Single Dose Johnson & Johnson Vaccine Proves 66% Effective In Large Trial

Covid-19 - Lab Technician - Courtesy J & J.

A fifth covid-19 vaccine, produced by the US pharma giant Johnson & Johnson, has shown efficacy against the coronavirus and could transform prospects for protecting people, due to the need for a single dose only.

The vaccine, made by the US giant’s subsidiary Janssen, based in the Netherlands, was trialled in the UK. The EU has ordered 400m doses.

Trial results show 72% efficacy in preventing Covid in the US but a lower rate of 66% was observed globally in the large trial conducted across three continents and against multiple variants.


The results had been much anticipated, because the Janssen vaccine can be given as a single injection.

Single dose vaccines means stocks will naturally go further, and particularly in lower-income countries an immunisation programme will be easier as there is no need for a recall after three or 12 weeks.

Walid Gellad, a health policy associate professor at the University of Pittsburgh said “Right now, any protection and additional vaccine is great. The ‘South Africa’ strain is still uncommon in the US and obviously we would want to see higher efficacy, but the key is not only overall efficacy but specifically efficacy against severe disease, hospitalisation, and death

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