[Show abstract][Hide abstract] ABSTRACT: The index case of the Ebola virus disease epidemic in West Africa is believed to have originated in Guinea. By June 2014, Guinea, Liberia, and Sierra Leone were in the midst of a full-blown and complex global health emergency. The devastating effects of this Ebola epidemic in West Africa put the global health response in acute focus for urgent international interventions. Accordingly, in October 2014, a World Health Organization high-level meeting endorsed the concept of a phase 2/3 clinical trial in Liberia to study Ebola vaccines. As a follow-up to the global response, in November 2014, the Government of Liberia and the US Government signed an agreement to form a research partnership to investigate Ebola and to assess intervention strategies for treating, controlling, and preventing the disease in Liberia. This agreement led to the establishment of the Joint Liberia-US Partnership for Research on Ebola Virus in Liberia as the beginning of a long-term collaborative partnership in clinical research between the two countries. In this article, we discuss the methodology and related challenges associated with the implementation of the Ebola vaccines clinical trial, based on a double-blinded randomized controlled trial, in Liberia.
[Show abstract][Hide abstract] ABSTRACT: Ionizing irradiation is used routinely to induce myeloablation and immunosuppression. However, it has not been possible to evaluate the extent of ablation without invasive biopsy. For lymphoid recovery, peripheral blood lymphocytes (PBLs) have been used for analysis, but they represent< 2% of cells in lymphoid tissues (LTs). Using a combination of single-photon emission computed tomography(SPECT) and a radiotracer ((99m)Tc-labeled rhesus IgG1anti-CD4R1(Fab')2), we sequentially imaged CD4+ cell recovery in rhesus macaques following total body irradiation(TBI) and reinfusion of vector transduced, autologous CD34+ cells. Our results present for the first time a sequential, real time, non-invasive method to evaluate CD4+ cell recovery. Importantly, despite myeloablation of circulating leukocytes following TBI, total depletion of CD4+ lymphocytes in LTs such as the spleen is not achieved. The impact of TBI on LTs and PBLs is discordant, in which as few as 32.4% of CD4+ cells were depleted from the spleen. In addition, despite full lymphocyte recovery in the spleen and PB, lymph nodes (LNs) have sub-optimal recovery. This highlights concerns about residual disease, endogenous contributions to recovery, and residual LT damage following ionizing irradiation. Such methodologies also have direct application to immunosuppressive therapy and other immunosuppressive disorders, such as those associated with viral monitoring.
[Show abstract][Hide abstract] ABSTRACT: Hemagglutination inhibition (HAI) antibody responses to anti-influenza hyperimmune intravenous immunoglobulin (hIVIG) were
characterized. Thirty-one influenza patients (2013-2014) were randomized to 0.25 G/kg of hIVIG (n=16) or placebo (n=15). For
hIVIG recipients the ratio of geometric mean titers (1-hour post-infusion/pre-infusion) was 4.00 (95% CI=2.61-6.13) for influenza
A(H1N1)pdm09 and 1.76 (95% CI=1.33-2.32) for A(H3N2) and influenza B. Among patients with A(H1N1)pdm09 virus, ratios for hIVIG
(n=9) versus placebo (n=8), were higher 1-hour post-infusion [3.9 (95% CI: 2.3-6.7)] and sustained through day 3 [2.0 (95%
CI: 1.0-4.0)]. hIVIG administration significantly increases HAI titer levels among influenza patients supporting a clinical
No preview · Article · Sep 2015 · The Journal of Infectious Diseases
[Show abstract][Hide abstract] ABSTRACT: Background:
Data from randomized trials are lacking on the benefits and risks of initiating antiretroviral therapy in patients with asymptomatic human immunodeficiency virus (HIV) infection who have a CD4+ count of more than 350 cells per cubic millimeter.
We randomly assigned HIV-positive adults who had a CD4+ count of more than 500 cells per cubic millimeter to start antiretroviral therapy immediately (immediate-initiation group) or to defer it until the CD4+ count decreased to 350 cells per cubic millimeter or until the development of the acquired immunodeficiency syndrome (AIDS) or another condition that dictated the use of antiretroviral therapy (deferred-initiation group). The primary composite end point was any serious AIDS-related event, serious non-AIDS-related event, or death from any cause.
A total of 4685 patients were followed for a mean of 3.0 years. At study entry, the median HIV viral load was 12,759 copies per milliliter, and the median CD4+ count was 651 cells per cubic millimeter. On May 15, 2015, on the basis of an interim analysis, the data and safety monitoring board determined that the study question had been answered and recommended that patients in the deferred-initiation group be offered antiretroviral therapy. The primary end point occurred in 42 patients in the immediate-initiation group (1.8%; 0.60 events per 100 person-years), as compared with 96 patients in the deferred-initiation group (4.1%; 1.38 events per 100 person-years), for a hazard ratio of 0.43 (95% confidence interval [CI], 0.30 to 0.62; P<0.001). Hazard ratios for serious AIDS-related and serious non-AIDS-related events were 0.28 (95% CI, 0.15 to 0.50; P<0.001) and 0.61 (95% CI, 0.38 to 0.97; P=0.04), respectively. More than two thirds of the primary end points (68%) occurred in patients with a CD4+ count of more than 500 cells per cubic millimeter. The risks of a grade 4 event were similar in the two groups, as were the risks of unscheduled hospital admissions.
The initiation of antiretroviral therapy in HIV-positive adults with a CD4+ count of more than 500 cells per cubic millimeter provided net benefits over starting such therapy in patients after the CD4+ count had declined to 350 cells per cubic millimeter. (Funded by the National Institute of Allergy and Infectious Diseases and others; START ClinicalTrials.gov number, NCT00867048.).
Full-text · Article · Aug 2015 · New England Journal of Medicine
[Show abstract][Hide abstract] ABSTRACT: Despite successfully suppressed viremia by treatment, patients with high levels of biomarkers of coagulation/inflammation are at an increased risk of developing non-AIDS defining serious illnesses such as cardiovascular diseases. Thus, there is a relationship between persistent immune activation and coagulation and inflammation, although the mechanisms are poorly understood. Platelets play an important role in this process. Although interactions between platelets and elements of the innate immune system, such as monocytes, are well described, little is known about the interaction between platelets and the adaptive immune system.
We investigated the interaction of a component of the coagulation system, platelets, and the adaptive immune system, T cells.
Healthy controls and combination antiretroviral therapy (cART) treated HIV infected patients with viral loads of less than 40 copies/ml for more than 15 months were analysed for platelet-T cell conjugate formation.
Platelets can form conjugates with T cells and were preferentially seen in CD4 and CD8 T cell subsets with more differentiated phenotypes [memory, memory/effector and terminal effector memory (TEM)]. Compared with healthy controls, these conjugates in patients with HIV infection were more frequent and more often composed of activated platelets (CD42bCD62P) and were significantly associated with the D-dimer serum levels.
These data support a model in which platelet-T cell conjugates may play a critical role in the fast recruitment of antigen-experienced T cells to the place of injury. This mechanism can contribute in maintaining a state of coagulation/inflammation observed in these patients contributing to the pathology of the disease.
Full-text · Article · May 2015 · AIDS (London, England)
[Show abstract][Hide abstract] ABSTRACT: More than 26 000 cases of Ebola virus disease (EVD) have been reported in western Africa, with high mortality. Several patients have been medically evacuated to hospitals in the United States and Europe. Detailed clinical data are limited on the clinical course and management of patients with EVD outside western Africa.
To describe the clinical characteristics and management of a cluster of patients with EVD, including the first cases of Ebola virus (EBOV) infection acquired in the United States.
Retrospective clinical case series.
Three U.S. hospitals in September and October 2014.
First imported EVD case identified in the United States and 2 secondary EVD cases acquired in the United States in critical care nurses who cared for the index case patient.
Clinical recovery, EBOV RNA level, resolution of Ebola viremia, survival with discharge from hospital, or death.
The index patient had high EBOV RNA levels, developed respiratory and renal failure requiring critical care support, and died. Both patients with secondary EBOV infection had nonspecific signs and symptoms and developed moderate illness; EBOV RNA levels were moderate, and both patients recovered.
Both surviving patients received uncontrolled treatment with multiple investigational agents, including convalescent plasma, which limits generalizability of the results.
Early diagnosis, prompt initiation of supportive medical care, and moderate clinical illness likely contributed to successful outcomes in both survivors. The inability to determine the potential benefit of investigational therapies and the effect of patient-specific factors that may have contributed to less severe illness highlight the need for controlled clinical studies of these interventions, especially in the setting of a high level of supportive medical care.
Full-text · Article · May 2015 · Annals of internal medicine
[Show abstract][Hide abstract] ABSTRACT: The ongoing outbreak of Ebola in West Africa has raised a general awareness that at present there are no Ebola-specific medical countermeasures (MCMs) with proven effectiveness. This paper recapitulates discussions held at the 6th International Filovirus Symposium in March 2014 as well as the subsequent design of a randomized clinical trial design for treating Ebola virus-infected patients evacuated from West Africa to the United States. A number of different drugs or biologics were critically reviewed and 3 different postexposure strategies were identified as being farthest along in development; passive immunotherapy with monoclonal antibodies, postexposure vaccination with constructs involving viral vectors (such as vesicular stomatitis virus), and antisense compounds directly targeting the viral genome such as modified phosphorodiamidate morpholino oligomer-based compounds and small interfering RNA products. At the time of the meetings, there were no investigational new drugs (INDs) in place for the candidate MCMs. Developers and sponsors of these candidate products were strongly encouraged to prepare pre-IND packets and submit pre-IND meeting requests to the Food and Drug Administration. Some of these investigational products have already been used under emergency authorizations to treat patients in Africa as well as patients evacuated to the United States or Western Europe.
Published by Oxford University Press on behalf of the Infectious Diseases Society of America 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.
No preview · Article · May 2015 · The Journal of Infectious Diseases
[Show abstract][Hide abstract] ABSTRACT: Background The current Ebola virus disease (EVD) outbreak has resulted in more than 24,000 cases and 10,000 deaths. We present a preliminary report from two phase 1 trials of an attenuated, replication-competent, recombinant vesicular stomatitis virus (rVSV)-based vaccine candidate to prevent EVD. Methods We conducted two phase 1, placebo-controlled, double-blind, dose-escalation trials of an rVSV-based vaccine candidate expressing the glycoprotein of a Zaire strain of Ebola virus (ZEBOV). A total of 26 adults at each site (52 participants in all) were consecutively enrolled into groups of 13 each. Three volunteers in each group received an intramuscular injection of placebo, and 10 received an intramuscular injection of the rVSV-ZEBOV vaccine at a dose of either 3 million plaque-forming units (PFU) or 20 million PFU. Safety and immunogenicity were assessed for the 28 days after vaccination. Results The most common adverse events were injection-site pain, myalgia, and fatigue; no events resulted in withdrawal from the study. Transient VSV viremia was noted in all the vaccine recipients. By day 28, all the vaccine recipients had seroconversion as assessed by an enzyme-linked immunosorbent assay (ELISA) against the glycoprotein of the ZEBOV-Kikwit strain. At day 28, geometric mean titers of antibodies against ZEBOV glycoprotein were higher in the group receiving 20 million PFU than in the group receiving 3 million PFU, as assessed by ELISA (geometric mean antibody titer, 4079 vs. 1300; P<0.001) and by pseudovirion neutralization assay (geometric mean antibody titer, 441 vs. 223; P=0.07). Conclusions No safety concerns were identified after a single administration of the rVSV-ZEBOV vaccine candidate, and anti-Ebola immune responses were identified in all the volunteers. VSV viremia was detected but was of limited duration. These preliminary results support the further development of the vaccine dose of 20 million PFU. (Funded by the National Institutes of Health and others; rVSVΔG-ZEBOV-GP ClinicalTrials.gov numbers, NCT02269423 and NCT02280408 .).
No preview · Article · Apr 2015 · New England Journal of Medicine
[Show abstract][Hide abstract] ABSTRACT: Safe and effective vaccines and drugs are needed for the prevention and treatment of Ebola virus disease, including following a potentially high-risk exposure such as a needlestick.
To assess response to postexposure vaccination in a health care worker who was exposed to the Ebola virus.
Case report of a physician who experienced a needlestick while working in an Ebola treatment unit in Sierra Leone on September 26, 2014. Medical evacuation to the United States was rapidly initiated. Given the concern about potentially lethal Ebola virus disease, the patient was offered, and provided his consent for, postexposure vaccination with an experimental vaccine available through an emergency Investigational New Drug application. He was vaccinated on September 28, 2014.
The vaccine used was VSVΔG-ZEBOV, a replicating, attenuated, recombinant vesicular stomatitis virus (serotype Indiana) whose surface glycoprotein gene was replaced by the Zaire Ebola virus glycoprotein gene. This vaccine has entered a clinical trial for the prevention of Ebola in West Africa.
The vaccine was administered 43 hours after the needlestick occurred. Fever and moderate to severe symptoms developed 12 hours after vaccination and diminished over 3 to 4 days. The real-time reverse transcription polymerase chain reaction results were transiently positive for vesicular stomatitis virus nucleoprotein gene and Ebola virus glycoprotein gene (both included in the vaccine) but consistently negative for Ebola virus nucleoprotein gene (not in the vaccine). Early postvaccination cytokine secretion and T lymphocyte and plasmablast activation were detected. Subsequently, Ebola virus glycoprotein-specific antibodies and T cells became detectable, but antibodies against Ebola viral matrix protein 40 (not in the vaccine) were not detected.
It is unknown if VSVΔG-ZEBOV is safe or effective for postexposure vaccination in humans who have experienced a high-risk occupational exposure to the Ebola virus, such as a needlestick. In this patient, postexposure vaccination with VSVΔG-ZEBOV induced a self-limited febrile syndrome that was associated with transient detection of the recombinant vesicular stomatitis vaccine virus in blood. Strong innate and Ebola-specific adaptive immune responses were detected after vaccination. The clinical syndrome and laboratory evidence were consistent with vaccination response, and no evidence of Ebola virus infection was detected.
No preview · Article · Mar 2015 · JAMA The Journal of the American Medical Association
[Show abstract][Hide abstract] ABSTRACT: Background
Data from prospectively planned cohort studies on risk of major clinical outcomes and prognostic factors for patients with influenza A(H1N1)pdm09 virus are limited. In 2009, in order to assess outcomes and evaluate risk factors for progression of illness, two cohort studies were initiated: FLU 002 in outpatients and FLU 003 in hospitalized patients.
Methods and Findings
Between October 2009 and December 2012, adults with influenza-like illness (ILI) were enrolled; outpatients were followed for 14 days and inpatients for 60 days. Disease progression was defined as hospitalization and/or death for outpatients, and hospitalization for >28 days, transfer to intensive care unit (ICU) if enrolled from general ward, and/or death for inpatients. Infection was confirmed by RT-PCR. 590 FLU 002 and 392 FLU 003 patients with influenza A (H1N1)pdm09 were enrolled from 81 sites in 17 countries at 2 days (IQR 1–3) and 6 days (IQR 4–10) following ILI onset, respectively. Disease progression was experienced by 29 (1 death) outpatients (5.1%; 95% CI: 3.4–7.2%) and 80 inpatients [death (32), hospitalization >28 days (43) or ICU transfer (20)] (21.6%; 95% CI: 17.5–26.2%). Disease progression (death) for hospitalized patients was 53.1% (26.6%) and 12.8% (3.8%), respectively, for those enrolled in the ICU and general ward. In pooled analyses for both studies, predictors of disease progression were age, longer duration of symptoms at enrollment and immunosuppression. Patients hospitalized during the pandemic period had a poorer prognosis than in subsequent seasons.
Patients with influenza A(H1N1)pdm09, particularly when requiring hospital admission, are at high risk for disease progression, especially if they are older, immunodeficient, or admitted late in infection. These data reinforce the need for international trials of novel treatment strategies for influenza infection and serve as a reminder of the need to monitor the severity of seasonal and pandemic influenza epidemics globally.
ClinicalTrials.gov Identifiers: FLU 002- NCT01056354, FLU 003- NCT01056185.
[Show abstract][Hide abstract] ABSTRACT: Objectives: After DNA or RNA virus infection, cytosolic foreign DNA or RNA derived from the infecting viruses is recognized by intracellular pathogen recognition receptors (PRRs) and induces activation of the innate immune system. Transfection of DNA has been used as an experimental model for DNA virus-mediated innate responses. We have previously reported that DNA transfection preferentially induces Type-III IFN (IFN-λ1) rather than Type-I IFN (IFN-β). In this study, we compared the DNA-mediated immune response between healthy controls and HIV-1 infected patients with undetectable viral loads and assessed potential innate immune responses in these patients.
Methods: The study consisted of 50 HIV-1 negative healthy donors, 46 patients on combination antiretroviral therapy with HIV-1 viral loads <50 copies/ml and 7 long term non-progressors (LTNPs). PBMCs were isolated from whole blood using Ficoll-Paque. DNA transfection was performed using Lipofectamine 2000. After 22 hours incubation, total cellular RNA was extracted and real time RT-PCR was performed to determine gene expression level of IFN-λ1, IFN-β and RANTES. Gene induction was compared by fold change.
Results: Baseline levels of endogenous gene expression of IFN-λ1, IFN-β and RANTES in HIV-1 patients were higher than in controls. Following DNA transfection, both HIV infected patients and healthy controls induced gene induction, however, the induction in HIV-1 patients was at a significantly lower level compared to uninfected controls.
Conclusion: HIV-1 treated patients with undetectable viral loads have lower levels of innate immune responses via cytosolic DNA sensing systems. This may be caused by persistent immune activation.
Full-text · Article · Jun 2014 · Journal of AIDS & Clinical Research