J&J advances COVID-19 vaccine into phase 3 testing

Johnson & Johnson has announced the launch of a large-scale phase 3 trial of its COVID-19 vaccine candidate – JNJ-78436735/Ad26.COV2.S – following positive interim results from a phase 1/2a clinical study of the shot.


In an interim analysis of results from the ENSEMBLE phase 1/2a trial, J&J’s vaccine demonstrated a promising safety profile and immunogenicity after a single dose.

Based on these early positive results, J&J is moving forward into a multi-country phase 3 trial, which plans to enrol up to 60,000 volunteers across three continents. The study will investigate the safety and efficacy of a single vaccine dose versus placebo in preventing COVID-19.

J&J’s COVID-19 candidate uses the company’s AdVac technology platform, which was also used to develop and manufacture the J&J’s existing Ebola vaccine, as well as construct its other investigational candidates for Zika, RSV and HIV.