Moderna has said it will apply for US and European emergency authorisation of its Covid-19 vaccine based on full results from a late-stage study showing its vaccine was 94.1% effective with no serious safety concerns.
It also reported a 100% success rate in preventing severe cases. The filing sets Moderna's product up to be the second vaccine likely to receive US emergency use authorisation this year.
"We believe that we have a vaccine that is very highly efficacious. We now have the data to prove it," Moderna Chief Medical Officer Dr Tal Zaks said in a telephone interview.
"We expect to be playing a major part in turning around this pandemic."
Dr Zaks said he was emotional after seeing the 94.1% result over the weekend.
"It was the first time I allowed myself to cry. At this level of effectiveness, when you just do the math of what it means for the pandemic that's raging around us, it's just overwhelming," he said.
Moderna's announcement follows news from Pfizer and German partner BioNTech that their vaccine, which also uses a new technology called synthetic messenger RNA (mRNA), was 95% effective.
Pfizer has applied for emergency use authorisation, putting it about a week ahead of Moderna.
In addition to filing its US application, Moderna said it would apply for conditional approval from the European Medicines Agency, which has already begun a rolling review of data, and would continue to talk with other regulators conducting rolling reviews.
Moderna's latest efficacy result is slightly lower than an interim analysis released on 16 November of 94.5% effectiveness, a difference that Dr Zaks said is not statistically significant.
Both the Moderna and Pfizer vaccines proved more effective than anticipated and far superior to the 50% benchmark set by the US Food and Drug Administration.
Britain's AstraZeneca has announced an average efficacy rate of 70% for its vaccine and as much as 90% for a subgroup of trial participants who got a half dose first, followed by a full dose.
But some scientists have expressed doubts about the robustness of the 90% efficacy figure for the smaller group.
Independent advisers to the US Food and Drug Administration are scheduled to meet on 17 December to review Moderna's trial data and make a recommendation to the FDA. They will meet on 10 December to review Pfizer's data.
Mandatory vaccine 'not the way forward'
A senior lecturer in Biochemistry at UCC has said she does not believe that mandatory vaccination is a way forward or a good way out of this pandemic.
Dr Anne Moore told RTÉ's Six One News that "forcing something onto people who are not willing to have it" is not a good way of approaching vaccination and has not worked in many countries.
She said the key is for everyone to have all the information they need so they can make an informed decision about being vaccinated.
Dr Moore said it is also about creating a societal approach so society as a whole agrees that vaccination is a good way forward and a good way out of this pandemic.
Ireland's High-Level Task Force on Covid-19 Vaccination held its second full meeting today, chaired by Professor Brian MacCraith.
Further expertise has been added to the task force, which now includes senior representatives from across the Department of Health, the Health Service Executive, the Health Products Regulatory Authority, the Office of Government Procurement and the Department of the Taoiseach, as well as expertise in the areas of public health, supply chain logistics, cold chain logistics, and programme management.
A Government statement said the task force was "on track to deliver the national Covid-19 vaccination strategy and implementation plan to Government by 11 December".
Earlier this evening, the Chief Medical Officer Dr Tony Holohan, who is a member of the task force, said the National Public Health Emergency Team looks forward to adding a vaccine to the various public health measures to deal with this virus.
But he said a vaccine will not, on its own, on do away with these measures.