Publications by authors named "Dirk Heerwegh"

Identifying immune correlates of risk following COVID-19 vaccine boosters has become paramount as a result of the challenges in generating additional efficacy data. The trial data described here was collected in the United States, with a large part of the study conduct coinciding with the emergence of the SARS-CoV-2 Omicron BA.1 variant.

View Article and Find Full Text PDF

COVID-19 vaccine boosters may optimize durability of protection against variants of concern (VOCs). In this randomized, double-blind, phase 2 trial, participants received 3 different dose levels of an Ad26.COV2.

View Article and Find Full Text PDF

Without clinical efficacy data, vaccine protective effect may be extrapolated from animals to humans using an immunologic marker that correlates with protection in animals. This immunobridging approach was used for the two-dose Ebola vaccine regimen Ad26.ZEBOV, MVA-BN-Filo.

View Article and Find Full Text PDF

Background: The Pediatric Respiratory Syncytial Virus Electronic Severity and Outcome Rating System (PRESORS) was developed to assess the severity of respiratory syncytial virus (RSV) infection in children. Because young children cannot report how they feel or function, ratings are based on observations by the child's caregiver (Observer-Reported Outcome questionnaire [ObsRO]) and clinician (Clinician-Reported Outcome questionnaire [ClinRO]). This prospective study aimed to evaluate the psychometric properties of the PRESORS.

View Article and Find Full Text PDF
Article Synopsis
  • Ad26.COV2.S is an effective single-dose COVID-19 vaccine that provides stable antibody levels for at least 8-9 months and immune memory, regardless of age.
  • Booster doses significantly increase binding and neutralizing antibody levels, with a robust response observed 7 days post-boost.
  • The study indicates that boosting enhances the vaccine's effectiveness, especially against viral variants like Beta, showing strong potential for long-term immunity.
View Article and Find Full Text PDF

This secondary analysis of the phase 3 ENSEMBLE trial (NCT04505722) assessed the impact of preexisting humoral immunity to adenovirus 26 (Ad26) on the immunogenicity of Ad26.COV2.S-elicited severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific antibody levels in 380 participants in Brazil, South Africa, and the United States.

View Article and Find Full Text PDF
Article Synopsis
  • The study aimed to evaluate the safety, tolerability, and immune response of a two-dose Ebola vaccine regimen (Ad26.ZEBOV and MVA-BN-Filo) in adolescents and children in Africa, due to recurring Ebola outbreaks causing significant health issues.
  • Conducted in multiple centers across Eastern and Western Africa, the research involved 263 participants aged 4 to 17, with a random allocation of vaccine or placebo, monitoring for adverse events and immune responses over one year.
  • Results showed no serious vaccine-related adverse events, mostly mild to moderate side effects, and demonstrated a strong immune response, with 100% of vaccinated participants developing binding antibodies against the Ebola virus.
View Article and Find Full Text PDF

SARS-CoV-2 Spike-specific binding and neutralizing antibodies, elicited either by natural infection or vaccination, have emerged as potential correlates of protection. An important question, however, is whether vaccine-elicited antibodies in humans provide direct, functional protection from SARS-CoV-2 infection and disease. In this study, we explored directly the protective efficacy of human antibodies elicited by Ad26.

View Article and Find Full Text PDF

Background: We investigated safety, tolerability, and immunogenicity of the heterologous 2-dose Ebola vaccination regimen in healthy and HIV-infected adults with different intervals between Ebola vaccinations.

Methods And Findings: In this randomised, observer-blind, placebo-controlled Phase II trial, 668 healthy 18- to 70-year-olds and 142 HIV-infected 18- to 50-year-olds were enrolled from 1 site in Kenya and 2 sites each in Burkina Faso, Cote d'Ivoire, and Uganda. Participants received intramuscular Ad26.

View Article and Find Full Text PDF

Background: The Ebola epidemics in west Africa and the Democratic Republic of the Congo highlight an urgent need for safe and effective vaccines to prevent Ebola virus disease. We aimed to assess the safety and long-term immunogenicity of a two-dose heterologous vaccine regimen, comprising the adenovirus type 26 vector-based vaccine encoding the Ebola virus glycoprotein (Ad26.ZEBOV) and the modified vaccinia Ankara vector-based vaccine, encoding glycoproteins from Ebola virus, Sudan virus, and Marburg virus, and the nucleoprotein from the Tai Forest virus (MVA-BN-Filo), in Sierra Leone, a country previously affected by Ebola.

View Article and Find Full Text PDF

Background: Children account for a substantial proportion of cases and deaths from Ebola virus disease. We aimed to assess the safety and immunogenicity of a two-dose heterologous vaccine regimen, comprising the adenovirus type 26 vector-based vaccine encoding the Ebola virus glycoprotein (Ad26.ZEBOV) and the modified vaccinia Ankara vector-based vaccine, encoding glycoproteins from the Ebola virus, Sudan virus, and Marburg virus, and the nucleoprotein from the Tai Forest virus (MVA-BN-Filo), in a paediatric population in Sierra Leone.

View Article and Find Full Text PDF

The Ad26.COV2.S vaccine has demonstrated clinical efficacy against symptomatic COVID-19, including against the B.

View Article and Find Full Text PDF

Importance: Control of the global COVID-19 pandemic will require the development and deployment of safe and effective vaccines.

Objective: To evaluate the immunogenicity of the Ad26.COV2.

View Article and Find Full Text PDF

Replication-incompetent adenoviral vectors have been under investigation as a platform to carry a variety of transgenes, and express them as a basis for vaccine development. A replication-incompetent adenoviral vector based on human adenovirus type 26 (Ad26) has been evaluated in several clinical trials. The Brighton Collaboration Viral Vector Vaccines Safety Working Group (V3SWG) was formed to evaluate the safety and features of recombinant viral vector vaccines.

View Article and Find Full Text PDF

Background: Zika virus (ZIKV) may cause severe congenital disease after maternal-fetal transmission. No vaccine is currently available.

Objective: To assess the safety and immunogenicity of Ad26.

View Article and Find Full Text PDF

Background: Efficacious vaccines are urgently needed to contain the ongoing coronavirus disease 2019 (Covid-19) pandemic of infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). A candidate vaccine, Ad26.COV2.

View Article and Find Full Text PDF

Background: Malaria remains a major global public health concern, especially in sub-Saharan Africa. The RTS,S/AS01 malaria candidate vaccine was reviewed by the European Medicines Agency and received a positive scientific opinion; WHO subsequently recommended pilot implementation in sub-Saharan African countries. Because malaria and HIV overlap geographically, HIV-infected children should be considered for RTS,S/AS01 vaccination.

View Article and Find Full Text PDF

Methods: In an observer blind, phase 2 trial, 55 adults were randomized to receive one dose of Ad35.CS.01 vaccine followed by two doses of RTS,S/AS01 (ARR-group) or three doses of RTS,S/AS01 (RRR-group) at months 0, 1, 2 followed by controlled human malaria infection.

View Article and Find Full Text PDF