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1.
N Engl J Med ; 385(15): e63, 2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34614335
4.
N Engl J Med ; 385(14): e59, 2021 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-34587392
6.
N Engl J Med ; 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34551225

RESUMO

BACKGROUND: At interim analysis in a phase 3, observer-blinded, placebo-controlled clinical trial, the mRNA-1273 vaccine showed 94.1% efficacy in preventing coronavirus disease 2019 (Covid-19). After emergency use of the vaccine was authorized, the protocol was amended to include an open-label phase. Final analyses of efficacy and safety data from the blinded phase of the trial are reported. METHODS: We enrolled volunteers who were at high risk for Covid-19 or its complications; participants were randomly assigned in a 1:1 ratio to receive two intramuscular injections of mRNA-1273 (100 µg) or placebo, 28 days apart, at 99 centers across the United States. The primary end point was prevention of Covid-19 illness with onset at least 14 days after the second injection in participants who had not previously been infected with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The data cutoff date was March 26, 2021. RESULTS: The trial enrolled 30,415 participants; 15,209 were assigned to receive the mRNA-1273 vaccine, and 15,206 to receive placebo. More than 96% of participants received both injections, 2.3% had evidence of SARS-CoV-2 infection at baseline, and the median follow-up was 5.3 months in the blinded phase. Vaccine efficacy in preventing Covid-19 illness was 93.2% (95% confidence interval [CI], 91.0 to 94.8), with 55 confirmed cases in the mRNA-1273 group (9.6 per 1000 person-years; 95% CI, 7.2 to 12.5) and 744 in the placebo group (136.6 per 1000 person-years; 95% CI, 127.0 to 146.8). The efficacy in preventing severe disease was 98.2% (95% CI, 92.8 to 99.6), with 2 cases in the mRNA-1273 group and 106 in the placebo group, and the efficacy in preventing asymptomatic infection starting 14 days after the second injection was 63.0% (95% CI, 56.6 to 68.5), with 214 cases in the mRNA-1273 group and 498 in the placebo group. Vaccine efficacy was consistent across ethnic and racial groups, age groups, and participants with coexisting conditions. No safety concerns were identified. CONCLUSIONS: The mRNA-1273 vaccine continued to be efficacious in preventing Covid-19 illness and severe disease at more than 5 months, with an acceptable safety profile, and protection against asymptomatic infection was observed. (Funded by the Biomedical Advanced Research and Development Authority and the National Institute of Allergy and Infectious Diseases; COVE ClinicalTrials.gov number, NCT04470427.).

8.
Clin Infect Dis ; 2021 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-34363462

RESUMO

The impact of COVID19 vaccination on viral characteristics of breakthrough infections is unknown. In this prospective cohort study, incidence of SARS-CoV-2 infection decreased following vaccination. Although asymptomatic positive tests were observed following vaccination, higher cycle thresholds, repeat negative tests and inability to culture virus raises questions about their clinical significance.

11.
Med (N Y) ; 2021 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-34414383

RESUMO

BACKGROUND: T cells control viral infection and promote vaccine durability and in COVID-19 associate with mild disease. We investigated whether prior Measles-Mumps-Rubella (MMR) or Tetanus-Diptheria-Pertussis (Tdap) vaccination elicit cross-reactive T cells that mitigate COVID-19. METHODS: Antigen presenting cells (APC) loaded ex vivo with SARS-CoV-2, MMR or Tdap antigens and autologous T cells from COVID-19 convalescent and uninfected individuals, and COVID-19 mRNA vaccinated donors were co-cultured and T cell activation and phenotype were detected by IFN-γ ELISpot assays and flow cytometry. ELISA assays and validation studies identified the APC-derived cytokine(s) driving T cell activation. TCR clonotyping and scRNA-seq identified cross-reactive T cells and their transcriptional profile. A propensity-weighted analysis of COVID-19 patients estimated the effects of MMR and Tdap vaccination on COVID-19 outcomes. FINDINGS: High correlation was observed between T cell responses to SARS-CoV-2 (Spike-S1 and Nucleocapsid) and MMR and Tdap proteins in COVID-19 convalescent and vaccinated individuals. The overlapping T cell population contained an effector memory T cell subset (TEMRA) implicated in protective, anti-viral immunity and their detection required APC-derived IL-15, known to sensitize T cells to activation. Cross-reactive TCR repertoires detected in antigen-experienced T cells recognizing SARS-CoV-2, MMR and Tdap epitopes had TEMRA features. Indices of disease severity were reduced in MMR or Tdap vaccinated individuals by 32-38% and 20-23% respectively, among COVID-19 patients. CONCLUSIONS: Tdap and MMR memory T cells reactivated by SARS-CoV-2 may provide protection against severe COVID-19 disease. FUNDING: National Institutes of Health (R01HL065095, R01AI152522, R01NS097719), donation from Barbara and Amos Hostetter and the Chleck Foundation.

12.
Arthritis Rheumatol ; 73(10): e60-e75, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34346564

RESUMO

OBJECTIVE: To provide guidance to rheumatology providers on the use of coronavirus disease 2019 (COVID-19) vaccines for patients with rheumatic and musculoskeletal diseases (RMDs). METHODS: A task force was assembled that included 9 rheumatologists/immunologists, 2 infectious disease specialists, and 2 public health physicians. After agreeing on scoping questions, an evidence report was created that summarized the published literature and publicly available data regarding COVID-19 vaccine efficacy and safety, as well as literature for other vaccines in RMD patients. Task force members rated their agreement with draft consensus statements on a 9-point numerical scoring system, using a modified Delphi process and the RAND/University of California Los Angeles Appropriateness Method, with refinement and iteration over 2 sessions. Consensus was determined based on the distribution of ratings. RESULTS: Despite a paucity of direct evidence, 74 draft guidance statements were developed by the task force and agreed upon with consensus to provide guidance for use of the COVID-19 vaccines in RMD patients and to offer recommendations regarding the use and timing of immunomodulatory therapies around the time of vaccination. CONCLUSION: These guidance statements, made in the context of limited clinical data, are intended to provide direction to rheumatology health care providers on how to best use COVID-19 vaccines and to facilitate implementation of vaccination strategies for RMD patients.


Assuntos
Vacinas contra COVID-19/uso terapêutico , COVID-19/prevenção & controle , Doenças Musculoesqueléticas , Doenças Reumáticas , Reumatologia , Humanos , Estados Unidos
16.
Vaccine ; 39(33): 4641-4650, 2021 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-34229888

RESUMO

BACKGROUND: Eliciting durable humoral immunity with sufficient breadth and magnitude is important for HIV-1 vaccine design. The HVTN 114 vaccine trial evaluated different boost regimens administered after a 7-year rest period in participants previously enrolled in HVTN 205, who received either three MVA/HIV62B (MMM) or two DNA and two MVA/HIV62B (DDMM) injections; both vaccines expressed multiple HIV-1 antigens in non-infectious virus-like-particles. The primary objective of HVTN 114 was to assess the impact of a heterologous gp120 protein AIDSVAX B/E boost on the magnitude, breadth and durability of vaccine-induced immune responses. METHODS: We enrolled 27 participants from HVTN 205 into five groups. Eight participants who previously received MMM were randomized and boosted with either MVA/HIV62B alone (T1; n = 4) or MVA/HIV62B and AIDSVAX B/E (T2; n = 4). Nineteen participants who received DDMM were randomized and boosted with MVA/HIV62B alone (T3; n = 6), MVA/HIV62B and AIDSVAX B/E (T4; n = 6), or AIDSVAX B/E alone (T5; n = 7). Boosts were at months 0 and 4. Participants were followed for safety and immunogenicity for 10 months and were pooled for analysis based on the regimen: MVA-only (T1 + T3), MVA + AIDSVAX (T2 + T4), and AIDSVAX-only (T5). RESULTS: All regimens were safe and well-tolerated. Prior to the boost vaccination, binding antibody and CD4+T-cell responses were observed 7 years after HVTN 205 vaccinations. Late boosting with AIDSVAX, with or without MVA, resulted in high binding antibody responses to gp120 and V1V2 epitopes, with increased magnitude and breadth compared to those observed in HVTN 205. Late boosting with MVA, with or without AIDSVAX, resulted in increased gp140 and gp41 antibody responses and higher CD4+T-cell responses to Env and Gag. CONCLUSIONS: Late boosting with AIDSVAX, alone or in combination with MVA, can broaden binding antibody responses and increase T-cell responses even years following the original MVA/HIV62B with or without DNA-priming vaccine.


Assuntos
Vacinas contra a AIDS , Infecções por HIV , HIV-1 , Vacinas de DNA , Anticorpos Anti-HIV , Infecções por HIV/prevenção & controle , Humanos , Imunização Secundária
19.
J Appl Lab Med ; 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34196711

RESUMO

BACKGROUND: Serological testing provides a record of prior infection with SARS-CoV-2, but assay performance requires independent assessment. METHODS: We evaluated three commercial (Roche Diagnostics pan-IG, Epitope Diagnostics IgM and IgG) and two non-commercial (Simoa, Ragon/MGH IgG) immunoassays against 1083 unique samples that included 251 PCR positive and 832 pre-pandemic samples. RESULTS: The Roche assay registered the highest specificity 99.6% (3/832 false positives), the Ragon/MGH assay 99.5% (4/832), the primary Simoa assay model 99.0% (8/832), and the Epitope IgG and IgM 99.0 (8/830) and 99.5% (4/830) respectively. Overall sensitivities for the Simoa, Roche pan-IG, Epitope IgG, Ragon/MGH IgG, and Epitope IgM were 92.0%, 82.9%, 82.5%, 64.5% and 47.0% respectively. The Simoa immunoassay demonstrated the highest sensitivity among samples stratified by days post symptom onset (PSO), < 8 days PSO (57.69%) 8-14 days PSO (93.51%), 15-21 days PSO (100%), and > 21 days PSO (95.18%). CONCLUSIONS: All assays demonstrated high to very high specificities while sensitivities were variable across assays.

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