Misc 16/11/2020

Covid-19: Moderna Vaccine 94.5% effective

The data are provisional and have to be reviewed by specialists

Quim Aranda
3 min
Una representació del prototip de la vacuna de Moderna

LondonAmerican company Moderna has reported that, according to the first data received, its covid-19 vaccine is 94.5% effective. The results, however, are still provisional, and have to be reviewed by other specialists, but coincide largely with those made public by Pfizer last week. In relation to this vaccine, it has some notable advantages in terms of storage, which would make it much easier to distribute.

The two prototypes are based on a new technology, called messenger RNA, in which fragments of the coronavirus genetic material (RNA) are injected, allowing human cells to use them to make viral proteins that could create antibodies. The big difference with the Pfizer candidate is that Moderna's remains stable at 20 degrees below zero for up to six months and could be kept in a standard refrigerator (between 2 and 8 degrees) for up to one month. In contrast, the Pfizer prototype requires an ultra-cool environment, around minus 80 degrees, and can only be kept in a conventional refrigerator for about five days.

To conduct the Phase III clinical trial, Moderna has enrolled more than 30,000 participants in the United States. The objective of the data analysis was to check the number of infections in the group of volunteers who were given a placebo and those who received the prototype of the vaccine. The company says that "as of two weeks after [administration of] the second dose," data from "the interim analysis" of 95 positive cases of covid-19 indicate that "90 were from the placebo group and 5 were from the mRNA-1273 group," meaning the group that received the prototype. The result is "a point estimate of vaccine efficacy of 94.5% (p < 0.0001 )".

The 95 cases analysed include 15 adults over 65 years of age) and 20 participants who identified themselves from various ethnic communities, (12 Hispanic or Latino, 4 black or African American, 3 Asian and 1 multiracial).

As in the case of the Pfizer prototype, Moderna also claims that there have been no problems with vaccine safety. "A review of adverse events indicated that the vaccine was generally well tolerated." Most of the adverse events would have been mild or "moderately severe". Three, with 2% in frequency after the first dose, included pain at the site of inoculation (2.7%) and, after the second, caused fatigue (9.7%), myalgia, muscle pain (8.9%), arthralgia, joint pain, (5.2%), headache (4.5%), redness of skin at the site of injection (2.0%). The episodes reported were of short duration. The data, however, as in Pfizer's case, are subject to changes in the percentages depending on the final analyses.

Similarly to last week, information on the Moderna prototype has once again triggered euphoria in the stock market. At the moment, the IBEX 35 is up 4%.

Based on the provisional safety and efficacy data, Moderna has announced that it intends to file an emergency use authorisation request with the Food and Drug Administration, the U.S. regulator, in the coming weeks, and anticipates that authorisation will be based on monitoring final safety and efficacy data with a median duration of at least 2 months. Moderna, however, also plans to submit applications for authorisations to global regulatory agencies.

One of the big questions still about Moderna's vaccine, as well as Pfizer's, is whether the prototype will stop the infection as effectively as it normally prevents humans from developing symptoms of the disease. The data presented today indicate that this is the case, and especially that it would prevent almost 100 percent of the most serious disorders. But whether the spread of the infection requires a longer period of time - about six months and blood tests to see whether or not those who have received the injection have been infected despite being asymptomatic.

If the vaccine is finally licensed by the various regulatory agencies, Moderna is able to guarantee one billion doses by the end of next year.

Caution among specialists

Peter Openshaw, professor of experimental medicine at Imperial College London, told the British press: "First we heard 90% of Pfizer and BioNTech effectiveness, then the Russians said 92% and now Moderna says 94.5%. The news from Moderna is tremendously exciting and greatly increases optimism that we will have a good selection of vaccines in the coming months".

Asked by ARA, Salvador Macip, a researcher and professor in the department of molecular and cell biology at the University of Leicester, is also moderately optimistic:"This is good news, but now everyone is rushing to publish preliminary results to make themselves look good. So far, the data has not even been published, neither by Pfizer nor by the Russian company, which says it is also over 90% [effective]. We'll have to wait for the studies to be completed in a few months. Then we can really get the champagne out. If anything, it looks like things are going as planned and we'll start in 2021 with more than one approved or ready-made vaccine.

Speaking to the BBC this Monday at noon, Stephen Hoge, chairman of Moderna, admitted they were "very relieved this morning to hear the results". Hoge hopes that by the end of the year they will have been able to distribute up to "20 million vaccines in the United States" and that the European production plant will be able to supply vaccines by early next year.