The Slatest

Moderna’s COVID Vaccine Is Nearly 95 Percent Effective, Early Data Shows

Folders labeled "Moderna" are seen in front of a person wearing PPE.
Protocol files for Moderna’s COVID-19 vaccines at the Research Centers of America in Hollywood, Florida. Chandan Khanna/Getty Images

The hopes for a viable and widely distributed vaccine to end the coronavirus pandemic grew on Monday. The biotechnology firm Moderna announced that the preliminary analysis of its COVID vaccine trials found it was even more successful than the Pfizer vaccine results announced a week ago.

According to Moderna, the vaccine trials showed a nearly 95 percent efficacy rate—a surprisingly good outcome, given that leading health experts had said they were hoping for something about 75 percent effective and that the Food and Drug Administration had said it was willing to approve a vaccine that was only 50 percent effective. (For perspective, influenza vaccines are around 60 percent effective at their best.) Out of 30,000 patients in the Moderna trial, 95 people fell ill from the virus, only five of whom had received the vaccine rather than the placebo. The 11 people who experienced severe cases of COVID had all received the placebo.  The results came a week after Pfizer announced that preliminary results in its trials indicated that its vaccine, manufactured using a similar experimental method, was more than 90 percent effective.

Moderna reported that there were no severe side effects in its trials, though some people did experience fatigue, headaches, and muscle pain for a couple days. And Moderna’s vaccine appears to have another advantage on the production side: The company has said it can be stored in regular refrigerators and freezers and does not need to be diluted before it is injected. Pfizer’s vaccine needs to be stored at extremely cold temperatures, which many medical offices and pharmacies do not have the equipment to produce.

The next step for both Pfizer and Moderna is to continue their trials until their trial pool hits around 150 cases. They’ll then submit for an emergency authorization from the FDA, which is expected to grant it within just a few weeks. Both Moderna and Pfizer have already begun gearing up to produce massive quantities of the vaccine, and if everything goes well, health care workers and some other high-risk groups might be able to get the vaccine in early 2021 or even late December. The rest of the American public could receive a vaccine by late spring. The availability of two effective vaccines would make the timeline considerably more likely.

The results that have been released  are preliminary and haven’t been peer-reviewed. A number of questions remain unanswered: whether the vaccine would be suitable for people with various other health conditions; whether it would be suitable for the very old and very young; whether the vaccine stops a patient from being contagious or just from falling ill; and, crucially, how long the immunity would last. But public health experts agree that if the world is going to end this pandemic with a vaccine, there needs to be a number of vaccines produced by different companies in different countries in order to meet the demand. There are a good number of vaccines in late-stage trials around the world, but people living in poorer countries that have not already been buying up vaccines may not be able to get any until 2023 or even 2024, according to researchers from Duke University.

In the U.S., though, the infrastructure is already in place to churn out vaccines, and the federal government has committed to buying 100 million doses—enough for 50 million people—each from Moderna and Pfizer, with the option to buy more. It’s not clear how many of the future vaccine doses would be distributed internationally; according to the New York Times, Pfizer has indicated roughly half of its annual production would be distributed in the U.S.

Moderna has said it hopes to produce enough doses by the end of 2020 for 10 million people to be vaccinated. In 2021, it plans to produce at least enough for 250 million people. Pfizer has said that it hopes to have enough for 15 to 20 million people to begin the vaccination process before the end of the year and vaccinate around 750 million in 2021. Both scenarios are dependent on there being no delays in production.

Moderna was part of “Operation Warp Speed” and received $2.5 billion from the U.S. government in order to develop and manufacture the vaccine. Pfizer declined to be a part of the effort and instead signed a contract to sell its vaccine to the U.S. government once it was produced.

The news comes as the U.S. weathers one of its worst periods of the pandemic. In the U.S., more than 246,000 have died from the virus, and cases have surged more than 80 percent in the last two weeks, hitting the Midwest and Southeast particularly hard. As Americans prepare for Thanksgiving next week, every single state is seeing an increase in cases, and while deaths have remained lower than in the spring, case numbers are pushing hospitals to near capacity in many parts of the country. In North Dakota, health care workers who have tested positive have been authorized to continue to work in COVID units.

One of the ugly ironies of this pandemic is that the sky-high COVID rates have meant that Pfizer and Moderna were able to accelerate their vaccine experiments because their volunteer pool was able to hit the threshold number of COVID cases extremely quickly.