The Drug Administration of Vietnam (DAV) has agreed to extend the expiry of two Pfizer-BioNTech COVID-19 vaccine lots from six to nine months when the vaccine is stored at ultra-cold temperatures.
Vials of two vaccine lots, 124001 and 123002, can remain in use for three months beyond the November 30, 2021 expiry date printed on their labels as long as storage conditions between -90 and -60 degrees Celsius are maintained, the DAV said in a document dated October.
The new expiration date is February 28, 2022, it added. The lots' original shelf life is six months.
The conditional extension is guaranteed by Pfizer Vietnam and based on a conclusion from an advisory board, the drug administration noted.
According to the Vietnamese drug regulator, the vaccine producers had had enough time to do research and are able to provide evidence that supports the expiration extension to nine months.
The United States and most other countries had also approved such an extension, it added.
The U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA) gave the green light to a similar extension in September.
“The extension was rigorously tested to ensure safety, efficacy, and quality [of the vaccine],” Phan Trong Lan, director of Vietnam's Department of Preventive Medicine, said in a press statement on Tuesday.
The batches, totaling 2.96 million doses, are being administered to children between 12 and 17 years old across the country, including the capital city of Hanoi.
On Tuesday, some parents were concerned to see 'November 30, 2021' as the expiry date of the vaccine vials, which was the same date when their children were getting the shot, local newspaper Nguoi Lao Dong (Laborers) reported.
The National Institute of Hygiene and Epidemiology, which distributed the vaccine vials, has asked that medical workers inform parents of the extension to “avoid misunderstanding about the vaccine expiration date."
In a document issued on Monday, Pfizer Vietnam reaffirmed that the new expiry date for lots 124001 and 123002 is February 28, 2022.
The institute also requested that inoculation be expedited to ensure effective use of available vaccines and prevent disposal of expired batches.
More than 122 million COVID-19 vaccine doses have been administered in Vietnam since inoculation began on March 8.
Over 71 of the country’s 98 million people have got at least one dose while nearly 51 million are now fully vaccinated.
Vietnam aims to fully inoculate 100 percent of its adult population this year. Many provinces and cities in the country are immunizing children aged 12-17 against COVID-19, using Pfizer-BioNTech shots.