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Moore CL, Stöhr W, Crook AM, Richert L, Leliévre JD, Pantaleo G, García F, Vella S, Lévy Y, Thiébaut R, McCormack S. Multi-arm, multi-stage randomised controlled trials for evaluating therapeutic HIV cure interventions. Lancet HIV 2020; 6:e334-e340. [PMID: 31047670 DOI: 10.1016/s2352-3018(19)30082-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 03/12/2019] [Accepted: 03/15/2019] [Indexed: 12/22/2022]
Abstract
The evaluation of immune-based approaches to achieve an antiretroviral therapy free remission of HIV infection requires proven efficacy through antiretroviral therapy interruption placebo-controlled trials. This approach is not without risk to participants and innovative trial designs need to be developed that minimise the number of participants treated with placebo and ineffective candidates. Multi-arm, multi-stage (MAMS) trial designs can be used in this context to accelerate the development of an immune-based therapeutic agent for HIV cure. Issues related to implementing a MAMS design within the planned EHVA T01 trial are considered here. EHVA T01 is a multicentre, MAMS, double-blind, phase 1 and 2 trial that aims to evaluate the effect of immune interventions on viral control in HIV-1 infected participants following analytic treatment interruption. The application of a MAMS design increases the likelihood that the EHVA T01 trial will identify a successful treatment and minimises the number of participants undergoing analytical treatment interruptions who have been treated with futile agents. The use of a MAMS design is a promising strategy to evaluate complex immune-based approaches aimed at curing HIV-infection, particularly relevant to the pipeline with multiple agents requiring examination.
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Affiliation(s)
- Cecilia L Moore
- Medical Research Council Clinical Trials Unit, Institute of Clinical Trials and Methodology, University College London, London, UK.
| | - Wolfgang Stöhr
- Medical Research Council Clinical Trials Unit, Institute of Clinical Trials and Methodology, University College London, London, UK
| | - Angela M Crook
- Medical Research Council Clinical Trials Unit, Institute of Clinical Trials and Methodology, University College London, London, UK
| | - Laura Richert
- Vaccine Research Institute, Créteil, France; University of Bordeaux, Inserm, Bordeaux Population Health Research Center, Team SISTM, UMR 1219, and Inria, Bordeaux, France; European Clinical Trials Platform and Development, and French Clinical Research Infrastructure Network, CIC 1401, University of Bordeaux, Inserm, CHU Bordeaux, Bordeaux, France
| | - Jean-Daniel Leliévre
- Vaccine Research Institute, Créteil, France; INSERM U955, Paris Est Créteil University, Créteil, France
| | - Giuseppe Pantaleo
- Service of Immunology and Allergy, and Swiss Vaccine Research Institute, Lausanne University Hospital, University of Lausanne, Lausanne, Switzerland
| | - Felipe García
- Infectious Diseases Department, Hospital Clinic of Barcelona-HIVACAT, University of Barcelona, Barcelona, Spain; Retrovirology and Viral Immunopathology Laboratory, AIDS Research Group, August Pi i Sunyer Biomedical Research Institute (IDIBAPS)-HIVACAT, Barcelona, Spain
| | - Stefano Vella
- Center for Global Health, Istituto Superiore di Sanità, Rome, Italy
| | - Yves Lévy
- Vaccine Research Institute, Créteil, France; INSERM U955, Paris Est Créteil University, Créteil, France; AP-HP, Hôpital Henri-Mondor Albert-Chenevier, Service d'Immunologie Clinique et Maladies Infectieuses, Créteil, France
| | - Rodolphe Thiébaut
- Vaccine Research Institute, Créteil, France; University of Bordeaux, Inserm, Bordeaux Population Health Research Center, Team SISTM, UMR 1219, and Inria, Bordeaux, France; European Clinical Trials Platform and Development, and French Clinical Research Infrastructure Network, CIC 1401, University of Bordeaux, Inserm, CHU Bordeaux, Bordeaux, France
| | - Sheena McCormack
- Medical Research Council Clinical Trials Unit, Institute of Clinical Trials and Methodology, University College London, London, UK
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Graziani GM, Angel JB. Evaluating the efficacy of therapeutic HIV vaccines through analytical treatment interruptions. J Int AIDS Soc 2015; 18:20497. [PMID: 26561337 PMCID: PMC4641978 DOI: 10.7448/ias.18.1.20497] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Revised: 09/16/2015] [Accepted: 10/08/2015] [Indexed: 02/08/2023] Open
Abstract
INTRODUCTION The development of an effective therapeutic HIV vaccine that induces immunologic control of viral replication, thereby eliminating or reducing the need for antiretroviral therapy (ART), would be of great value. Besides the obvious challenges of developing a therapeutic vaccine that would generate effective, sustained anti-HIV immunity in infected individuals is the issue of how to best assess the efficacy of vaccine candidates. DISCUSSION This review discusses the various outcome measures assessed in therapeutic HIV vaccine clinical trials involving individuals receiving suppressive ART, with a particular focus on the role of analytical treatment interruption (ATI) as a way to assess the virologic control induced by an immunotherapy. This strategy is critical given that there are otherwise no readily available measures to determine the ability of a vaccine-induced immune response to effectively control HIV replication. The various outcome measures that have been used to assess vaccine efficacy in published therapeutic HIV vaccine clinical trials will also be discussed. Outcome measures have included the kinetics of viral rebound, the new viral set point and changes in the size of the viral reservoir. Clinically relevant outcomes such as the CD4 decline, the time to resume therapy or the time to meet the criterion to resume therapy, the proportion of participants who resume therapy and/or the development of clinical symptoms such as acute retroviral syndrome are also measures of vaccine efficacy. CONCLUSIONS Given the lack of consistency between therapeutic HIV vaccine trials in how efficacy is assessed, comparing vaccines has been difficult. It would, therefore, be beneficial to determine the most clinically relevant measure for use in future studies. Other recommendations for future clinical trials also include studying compartments in addition to blood and replacing ATIs with single-copy assays in situations in which the use of an ATI is not ideal.
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Affiliation(s)
| | - Jonathan B Angel
- Ottawa Hospital Research Institute, Ottawa, ON, Canada
- Division of Infectious Disease, The Ottawa Hospital, Ottawa, ON, Canada;
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Li JZ, Brumme CJ, Lederman MM, Brumme ZL, Wang H, Spritzler J, Carrington M, Medvik K, Walker BD, Schooley RT, Kuritzkes DR. Characteristics and outcomes of initial virologic suppressors during analytic treatment interruption in a therapeutic HIV-1 gag vaccine trial. PLoS One 2012; 7:e34134. [PMID: 22479542 PMCID: PMC3316607 DOI: 10.1371/journal.pone.0034134] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2011] [Accepted: 02/22/2012] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND In the placebo-controlled trial ACTG A5197, a trend favoring viral suppression was seen in the HIV-1-infected subjects who received a recombinant Ad5 HIV-1 gag vaccine. OBJECTIVE To identify individuals with initial viral suppression (plasma HIV-1 RNA set point <3.0 log(10) copies/ml) during the analytic treatment interruption (ATI) and evaluate the durability and correlates of virologic control and characteristics of HIV sequence evolution. METHODS HIV-1 gag and pol RNA were amplified and sequenced from plasma obtained during the ATI. Immune responses were measured by flow cytometric analysis and intracellular cytokine expression assays. Characteristics of those with and without initial viral suppression were compared using the Wilcoxon rank sum and Fisher's exact tests. RESULTS Eleven out of 104 participants (10.6%) were classified as initial virologic suppressors, nine of whom had received the vaccine. Initial virologic suppressors had significantly less CD4+ cell decline by ATI week 16 as compared to non-suppressors (median 7 CD4+ cell gain vs. 247 CD4+ cell loss, P = 0.04). However, of the ten initial virologic suppressors with a pVL at ATI week 49, only three maintained pVL <3.0 log(10) copies/ml. HIV-1 Gag-specific CD4+ interferon-γ responses were not associated with initial virologic suppression and no evidence of vaccine-driven HIV sequence evolution was detected. Participants with initial virologic suppression were found to have a lower percentage of CD4+ CTLA-4+ cells prior to treatment interruption, but a greater proportion of HIV-1 Gag-reactive CD4+ TNF-α+ cells expressing either CTLA-4 or PD-1. CONCLUSIONS Among individuals participating in a rAd5 therapeutic HIV-1 gag vaccine trial, initial viral suppression was found in a subset of patients, but this response was not sustained. The association between CTLA-4 and PD-1 expression on CD4+ T cells and virologic outcome warrants further study in trials of other therapeutic vaccines in development. TRIAL REGISTRATION ClinicalTrials.gov NCT00080106.
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Affiliation(s)
- Jonathan Z Li
- Division of Infectious Diseases, Brigham and Women's Hospital, Boston, Massachusetts, United States of America.
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Willberg CB, McConnell JJ, Eriksson EM, Bragg LA, York VA, Liegler TJ, Hecht FM, Grant RM, Nixon DF. Immunity to HIV-1 is influenced by continued natural exposure to exogenous virus. PLoS Pathog 2008; 4:e1000185. [PMID: 18949024 PMCID: PMC2562513 DOI: 10.1371/journal.ppat.1000185] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2008] [Accepted: 09/23/2008] [Indexed: 11/18/2022] Open
Abstract
Unprotected sexual intercourse between individuals who are both infected with HIV-1 can lead to exposure to their partner's virus, and potentially to super-infection. However, the immunological consequences of continued exposure to HIV-1 by individuals already infected, has to our knowledge never been reported. We measured T cell responses in 49 HIV-1 infected individuals who were on antiretroviral therapy with suppressed viral loads. All the individuals were in a long-term sexual partnership with another HIV-1 infected individual, who was either also on HAART and suppressing their viral loads, or viremic (>9000 copies/ml). T cell responses to HIV-1 epitopes were measured directly ex-vivo by the IFN-γ enzyme linked immuno-spot assay and by cytokine flow cytometry. Sexual exposure data was generated from questionnaires given to both individuals within each partnership. Individuals who continued to have regular sexual contact with a HIV-1 infected viremic partner had significantly higher frequencies of HIV-1-specific T cell responses, compared to individuals with aviremic partners. Strikingly, the magnitude of the HIV-1-specific T cell response correlated strongly with the level and route of exposure. Responses consisted of both CD4+ and CD8+ T cell subsets. Longitudinally, decreases in exposure were mirrored by a lower T cell response. However, no evidence for systemic super-infection was found in any of the individuals. Continued sexual exposure to exogenous HIV-1 was associated with increased HIV-1-specific T cell responses, in the absence of systemic super-infection, and correlated with the level and type of exposure. Serosorting, the practice of seeking to engage in unprotected sexual activities only with partners who are of the same HIV-1 status, is a growing trend. Unprotected sexual intercourse between two HIV-1 infected individuals can lead to consequences such as HIV-1 super-infection. However, continued exposure to HIV-1 may also have an important influence on the immune response. Here, we explored this influence in a cohort of HIV-1 infected individuals who were in long-term partnerships with other HIV-1 infected individuals. We found that individuals, who regularly engaged in unprotected receptive sexual intercourse with an HIV-1 infected viremic partner, displayed higher T cell responses to HIV proteins compared to those who were not regularly exposed to a viremic partner. None of the individuals within this study showed evidence of systemic super-infection. Exposure had limited impact on general activation or poly-functionality. These results are clearly of importance for HIV-1 infected individuals who chose to engage in unprotected sexual activity with other HIV-1 infected individuals. These data also reveal a more general mechanism that occurs in infectious diseases: immune responses to chronic viruses are influenced not only by the virus within the host, but also by exposure to the virus from without.
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Affiliation(s)
- Christian B Willberg
- Division of Experimental Medicine, Department of Medicine, University of California San Francisco, San Francisco, California, USA.
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