Hong Kong will resume administering the Pfizer/BioNTech coronavirus jab on Monday after the pharma giant said a packaging flaw that temporarily halted its use did not affect its safety, officials said.
The financial hub suspended use of the German-made vaccine last month when Fosun, its China distributor, informed authorities that some vial caps were defective.
It was a blow to the roll-out of mass vaccination programmes against a deadly virus that has killed more than 2.7 million people around the world and hammered the global economy.
"BioNTech told us that the batch of vaccines concerned did not have quality and safety problem," Hong Kong's civil service chief Patrick Nip, who has been leading the government's cross-department anti-virus initiative, said Thursday.
"Administration of the BioNTech vaccines will resume on Monday," he said, adding that a new batch of 300,000 doses would arrive in the city on Friday.
Health authorities in Hong Kong had previously stressed that any defective bottles were discarded before being given out, and that they paused the programme temporarily out of an abundance of caution.
More than 180,000 residents who reserved Pfizer/BioNTech vaccinations were affected by the 12-day suspension, including some 30,000 people who were due to receive their second jab within the recommended 21-day window.
Citing BioNTech's own analysis, Hong Kong's health director Constance Chan said the problem in some vials had been traced to how caps reacted to the minus 70 degrees Celsius temperatures the vaccine must be kept in for storage.
When the vials were defrosted to be prepared for administering, she said, air sometimes leaked in.
Officials said the new batch of vaccines arriving in Hong Kong on Friday had been manufactured in another factory in Germany where over 15,000 vials were tested and no defects were found.
More than 460,000 residents of Hong Kong have received their first jab of coronavirus vaccines since the campaign kicked off over one month ago, accounting for about seven percent of the city's population aged 16 and above.
"It's still far from our immunity target," Nip said. "We appeal to all eligible members of the public to get vaccinated."
Authorities currently offer China's Sinovac and the Pfizer/BioNTech vaccine.
Sinovac received fast-track approval despite not publishing peer-reviewed clinical data.
The data available points to an efficacy rate of between 50-80 percent, depending on the studies.
Pfizer says its efficacy rate is 94-95 percent.