Pfizer announced on Monday that early results from clinical trials showed that its coronavirus vaccine was more than 90 percent effective.

In a statement issued on Monday, November 9, Albert Bourla, the chairman and CEO of Pfizer, said: “I am happy to share with you that Pfizer and our collaborator, BioNTech, announced positive efficacy results from our Phase 3, late-stage study of our potential COVID-19 vaccine. 

“The vaccine candidate was found to be more than 90% effective in preventing COVID-19 in participants without evidence of prior SARS-CoV-2 infection in the first interim efficacy analysis.”

"The results demonstrate that our mRNA-based vaccine can help prevent COVID-19 in the majority of people who receive it. This means we are one step closer to potentially providing people around the world with a much-needed breakthrough to help bring an end to this global pandemic.

"This is a first but critical step in our work to deliver a safe and effective vaccine.

"It’s important to note that we cannot apply for FDA Emergency Use Authorization based on these efficacy results alone. More data on safety is also needed, and we are continuing to accumulate that safety data as part of our ongoing clinical study.

The Pfizer Plant in Newbridge County Kildare, which could play a role in the pharmaceutical firm's coronavirus vaccine.

The Pfizer Plant in Newbridge County Kildare, which could play a role in the pharmaceutical firm's coronavirus vaccine.

"We estimate that a median of two months of safety data following the second and final dose of the vaccine candidate - required by FDA’s guidance for potential Emergency Use Authorization – will be available by the third week of November.

"We are also generating data to show that our vaccine can be consistently manufactured to meet quality standards.

"Efficacy, safety, and consistent manufacturing are the three requirements that are needed before we are able to file for authorization."

Separately, in a tweet, Bourla said:

Today is a great day for both science and humanity, as the first set of results from our Phase 3 COVID-19 vaccine trial provides compelling evidence of our vaccine’s ability to help prevent COVID-19.

— AlbertBourla (@AlbertBourla) November 9, 2020

According to The Irish Times, Pfizer's testing results "far exceed the US Food and Drug Administration’s criteria for approving a Covid-19 vaccine, which mandates an efficacy of at least 50 percent in placebo-controlled trials.

No vaccine is 100 percent effective, according to the World Health Organisation.

Dr. Tedros Adhanom Ghebreyesus, the Director-General of the World Health Organization, said on Monday that the WHO welcomes the "encouraging" news:

We welcome the encouraging vaccine news from @pfizer & @BioNTech_Group & salute all scientists & partners around the 🌍 who are developing new safe, efficacious tools to beat #COVID19. The 🌍 is experiencing unprecedented scientific innovation & collaboration to end the pandemic!

— Tedros Adhanom Ghebreyesus (@DrTedros) November 9, 2020

Not long after Pfizer made their announcement on Monday, Ursula von der Leyen, the president of the European Commission, said that the European Commission had contracted Pfizer to provide up to 300 million doses:

Great news from @pfizer & @BioNTech_Group on the successful results of their latest clinical trial for a #COVID19 vaccine. European science works!@EU_Commission to sign contract with them soon for up to 300 million doses.

Let's keep protecting each other in the meantime.

— Ursula von der Leyen (@vonderleyen) November 9, 2020

The news of the advancement was well received in both the Republic of Ireland and Northern Ireland, where, as of Monday afternoon, had reported a combined 2,739 coronavirus-related deaths and 109,047 confirmed cases of coronavirus.

Stephen Donnelly, the Minister of Health in the Republic of Ireland, said in a tweet that it was "positive news:"

Positive news on a potential COVID-19 vaccine. More work to be done, but good reason to be optimistic. A great start to the week!

— Stephen Donnelly (@DonnellyStephen) November 9, 2020

Robin Swann, the Minister for Health in Northern Ireland, said in a statement: "We have been waiting a long time for positive news," but added, "However, I would appeal to everyone not to let down their guard just because there is some light at the end of this very long tunnel."

Arlene Foster, the First Minister of Northern Ireland, said the development was “great news:”

The fight of common humanity against COVID is making significant strides forward. Great news from the vaccine trials. This is much needed hope. Our thanks to all those working on vaccine research.

— Arlene Foster #We’llMeetAgain (@DUPleader) November 9, 2020

Simon Harris, the Minister for Further & Higher Education, Research, Innovation & Science in the Republic of Ireland, said it was "badly needed hope:"

Hope. Badly needed hope...

— Simon Harris TD (@SimonHarrisTD) November 9, 2020

The news comes a week after Pfizer announced a €300 million investment for further development of existing Irish manufacturing sites in Grange Castle in Dublin, Newbridge in Kildare, and Ringaskiddy in Cork. The investment will also create some 300 new jobs in the country. The US pharmaceutical firm has other locations in Ringsend in Dublin, CityWest in Dublin, and Little Island in Cork.

According to The Irish Examiner, the coronavirus vaccine breakthrough is unlikely to involve Cork employees in its production, but Newbridge may have a role down the line.