Prospective Surveillance for Cardiac Adverse Events in Healthy Adults Receiving Modified Vaccinia Ankara Vaccines: A Systematic Review

<div><h3>Background</h3><p>Vaccinia-associated myo/pericarditis was observed during the US smallpox vaccination (DryVax) campaign initiated in 2002. A highly-attenuated vaccinia strain, modified vaccinia Ankara (MVA) has been evaluated in clinical trials as a safer alternative to DryVax and as a vector for recombinant vaccines. Due to the lack of prospectively collected cardiac safety data, the US Food and Drug Administration required cardiac screening and surveillance in all clinical trials of MVA since 2004. Here, we report cardiac safety surveillance from 6 phase I trials of MVA vaccines.</p> <h3>Methods</h3><p>Four clinical research organizations contributed cardiac safety data using common surveillance methods in trials administering MVA or recombinant MVA vaccines to healthy participants. ‘Routine cardiac investigations’ (ECGs and cardiac enzymes obtained 2 weeks after injections of MVA or MVA-HIV recombinants, or placebo-controls), and ‘Symptom-driven cardiac investigations’ are reported. The outcome measure is the number of participants who met the CDC-case definition for vaccinia-related myo/pericarditis or who experienced cardiac adverse events from an MVA vaccine.</p> <h3>Results</h3><p>Four hundred twenty-five study participants had post-vaccination safety data analyzed, 382 received at least one MVA-containing vaccine and 43 received placebo; 717 routine ECGs and 930 cardiac troponin assays were performed. Forty-five MVA recipients (12%) had additional cardiac testing performed; 22 for cardiac symptoms, 19 for ECG/laboratory changes, and 4 for cardiac symptoms with an ECG/laboratory change. No participant had evidence of symptomatic or asymptomatic myo/pericarditis meeting the CDC-case definition and judged to be related to an MVA vaccine.</p> <h3>Conclusions</h3><p>Prospective surveillance of MVA recipients for myo/pericarditis did not detect cardiac adverse reactions in 382 study participants.</p> <h3>Trial Registration</h3><p>ClinicalTrials.gov <a href="http://clinicaltrials.gov/ct2/results?term=NCT00082446">NCT00082446</a> <a href="http://clinicaltrials.gov/ct2/results?term=NCT003766090">NCT003766090</a> <a href="http://clinicaltrials.gov/ct2/results?term=NCT00252148">NCT00252148</a> <a href="http://clinicaltrials.gov/ct2/results?term=NCT00083603">NCT00083603</a> <a href="http://clinicaltrials.gov/ct2/results?term=NCT00301184">NCT00301184</a> <a href="http://clinicaltrials.gov/ct2/results?term=NCT00428337">NCT00428337</a></p> </div

New onset ECG changes from routine and symptom-driven cardiac investigations.

a<p>p-values are calculated from Fisher’s exact test for association between variable and onset.</p>b<p>Left ventricular hypertrophy.</p

Cross-sectional frequency of solicited, self-reported symptoms suggestive of myo/pericarditis at visits 2 weeks post-vaccination/boost.

a<p>total number of participants who received: MVA = 382; placebo = 43.</p>b<p>expressed in mean ± standard deviation; for participants who had multiple reports of a given symptom, the minimum number of days post-vaccination and maximum duration of symptoms were used.</p>c<p>palpitations and flu-like symptoms not collected for SLU-DMID study.</p><p>n/a = not applicable.</p

Overview of clinical trial designs.

<p>Schema for each of the 6 clinical trials with prospective cardiac safety assessments included in this report, A) US Military HIV Research Program study [NCT00376090] <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0054407#pone.0054407-Currier1" target="_blank">[30]</a>, B) National Institutes of Health Division of Microbiology and Infectious Disease/St. Louis University study [NCT00082446] <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0054407#pone.0054407-Frey1" target="_blank">[11]</a>, C) Aaron Diamond AIDS Research Center/International AIDS Vaccine Initiative study [NCT00252148] <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0054407#pone.0054407-Vasan1" target="_blank">[31]</a>, D) HIV Vaccine Trials Network 055 study [NCT00083603] <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0054407#pone.0054407-Keefer1" target="_blank">[27]</a>, E) HIV Vaccine Trials Network 065 study [NCT00301184] <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0054407#pone.0054407-Goepfert1" target="_blank">[28]</a>, and F) HIV Vaccine Trials Network 067 study [NCT00428337] <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0054407#pone.0054407-Gorse1" target="_blank">[29]</a>. ‘Arrows’ indicate time of vaccination; ‘X’ indicates time of routine ECGs; ‘N’ indicates total number of study participants included in this analysis; ‘A:P’ indicates ratio of participants who received active vaccination (A) to placebo (P).</p

Demographics of participants with cardiac safety assessments.

<p>Demographics of participants with cardiac safety assessments.</p

Participant Flow.

<p>Flow diagram of participants screened, enrolled and followed with prospective cardiac safety assessments among the 6 trials included in this report. ‘MVA’ indicates MVA alone or an MVA-HIV recombinant candidate vaccine, whereas ‘Placebo’ was a buffered sterile saline solution.</p

9G4+ antibodies isolated from HIV-1 infected patients exhibit less Cardiolipin and ANA autoreactivity than 9G4+ isolated from SLE patients.

<p>Purified 9G4+ antibodies (from SLE [n=8] and HIV-1 infected patients [n=8]) were added to Cardiolipin (<b>A</b>) and HEp2 lysate (<b>B</b>) coated ELISA plates. Anti-IgG was used to detect antibody binding. (<b>B</b>) Cardiolipin IgG (GPLU/ml) and (<b>C</b>) ANA IgG (arbitrary units) were calculated based on manufacturer guidelines, and data were plotted. Each dot represents a sample. Significant differences between HIV and SLE patients were observed in 9G4+ antibody binding to cardiolipin and ANA as determined by Mann-Whitney test. (<b>C</b>) Slides coated with HEp-2 cells were incubated with patient antibodies, detected with FITC conjugated anti-IgG, and visualized with a fluorescence microscope. Dilutions of patient plasma were selected based on manufacturer guidelines while fractionated samples were used at 100 µg/ml. Representative images for unfractionated plasma, 9G4+ and 9G4- antibody fractions from an SLE patient and HIV patient are presented. </p

Auto-antigen microarray profiles of 9G4+ IgG isolated from HIV-infected patients.

<p>Plasma, 9G4+ and 9G4- antibodies were screened for IgG binding to 85 auto-antigens. Columns represent HIV samples, rows represent antigens and color maps to log₁₀ signal (gray indicates lower limit of detection, LLOD). Columns are organized by sample type (unfractionated plasma, 9G4+, 9G4-) and subject order within groups is the same for each type. Rows are clustered based on Euclidean distance to facilitate visualization. Antigens that resulted in no signal are listed to the right of the heat map. Antigens in red indicate higher 9G4+ binding relative to 9G4- based on a Wilcoxon signed-rank test at p<0.05. Average signal data where either the signal intensity was greater than 100 or the signal-to-noise ratio was greater than 2 were considered to be above the LLOD; these data were background-subtracted (based on PBS control per antigen) and then log₁₀ transformed.</p

9G4+ antibodies from HIV-1 infected patients bind apoptotic lymphocytes.

<p>Unfractionated serum from normal donors (n=16), SLE (n=21) and HIV- infected (n=57) were used in apoptotic binding assays. (<b>A</b>-<b>C</b>) The Jurkat Human T cell line was treated with camptothecin to induce apoptosis then incubated with patient serum. Serum binding to cells was detected using FITC- labeled 9G4 rat anti-human monoclonal antibody. Apoptotic Cell Gate was drawn around cells stained positive for viability dye, representing the dying cell population. (<b>C</b>) The shaded histogram represents cells incubated with PBS in the absence of patient serum. The thin-line represents the antibody binding from a normal serum donor and the Bold-line is representative of 9G4+ antibody binding from an HIV infected patient. (<b>D</b>) Data from all samples are plotted. The dashed-line represents the normal donor mean plus 2 standard deviations. Significance determined by Mann-Whitney test.</p

9G4+ antibodies purified from HIV- infected patients bind to HIV gp140 and neutralize HIV-1.

<p>9G4+ antibodies isolated from SLE patients (n=6) and PLWH (n=8) normalized to equal concentrations, were serially diluted in triplicate and added to ELISA plates coated with oligomeric YU2 gp140 (<b>A</b>) Influenza vaccine (<b>C</b>) or CMV lysate (<b>D</b>) and binding detected by anti-IgG. (<b>B</b>) 9G4+ antibodies were tested for inhibition of pseudotyped HIV-1 SF-162 infection of TZM-bl cells. Infectivity was measured by luciferase assay, and relative inhibitions were calculated after normalizing to internal controls. Each symbol represents the mean value of a patient. Significance determined by Mann-Whitney test.</p