Moderna COVID vaccine gets full FDA approval: What to know about vaccine and boosters

The FDA has given a full green light to Moderna's Spikevax vaccine. How will that affect the COVID pandemic?

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Clifford is a managing editor at CNET, where he leads How-To coverage. He spent a handful of years at Peachpit Press, editing books on everything from the first iPhone to Python. He also worked at a handful of now-dead computer magazines, including MacWEEK and MacUser. Unrelated, he roots for the Oakland A's.
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Moderna's Spikevax vaccine was authorized for emergency use in December 2020.

Algi Febri Sugita/Getty Images

The US Food and Drug Administration on Monday announced that it has fully approved the Moderna COVID-19 vaccine -- sometimes known by its brand name Spikevax. The FDA's decision came after studying real-world data from the more than 200 million doses administered in the US since the vaccine received emergency authorization in December 2020.

Acting FDA Commissioner Janet Woodcock declared, "The public can be assured that Spikevax meets the FDA's high standards for safety, effectiveness and manufacturing quality required of any vaccine approved for use in the United States." With today's announcement, the US joins 62 other countries -- including Canada, Japan and Spain -- that have approved Moderna's vaccine.

Woodcock said that the official FDA approval might "instill additional confidence" in Americans who have been hesitant to receive a COVID-19 vaccine. However, experts did not see a large uptick in vaccinations after the full approval of the Pfizer/BioNTech vaccine in August. A Kaiser Family Foundation poll in September found that official FDA approval of Pfizer's vaccine played "a minor role" in decisions to get vaccinated.

In today's press release, Moderna CEO Stéphane Bancel noted: "This is a momentous milestone in Moderna's history as it is our first product to achieve licensure in the US ... We are grateful to the US FDA for their thorough review of our application. We are humbled by the role that Spikevax is playing to help end this pandemic."

The FDA also recently reduced the waiting period from six months to five between the primary series of Moderna's mRNA vaccine and a follow-up booster.

Here's everything you need to know about the Moderna vaccine and booster, including timing, doses, side effects and how to get a free ride to your vaccination appointment. For even more details, here's the latest on COVID-19 vaccines for kids, how you can get a free COVID-19 test kit and what to know about breakthrough infections

Watch this: COVID-19 boosters and the delta variant: What you need to know

Should you wait for an omicron-specific Moderna booster?

The short and simple answer is no. 

Doctors, medical experts and health officials urge everyone to get boosted as soon as they're eligible. Though the omicron variant appears less severe than previous COVID-19 variants, its highly contagious nature and unknown long-term effects mean everyone should get up to date on their COVID vaccines as soon as possible.

There's also no indication on when Moderna's omicron-specific booster will be available and authorized for use. Clinical trials will take at least months to complete, even on a fast-track schedule. In an interview with NBC News on Thursday, Dr. Paul Burton, Moderna's chief medical officer, said the company plans to seek FDA authorization for the omicron-specific booster "by the summer" of 2022.

Several experts question whether the omicron-specific booster will even be needed in the second half of 2022. Development of COVID vaccine boosters specific to the earlier, deadlier delta variant of COVID-19 have mostly been abandoned.

How effective is the Moderna booster against the omicron variant?

Moderna President Stephen Hoge said last months that early results demonstrated the company's COVID-19 vaccine booster increased "omicron-neutralizing antibodies" approximately 37-fold. For comparison, in early December Pfizer said its booster raises antibody levels 25-fold, offering "a sufficient level of protection" against omicron.

Early studies of omicron variant infections in the US support the idea that current vaccines offer weaker protection against the newest strain, especially for individuals who did not get a booster yet. 

According to CDC Director Dr. Rochelle Walensky, of the 43 earliest cases attributed to the omicron variant, 34 patients had been fully vaccinated -- though only 14 had also received a booster. And five of the people who were boosted were infected less than 14 days after the third shot was given, when full protection kicks in.

In January, Moderna CEO Stephane Bancel shared that the company was getting ready to start clinical trials on a COVID vaccine that targeted the omicron variant, with a public rollout expected in the fall. 
"There are discussions ongoing on a daily basis," Bancel told CNBC. "We want to be ready with the best product possible for the fall of '22."

What are the Moderna booster's possible side effects?

Side effects for Moderna's booster shot are similar to those from the two primary doses -- pain or swelling at the injection site, as well as fatigue, muscle pain, headache, fever, chills and nausea. The drugmaker said there is "a remote chance" that its COVID‑19 vaccine could cause a severe allergic reaction.

The good news is, according to the CDC, those who got the Moderna booster dose reported far fewer reactions than they did after the second dose of the vaccine. 

Will we need an annual COVID booster shot?

With vaccines appearing to offer waning protection and the continuing evolution of variants, Hoge said we will most likely need seasonal COVID boosters, much like we do with the flu, at least to protect those at high risk of infection.

The CDC updated its guidance to indicate that, starting in 2022, some immunocompromised people will be able to get a fourth COVID-19 booster shot. Israel, Germany and other nations are researching the efficacy of a fourth shot and Dr. Anthony Fauci, chief medical adviser to the president, said a fourth jab was "conceivable" in the US, too.

Is Moderna working on other COVID boosters?

Hoge said the company's current 50-microgram COVID booster gives "quite respectable" protection but Moderna is continuing to study an omicron-specific vaccine and a multivalent shot that could protect against multiple variants, including the alpha and delta strains. 

The firm also said a 100-microgram version of its current vaccine, Spikevax, appears to raise antibody protection 83-fold. Hoge said Moderna could have new versions of its vaccine ready early in 2022, but is not yet planning to ask the CDC and US Food and Drug Administration to amend its booster authorization for the 100-microgram trial version of Spikevax.

When can I get a COVID-19 vaccine booster shot?

On Friday, the FDA cut the waiting period between the second dose of Moderna's shot and a booster from sixth months down to five, after making a similar recommendation about Pfizer's vaccine on Jan. 4. (Some countries, including Germany and South Korea, have shrunk the waiting time down to three months.) 

Moderna's booster is still only approved for healthy Americans ages 18 and up, but the CDC and other health authorities urge people to get their third shot as soon as they're eligible to keep the immune response against omicron, delta and other coronavirus variants as strong as possible. Just 20 weeks after a second shot, the efficacy of Moderna's vaccine plummets to 10% without a booster.

Last week, the FDA approved giving a booster of Pfizer-BioNTech's vaccine, Comirnaty, to healthy kids as young as 12 and to those 5 and up with compromised immune systems or certain other health conditions.

Last month, President Joe Biden outlined a plan to contact the 64 million people on Medicare and AARP's 38 million members about getting a booster. Nationwide pharmacy chains like Walgreens, CVS and Rite Aid are also contacting customers who got a vaccine at their stores when it's time to schedule a booster.

Can people who are pregnant get a booster shot?

COVID-19 booster recommendations apply to all people 18 years and older, including pregnant women: "People who are pregnant or recently pregnant are more likely to get severely ill with COVID-19 compared with people who are not," the CDC website says.  

While there is no evidence that getting vaccinated decreases fertility in women or men, a recent study linked COVID-19 infection in pregnant women to a higher risk of stillbirth

Is the Moderna booster shot a full third dose of the vaccine?

The Moderna booster is a half dose of the same vaccine used in its first two full shots. The goal is to top up the formula and reinforce the body's immune response against the virus and its variants. While the first two shots of the Moderna vaccine were each 100 micrograms, the booster is a 50-microgram dose.

Moderna said a 100-microgram version of its current vaccine, Spikevax, appears to raise antibody protection 83-fold but it has not asked the CDC or FDA to approve the more potent booster.

Moderna is also working on a combination shot that contains this year's flu vaccine and its COVID-19 booster vaccine, but it's not available right now.


Moderna's booster shot is currently half the size of a full dose.

Sarah Tew/CNET

How do I know which pharmacies have Moderna booster shots available?

Boosters are available at roughly 80,000 locations across the US, including over 40,000 pharmacies. Some 90% of Americans have a vaccine site within five miles of where they live.

free service backed by the CDC sends you information on vaccine sites when you text your ZIP code to this number: 438829. The response will show you COVID-19 vaccine locations in your area, along with the brands they carry for certain age groups, for instance, Moderna 18+. This can save you from having to call around, or show up to an appointment to find that your booster of choice isn't available. The text message also offers a shortcut to make your appointment right from your phone screen. 

In addition, you can check Vaccines.gov to see which vaccines are available where, or call 800-232-0233 for additional vaccine information.

Watch this: What to do if you lose your vaccination card, and how to never lose it again

Who can get a Moderna booster shot right now?

All US adults age 18 and older are eligible to receive COVID-19 booster shots if it's been at least five months since they've received a second dose of either the Moderna or Pfizer vaccine. (Those who received the Johnson & Johnson vaccine are eligible for a booster dose after two months.)

Adults are encouraged to get whatever booster dose is available, even if that means mixing and matching vaccine boosters (more below). The CDC's recommendation of mRNA vaccines -- Moderna or Pfizer -- also applies to booster shots.


Moderna's booster shot is free of charge for all adults.

Sarah Tew/CNET

Is it safe to mix and match vaccine and booster brands?

Yes. The FDA has authorized mixing COVID-19 boosters, which in the US means Moderna and Pfizer. Any adult eligible for a booster can get any of the available brands of coronavirus vaccines. If you initially received Johnson & Johnson and it's been two months or longer since you received the initial dose, you'll be able to get the Moderna or Pfizer booster. If you received Moderna or Pfizer for your first two shots, you could pick any authorized vaccine available to you, if you qualify and it's been six months or longer since your second shot.

In its study, the CDC found 95% of those who got Moderna for the first round of vaccine shots chose Moderna for the booster dose.

Is the Moderna COVID-19 booster shot still free?

All booster shots will be free, regardless of immigration or health insurance status. However, depending on where you get your booster shot -- for example, at a local pharmacy -- you may be asked to provide your insurance card information, including your name, date of birth and membership number. But you will not be charged for your COVID-19 vaccine or booster shot.

How can I get a free ride to get my vaccination booster appointment?

Lyft and Uber are offering free rides for some people who need them. An easy way to access those links for more information is through the text feature above. You can also go to Lyft.com/vax or call Uber at 855-921-0033.

What does the Moderna booster shot do?

As the vaccine's effectiveness decreases over time, a COVID-19 booster shot -- whether from Moderna, Pfizer or Johnson & Johnson -- recharges your body's immune response and guards against a breakthrough infection.

Recent studies of the Pfizer and AstraZeneca vaccines show that their effectiveness can begin to wane after six months. Moderna said early data suggests that those who received the Moderna vaccine in 2020 are showing a higher rate of breakthrough COVID-19 infections than those vaccinated this year, suggesting the need for a booster to maintain high levels of protection.

For more on coronavirus treatments and vaccines, here's what we know about monoclonal antibody treatments, the new federal vaccine mandates and why some people may not want the shot.

The information contained in this article is for educational and informational purposes only and is not intended as health or medical advice. Always consult a physician or other qualified health provider regarding any questions you may have about a medical condition or health objectives.