Moderna, Pfizer, J&J vaccines: Similarities and differences

A third COVID-19 vaccine approval means additional options for providers

Moderna, Pfizer, J&J vaccines: Similarities and differences

The COVID-19 Pfizer-BioNTech and Moderna vaccines that hit the region first now have company from a third: Janssen (Johnson & Johnson).

The vaccines are not exactly the same but they accomplish the same things, health officials say. The main difference is that Pfizer-BioNTech and Moderna vaccines require two shots, while Janssen (J&J) requires only one.

The steps toward FDA approval and distribution are the same for all COVID-19 vaccines now in use in the Sanford Health system.

“We are ready to handle either vaccine at any of our locations,” said Jesse Breidenbach, Sanford Health senior executive director of pharmacy, when Moderna’s vaccine came out. “We are ready for fluctuations in supply of either from either manufacturer. By doing it this way, we can vaccinate patients based on what’s available, not just based on how and where we can handle either vaccine.”

It’s good to have different types of vaccines available for use, especially ones with different storage and handling requirements and dosing recommendations. They can offer more options and flexibility for local vaccine providers.

Keep in mind:

  • All COVID-19 vaccines available at Sanford Health have been proven effective at preventing serious illness, hospitalization, and death from COVID-19.
  • You should get the vaccine regardless of which one is made available to you.
  • Even if you’re not a Sanford patient, you can schedule a COVID-19 vaccine appointment.

How they’re made

The Pfizer and Moderna vaccines use messenger RNA to trigger an immune response.

mRNA vaccines are a new type of vaccine to protect against infectious diseases, says the CDC: “To trigger an immune response, many vaccines put a weakened or inactivated germ into our bodies. Not mRNA vaccines. Instead, they teach our cells how to make a protein — or even just a piece of a protein — that triggers an immune response inside our bodies. That immune response, which produces antibodies, is what protects us from getting infected if the real virus enters our bodies.”

Meanwhile, Janssen (J&J) and a few others in clinical trials use viral vectors to trigger immunity.

According to the CDC, “Viral vector vaccines use a modified version of a different virus (the vector) to deliver important instructions to our cells. For COVID-19 viral vector vaccines, the vector (not the virus that causes COVID-19, but a different, harmless virus) will enter a cell in our body and then use the cell’s machinery to produce a harmless piece of the virus that causes COVID-19. This piece is known as a spike protein and it is only found on the surface of the virus that causes COVID-19.”

How they’re stored

Another difference is the storage requirements. The Pfizer vaccine requires ultracold storage (-76 to -112 degrees F), while the Moderna vaccine can be stored at -20 degrees F, or normal freezer temperatures.

The Janssen (J&J) vaccine can be stored at refrigerator temperatures.

“The storage system is much simpler,” Breidenbach said. “We will still be tracking the temperature of both, however, through the entire life of the vaccine until it reaches the patient.”

All three work

Health officials are not picking favorites on which vaccine to take. Availability should be the ultimate determining factor, Breidenbach said.

“The efficacy is similar, and from what we know now, the minimal side-effect profile is similar,” he said.

The vaccines share another key factor: You have to get the shots for them to work.

“Obviously everyone needs to stay vigilant with social distancing, masking and hand hygiene as we move into what we hope is the final stage in our battle against COVID-19,” Breidenbach said. “But the vaccines won’t work unless we use them. We need a good rate of acceptance.”

Information in this story was accurate when it was posted. As the COVID-19 pandemic changes, scientific understanding and guidelines may have changed since the original publication date.

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Posted In COVID-19, Frequently Asked Questions, Immunizations