Johnson & Johnson started their United States human safety trials for its COVID-19 vaccine candidate on Thursday, after relatively successful studies on the vaccine’s effect on monkeys.
The vaccine chosen during the study on monkeys was the best-performing vaccine candidate, with it offering very strong protection in just one dose.
During the study, all six animals who got the vaccine candidate were fully protected from different lung diseases, whilst five out of six animals were protected from infection that was present because of a virus, with the latter being tested through nasal swabs.
The study was published in the journal Nature.
In an interview with Reuters, Johnson & Johnson’s chief scientific officer Dr Paul Stoffels said that the tests give the company “confidence that we can test a single-shot vaccine in this epidemic and learn whether it has a protective effect in humans”.
The multinational corporation claimed that it had commenced very early-stage human trials in the United States and Belgium, aiming to test the candidate in over 1,000 healthy adults who are aged 18 to 55 years.
The corporation also aims to test the vaccine candidate on adults that are 65-years-old and older.
The United States government is backing Johnson & Johnson’s efforts to formulate a vaccine, providing the corporation with $456 million (€387.90 million) in funding, as the government continues to spend more on several companies to speed the production of a vaccine.
As of July 29, the United States has had 4,568,037 cases of COVID-19, with 2,169,153 active cases and 153,840 deaths.
Stoffels also added that previous tests of this type of vaccine in other diseases showed that a second shot added to the initial one significantly adds to protection against the diseases.
However, during a pandemic, a single-shot vaccine is very advantageous, as it avoids the need for people to return for a second dose of the vaccine.
The company is planning on tackling the question of whether to offer one or two doses during its first phase of trials.
Depending on the results of the trials, Johnson & Johnson aim to start their third phase of testing for the single-shot vaccine candidate in the second half of September, with the company also starting their third phase of testing for two shots of the vaccine, Stoffels claimed.
The vaccine candidate being utilised makes use of a common cold virus, referred to as adenovirus type 26 or Ad26 to ferry coronavirus proteins into cells found in the body, which will then cause the body to form an immune system which defends the body against the virus.
During the monkey study, scientists from both Johnson & Johnson and Harvard’s Beth Israel Deaconess Medical Centre researched seven different types of medical drugs that have the potential to become vaccines in 32 animals.
These were then compared to the results of 20 control animals that were given placebo shots.
Just six weeks later, all of the animals were then exposed to COVID-19, with all of the 20 animals that received these placebo shots developing very high levels of the virus in their lungs, found through nasal swabs.
After the best-performing vaccine candidate was used, none of the animals had the virus in their lungs, with just one animal having very low levels of the virus after nasal swabbing. According to lab tests, all of the animals had developed antibodies that were capable of neutralising the virus after just one shot of the potential vaccine.
Dr Dan Barouch, a vaccine researcher at Beth Isreal Deaconness claimed that “This study shows that even just a single immunisation with the Ad26 vaccine leads to neutralising antibody responses and robust protection of monkeys against COVID-19.”