Sources told Reuters that enrollment of new patients and other trial procedures for the pivotal U.S. trial were being rescheduled until at least midweek and that it was not clear how long it would take for the FDA to complete its probe.
Bourla, however, said the availability of the COVID19 vaccine before 2020 would depend upon the safety data and approval from the United States regulator Food and Drug Administration (FDA).
Coronavirus Vaccine latest: Pfizer-BioNTech's BNT162mRNA vaccine is an mRNA vaccine.
"It's really one of the safety valves that you have on clinical trials such as this", he told "CBS This Morning". "So it's unfortunate that it happened. Hopefully they'll work it out and be able to proceed along with the remainder of the trial". But for most people, they will not have access to a vaccine until 2021.
In its statement over the weekend, AZ said it "cannot disclose further medical information", about why it halted, but added that: "All trial investigators and participants will be updated with the relevant information and this will be disclosed on global clinical registries, according to the clinical trial and regulatory standards".
A viable vaccine to the coronavirus responsible for the COVID-19 illness won't be available to immunize the general public until the end of 2024, said the chief executive of the world's largest vaccine manufacturer in an exclusive interview with the Financial Times.
The British adverse event involved a study patient thought to be suffering a rare spinal inflammatory disorder called transverse myelitis. The trials also assess effectiveness by tracking who gets sick and who doesn't between patients getting the vaccine and those receiving a dummy shot.
Dr Chiu said: "We have evidence that delivering influenza vaccines via a nasal spray can protect people against flu as well as help to reduce the transmission of the disease".
The World Health Organization has cited AZD1222, replication-deficient chimpanzee viral vector based on a weakened version of a common cold virus which contains the genetic material of the SARS-CoV-2 virus spike protein, as a leading contender in the race for a vaccine.
Italy's health minister, Roberto Speranza, welcomed the resumption of the vaccine trial, but warned that prudence was still necessary.