Single Dose COVID-19 vaccine from Johnson & Johnson reports varied results

By Rahul Vaimal, Associate Editor
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American drug manufacturer Johnson & Johnson (J&J) has revealed mixed efficacy results to its much anticipated single-shot COVID-19 vaccine. 

Trial results showed that the vaccine which was tested in the US and seven other countries was 85 percent effective against COVID-19 with the most serious symptoms while it was only deemed to be 66 percent capable overall at preventing moderate to severe illness.

The Geographical Variation 

The J&J COVID-19 vaccine was found to be functioning better in the US (72 percent efficacy against moderate to severe COVID-19) compared to 57 percent in South Africa where it was tested against the new highly contagious variant.

J&J’s lower efficacy but single dosage vaccine could lure nations to prefer it over vaccines that have higher efficiency but require two dosages. A single dose vaccine could be easier to administer to a larger population and could lead to a faster rollout.

The drugmaker will soon seek emergency use permission from US authorities and is expected to supply 100 million doses in the country by June.

Initial Findings 

The yet to be completed 44,000 volunteer trial revealed that after 28 days, no one who got vaccinated needed hospitalization or died regardless of whether they were exposed to the regular coronavirus or the newly identified highly contagious variants.

The J&J vaccine transfers genetic instructions for human cells to create a specific protein of the coronavirus, in order to train the immune system for the live virus. The Oxford vaccine developed by British-Swedish vaccine manufacturer AstraZeneca too uses a similar methodology for its two-dose vaccine.

Both vaccines are highly portable as they can be stored in a refrigerator, unlike Pfizer-BioNTech and Moderna vaccines which need deep freeze solutions for storage and transportation.