‘Nothing too surprising there’: Pfizer COVID vaccine ingredients are pretty standard, experts say
Experts say the ingredients in the COVID-19 vaccine developed by Pfizer and German partner BioNTech, which was authorized Friday by the U.S. Food and Drug Administration, looks pretty standard for a vaccine.
In a letter to the FDA, Pfizer listed the ingredients in its vaccine. They can be organized into four basic categories:
30 mcg of a nucleosidemodified messenger RNA (modRNA) encoding the viral spike (S) glycoprotein of SARS-CoV-2.
lipids (0.43 mg (4-hydroxybutyl)azanediyl)bis(hexane-6,1-diyl)bis(2-hexyldecanoate), 0.05 mg 2[(polyethylene glycol)-2000]-N,N-ditetradecylacetamide, 0.09 mg 1,2-distearoyl-sn-glycero-3- phosphocholine, and 0.2 mg cholesterol)
0.01 mg potassium chloride
0.01 mg monobasic potassium phosphate
0.36 mg sodium chloride
0.07 mg dibasic sodium phosphate dihydrate
6 mg sucrose
“Nothing too surprising there,” said Dr. Matthew Heinz, a hospitalist based in Tucson, Arizona. “It’s a normal way of packaging up medications for people.”
The only active ingredient in the vaccine is the messenger RNA encoding the viral spike of SARS-CoV-2. This describes the modified mRNA that contains the code for cells to make the spike protein specific to the virus that will help create antibodies to attack it. The next keyingredient on the list is the lipid molecule, a small ball of fat, that contains four components. Some of the components, like cholesterol, are natural to the body. Other components, like the polyethylene glycol (PEG), are not. PEG is used in a range of pharmaceutical, cosmetic and food products, according to FullFact.org, a registered charity and nonprofit company from England that fact-checks and debunks false or misleading claims.
There have been rare cases of allergic reactions to products with high concentrations of PEG, such as some commonly used laxatives, but the Pfizer vaccine contains a tiny amount of the substance – only enough to maintain the integrity of the lipid molecule.