London, Nov. 10, 2020 (AltAfrica)-BioNTech co-founder and chief executive said he was optimistic that the protective effect of its experimental Covid-19 vaccine, co-developed with Pfizer, would last for at least a year.

The two companies earlier on Monday became the first drug makers to release successful trial data, saying their vaccine was shown to be more than 90% effective, a major victory in the fight against the pandemic.

Scientists said initial trial results for Pfizer Inc and BioNTech’s coronavirus vaccine far outpaced their expectations for protection against a completely new disease, but that many questions remain unanswered.

Scientists also want to understand whether the Pfizer vaccine fully prevents people from getting infected with the new coronavirus – a huge advantage in reducing transmission – or if it simply reduces the degree to which they become ill.

While it was not yet known how long the protection would last, he said research on recovered patients had shown that those with high antibodies levels to begin with have not experienced a sharp drop in those levels, and the same would likely go for vaccinated people.

“We should be more optimistic that the immunisation effect can last for at least a year,” CEO Ugur Sahin told Reuters.

Highlighting the logistical challenge of distributing the vaccine, which belongs to a class known as messenger RNA, the arrangement for the first three months would be that the genetic compound would have to be shipped and centrally stored at minus 70 degrees Celsius.

“Ideally, we want to be able to completely protect from infection, but I think we all accept that these so-called first generation vaccines are more likely to prevent disease,” said Lawrence Young, a professor of molecular oncology at Britain’s University of Warwick. “And the subtlety there, which is important, is if you’re infected then you can still transmit the virus.”

For transport to and at the site of administration it can be kept for up to five days at fridge temperatures, Sahin said, adding he was confident logistics would work very well.

“By December we expect more data (on the molecular stability), and if those results allow us to keep the vaccine in a fridge for longer than five days, maybe two weeks, that would again simplify things.”