Immunogenicity and safety of a booster dose of the COVID-19 DNA vaccine in healthy adults aged 18 years and above: a single-center, randomized, observer-blind, placebo-controlled phase 2 trial.

ABSTRACT:

Background

A two-dose primary regimen of INO-4800 DNA vaccine demonstrated only modest immunogenicity in the previous phase 2 clinical trial. This booster study aimed to evaluate the immunogenicity and safety of a booster dose of INO-4800 in adults previously received two-dose regimen of INO-4800.

Methods

Healthy adults who received two doses of INO-4800 (1.0 mg or 2.0 mg) at least 12 months ago in a previous phase 2 trial were eligible for this booster study, conducted in Danyang, Jiangsu Province, China. Eligible participants were stratified by primary vaccination dose (1.0 mg or 2.0 mg) and age group (18-59 years or ≥ 60 years), and subsequently randomized in a 1:1 ratio to receive a third dose of INO-4800 or placebo at the same dosage as previously administered. The prim

SUBMITTER: Yao A 

PROVIDER: S-EPMC12103785 | biostudies-literature | 2025 May

REPOSITORIES: biostudies-literature