A CORONAVIRUS vaccine has been developed which prevents more than nine in 10 people from getting Covid-19, according to a preliminary analysis.

Pharmaceutical firm Pfizer has announced interim findings from its study of the jab, which has been tested on 43,500 people in six countries.

Developed in conjunction with BioNTech, the vaccine was more than 90% effective in preventing Covid-19 among those without evidence of prior infection, with no safety concerns were raised.

The companies are aiming to apply for emergency approval to use the vaccine by the end of the month. They hope to supply 50 million doses by the end of this year and around 1.3 billion by the end of 2021.

READ MORE: Pfizer vaccine: How significant is the new Covid-19 announcement?

Around 12 vaccines around the world have reached the final stages of testing, but this is the first to produce any results.

The jab was formulated using an experimental approach, injecting part of the virus's genetic code into patients to to train the immune system.

Two doses, three weeks apart, are required. Developers say people are protected one week after the second dose.

It has been trialled in the US, Germany, Brazil, Argentina, South Africa and Turkey.

Dr Albert Bourla, Pfizer chairman and CEO, said: "Today is a great day for science and humanity. The first set of results from our phase three Covid-19 vaccine trial provides the initial evidence of our vaccine's ability to prevent Covid-19.

"We are reaching this critical milestone in our vaccine development programme at a time when the world needs it most with infection rates setting new records, hospitals nearing over-capacity and economies struggling to reopen.

"With today's news, we are a significant step closer to providing people around the world with a much-needed breakthrough to help bring an end to this global health crisis. We look forward to sharing additional efficacy and safety data generated from thousands of participants in the coming weeks."

First Minister Nicola Sturgeon welcomed the "very positive" news.

She said: "There's a long way to go, of course, but I think this is news that should all give us some hope today."

Following the Pfizer announcement, the FTSE 100 jumped more than 5.5%, adding £82bn to the value of its shares in the market's best day since March.

Study details

The results are based on the first interim analysis of Phase 3 of the study, and evaluated 94 confirmed cases of Covid-19 in trial participants.

The study enrolled 43,538 participants, with 42% having diverse backgrounds, and no serious safety concerns have been observed, the companies report.

They add that safety and additional efficacy data continue to be collected.

The case split between vaccinated individuals and those who received the placebo indicates a vaccine efficacy rate above 90%, at seven days after the second dose.

Researchers say this means that protection is achieved 28 days after the initiation of the vaccination, which consists of two doses.

However, they caution that as the study continues the final vaccine efficacy percentage may vary.