|
 When exposed to the virus, six out of six animals who got the
vaccine candidate were completely protected from lung disease and
five out of six were protected from infection as measured by the
presence of virus in nasal swabs, according to the study published
in the journal Nature.
"This gives us confidence that we can test a single-shot vaccine in
this epidemic and learn whether it has a protective effect in
humans," Dr. Paul Stoffels, J&J's chief scientific officer, told
Reuters in a telephone interview.
The drugmaker said it had started early-stage human trials in the
United States and Belgium and would test its vaccine candidate in
over 1,000 healthy adults aged 18 to 55 years, as well as adults
aged 65 years and older.
The U.S. government is backing J&J's vaccine effort with $456
million in funding as part of a spending spree aimed at speeding
production of a vaccine to end the pandemic, which has infected
millions and killed more than 660,000 people.
Stoffels said prior tests of this type of vaccine in other diseases
found that a second shot significantly increases protection. But in
a pandemic a single-shot vaccine has a significant advantage,
sidestepping a lot of the logistical issues involved in getting
people to come back for their second dose.
The company plans to take up the question of one or two doses in its
phase 1 trial.
Depending on those results, J&J plans to start large-scale, phase 3
testing with a single-shot regimen in the second half of September.
Around the same time, the company will start a parallel phase 3
study testing a two-shot regimen of the vaccine, Stoffels said.
[to top of second column] |
J&J's vaccine uses a common cold virus known as adenovirus type 26 or Ad26 to
ferry coronavirus proteins into cells in the body, causing the body to mount an
immune defense against the virus.
In the monkey study, scientists from J&J and Harvard's Beth Israel Deaconess
Medical Center studied seven different potential vaccines in 32 animals and
compared the results to 20 control animals who got placebo shots.
Six weeks later, all of the animals were exposed to the SARS-CoV-2 virus. All 20
animals that received the placebo developed high levels of virus in their lungs
and nasal swabs.
In the best-performing candidate, which J&J selected for human testing, none of
the animals had virus in their lungs and only one showed low levels of virus in
nasal swabs. Lab tests showed they all had developed antibodies capable of
neutralizing the virus after a single shot.
"This study shows that even just a single immunization with the Ad26 vaccine
leads to neutralizing antibody responses and robust protection of monkeys
against COVID-19," said Dr. Dan Barouch, a vaccine researcher at Beth Israel
Deaconness who led the research in collaboration with J&J.
J&J shares were up nearly 2% at $149.72 before the bell on Thursday.
(Reporting by Julie Steenhuysen in Chicago; Additional reporting by Ankur
Banerjee in Bengaluru; Editing by Richard Pullin and Shounak Dasgupta)
[© 2020 Thomson Reuters. All rights
reserved.] Copyright 2020 Reuters. All rights reserved. This material may not be published,
broadcast, rewritten or redistributed.
Thompson Reuters is solely responsible for this content.
 |
