CI

At a glance

ClinicalIndex Comparison Record
Phase 3Completed· 31,835 enrolled
Drug / intervention
Ad26.COV2.S +1 morebiological
Likely dose
Not stated in record
Structured eligibility isn't available for this trial yet — see the full criteria in the Eligibility tab below.

Standardized by ClinicalIndex from the ClinicalTrials.gov record · verify against the source.

Search/NCT04614948
NCT04614948Phase 3Completed
CompareCT.gov

A Randomized, Double-blind, Placebo-controlled Phase 3 Study to Assess the Efficacy and Safety of Ad26.COV2.S for the Prevention of SARS-CoV-2-mediated COVID-19 in Adults Aged 18 Years and Older

Janssen Vaccines & Prevention B.V.·interventional·Posted Nov 4, 2020·Updated Feb 4, 2025

In Brief

A Phase 3 clinical trial evaluating Ad26.COV2.S and Placebo for Participants With or Without Stable Co-morbidities Associated With Progression to Severe COVID-19. Completed, enrolled 31,835 participants across 126 sites in 10 countries.

Detailed Summary

The study will evaluate the efficacy of Ad26.COV2.S in the prevention of molecularly confirmed moderate to severe/critical coronavirus disease-2019 (COVID-19), as compared to placebo, in SARS-CoV-2 seronegative adults in the double-blind phase and to describe COVID-19 outcomes, safety, and immunogenicity in the different study cohorts in open-label phase.

Study Details

Study Typeinterventional
Allocation--
Masking--
Primary Purpose--
ConditionsParticipants With or Without Stable Co-morbidities Associated With Progression to Severe COVID-19
CountriesBelgium, Brazil, Colombia, France, Germany, Philippines, South Africa, Spain, United Kingdom, United States
Collaborators--

Timeline

Phase 3CompletedFinished
202120222023202420252026
First PostedNov 4, 2020
Enrollment StartNov 12, 2020
Primary CompletionJun 18, 2023
TodayJul 2, 2026
Enrollment to primary: 2.6 yearsPosted 5.7 years ago

Interventions

Ad26.COV2.Sbiological

Ad26.COV2.S vaccine will be administered on Day 1 and Day 57 in the double-blind phase. At unblinding visit Ad26.COV2.S vaccine will be administered to participants at Day 57 who have not yet received second vaccination and in newly enrolled participants as either single dose on Day 1 or two doses on Day 1 and Day 57. Single dose of Ad26.COV2.S vaccine will also be administered to participants initially receiving placebo. Single booster dose of Ad26.COV2.S vaccine will be given to participants in the open label phase who have received only a single vaccination with Ad26.COV2.S.

Placeboother

Placebo will be administered as IM injection on Day 1 and Day 57.