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Johnson & Johnson’s Global Phase 3 ENSEMBLE Trial of its Janssen COVID-19 Vaccine Candidate Commences in South Africa

Johnson & Johnson has announced commencement of the pivotal Phase 3 ENSEMBLE trial of its investigational Janssen COVID-19 vaccine in South Africa. The first South African ENSEMBLE participants were dosed last week Friday, with the study also ongoing in the US, Brazil, Chile, Colombia and Argentina.

The global Phase 3 ENSEMBLE study is a randomized, double-blind, placebo-controlled clinical trial designed to evaluate the safety and efficacy of a single vaccine dose versus placebo in up to 60,000 adults of 18 years old and older, including significant representation from those that are over the age of 60. The trial will also include those with and without comorbidities associated with an increased risk for progression to severe COVID-19.

The initiation of the ENSEMBLE trial followed positive interim results from the Company’s Phase 1/2a clinical study, which demonstrated that the safety profile and immunogenicity after a single vaccination were supportive of further development. These results were published on medRxiv on 25 September 2020.  

Built on a legacy of purpose-driven actions and a commitment to diversity and inclusion, Johnson & Johnson aims to achieve broad representation of participants, including older adults and ethnically diverse populations, in the implementation of its COVID-19 Phase 3 trial program. In South Africa, the study will take place across approximately 31 trial sites, in locations with a high incidence of COVID-19. Site locations will include Gauteng, North West, Eastern Cape, Western Cape, Limpopo, Mpumalanga, and the Free State. The locations of sites were determined in close collaboration with local health authorities, taking into account current disease prevalence, population demographics and regulatory authorities’ requirements.

Johnson & Johnson is committed to bringing an affordable vaccine to the public on a not-for-profit basis for emergency pandemic use, provided the vaccine is demonstrated to be safe and effective and following regulatory approval.

For more information on Johnson & Johnson’s multi-pronged approach to combatting the pandemic, visit: