A group of nine vaccine developers has announced a "historic pledge" to uphold scientific and ethical standards in the search for a coronavirus vaccine, APA reports citing BBC.
The firms, including Pfizer and Merck, said they would only apply for regulatory approval after vaccines went through three phases of clinical study.
It comes amid global debates about the safety of vaccines made this year.
US President Donald Trump has said he wants one available in the US before November's election.
No vaccine has yet completed clinical trials, according to the World Health Organization (WHO) - leading some scientists to fear the search for a vaccine is being politicised, and public trust could be damaged.
In their pledge, the nine biopharmaceutical firms did not mention Mr Trump but said they believed their action would "ensure public confidence" in the development of any inoculation.