GENEVA – The World Health Organization (WHO) welcomed a report by Moderna on Monday that its experimental vaccine had showed 94.5% efficacy, but said that “many questions” remained and that it was no time for complacency.
Only very limited amounts of any vaccine will be available in the first half of 2021 for people other than priority health workers, WHO officials said.
“While we continue to receive encouraging news about COVID-19 vaccines and remain cautiously optimistic about the potential for new tools to start to arrive in coming months, right now we are extremely concerned by the surge in cases we are seeing in some countries, particularly in Europe and the Americas,” WHO director-general Tedros Adhanom Ghebreyesus told a news briefing.
The comments marked his return to the Geneva agency from quarantine after being exposed to COVID-19 virus some 17 days ago. Tedros said he had no symptoms and had seen no need for a test.
Moderna Inc.’s experimental vaccine is 94.5% effective in preventing COVID-19 based on interim data from a late-stage trial, the company said Monday, becoming the second U.S. drugmaker to report results that far exceed expectations.
Together with Pfizer Inc.’s vaccine, which is also more than 90% effective, and pending more safety data and regulatory review, the United States could have two vaccines authorized for emergency use in December with as many as 60 million doses of vaccine available this year.
Soumya Swaminathan, WHO chief scientist, said that the Moderna results were “quite encouraging.” Its final efficacy and safety profile would still be needed, as well as a follow-up on trial participants over two months to check for any side effects.
Pfizer and Moderna candidate vaccines both use mRNA technology and appear to achieve high efficacy, she added.
“But there are many, many questions still remaining about the duration of protection, the impact on severe disease, the impact on different sub-populations — especially the elderly — as well as the adverse events beyond a certain period of time,” Swaminathan said.
Clinical trials must continue to collect more data, she added, noting that more results were expected in coming weeks from other vaccine trials.
“We are looking at at least the first half of the year as being a period with very, very limited doses. Supplies are going to be limited, there are bilateral deals that many of the companies have done, so many of the doses have already been booked by some countries,” Swaminathan said.
Moderna is a two-dose vaccine and its delivery means, as well as storage, were also important considerations, said Kate O’Brien, director of WHO’s immunization department.
“We will be looking really carefully at the ease at which different vaccines can be delivered and certainly about the number of doses that are required,” she said.
In a time of both misinformation and too much information, quality journalism is more crucial than ever.
By subscribing, you can help us get the story right.