Johnson & Johnson enters late-stage trial testing its coronavirus vaccine

Johnson & Johnson has begun its phase three trial testing its potential coronavirus vaccine, the pharmaceutical company announced Wednesday.

J&J is the fourth drugmaker backed by the Trump administration's Covid-19 vaccine program Operation Warp Speed to enter late-stage testing. The other companies are Moderna, Pfizer and AstraZeneca.

The trial will enroll up to 60,000 adult volunteers across 215 locations in the U.S. and other countries, according to the National Institute of Allergy and Infectious Diseases. Participants will be randomly selected to receive a dose of the potential vaccine or a placebo, according to details of the trial, which will determine whether the vaccine is safe and effective.

"Four COVID-19 vaccine candidates are in Phase 3 clinical testing in the United States just over eight months after SARS-CoV-2 was identified," NIAID Director Dr. Anthony Fauci said in a statement.

"This is an unprecedented feat for the scientific community made possible by decades of progress in vaccine technology and a coordinated, strategic approach across government, industry and academia," he said. "It is likely that multiple COVID-19 vaccine regimens will be required to meet the global need. The Janssen candidate has showed promise in early-stage testing and may be especially useful in controlling the pandemic if shown to be protective after a single dose."

J&J has said it is using the same technologies it used to make its experimental Ebola vaccine. It involves combing genetic material from the coronavirus with a modified adenovirus that is known to cause common colds in humans.

Preclinical studies have shown J&J's potential Covid-19 vaccine can generate a promising response in nonhuman primates and hamsters. 

Paul Stoffels, J&J's chief scientific officer, told reporters on a conference call Tuesday that early-stage trial data, which will be released "imminently," shows the immune response in humans was "comparable to animals, which were protected." He also said the vaccine appeared to be well-tolerated, with symptoms such as fever resolving within 48 hours.

He said it will likely take six weeks to two months to reach 60,000 participants, allowing J&J to recruit a diverse cohort. The trial will include those both with and without comorbidities associated with an increased risk for progression to severe Covid-19, and will aim to enroll participants in Argentina, Brazil, Chile, Colombia, Mexico, Peru, South Africa and the United States.

"There are a lot of what we call 'readiness cohorts,' where we have predetermined in high risk areas the specific populations we want to target," he said. "The data teams have been working hard to find out where in the U.S., where in other parts of the world, we can get access to the people and parts of the population at high risk and diverse, which we need to have in the clinical trials." 

The development comes as President Donald Trump says the U.S. could find a safe and effective vaccine by the end of October and have enough vaccine doses to inoculate every American by April.

Asked which drugmaker could be the first to win U.S. approval, Trump told "Fox News" on Monday that Pfizer, Moderna and AstraZeneca are progressing well. He added J&J's vaccine will "probably be a little later." 

The U.S. Department of Health and Human Services announced on Aug. 5 that it reached a deal with Janssen, J&J's pharmaceutical subsidiary, worth approximately $1 billion for 100 million doses of its vaccine. The deal gives the federal government the option to order an additional 200 million doses, according to the announcement. 

The phase three trial will be jointly funded by J&J, the National Institutes of Health and NIAID, Stoffels said Tuesday. 

J&J has previously said it anticipates possible vaccine batches for a potential emergency use authorization available in early 2021. The company said it has continued the scaling up of its manufacturing capacity and remains on track to meet its goal of providing a billion doses of a vaccine each year.

Public health officials and infectious disease experts say world leaders will need an array of drugs and vaccines to defeat the virus, which emerged less than 10 months ago.