Study reveals Moderna’s COVID-19 vaccine worked well on monkeys

DA study in the New England Journal of Medicine, Tuesday, disclosed that  a US biotech firm, Moderna’s COVID-19 vaccine induced a robust immune response and prevented the coronavirus from replicating in the noses and lungs of monkeys.

  It was noted that the fact that the vaccine prevented the virus from replicating in the nose is seen as particularly crucial in preventing it from being transmitted onward to others and that the same outcome did not occur when the University of Oxford’s vaccine was tested on monkeys, though that vaccine did prevent the virus from entering the animals’ lungs and making them very sick.

  In the Moderna animal study, three groups of eight rhesus macaques received either a placebo or the vaccine at two different dose levels — 10 micrograms and 100 micrograms.

  All vaccinated macaques produced high levels of neutralising antibodies that attack a part of the SARS-CoV-2 virus used to invade cells.

  Notably, monkeys receiving both dose levels produced these antibodies at levels higher than those found in humans who have recovered from COVID-19.

  According to authors, the vaccine also induced the production of a different immune cell known as T-cells that may have helped boost the overall response.

  A major area of concern is that vaccines under development could actually backfire by amplifying rather than suppressing the disease.

  So-called vaccine-associated enhancement of respiratory disease (VAERD) has been linked to the production of a specific type of T-cell known as Th2 — but these cells were not produced during the experiment, suggesting this vaccine won’t backfire.

  Four weeks after the monkeys received their second injection, they were exposed to the SARS-CoV-2 virus, both through the nose and directly to the lungs via a tube.

  After two days, no replicating virus was detected in the lungs of seven of the eight macaques in both the low and high dose groups.