World Health Organization's chief scientist, Soumya Swaminathan said that AstraZeneca's pause of an experimental vaccine for the coronavirus after the illness of a participant is a "wake-up call" but should not discourage researchers.
"This is a wake-up call to recognize that there are ups and downs in clinical development and that we have to be prepared," she said.
"We do not have to be discouraged. These things happen." She added.
Governments are desperate for a vaccine to help end the COVID-19 pandemic, which has caused more than 900,000 deaths and global economic turmoil, and the WHO had flagged AstraZeneca's, being developed with Oxford University, as the most promising.
However, the drugmaker suspended late-stage trials this week after a participant in Britain suffered from neurological symptoms.
Mike Ryan, WHO's head of emergencies added, "It's a race against this virus, and it's a race to save lives. It's not a race between companies, and it's not a race between countries,"
More than 27.95 million people have been reported infected globally.
“A combination of factors is helping reduce death rates in Europe, including finding cases earlier and better clinical care,” said WHO epidemiologist Maria Van Kerkhove.
"We are in a better position to prevent the virus from infecting vulnerable populations," she said, cautioning, however, that the disease's long-term effects were still not known.
WHO General Director Tedros Adhanom Ghebreyesus said, "What worries me the most is what I have been saying all along: a lack of solidarity. When we are divided, it is a good opportunity for the virus."