Johnson & Johnson (J&J) has reported that the Phase III ENSEMBLE clinical trial of its single-dose Covid-19 vaccine candidate met all primary and key secondary endpoints.

The investigational vaccine is being developed by J&J’s subsidiary Janssen Pharmaceutical.

Dubbed ENSEMBLE, the Phase III trial was launched last September, and involved subjects aged 18 years and above, with and without comorbidities, in Argentina, Brazil, Chile, Colombia, Mexico, Peru, South Africa, and the US.

The safety and efficacy data are based on 43,783 participants accruing 468 symptomatic cases of Covid-19.

According to J&J, the single-shot candidate has been found to be 72% effective in the US and 66% effective overall at preventing ‘moderate to severe’ coronavirus.

Furthermore, it is 85% effective in preventing severe disease across all regions studied, 28 days after vaccination in all adults aged 18 years and above.

Once cleared for emergency use, the vaccine will be the first single-dose regimen introduced for commercial use.

Johnson & Johnson board of directors chairman and CEO Alex Gorsky said: “Johnson & Johnson embarked on the global effort to combat the Covid-19 pandemic a year ago, and has brought the full force of our capabilities, as well as tremendous public-private partnerships, to enable the development of a single-shot vaccine.

“Our goal all along has been to create a simple, effective solution for the largest number of people possible, and to have maximum impact to help end the pandemic.

“We’re proud to have reached this critical milestone and our commitment to address this global health crisis continues with urgency for everyone, everywhere.”

The latest results in the vaccine’s Phase III trials enabled J&J to become the fifth company supported by the US Government to develop an effective Covid-19 vaccine in less than a year.

J&J intends to file for EUA in the US early this month and expects to have ready-to-ship product immediately after authorisation.