HOW THE VACCINES STACK UP.
A COVID-19 vaccine produced by Johnson & Johnson — the company best known for producing band aids — is safe and effective, according to a Food and Drug Administration review paving the way for a third U.S. vaccine.
While not quite as effective as existing Pfizer and Moderna vaccines, it has two huge advantages. It’s easy to store and ship. And it works after only one shot.
Here’s what to know about this new vaccine: Q: How effective is it?
A: In U.S. trials, the Johnson & Johnson vaccine provided complete protection against COVID-19 death. It showed 86% efficacy against severe forms of the disease. The overall efficacy rate in the U.S. was 72 % in the United States.
The efficacy rates of Moderna and Pfizer vaccines are higher — both around 95%. But comparing the three vaccines is challenging because of differences in the designs and dosing regimens of the clinical trials, say experts.
Q: Can the new vaccine defend against dangerous variant viruses?
A: There is good news on that front.
The vaccine’s effectiveness was not influenced by the high prevalence of a variant in Brazil. In South Africa, with a different variant virus, the vaccine reduced severe or critical COVID-19 by 81.7% starting 28 days after vaccination. It was 64% effective against more moderate disease. Last week, the South African government switched to J & J’s vaccines, instead of using Novavax or AstraZeneca vaccines.
Because Pfizer and Moderna’s vaccines were tested before the emergence of these troubling new variants, it’s not entirely clear how well they will work.
Q: Is there a plan if it fails to work against a variant?
A: Yes, it can be adjusted, or “boosted.”
It’s relatively easy to modify all three vaccines. With the Pfizer and Moderna vaccines, scientists just synthesize a different strand of messenger RNA, said Georgetown University virologist Angela Rasmussen on the “Track the Vax” podcast. It is a little harder to manufacture a different viral vector vaccine, like J&J’s.
“It may be… that people who got vaccinated initially with Johnson & Johnson might be getting a Pfizer or Moderna booster that addresses the variant,” she said. Q: Are there side effects? A: Side effects seem milder – and there were no reports of anaphylaxis.
All three vaccines have modest side effects, such as pain at the injection site, fatigue, headache, muscle pain, and joint pain. This doesn’t mean they’re unsafe. Rather, it shows that the immune system is kicking into gear.
Unexpected side effects for the J & J vaccine occurred at the same rate overall among volunteers who received vaccine and placebo — about 0.5%. A few rare conditions appeared more common with the vaccine, such as blood clot-related conditions or tinnitus, a ringing in the ears.
Significantly, no one suffered a severe allergic reaction called anaphylaxis, which is seen in Pfizer and Moderna vaccines.
That means that people who get the J&J vaccine might not have to be monitored for 15 minutes after injection – easing and speeding up clinics.
Q: How does it work?
A: The J&J vaccine uses a harmless virus, called an adenovirus, to carry the genetic code.
The Pfizer and Moderna vaccines are made using messenger RNA, or mRNA, a technology that delivers a bit of genetic code to cells.
In all three vaccines, this code acts like a recipe to make a protein, called a spike. Our body sees this spike protein as an invader and triggers the immune system, producing antibodies and T cells.
If the body later encounters the actual COVID-19 pathogen, it is able to respond faster and more effectively, as immune cells and antibodies specific to the virus are produced rapidly in the body to prevent disease.
Q: What is the advantage to J&J’s approach?
A: It makes it a simple onedose shot.
The J&J vaccine is the first vaccine to show efficacy given as a single dose. That’s a huge advantage when it comes to vaccinating as many people as possible, especially in rural areas. It’s also more convenient to ship and store.