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1.
J Infect Dis ; 230(3): e591-e600, 2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-38513368

RESUMEN

BACKGROUND: Solid organ transplant recipients (SOTRs) are at high risk for severe COVID-19. METHODS: This open-label, phase 3b trial evaluated mRNA-1273 in 137 kidney and 77 liver SOTRs and 20 immunocompetent participants. In part A, SOTRs received three 100-µg doses of mRNA-1273; immunocompetent participants received 2 doses. In part B, an additional 100-µg dose was offered ≥4 months after the primary series. Here, we report interim trial results. RESULTS: mRNA-1273 was well-tolerated in SOTRs. Four serious adverse events were considered vaccine related by the investigator in 3 SOTRs with preexisting comorbidities. No vaccine-related biopsy-proven organ rejection events or deaths were reported. mRNA-1273 elicited modest neutralizing antibody responses after dose 2 and improved responses after dose 3 in SOTRs. Post-dose 3 responses among liver SOTRs were comparable to post-dose 2 responses in immunocompetent participants. Post-additional dose responses were increased in SOTRs, regardless of primary series vaccination. In liver SOTRs, post-additional dose responses were ∼3-fold higher versus post-dose 2 but lower than immunocompetent participant responses. Most kidney SOTRs received multiple immunosuppressants and had reduced antibody responses versus liver SOTRs. CONCLUSIONS: mRNA-1273 was well-tolerated, and dose 3 and the additional dose improved antibody responses among SOTRs. CLINICAL TRIALS REGISTRATION: NCT04860297.


Asunto(s)
Vacuna nCoV-2019 mRNA-1273 , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Vacunas contra la COVID-19 , COVID-19 , Trasplante de Órganos , SARS-CoV-2 , Receptores de Trasplantes , Humanos , Vacuna nCoV-2019 mRNA-1273/administración & dosificación , Vacuna nCoV-2019 mRNA-1273/inmunología , Masculino , Femenino , Persona de Mediana Edad , COVID-19/prevención & control , COVID-19/inmunología , Adulto , Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , Anciano , SARS-CoV-2/inmunología , Vacunas contra la COVID-19/efectos adversos , Vacunas contra la COVID-19/inmunología , Vacunas contra la COVID-19/administración & dosificación , Trasplante de Órganos/efectos adversos , Inmunogenicidad Vacunal , Trasplante de Hígado/efectos adversos , Trasplante de Riñón/efectos adversos , Vacunación/efectos adversos , Huésped Inmunocomprometido
2.
J Infect Dis ; 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38889247

RESUMEN

BACKGROUND: The mRNA-1345 vaccine demonstrated efficacy against RSV disease with acceptable safety in adults ≥60 years in the ConquerRSV trial. Here, humoral immunogenicity results from the trial are presented. METHODS: This phase 2/3 trial randomly assigned adults (≥60 years) to mRNA-1345 50-µg encoding prefusion F (preF) glycoprotein (n = 17,793) vaccine or placebo (n = 17,748). RSV-A and RSV-B neutralizing antibody (nAb) and preF binding antibody (bAb) levels at baseline and day 29 post-vaccination were assessed in a per-protocol immunogenicity subset ([PPIS]; mRNA-1345, n = 1515; placebo, n = 333). RESULTS: Day 29 nAb geometric mean titers (GMTs) increased 8.4-fold against RSV-A and 5.1-fold against RSV-B from baseline. Seroresponses (4-fold rise from baseline) in the mRNA-1345 groups were 74.2% and 56.5% for RSV-A and RSV-B, respectively. Baseline GMTs were lower among participants who met the seroresponse criteria than those who did not. mRNA-1345 induced preF bAbs at day 29, with a pattern similar to nAbs. Day 29 antibody responses across demographic and risk subgroups were generally consistent with the overall PPIS. CONCLUSION: mRNA-1345 enhanced RSV-A and RSV-B nAbs and preF bAbs in adults (≥60 years) across various subgroups, including those at risk for severe disease, consistent with its demonstrated efficacy in the prevention of RSV disease.

3.
J Infect Dis ; 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39225478

RESUMEN

Coronavirus disease 2019 (COVID-19) vaccines reduce severe disease and mortality and may lessen transmission, measured by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral load (VL). Evaluating vaccine associations in VL at COVID-19 diagnosis in 4 phase 3 randomized, placebo-controlled vaccine trials, July 2020 to July 2021, VL reductions were 2.78 log10 copies/mL (95% confidence interval [CI], 1.38-4.18; n = 60 placebo, 11 vaccine) and 2.12 log10 copies/mL (95% CI, 1.44-2.80; n = 594 placebo, 36 vaccine) for NVX-CoV2373 and mRNA-1273, respectively. Associations were not significant for AZD1222 (0.59 log10 copies/mL; 95% CI, -.19 to 1.36; n = 90 placebo, 78 vaccine) or Ad26.COV2.S (0.23 log10 copies/mL; 95% CI, -.01 to .47; n = 916 placebo, 424 vaccine). Thus, vaccines potentially decreased transmission when ancestral SARS-CoV-2 predominated. Clinical Trials Registration. NCT04470427, NCT04505722, NCT04516746, NCT04611802.

4.
J Infect Dis ; 227(2): 268-277, 2023 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-35776140

RESUMEN

BACKGROUND: From 2019 to 2021, Rwandan residents of the border with the Democratic Republic of the Congo were offered the Ad26.ZEBOV (adenovirus type 26 vector vaccine encoding Ebola virus glycoprotein) and MVA-BN-Filo (modified vaccinia virus Ankara vector vaccine, encoding glycoproteins from Ebola, Sudan, Marburg, and nucleoprotein from Tai Forest viruses) Ebola vaccine regimen. METHODS: Nonpregnant persons aged ≥2 years were eligible. Unsolicited adverse events (UAEs) were reported through phone calls or visits, and serious adverse events (SAEs) were recorded per International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use guidelines. RESULTS: Following Ad26.ZEBOV, UAEs were reported by 0.68% of 216 113 vaccinees and were more common in younger children (aged 2-8 years, 1.2%) compared with older children (aged 9-17 years, 0.4%) and adults (aged ≥18 years, 0.7%). Fever and headache were the most reported symptoms. All 17 SAEs related to vaccine were in children aged 2-8 years (10 postvaccination febrile convulsions ± gastroenteritis and 7 fever and/or gastroenteritis). The incidence of febrile seizures was 8 of 26 062 (0.031%) prior to initiation of routine acetaminophen in December 2020 and 2 of 15 897 (0.013%) thereafter. Nonobstetric SAEs were similar in males and females. All 20 deaths were unrelated to vaccination. Young girls and adult women with UAEs were less likely to receive the second dose than those without UAEs. Seven unrelated SAEs occurred in 203 267 MVA-BN-Filo recipients. CONCLUSIONS: Postvaccination febrile convulsions in young children were rare but not previously described after Ad26.ZEBOV and were reduced with routine acetaminophen. The regimen was otherwise safe and well-tolerated.


Asunto(s)
Vacunas contra el Virus del Ébola , Ebolavirus , Fiebre Hemorrágica Ebola , Convulsiones Febriles , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Masculino , Acetaminofén , Anticuerpos Antivirales , Vacunas contra el Virus del Ébola/efectos adversos , Glicoproteínas , Fiebre Hemorrágica Ebola/prevención & control , Convulsiones Febriles/inducido químicamente , Vacunación/efectos adversos , Virus Vaccinia
5.
Lancet ; 392(10143): 232-243, 2018 07 21.
Artículo en Inglés | MEDLINE | ID: mdl-30047376

RESUMEN

BACKGROUND: More than 1·8 million new cases of HIV-1 infection were diagnosed worldwide in 2016. No licensed prophylactic HIV-1 vaccine exists. A major limitation to date has been the lack of direct comparability between clinical trials and preclinical studies. We aimed to evaluate mosaic adenovirus serotype 26 (Ad26)-based HIV-1 vaccine candidates in parallel studies in humans and rhesus monkeys to define the optimal vaccine regimen to advance into clinical efficacy trials. METHODS: We conducted a multicentre, randomised, double-blind, placebo-controlled phase 1/2a trial (APPROACH). Participants were recruited from 12 clinics in east Africa, South Africa, Thailand, and the USA. We included healthy, HIV-1-uninfected participants (aged 18-50 years) who were considered at low risk for HIV-1 infection. We randomly assigned participants to one of eight study groups, stratified by region. Participants and investigators were blinded to the treatment allocation throughout the study. We primed participants at weeks 0 and 12 with Ad26.Mos.HIV (5 × 1010 viral particles per 0·5 mL) expressing mosaic HIV-1 envelope (Env)/Gag/Pol antigens and gave boosters at weeks 24 and 48 with Ad26.Mos.HIV or modified vaccinia Ankara (MVA; 108 plaque-forming units per 0·5 mL) vectors with or without high-dose (250 µg) or low-dose (50 µg) aluminium adjuvanted clade C Env gp140 protein. Those in the control group received 0·9% saline. All study interventions were administered intramuscularly. Primary endpoints were safety and tolerability of the vaccine regimens and Env-specific binding antibody responses at week 28. Safety and immunogenicity were also assessed at week 52. All participants who received at least one vaccine dose or placebo were included in the safety analysis; immunogenicity was analysed using the per-protocol population. We also did a parallel study in rhesus monkeys (NHP 13-19) to assess the immunogenicity and protective efficacy of these vaccine regimens against a series of six repetitive, heterologous, intrarectal challenges with a rhesus peripheral blood mononuclear cell-derived challenge stock of simian-human immunodeficiency virus (SHIV-SF162P3). The APPROACH trial is registered with ClinicalTrials.gov, number NCT02315703. FINDINGS: Between Feb 24, 2015, and Oct 16, 2015, we randomly assigned 393 participants to receive at least one dose of study vaccine or placebo in the APPROACH trial. All vaccine regimens demonstrated favourable safety and tolerability. The most commonly reported solicited local adverse event was mild-to-moderate pain at the injection site (varying from 69% to 88% between the different active groups vs 49% in the placebo group). Five (1%) of 393 participants reported at least one grade 3 adverse event considered related to the vaccines: abdominal pain and diarrhoea (in the same participant), increased aspartate aminotransferase, postural dizziness, back pain, and malaise. The mosaic Ad26/Ad26 plus high-dose gp140 boost vaccine was the most immunogenic in humans; it elicited Env-specific binding antibody responses (100%) and antibody-dependent cellular phagocytosis responses (80%) at week 52, and T-cell responses at week 50 (83%). We also randomly assigned 72 rhesus monkeys to receive one of five different vaccine regimens or placebo in the NHP 13-19 study. Ad26/Ad26 plus gp140 boost induced similar magnitude, durability, and phenotype of immune responses in rhesus monkeys as compared with humans and afforded 67% protection against acquisition of SHIV-SF162P3 infection (two-sided Fisher's exact test p=0·007). Env-specific ELISA and enzyme-linked immunospot assay responses were the principal immune correlates of protection against SHIV challenge in monkeys. INTERPRETATION: The mosaic Ad26/Ad26 plus gp140 HIV-1 vaccine induced comparable and robust immune responses in humans and rhesus monkeys, and it provided significant protection against repetitive heterologous SHIV challenges in rhesus monkeys. This vaccine concept is currently being evaluated in a phase 2b clinical efficacy study in sub-Saharan Africa (NCT03060629). FUNDING: Janssen Vaccines & Prevention BV, National Institutes of Health, Ragon Institute of MGH, MIT and Harvard, Henry M Jackson Foundation for the Advancement of Military Medicine, US Department of Defense, and International AIDS Vaccine Initiative.


Asunto(s)
Vacunas contra el SIDA/administración & dosificación , VIH-1/inmunología , Vacunas contra el SIDA/efectos adversos , Dolor Abdominal/etiología , Adenoviridae , Adolescente , Adulto , Animales , Aspartato Aminotransferasas/análisis , Dolor de Espalda/etiología , Diarrea/etiología , Mareo/etiología , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Fatiga/etiología , Vectores Genéticos , Voluntarios Sanos , Humanos , Inmunidad Celular , Inmunidad Humoral , Macaca mulatta , Persona de Mediana Edad , Adulto Joven
6.
AIDS Behav ; 22(4): 1165-1173, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29090394

RESUMEN

Measuring PrEP adherence remains challenging. In 2009-2010, the International AIDS Vaccine Initiative randomized phase II trial participants to daily tenofovir disoproxil fumarate/emtricitabine or placebo in Uganda and Kenya. Adherence was measured by electronic monitoring (EM), self-report (SR), and drug concentrations in plasma and hair. Each adherence measure was categorised as low, moderate, or high and also considered continuously; the incremental value of combining measures was determined. Forty-five participants were followed over 4 months. Discrimination for EM adherence by area under receiver operating curves (AROC) was poor for SR (0.53) and best for hair (AROC 0.85). When combining hair with plasma or hair with self-report, discrimination was improved (AROC > 0.9). Self-reported adherence was of low utility by itself. Hair level was the single best PK measure to predict EM-assessed adherence; the other measurements had lower discrimination values. Combining short-term (plasma) and long-term (hair) metrics could be useful to assess patterns of drug-taking in the context of PrEP.


Asunto(s)
Fármacos Anti-VIH/administración & dosificación , Emtricitabina/administración & dosificación , Infecciones por VIH/prevención & control , Cabello/metabolismo , Cumplimiento de la Medicación , Profilaxis Pre-Exposición/métodos , Autoinforme , Tenofovir/administración & dosificación , Administración Oral , Adulto , Fármacos Anti-VIH/sangre , Emtricitabina/sangre , Femenino , Infecciones por VIH/psicología , Cabello/química , Humanos , Kenia , Masculino , Tenofovir/sangre , Uganda
7.
J Med Internet Res ; 19(7): e274, 2017 07 31.
Artículo en Inglés | MEDLINE | ID: mdl-28760729

RESUMEN

BACKGROUND: Digital technologies, especially if used in novel ways, provide a number of potential advantages to clinical research in trials related to human immunodeficiency virus (HIV) and acquired immune deficiency syndrome (AIDS) and may greatly facilitate operations as well as data collection and analysis. These technologies may even allow answering questions that are not answerable with older technologies. However, they come with a variety of potential concerns for both the participants and the trial sponsors. The exact challenges and means for alleviation depend on the technology and on the population in which it is deployed, and the rapidly changing landscape of digital technologies presents a challenge for creating future-proof guidelines for technology application. OBJECTIVE: The aim of this study was to identify and summarize some common themes that are frequently encountered by researchers in this context and highlight those that should be carefully considered before making a decision to include these technologies in their research. METHODS: In April 2016, the Global HIV Vaccine Enterprise surveyed the field for research groups with recent experience in novel applications of digital technologies in HIV clinical research and convened these groups for a 1-day meeting. Real-world uses of various technologies were presented and discussed by 46 attendees, most of whom were researchers involved in the design and conduct of clinical trials of biomedical HIV prevention and treatment approaches. After the meeting, a small group of organizers reviewed the presentations and feedback obtained during the meeting and categorized various lessons-learned to identify common themes. A group of 9 experts developed a draft summary of the findings that was circulated via email to all 46 attendees for review. Taking into account the feedback received, the group finalized the considerations that are presented here. RESULTS: Meeting presenters and attendees discussed the many successful applications of digital technologies to improve research outcomes, such as those for recruitment and enrollment, participant identification, informed consent, data collection, data quality, and protocol or treatment adherence. These discussions also revealed unintended consequence of technology usage, including risks to study participants and risks to study integrity. CONCLUSIONS: Key lessons learned from these discussions included the need to thoroughly evaluate systems to be used, the idea that early success may not be sustained throughout the study, that some failures will occur, and considerations for study-provided devices. Additionally, taking these key lessons into account, the group generated recommendations on how to move forward with the use of technology in HIV vaccine and biomedical prevention trials.


Asunto(s)
Infecciones por VIH/terapia , Tecnología/métodos , Humanos , Proyectos de Investigación
8.
AIDS Behav ; 19(5): 794-801, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25432877

RESUMEN

A qualitative assessment of Kenyan men who have sex with men taking daily and intermittent oral HIV pre-exposure prophylaxis (PrEP) found stigma, sex work, mobility, and alcohol impacted adherence. We analyzed quantitative data from the same cohort to explore different definitions of intermittent adherence. Volunteers were randomized to daily emtricitabine/tenofovir or placebo, or intermittent (prescription: Mondays/Fridays/after sex, maximum 1 dose/day) emtricitabine/tenofovir or placebo (2:1:2:1), and followed for 4 months. By electronic monitoring, median adherence for daily dosing was 80 %. Median adherence for intermittent dosing was 71 % per a "relaxed" definition (accounting for off-prescription dosing) and 40 % per a "strict" definition (limited to the prescription). Factors associated with lower adherence included travel, transactional sex, and longer follow-up; higher adherence was associated with daily dosing and an income. The definition of intermittent dosing strongly affects interpretation of adherence. These findings suggest interventions should address challenges of mobility, sex work, and long-term PrEP.


Asunto(s)
Fármacos Anti-VIH/administración & dosificación , Emtricitabina/administración & dosificación , Infecciones por VIH/prevención & control , Homosexualidad Masculina , Cumplimiento de la Medicación/estadística & datos numéricos , Profilaxis Pre-Exposición/métodos , Tenofovir/administración & dosificación , Administración Oral , Fármacos Anti-VIH/uso terapéutico , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Emtricitabina/uso terapéutico , Femenino , Infecciones por VIH/tratamiento farmacológico , Humanos , Kenia , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Factores Socioeconómicos , Tenofovir/uso terapéutico
9.
Lancet Infect Dis ; 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39332418

RESUMEN

BACKGROUND: Most individuals show immunity to SARS-CoV-2 from vaccination or infection, or both. We aimed to determine the safety and immunogenicity of an omicron-containing COVID-19 vaccine (mRNA-1273.222) in vaccine-naive adolescents who were SARS-CoV-2 positive. METHODS: Part 3 of the phase 2/3 TeenCOVE trial was a phase 3, open-label, single-arm part done in the USA and the Dominican Republic that enrolled healthy, vaccine-naive adolescents (aged 12-17 years) to receive two 50 µg doses of mRNA-1273.222 (ancestral strain Wuhan-Hu-1 and omicron subvariants BA.4 and BA.5), 6 months apart. Primary reactogenicity and safety outcomes included assessment of solicited local or systemic adverse reactions 7 days after vaccination, and unsolicited and prespecified adverse events throughout study participation. Inferred effectiveness (primary immunogenicity outcome) was established by comparing neutralising antibody responses 28 days after dose 1 of mRNA-1273.222 in SARS-CoV-2-positive adolescents with responses 28 days after dose 2 of mRNA-1273 100 µg primary series in SARS-CoV-2-negative young adults (aged 18-25 years) from the COVE trial. This study is registered with ClinicalTrials.gov (NCT04649151). FINDINGS: Between Dec 21, 2022, and June 5, 2023, 379 adolescents (378 of whom were SARS-CoV-2 positive) received at least one mRNA-1273.222 dose and were included in the safety analysis set. The reactogenicity profile was favourable compared with the mRNA-1273 primary series, with no new safety concerns identified. Unsolicited adverse events were reported in 49 (13%) of 379 participants; no deaths or adverse events leading to study discontinuation were reported. The immunogenicity set included 245 adolescents from the per-protocol immunogenicity subset who were SARS-CoV-2 positive at baseline and 296 young adults who were SARS-CoV-2 negative. Compared with the mRNA-1273 primary series in SARS-CoV-2-negative young adults, a single dose of mRNA-1273.222 induced superior (geometric mean ratio [GMR] 95% CI lower bound >1) neutralising antibody responses against omicron BA.4 and BA.5 (GMR 48·95 [95% CI 44·21-54·21]) and non-inferior (GMR 95% CI lower bound >0·667) neutralising antibody responses against ancestral SARS-CoV-2 (GMR 4·25 [95% CI 3·69-4·88]) in SARS-CoV-2-positive adolescents. INTERPRETATION: In vaccine-naive, SARS-CoV-2-positive adolescents, single-dose mRNA-1273.222 was effective against COVID-19 based on successful immunobridging to the two-dose mRNA-1273 primary series in young adults. The findings support a simplified single-dose vaccination schedule with variant-containing mRNA vaccines, regardless of previous vaccination status. FUNDING: Moderna.

10.
EClinicalMedicine ; 74: 102720, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39091673

RESUMEN

Background: Longitudinal changes in vaccination-induced immune response remain inadequately characterized in adolescents. We present long-term safety, immunogenicity, and COVID-19 incidence following a 2-dose mRNA-1273 100-µg primary series, and immunogenicity following a single dose of mRNA-1273 50 µg in vaccine-naïve adolescents. Methods: TeenCOVE (NCT04649151) Part 1 randomized adolescents (12-17 years) to 2-dose mRNA-1273 100 µg (n = 2490) or placebo (n = 1243) 28 days apart. Subsequently, placebo recipients (n = 91) could receive open-label mRNA-1273. Primary objectives included prespecified adverse events through 12 months; secondary objectives were COVID-19 incidence and neutralizing and spike-binding antibodies (nAbs/bAbs) against SARS-CoV-2 (ancestral/variants) through 12 months (study period: December 2020-January 2022). In Part 2, vaccine-naïve adolescents (n = 52) received up to 2 doses of mRNA-1273 50 µg; interim analysis included Day 28 (D28) nAbs post-injection 1 in SARS-CoV-2-baseline-positive participants (serologic/virologic evidence of prior infection). Findings: In SARS-CoV-2-baseline-negative adolescents (N = 369), mRNA-1273 induced robust nAb responses versus baseline (geometric mean concentration [GMC] = 11; 95% CI, 11-12) at D28 (1868 [1759-1985]), 6 months (625 [583-670]) and 12 months (550 [490-618]) post-injection 2. Similar bAb responses were observed to alpha/beta/delta/gamma variants; nAb/bAb responses were similar in SARS-CoV-2-baseline-positive adolescents. The 2-dose mRNA-1273 100-µg primary series was generally well-tolerated; one case of nonserious, moderate, probable acute myocarditis resolved by 8 days from symptom onset. A single dose of mRNA-1273 50 µg in SARS-CoV-2-baseline-positive adolescents induced higher D28 nAb GMCs against ancestral SARS-CoV-2 than 2-dose mRNA-1273 100 µg in young adults (geometric mean ratio = 4.322 [3.274-5.707]). Interpretation: The overall risk-benefit profile of mRNA-1273 remains favorable in adolescents, with durable 12-month immune responses against SARS-CoV-2 (ancestral/variants). A single mRNA-1273 50-µg injection in vaccine-naïve adolescents elicited robust immune responses against SARS-CoV-2. Funding: This project has been funded in whole or in part with federal funds by the Department of Health and Human Services, United States; Administration for Strategic Preparedness and Response, United States; Biomedical Advanced Research and Development Authority, United States, under Contract No. 75A50120C00034. The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the Department of Health and Human Services or its components.

11.
Expert Rev Vaccines ; 23(1): 862-878, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39234779

RESUMEN

INTRODUCTION: Vaccination against SARS-CoV-2 is an integral pillar of the public health approach to COVID-19. With the emergence of variants of concern that increase transmissibility and escape from vaccine- or infection-induced protection, vaccines have been developed to more closely match the newly circulating SARS-CoV-2 strains to improve protection. The safety and immunogenicity of multiple authorized messenger RNA (mRNA)-based COVID-19 vaccines targeting the omicron sublineage (BA.1, BA.4/BA.5, and XBB.1.5) have been demonstrated in several clinical trials among adults and children. AREAS COVERED: This review will comprehensively detail the available evidence (published through July 2024) from ongoing clinical trials on omicron variant-containing mRNA-1273 vaccines administered as additional doses in previously vaccinated target demographics. EXPERT OPINION: Across three clinical trials, omicron variant-containing mRNA-1273 vaccines induced immune responses to vaccine-matched omicron strains as well as ancestral SARS-CoV-2, with a safety and reactogenicity profile comparable to the original mRNA-1273 vaccine. Combined with pivotal data demonstrating the safety, efficacy, and effectiveness of the original mRNA-1273 vaccine, these findings support the use of variant-containing mRNA-1273 vaccines and provide confidence that expeditious development of updated vaccines using this established mRNA platform can maintain protection against COVID-19.


Asunto(s)
Vacuna nCoV-2019 mRNA-1273 , Vacunas contra la COVID-19 , COVID-19 , Inmunización Secundaria , Inmunogenicidad Vacunal , SARS-CoV-2 , Humanos , COVID-19/prevención & control , COVID-19/inmunología , Vacunas contra la COVID-19/inmunología , Vacunas contra la COVID-19/administración & dosificación , Vacunas contra la COVID-19/efectos adversos , Vacuna nCoV-2019 mRNA-1273/inmunología , SARS-CoV-2/inmunología , SARS-CoV-2/genética , Inmunización Secundaria/métodos , Adulto , Niño
12.
Lancet Infect Dis ; 24(7): 687-697, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38518789

RESUMEN

BACKGROUND: Variant-containing mRNA vaccines for COVID-19 to broaden protection against SARS-CoV-2 variants are recommended based on findings in adults. We report interim safety and immunogenicity of an omicron BA.1 variant-containing (mRNA-1273.214) primary vaccination series and booster dose in paediatric populations. METHODS: This open-label, two-part, non-randomised phase 3 trial enrolled participants aged 6 months to 5 years at 24 US study sites. Eligible participants were generally healthy or had stable chronic conditions, without known SARS-CoV-2 infection in the previous 90 days. Individuals who were acutely ill or febrile 1 day before or at the screening visit or those who previously received other COVID-19 vaccines (except mRNA-1273 for part 2) were excluded. In part 1, SARS-CoV-2-vaccine-naive participants received two-dose mRNA-1273.214 (25 µg; omicron BA.1 and ancestral Wuhan-Hu-1 mRNA) primary series. In part 2, participants who previously completed the two-dose mRNA-1273 (25 µg) primary series in KidCOVE (NCT04796896) received a mRNA-1273.214 (10 µg) booster dose. Primary study outcomes were safety and reactogenicity of the mRNA-1273.214 primary series (part 1) or booster dose (part 2) as well as the inferred effectiveness of mRNA-1273.214 based on immune responses against ancestral SARS-CoV-2 (D614G) and omicron BA.1 variant at 28 days post-primary series (part 1) or post-booster dose (part 2). The safety set included participants who received at least one dose of the study vaccine; the immunogenicity set included those who provided immunogenicity samples. Interim safety and immunogenicity are summarised in this analysis as of the data cutoff date (Dec 5, 2022). This trial is registered with ClinicalTrials.gov, NCT05436834. FINDINGS: Between June 21, 2022, and Dec 5, 2022, 179 participants received one or more doses of mRNA-1273.214 primary series (part 1) and 539 received a mRNA-1273.214 booster dose (part 2). The safety profile within 28 days after either dose of the mRNA-1273.214 primary series and the booster dose was consistent with that of the mRNA-1273 primary series in this age group, with no new safety concerns or vaccine-related serious adverse events observed. At 28 days after primary series dose 2 and the booster dose, both mRNA-1273.214 primary series (day 57, including all participants with or without evidence of prior SARS-CoV-2 infection at baseline) and booster (day 29, including participants without evidence of prior SARS-CoV-2 infection at baseline) elicited responses that were superior against omicron-BA.1 (geometric mean ratio part 1: 25·4 [95% CI 20·1-32·1] and part 2: 12·5 [11·0-14·3]) and non-inferior against D614G (part 1: 0·8 [0·7-1·0] and part 2: 3·1 [2·8-3·5]), compared with neutralising antibody responses induced by the mRNA-1273 primary series (in a historical comparator group). INTERPRETATION: mRNA-1273.214 was immunogenic against BA.1 and D614G in children aged 6 months to 5 years, with a comparable safety profile to mRNA-1273, when given as a two-dose primary series or a booster dose. These results are aligned with the US Centers for Disease Control and Prevention recommendations for the use of variant-containing vaccines for continued protection against the emerging variants of SARS-CoV-2. FUNDING: Moderna.


Asunto(s)
Vacuna nCoV-2019 mRNA-1273 , Anticuerpos Antivirales , Vacunas contra la COVID-19 , COVID-19 , Inmunización Secundaria , Inmunogenicidad Vacunal , SARS-CoV-2 , Humanos , COVID-19/prevención & control , COVID-19/inmunología , Masculino , Femenino , SARS-CoV-2/inmunología , SARS-CoV-2/genética , Preescolar , Lactante , Vacunas contra la COVID-19/inmunología , Vacunas contra la COVID-19/efectos adversos , Vacunas contra la COVID-19/administración & dosificación , Vacuna nCoV-2019 mRNA-1273/inmunología , Anticuerpos Antivirales/sangre , Estados Unidos , Anticuerpos Neutralizantes/sangre , Vacunación/métodos
13.
Nat Commun ; 15(1): 7469, 2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39209823

RESUMEN

Primary vaccination with mRNA-1273 (100-µg) was safe and efficacious at preventing coronavirus disease 2019 (COVID-19) in the previously reported, blinded Part A of the phase 3 Coronavirus Efficacy (COVE; NCT04470427) trial in adults (≥18 years) across 99 U.S. sites. The open-label (Parts B and C) primary objectives were evaluation of long-term safety and effectiveness of primary vaccination plus a 50-µg booster dose; immunogenicity was a secondary objective. Of 29,035 open-label participants, 19,609 received boosters (mRNA-1273 [n = 9647]; placebo-mRNA-1273 [n = 9952]; placebo [n = 10] groups). Booster safety was consistent with that reported for primary vaccination. Incidences of COVID-19 and severe COVID-19 were higher during the Omicron BA.1 than Delta variant waves and boosting versus non-boosting was associated with a significant, 47.0% (95% CI : 39.0-53.9%) reduction of Omicron BA.1 incidence (24.6 [23.4 - 25.8] vs 46.4 [40.6 - 52.7]/1000 person-months). In an exploratory Cox regression model adjusted for time-varying covariates, a longer median interval between primary vaccination and boosting (mRNA-1273 [13 months] vs placebo-mRNA-1273 [8 months]) was associated with significantly lower, COVID-19 risk (24.0% [16.0% - 32.0%]) during Omicron BA.1 predominance. Boosting elicited greater immune responses against SARS-CoV-2 than primary vaccination, irrespective of prior SARS-CoV-2 infection. Primary vaccination and boosting with mRNA-1273 demonstrated acceptable safety, effectiveness and immunogenicity against COVID-19, including emergent variants.


Asunto(s)
Vacuna nCoV-2019 mRNA-1273 , Vacunas contra la COVID-19 , COVID-19 , Inmunización Secundaria , SARS-CoV-2 , Humanos , Vacuna nCoV-2019 mRNA-1273/inmunología , COVID-19/prevención & control , COVID-19/inmunología , Adulto , Masculino , Femenino , SARS-CoV-2/inmunología , Persona de Mediana Edad , Vacunas contra la COVID-19/inmunología , Vacunas contra la COVID-19/efectos adversos , Vacunas contra la COVID-19/administración & dosificación , Eficacia de las Vacunas , Anticuerpos Antivirales/inmunología , Anticuerpos Antivirales/sangre , Inmunogenicidad Vacunal , Anciano , Adulto Joven , Vacunación , Adolescente
14.
Nat Commun ; 15(1): 7954, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39261482

RESUMEN

In the phase 3 Coronavirus Efficacy (COVE) trial (NCT04470427), post-dose two Ancestral Spike-specific binding (bAb) and neutralizing (nAb) antibodies were shown to be correlates of risk (CoR) and of protection against Ancestral-lineage COVID-19 in SARS-CoV-2 naive participants. In the SARS-CoV-2 Omicron era, Omicron subvariants with varying degrees of immune escape now dominate, seropositivity rates are high, and booster doses are administered, raising questions on whether and how these developments affect the bAb and nAb correlates. To address these questions, we assess post-boost BA.1 Spike-specific bAbs and nAbs as CoRs and as correlates of booster efficacy in COVE. For naive individuals, bAbs and nAbs inversely correlate with Omicron COVID-19: hazard ratios (HR) per 10-fold marker increase (95% confidence interval) are 0.16 (0.03, 0.79) and 0.31 (0.10, 0.96), respectively. In non-naive individuals the analogous results are similar: 0.15 (0.04, 0.63) and 0.28 (0.07, 1.08). For naive individuals, three vs two-dose booster efficacy correlates with predicted nAb titer at exposure, with estimates -8% (-126%, 48%), 50% (25%, 67%), and 74% (49%, 87%), at 56, 251, and 891 Arbitrary Units/ml. These results support the continued use of antibody as a surrogate endpoint.


Asunto(s)
Vacuna nCoV-2019 mRNA-1273 , Anticuerpos Neutralizantes , Anticuerpos Antivirales , COVID-19 , Inmunización Secundaria , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus , Humanos , COVID-19/inmunología , COVID-19/virología , COVID-19/prevención & control , SARS-CoV-2/inmunología , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Anticuerpos Antivirales/sangre , Glicoproteína de la Espiga del Coronavirus/inmunología , Vacuna nCoV-2019 mRNA-1273/administración & dosificación , Vacuna nCoV-2019 mRNA-1273/inmunología , Vacunas contra la COVID-19/inmunología , Vacunas contra la COVID-19/administración & dosificación , Femenino , Masculino , Adulto , Eficacia de las Vacunas
15.
AIDS Behav ; 17(6): 2162-72, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23080358

RESUMEN

This paper used qualitative methods to explore experiences of men who have sex with men and female sex workers in Nairobi and Mtwapa, Kenya, who used oral pre-exposure prophylaxis (PrEP) for HIV prevention as part of a four-month trial of safety, acceptability and adherence. Fifty-one of 72 volunteers who took part in a randomized, placebo-controlled, blinded trial that compared daily and intermittent dosage of PrEP underwent qualitative assessments after completing the trial. Analyses identified three themes: (i) acceptability of PrEP was high, i.e. side effects were experienced early in the study but diminished over time, however characteristics of pills could improve comfort and use; (ii) social impacts such as stigma, rumors, and relationship difficulties due to being perceived as HIV positive were prevalent; (iii) adherence was challenged by complexities of daily life, in particular post-coital dosing adherence suffered from alcohol use around time of sex, mobile populations, and transactional sex work. These themes resonated across dosing regimens and gender, and while most participants favored the intermittent dosing schedule, those in the intermittent group noted particular challenges in adhering to the post-coital dose. Culturally appropriate and consistent counseling addressing these issues may be critical for PrEP effectiveness.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/prevención & control , Cumplimiento de la Medicación/estadística & datos numéricos , Adolescente , Adulto , Fármacos Anti-VIH/administración & dosificación , Desoxicitidina/administración & dosificación , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapéutico , Combinación de Medicamentos , Combinación Emtricitabina y Fumarato de Tenofovir Disoproxil , Femenino , Homosexualidad Masculina/psicología , Humanos , Kenia , Masculino , Cumplimiento de la Medicación/psicología , Persona de Mediana Edad , Compuestos Organofosforados/administración & dosificación , Compuestos Organofosforados/uso terapéutico , Trabajadores Sexuales/psicología , Estereotipo , Adulto Joven
16.
Vaccine ; 41(38): 5535-5544, 2023 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-37516574

RESUMEN

The ability of a third dose of the Pfizer-BioNTech BNT162b2 SARS-CoV-2 vaccine to stimulate immune responses against subvariants, including Omicron BA.1, has not been assessed in New Zealand populations. Unlike many overseas populations, New Zealanders were largely infection naïve at the time they were boosted. This adult cohort of 298 participants, oversampled for at-risk populations, was composed of 29% Maori and 28% Pacific peoples, with 40% of the population aged 55+. A significant proportion of the cohort was obese and presented with at least one comorbidity. Sera were collected 28 days and 6 months post second vaccination and 28 days post third vaccination. SARS-CoV-2 anti-S IgG titres and neutralising capacity using surrogate viral neutralisation assays against variants of concern, including Omicron BA.1, were investigated. The incidence of SARS-CoV-2 infection, within our cohort, prior to third vaccination was very low (<6%). This study found a third vaccine significantly increased the mean SARS-CoV-2 anti-S IgG titres, for every demographic subgroup, by a minimum of 1.5-fold compared to titres after two doses. Diabetic participants experienced a greater increase (∼4-fold) in antibody titres after their third vaccination, compared to non-diabetics (increase of âˆ¼ 2-fold). This corrected for the deficiency in antibody titres within diabetic participants which was observed following two doses. A third dose also induced a neutralising response against Omicron variant BA.1, which was absent after two doses. This neutralising response improved regardless of age, BMI, ethnicity, or diabetes status. Participants aged ≥75 years consistently had the lowest SARS-CoV-2 anti-S IgG titres at each timepoint, however experienced the greatest improvement after three doses compared to younger participants. This study shows that in the absence of prior SARS-CoV-2 infection, a third Pfizer-BioNTech BNT162b2 vaccine enhances immunogenicity, including against Omicron BA.1, in a cohort representative of at-risk groups in the adult New Zealand population.


Asunto(s)
Vacuna BNT162 , COVID-19 , Adulto , Humanos , Anticuerpos Neutralizantes , Anticuerpos Antivirales , COVID-19/epidemiología , COVID-19/prevención & control , Vacunas contra la COVID-19 , Inmunoglobulina G , Pueblo Maorí , Nueva Zelanda/epidemiología , SARS-CoV-2 , Vacunación , Persona de Mediana Edad , Pueblos Isleños del Pacífico , Inmunogenicidad Vacunal
17.
PLoS Pathog ; 6(8): e1001028, 2010 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-20700449

RESUMEN

A protective vaccine against HIV-1 will likely require the elicitation of a broadly neutralizing antibody (bNAb) response. Although the development of an immunogen that elicits such antibodies remains elusive, a proportion of HIV-1 infected individuals evolve broadly neutralizing serum responses over time, demonstrating that the human immune system can recognize and generate NAbs to conserved epitopes on the virus. Understanding the specificities that mediate broad neutralization will provide insight into which epitopes should be targeted for immunogen design and aid in the isolation of broadly neutralizing monoclonal antibodies from these donors. Here, we have used a number of new and established technologies to map the bNAb specificities in the sera of 19 donors who exhibit among the most potent cross-clade serum neutralizing activities observed to date. The results suggest that broad and potent serum neutralization arises in most donors through a limited number of specificities (1-2 per donor). The major targets recognized are an epitope defined by the bNAbs PG9 and PG16 that is associated with conserved regions of the V1, V2 and V3 loops, an epitope overlapping the CD4 binding site and possibly the coreceptor binding site, an epitope sensitive to a loss of the glycan at N332 and distinct from that recognized by the bNAb 2G12 and an epitope sensitive to an I165A substitution. In approximately half of the donors, key N-linked glycans were critical for expression of the epitopes recognized by the bNAb specificities in the sera.


Asunto(s)
Vacunas contra el SIDA/inmunología , Anticuerpos Neutralizantes/inmunología , Especificidad de Anticuerpos/inmunología , Anticuerpos Anti-VIH/inmunología , VIH-1/inmunología , Adulto , Anticuerpos Neutralizantes/biosíntesis , Reacciones Cruzadas , Epítopos de Linfocito B/inmunología , Femenino , Anticuerpos Anti-VIH/biosíntesis , Proteína gp120 de Envoltorio del VIH/inmunología , Proteína gp41 de Envoltorio del VIH/inmunología , Humanos , Masculino , Productos del Gen env del Virus de la Inmunodeficiencia Humana/inmunología
18.
AIDS Care ; 24(10): 1277-89, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22452384

RESUMEN

Standards of care provided to volunteers in HIV prevention research in developing countries are evolving. Inconsistency in standards, particularly within a research network highlights the need to balance volunteers' health and wellness with the efficient conduct of research. Ten research centers (RC's) in East and Southern Africa affiliated with the International AIDS Vaccine Initiative (IAVI) were studied using a mixed methods approach to understand variations, similarities and gaps in services provided, recipients of services, referral systems, and barriers to referral uptake. These data were then used to develop expected standards across the 10 RCs. Findings indicated that RCs consistently provided HIV risk reduction and family planning (FP) counseling, male condoms, management of sexually transmitted infections, CD-4 counts, and general medical care to volunteers and non-research volunteers. Services that were less consistently provided on-site included: female condoms, adult male circumcision (AMC), antiretroviral therapy (ART) and post-exposure prophylaxis (PEP) in case of rape. The FP options provided on-site varied, with few providing implants, intrauterine devices, tubal ligation, and vasectomy. Most RCs had established referral systems for ART, AMC, PEP, and FP, but few had referral points for psychosocial services. Few RCs had comprehensive guidelines on referrals other than those related to adverse events. Findings indicate that the greatest challenges for referral uptake were transportation and health care costs, poor quality and inconsistency of services at some referral points. Few RCs covered the cost of referrals for non-study related adverse events. A collaborative process between IAVI and the RCs was undertaken to reach consensus on expected standards of care. A set of required and recommended services to be provided on-site or by referral was developed. In developing such standards, we tried to balance scientific priorities, equity, contextual realities, community expectations, and cost-effectiveness.


Asunto(s)
Consejo/normas , Servicios de Planificación Familiar/normas , Infecciones por VIH/epidemiología , Investigación sobre Servicios de Salud/organización & administración , Aceptación de la Atención de Salud/estadística & datos numéricos , Nivel de Atención/estadística & datos numéricos , África Oriental/epidemiología , África Austral/epidemiología , Recuento de Linfocito CD4 , Estudios de Casos y Controles , Atención a la Salud , Femenino , Infecciones por VIH/tratamiento farmacológico , Humanos , Masculino , Conducta de Reducción del Riesgo
19.
Vaccine ; 40(34): 5050-5059, 2022 08 12.
Artículo en Inglés | MEDLINE | ID: mdl-35868948

RESUMEN

BACKGROUND: There is very little known about SARS-CoV-2 vaccine immune responses in New Zealand populations at greatest risk for serious COVID-19 disease. METHODS: This prospective cohort study assessed immunogenicity in BNT162b2 mRNA vaccine recipients in New Zealand without previous COVID-19, with enrichment for Maori, Pacific peoples, older adults ≥ 65 years of age, and those with co-morbidities. Serum samples were analysed at baseline and 28 days after second dose for presence of quantitative anti-S IgG by chemiluminescent microparticle immunoassay and for neutralizing capacity against Wuhan, Beta, Delta, and Omicron BA.1 strains using a surrogate viral neutralisation assay. RESULTS: 285 adults with median age of 52 years were included. 55% were female, 30% were Maori, 28% were Pacific peoples, and 26% were ≥ 65 years of age. Obesity, cardiac and pulmonary disease and diabetes were more common than in the general population. All participants received 2 doses of BNT162b2 vaccine. At 28 days after second vaccination, 99.6% seroconverted to the vaccine, and anti-S IgG and neutralising antibody levels were high across gender and ethnic groups. IgG and neutralising responses declined with age. Lower responses were associated with age ≥ 75 and diabetes, but not BMI. The ability to neutralise the Omicron BA.1 variant in vitro was severely diminished but maintained against other variants of concern. CONCLUSIONS: Vaccine antibody responses to BNT162b2 were generally robust and consistent with international data in this COVID-19 naïve cohort with representation of key populations at risk for COVID-19 morbidity. Subsequent data on response to boosters, durability of responses and cellular immune responses should be assessed with attention to elderly adults and diabetics.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Anciano , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Vacuna BNT162 , COVID-19/prevención & control , Femenino , Humanos , Inmunogenicidad Vacunal , Inmunoglobulina G , Masculino , Persona de Mediana Edad , Nueva Zelanda/epidemiología , Estudios Prospectivos , SARS-CoV-2 , Vacunas Sintéticas , Vacunas de ARNm
20.
Trials ; 23(1): 513, 2022 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-35725488

RESUMEN

BACKGROUND: Risks to mother and fetus following Ebola virus infection are very high. Evaluation of safety and immunogenicity of non-replicating Ebola vaccine candidates is a priority for use in pregnant women. This is the protocol for a randomized, open-label, single-center phase 3 clinical trial of the safety, reactogenicity, and immunogenicity of the 2-dose Ebola vaccine regimen in healthy adult pregnant women. This 2-dose regimen has been shown to be safe, judged effective, and approved in non-pregnant populations. METHODS: A total of 2000 adult (≥ 18 years of age) pregnant women will be enrolled from antenatal care facilities in Western Rwanda and randomized (1:1) to receive the 2-dose Ebola vaccine regimen (Ad26.ZEBOV, MVA-BN-Filo (group A)) or control (unvaccinated pregnant women (group B)). The primary objectives are to (1) assess adverse maternal/fetal outcomes in randomized pregnant women up to 1.5 months after delivery and (2) assess adverse neonatal/infant outcomes in neonates/infants born to randomized women up to 3.5 months after birth. The frequency and relatedness of all serious adverse events in women and newborns from randomization or birth, respectively, until study end will be reported. The reactogenicity and unsolicited adverse events of the 2-dose Ebola vaccine regimen in all vaccinated pregnant women (group A) will be reported. We will also assess the immunogenicity of the 2-dose Ebola vaccine regimen in 150 pregnant women who are anticipated to receive both vaccine doses within the course of their pregnancy (a subset of the 1000 pregnant vaccinated women from group A) compared to 150 non-pregnant women vaccinated after delivery (a subset of group B). The persistence of maternal antibodies in 75 infants born to women from the group A subset will be assessed. Exploratory analyses include assessment of acceptability of the 2-dose Ebola vaccine regimen among group A and assessment of maternal antibodies in breast milk in 50 women from group A and 10 controls (women from group B prior to vaccination). DISCUSSION: This study is intended to support a label variation to relax restrictions on use in pregnant women, a vulnerable population with high medical need. TRIAL REGISTRATION: Clinicaltrials.gov NCT04556526 . September 21, 2020.


Asunto(s)
Vacunas contra el Virus del Ébola , Fiebre Hemorrágica Ebola , Adulto , Ensayos Clínicos Fase III como Asunto , Vacunas contra el Virus del Ébola/efectos adversos , Femenino , Humanos , Recién Nacido , Embarazo , Mujeres Embarazadas , Ensayos Clínicos Controlados Aleatorios como Asunto , Vacunación/efectos adversos , Vacunación/métodos
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