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Background: Though Modified Vaccinia Ankara - Bavarian Nordic (MVA-BN®). vaccination is approved for smallpox and monkeypox prevention, immunological persistence and booster effects remain undescribed.Methods: Participants naïve to smallpox vaccination were randomized to 1 dose MVA-BN (1×MVA, N = 181), 2 doses MVA-BN (2×MVA, N = 183), or placebo (N = 181). Participants with previous smallpox vaccination received 1 MVA-BN booster (HSPX+, N = 200). Subsets of the formerly naïve groups (∼75 each) received an MVA-BN booster 2 years later.Results: Neutralizing antibody (nAb) geometric mean titers (GMTs) increased from 1.1 (baseline, both naïve groups) to 7.2 and 7.5 (Week 4, 1×MVA and 2×MVA, respectively), and further to 45.6 (Week 6, 2×MVA after second vaccination). In HSPX+, nAb GMT rapidly increased from 21.6 (baseline) to 175.1 (Week 2). At 2 years, GMTs for 1×MVA, 2×MVA, and HSPX+ were 1.1, 1.3, and 10.3, respectively. After boosting in the previously naïve groups, nAb GMTs increased rapidly in 2 weeks to 80.7 (1×MVA) and 125.3 (2×MVA), higher than after primary vaccination and comparable to boosted HSPX+ subjects. Six months after boosting, GMTs were 25.6 (1×MVA) and 49.3 (2×MVA). No safety concerns were identified.Conclusion: Anamnestic responses without sustained high nAb titers support presence of durable immunological memory following MVA-BN immunization. [ABSTRACT FROM AUTHOR]

After a pivotal year for the collective proceedings regime in England and Wales in 2021, this article explores the further developments coming out of the judgment of the collective proceedings orders (CPO) application by Malcolm McLaren. It also looks ahead, from the time of writing in March 2022, at the key issues anticipated in the forthcoming year, in particular the management of collective proceedings beyond certification. [ABSTRACT FROM AUTHOR]

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a worldwide pandemic. Here, we present non-human primate immunogenicity and protective efficacy data generated with the capsid virus-like particle (cVLP)-based vaccine ABNCoV2 that has previously demonstrated immunogenicity in mice. In rhesus macaques, a single vaccination with either 15 or 100 μg ABNCoV2 induced binding and neutralizing antibodies in a dose-dependent manner, at levels comparable to those measured in human convalescents. A second vaccine administration led to a >50-fold increase in neutralizing antibodies, with 2-log higher mean levels in the 100-μg ABNCoV2 group compared with convalescent samples. Upon SARS-CoV-2 challenge, a significant reduction in viral load was observed for both vaccine groups relative to the challenge control group, with no evidence of enhanced disease. Remarkably, neutralizing antibody titers against an original SARS-CoV-2 isolate and against variants of concern were comparable, indicating a potential for broad protection afforded by ABNCoV2, which is currently in clinical testing. [ABSTRACT FROM AUTHOR]

Poxviruses such as the causative agent of smallpox have developed multiple strategies to suppress immune responses, including the suppression of DC activation. Since poxviruses are large DNA viruses, we hypothesized that their detection by DCs may involve the endosomal DNA recognition receptor TLR9. Indeed, we have shown here that DC recognition of ectromelia virus (ECTV), the causative agent of mousepox, completely depended on TLR9. The importance of TLR9 was highlighted by the fact that mice lacking TLR9 showed drastically increased susceptibility to infection with ECTV. In contrast, we found that the strongly attenuated poxvirus modified vaccinia virus Ankara (MVA) activated DCs by both TLR9-dependent and -independent pathways. We therefore tested whether we could use the broader induction of immune responses by MVA to protect mice from a lethal infection with ECTV. Indeed, MVA given at the same time as a lethal dose of ECTV protected mice from death. Importantly, MVA also rescued TLR9-deficient mice if administered 2 full days after an otherwise lethal infection with ECTV. Therefore, these data suggest an essential role for TLR9 in the defense against poxviruses. In addition, postexposure application of MVA may protect against lethal poxvirus infection., Introduction Poxviruses, including variola virus (VARV), the causative agent of smallpox, are highly pathogenic dsDNA viruses. It is proposed that smallpox has caused more death within the human population than [...]

Background: There are limited data regarding immunological correlates of protection for the modified vaccinia Ankara (MVA) smallpox vaccine.Methods: A total of 523 vaccinia-naive subjects were randomized to receive 2 vaccine doses, as lyophilized MVA given subcutaneously, liquid MVA given subcutaneously (liquid-SC group), or liquid MVA given intradermally (liquid-ID group) 28 days apart. For a subset of subjects, antibody-dependent cellular cytotoxicity (ADCC), interferon-γ release enzyme-linked immunospot (ELISPOT), and protein microarray antibody-binding assays were conducted. Protein microarray responses were assessed for correlations with plaque reduction neutralization titer (PRNT), enzyme-linked immunosorbent assay, ADCC, and ELISPOT results.Results: MVA elicited significant microarray antibody responses to 15 of 224 antigens, mostly virion membrane proteins, at day 28 or 42, particularly WR113/D8L and WR101H3L. In the liquid-SC group, responses to 9 antigens, including WR113/D8L and WR101/H3L, correlated with PRNT results. Three were correlated in the liquid-ID group. No significant correlations were observed with ELISPOT responses. In the liquid-ID group, WR052/F13L, a membrane glycoprotein, correlated with ADCC responses.Conclusions: MVA elicited antibodies to 15 vaccinia strain antigens representing virion membrane. Antibody responses to 2 proteins strongly increased and significantly correlated with increases in PRNT. Responses to these proteins are potential correlates of protection and may serve as immunogens for future vaccine development.Clinical Trials Registration: NCT00914732. [ABSTRACT FROM AUTHOR]

Background: Respiratory syncytial virus (RSV) is a major cause of severe respiratory disease in young children and the elderly. Protective immunity is not generated after repeated infections, but vaccination may hopefully prove effective.Methods: This phase 2 clinical study investigated a multivalent RSV vaccine (MVA-BN-RSV) designed to induce broad antibody and cellular immune responses by encoding RSV surface proteins F, G (for both A and B subtypes), and internal antigens (M2, N). This study evaluated the immune response in adults aged ≥55 years to identify the optimal MVA-BN-RSV dose and vaccination schedule.Results: A single dose increased the levels of neutralizing (plaque reduction neutralization test to RSV A and B) and total (IgG and IgA ELISA) antibodies (1.6 to 3.4-fold increase from baseline) and induced a broad Th1-biased cellular immune response (interferon-γ ELISPOT) to all 5 vaccine inserts (5.4 to 9.7-fold increases). Antibody responses remained above baseline for 6 months. A 12-month booster dose elicited a booster effect in antibody and T-cell responses (up to 2.8-fold from preboost levels). No drug-related serious adverse events were reported.Conclusions: MVA-BN-RSV induces a broad immune response that persists at least 6 months and can be boosted at 12 months, without significant safety findings.Clinical Trials Registration: NCT02873286. [ABSTRACT FROM AUTHOR]