We could have 4 COVID-19 vaccines in March, here's how they differ

Virus Outbreak Britain Challenge Trial
Posted at 10:57 AM, Feb 04, 2021

Researchers at a hospital in Cincinnati and around the country are finishing up clinical trials of AstraZeneca’s COVID-19 vaccine candidate, and it could be submitted for emergency use authorization from the FDA by the end of the month.

That would make it one of two vaccines seeking FDA approval in February, and if things go well for both, Americans could have four vaccines available to them in the next several weeks.

“I think that within the next two weeks, we'll probably have four vaccines available in the United States. We'll have the Pfizer, the Moderna, the Janssen (Johnson & Johnson) and the AstraZeneca I think all before February's out,” Dr. Robert Frenck, director of Children’s Vaccine Research Center at Cincinnati’s Children’s Hospital said.

Pfizer and Moderna’s COVID-19 vaccines were given emergency use authorization by the Food and Drug Administration in mid-December, and were rolled out to Americans by the end of the year.

Both of those COVID-19 vaccines work by using messenger RNA, or MRNA, to “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,” the Centers for Disease Control and Prevention states.

MRNA vaccines do not use any live virus, like some vaccines do. However, the MRNA technology requires very cold temperatures for storage and transportation of the vaccine. Pfizer recommends their vaccine be kept at minus 70 C and Moderna recommends minus 20 C.

Both the Pfizer and Moderna vaccine trials reported more than 94% efficacy when patients were given both doses of the two-shot regiment.

The AstraZeneca COVID-19 vaccine has been approved for emergency use in the United Kingdom and European Union. As mentioned above, they are finishing up their Phase 3 trials in America and other countries, and plan to apply to the FDA for emergency use authorization soon.

Their vaccine is showing to be about 76% effective after the first dose, and 82% after the full two doses.

The Johnson & Johnson COVID-19 vaccine, created by their pharmaceutical group called Janssen, finished their Phase 3 clinical trials last month and applied for FDA emergency use authorization Thursday.

They reported72% efficacy for their single-dose vaccine, and 85% efficacy from severe COVID-19 symptoms. This is the only vaccine candidate at this time with a one-shot vaccination.

The Johnson & Johnson and AstraZeneca versions of the vaccine do not require the super cold temperatures that the Moderna and Pfizer vaccine does. Experts say this would mean the Johnson & Johnson and AstraZeneca vaccines could be transported to more rural and outlying areas of the country, and the world, that may not be able to maintain the cold chain requirements.
The two vaccines work differently, they are not MRNA vaccines.

Rather, the Johnson & Johnson and AstraZeneca COVID-19 vaccines use viral vector technologies. That means it uses a modified version of another virus to deliver instructions to the body on how to create antibodies.

“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,” the CDC explains.

That piece of the virus is enough to trigger a response in the body that produces antibodies and to activate other immune cells. Viral vector vaccines have been used since the 1970s.

So far, all four vaccines have shown small levels of side effects, including headaches, arm aches, fatigue and other symptoms that could last a day or two as the body creates antibodies.

Testing is currently underway in the United Kingdom to see if the efficacy of the vaccines are affected if a person were to receive one shot of one brand of vaccine and one shot of another. At this time, the CDC and others urge people to not mix the vaccines between doses; there has not been a lot of study, if any, on this situation yet.