Officials and experts have expressed concern that the regulatory approval process overseen by the Food and Drug Administration (FDA) will be undermined by political pressure, and around a quarter of Americans say they are hesitant to take a COVID-19 vaccine.
"As this trial resumes, I am hoping the message communicated to the public is that we are following procedures to highest ethical standard and not interfering with the FDA regulatory process," said Matthew Hepburn, head of vaccine development for Operation Warp Speed, a public-private partnership to speed inoculation efforts.
Infections are rising in 80 countries people in the northern hemisphere spend more time indoors with winter approaching.
J&J said on Friday that the safety panel, called a Data and Safety Monitoring Board, has recommended that the drugmaker resume trial recruitment after finding no evidence that the vaccine caused the volunteer to fall ill.
J&J expects to resume its trial in the United States on Monday or Tuesday and remains on track to produce data from the trial on the vaccines' effectiveness by the end of 2020 or early 2021, J&J's chief scientific officer Paul Stoffels said.
J&J is also in discussions with other regulators to resume a trial outside of the United States, the company said.
So far, the medical board has not identified a clear cause for the patients' illness. J&J cannot reveal any details about the patient's sickness because of patient privacy rules, Stoffels said.
AstraZeneca said that it is not unusual for some trial participants to fall ill during large scale vaccine trials but that the US Food and Drug Administration has reviewed all safety data from the trials globally and deemed it safe to continue testing the vaccine.
AstraZeneca trials in the United Kingdom, Brazil and South Africa resumed last month even as the US Food and Drug Administration continued its investigation into the case.
Reuters earlier this week reported that the FDA had completed its review and that the AstraZeneca US trial was set to resume as early as this week, citing four sources familiar with the situation.
AstraZeneca's vaccine is being developed along with researchers at Oxford University.