Moderna Covid vaccine candidate almost 95% effective, trials show
The race for a coronavirus vaccine has received another shot in the arm with the US biotech firm Moderna becoming the latest to reveal impressive results from phase 3 trials of its jab.
An interim analysis released on Monday, and based on 95 patients with confirmed Covid infections, found the candidate vaccine has an efficacy of 94.5%. The company said it planned to apply to the US regulator, the Food and Drug Administration, for emergency-use authorisation in the coming weeks. In the analysis, 90 of the patients received the placebo with the remaining five the vaccine.
The results are the latest encouraging news to emerge from the breakneck effort to develop a vaccine against coronavirus and follow a similar interim analysis earlier this month from a collaboration between Pfizer and the German firm BioNTech, which suggest its vaccine is 90% effective at preventing illness.
The Moderna vaccine, which is being trialled in more than 30,000 volunteers, is not expected to be available outside the US until next year. The biotech company said it would have 20m doses ready to ship in the US before the end of 2020 and hoped to manufacture 500m to 1bn doses globally next year.
So far, the UK does not stand to benefit from the vaccine but a government spokesman confirmed it was in “advanced discussions” to procure it. Moderna has agreed to provide the US with 100m doses, with an option to buy 400m more. Japan, Canada, Switzerland, Qatar and Israel have also signed agreements, and the European commission has a “potential purchase agreement” for 80m-160m doses. The UK chose not to participate in the EU vaccine purchase scheme, with the health secretary, Matt Hancock, arguing in July that the government could source a vaccine faster on its own.
The Moderna vaccine, which is based on similar mRNA technology as BioNTech’s, is expected to be assessed by the FDA on a final analysis of 151 Covid cases among trial participants who will be followed on average for more than two months.
If the results remain as impressive as the trial goes on, the Moderna vaccine could potentially provide a major advantage over the Pfizer vaccine. While Pfizer’s vaccine requires ultracold freezing between -70C and -80C from production facility to patient, Moderna said it had improved the shelf life and stability of its own vaccine, meaning that it can be stored at standard refrigeration temperatures of 2C to 8C for 30 days. It can be stored for six months at -20C for shipping and long-term storage, the company said.
At £38 to £45 for a course of two shots, Moderna’s vaccine is more expensive than the other frontrunners. AstraZeneca and Oxford University are aiming to sell their vaccine at about £3 a dose, while vaccines in trial with Johnson and Johnson and a collaboration between Sanofi and GSK are both expected to cost about £8 a dose. Pfizer is charging the US about £30 for a two-shot course. The UK has ordered 40m Pfizer shots but none of the Moderna vaccine.
Moderna’s two-shot vaccine injects genetic material called mRNA into the body, which cells then use to churn out the spike protein the virus uses to invade cells. The spike protein covers the surface of the virus and is one of the main targets of the body’s immune response to wipe out the infection.
The interim results are based on an analysis of confirmed Covid cases among both placebo and vaccinated arms of the trial, starting two weeks after the second dose is administered.
Given the relatively small number of cases analysed there is some statistical uncertainty over the 94.5% figure. But Stephen Evans, professor of pharmacoepidemiology at the London School of Hygiene and Tropical Medicine, said that based on the numbers released, the efficacy was still likely to be better than 85%.
A question mark that remains over the Pfizer vaccine is whether it prevents serious illness. The Moderna results, released by an independent data safety monitoring board, are encouraging on this point. Of 11 participants who developed severe Covid while on the trial, all were in the placebo group. The results also suggest the vaccine is effective in older people and those from diverse ethnic backgrounds.
Moderna’s interim analysis includes a safety review of data available so far. The company said it had found no significant safety concerns, with most reactions being mild to moderate and short-lived. Among the side effects reported were injection site pain in 2.7% of trial volunteers after the first jab. After the second, the most significant side effects included fatigue in 9.7%, muscle pain in 9% and joint pain in 5%. Others had headaches, other pains, or redness at the injection site.
Prof Trudie Lang, professor of global health research at the University of Oxford, said: “It is very good news indeed to see another vaccine coming through with similar efficacy results as were reported last week from Pfizer.
“This is also an interim analysis, which means that there were enough cases within the vaccinated volunteers to give statistical significance and allow the team to break the blind to determine who had the active vaccine and who had placebo.
“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.”
Peter Openshaw, professor of experimental medicine at Imperial College, London, said the Moderna results were “tremendously exciting” and boosted optimism that a choice of good Covid vaccines would be available in the next few months.
He said the inclusion of high-risk and elderly people in the Moderna trial suggested the vaccine would protect those most vulnerable to the disease, while the reported side effects were “what we would expect with a vaccine that is working and inducing a good immune response”.
“Moderna have also announced that the vaccine can be kept in a conventional freezer at -20C for up to 6 months, and that once thawed the vaccine can be kept for up to 30 days at standard refrigerator temperatures of 2 to 8C. This makes the vaccine much easier to deliver,” he said.
“This announcement adds to the general feeling of optimism about vaccines for Covid-19. What we still don’t know is how long any protective immunity may last. For that, we will need to wait,” he added.
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