The two-dose vaccine, developed by US biotech firm Moderna, has been described by health secretary Matt Hancock as “another encouraging step forward” and becomes the second promising candidate after Pfizer’s breakthrough was announced last week.
Supplies of the vaccine are not expected to be widely available until spring of next year, though experts have hailed the emergence of a second coronavirus jab within the space of eight days as another vital development in bringing the pandemic under control.
Britain has secured 5 million doses of a new coronavirus vaccine which early results show is almost 95 per cent effective in preventing symptomatic Covid-19.
According to provisional trial data, the two-dose vaccine has proven to be safe and even more efficacious than its Pfizer rival, which uses the same mRNA technology platform.
Jonathan Van-Tam, England’s deputy chief medical officer, said the results were “brilliant news” and compared Moderna’s announcement to another penalty kick “that’s also gone into the back of the net”.
“So we’re starting to feel in a better position,” he told a Downing Street press conference.
No 10 has now agreed deals for seven different vaccine candidates, and has access to 355 million doses – the majority of which will be provided by AstraZeneca. The government had initially overlooked the Moderna jab before announcing on Monday that a deal had been reached with the American company.
“We have prioritised agreements with developers who offer different kinds of vaccine, can deliver early supplies to the UK and have advanced supply chains in place,” Boris Johnson’s official spokesperson said.
Moderna has said it expects to provide the US government, which helped to fund research into the vaccine, with 20 million doses by the end of the year. It has also reached an agreement with the European Union to provide up to 160 million shots for its member nations.
It is understood that Moderna does not currently have an advanced European supply chain in place, but is currently planning to “scale up” its capacity to deliver to the continent. It is thought the UK’s doses, which will be enough to vaccinate 2.5 million Britons, will not be available before next spring.
Interim data released by Moderna on Monday shows that 95 Covid infections have been recorded from its ongoing phase 3 study, which has enrolled 30,000 volunteers in the US. Covid-19 was observed in 90 volunteers from the placebo group and five participants who had received the vaccine, returning an efficacy rate of 94.5 per cent.
Moderna said it will continue its large-scale trial until 151 cases have been reached, and intends to submit for an Emergency Use Authorisation (EUA) with US regulators “in the coming weeks”.
Stephane Bancel, CEO of Moderna, said the development marked a “pivotal moment”.
“This positive interim analysis from our phase-3 study has given us the first clinical validation that our vaccine can prevent Covid-19 disease, including severe disease,” he said. “This milestone is only possible because of the hard work and sacrifices of so many.”
Moderna, based in Boston, intends to manufacture between 500 million and 1 billion doses globally throughout 2021.
The biotech firm said its candidate, named mRNA-1273, could be stored at fridge temperature for 30 days, or -20C for up to six months.
This will make the vaccine more accessible for the global market, unlike the Pfizer vaccine which needs to be stored and transported at -70C, and can only survive in fridge conditions for five days.
“These factors, while useful in high-income countries, will be of great value in low- and middle-income countries where there is a massive need for a vaccine that is able to be delivered to the population,” said Stephen Evans, a professor of pharmacoepidemiology at the London School of Hygiene & Tropical Medicine.
The Moderna jab uses messenger RNA (mRNA) technology, which relies on synthetically-produced genetic coding to generate an immune response in humans, and is produced at a scale more rapidly than conventional vaccines.
A number of other vaccines that use the same platform are also in development, including the British jab being developed by Imperial College London, sparking hope that these candidates will be equally effective.
Peter Openshaw, professor of experimental medicine at Imperial College London, said: “This is a loud vote of confidence in RNA vaccine technology, which seems to be safe, acceptable and effective in studies of 70,000 people [including both Moderna and Pfizer trials]. These results set a high bar for the other vaccines in the pipeline.”
Unlike Pfizer, Moderna has released a detailed breakdown of its trial data. Of the 95 infections recorded to date, 15 of the participants were aged over 65 while 20 identified as being from diverse communities – two groups that have been identified as at-risk during the pandemic.
Professor Trudie Lang, director of The Global Health Network at the University of Oxford, said: “These early results suggest that there was a representation across different age groups and diverse communities in the protected group.
“This is really encouraging and it further demonstrates that a vaccine for Covid is a real probability and that having more than one supplier should help assure better and more equitable global availability.”
Dr Zoltan Kis, a research associate at Imperial College London’s Future Vaccine Manufacturing Hub, explained that Moderna’s vaccine uses a higher amount of mRNA per dose compared to its Pfizer rival.
This means that Pfizer will be able to manufacture more doses using the same scale of production as Moderna – once the two candidates are approved. However, Dr Kis added, the ability to store mRNA-1273 at higher temperatures will allow doses to “be distributed substantially easier and at lower costs”.
Independent analysis of the Moderna vaccine did not find any significant safety concerns. Adverse reactions to the jab were considered mild or moderate in severity, and included fatigue, pain around the site of injection or headaches.
As with the Pfizer vaccine, it is not currently known if Moderna’s version prevents community transmission of Covid-19. Nor is there any indication of how long immunity lasts among vaccinated individuals.
The European Medicines Agency said separately on Monday that it had begun a rolling review of Moderna’s trial data, while the UK’s Medicines and Healthcare products Regulatory Agency (MHRA) is similarly assessing the vaccine.
Along with the US, Canada and Japan have all placed orders with Moderna for millions of doses each.
Dr Richard Hatchett, CEO of the Coalition for Epidemic Preparedness Innovations (CEPI), said the results for the vaccine were “as good as we could have hoped for and really terrifically encouraging”.
“All in all this is another great day in the struggle against Covid-19,” he added. “We have a long way to go, of course, but we are accumulating the tools we will need to end the pandemic.”