WHO) in partnership with HIVResNet, includes monitoring of HIVDR early warning indicators, surveys to assess acquired and transmitted HIVDR, and development of an accredited HIVDR genotyping laboratory network to support survey implementation in resource-limited settings. As of June 2011, 52 countries had implemented at least 1 element of the strategy, and 27 laboratories had been accredited. As access to antiretrovirals expands under the WHO/Joint United Nations Programme on HIV/AIDS Treatment 2.0 initiative, it is essential to strengthen HIVDR surveillance efforts in the face of increasing concern about HIVDR emergence and transmission.


Clinical Infectious Diseases | 2012

HIV Drug Resistance Early Warning Indicators in Cohorts of Individuals Starting Antiretroviral Therapy Between 2004 and 2009: World Health Organization Global Report From 50 Countries

Diane Bennett; Michael R. Jordan; Silvia Bertagnolio; Steven Y. Hong; Giovanni Ravasi; James H. McMahon; Ahmed Saadani; Karen Kelley

The World Health Organization developed a set of human immunodeficiency virus drug resistance (HIVDR) early warning indicators (EWIs) to assess antiretroviral therapy clinic and program factors associated with HIVDR. EWIs are monitored by abstracting data routinely recorded in clinical records, and the results enable clinics and program managers to identify problems that should be addressed to minimize preventable emergence of HIVDR in clinic populations. As of June 2011, 50 countries monitored EWIs, covering 131 686 patients initiating antiretroviral treatment between 2004 and 2009 at 2107 clinics. HIVDR prevention is associated with patient care (appropriate prescribing and patient monitoring), patient behavior (adherence), and clinic/program management efforts to reduce treatment interruptions (follow up, retention on first-line ART, procurement and supply management of antiretroviral drugs). EWIs measure these factors and the results have been used to optimize patient and population treatment outcomes.


Aids and Behavior | 2011

Poverty, Hunger, Education, and Residential Status Impact Survival in HIV

James H. McMahon; Christine Wanke; Norma Terrin; Sally Skinner; Tamsin A. Knox

Despite combination antiretroviral therapy (ART), HIV infected people have higher mortality than non-infected. Lower socioeconomic status (SES) predicts higher mortality in many chronic illnesses but data in people with HIV is limited. We evaluated 878 HIV infected individuals followed from 1995 to 2005. Cox proportional hazards for all-cause mortality were estimated for SES measures and other factors. Mixed effects analyses examined how SES impacts factors predicting death. The 200 who died were older, had lower CD4 counts, and higher viral loads (VL). Age, transmission category, education, albumin, CD4 counts, VL, hunger, and poverty predicted death in univariate analyses; age, CD4 counts, albumin, VL, and poverty in the multivariable model. Mixed models showed associations between (1) CD4 counts with education and hunger; (2) albumin with education, homelessness, and poverty; and (3) VL with education and hunger. SES contributes to mortality in HIV infected persons directly and indirectly, and should be a target of health policy in this population.


Journal of the International AIDS Society | 2015

The HIV care cascade: a systematic review of data sources, methodology and comparability

Nicholas A. Medland; James H. McMahon; Eric P. F. Chow; Julian Elliott; Jennifer Hoy; Christopher K. Fairley

The cascade of HIV diagnosis, care and treatment (HIV care cascade) is increasingly used to direct and evaluate interventions to increase population antiretroviral therapy (ART) coverage, a key component of treatment as prevention. The ability to compare cascades over time, sub‐population, jurisdiction or country is important. However, differences in data sources and methodology used to construct the HIV care cascade might limit its comparability and ultimately its utility. Our aim was to review systematically the different methods used to estimate and report the HIV care cascade and their comparability.


Journal of Acquired Immune Deficiency Syndromes | 2011

Repeated assessments of food security predict CD4 change in the setting of antiretroviral therapy

James H. McMahon; Christine Wanke; Julian Elliott; Sally Skinner; Alice M. Tang

Food insecurity is highly prevalent in HIV-infected populations, and analyses utilizing multiple assessments of food security to predict CD4 change are lacking. Five hundred Ninety-two patients with ≥ 4 food security assessments were followed prospectively. In the final model, for patients using antiretroviral therapy, increases in CD4 counts were on average 99.5 cells less for individuals with at least 1 episode of food insecurity compared with those consistently food secure (P < 0.001). Other sociodemographic factors were not predictive. Repeated assessments of food security are potent predictors of treatment response notwithstanding antiretroviral therapy use. Potential mechanisms for this association are proposed.

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Tim Spelman

Royal Melbourne Hospital

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