Healthcare professionals and residents of long-term care facilities will be the first to receive doses of Pfizer’s COVID-19 vaccine, providing a glimmer of hope for the year 2020.
It’s completely normal to have concerns about a new vaccine, even if you’re eager to get immunized and help stop the global pandemic. For example, how will the vaccines be distributed?
There are currently two vaccines available, but more are being developed. Both Pfizer and Moderna have made their ingredients accessible to the general public, with Pfizer having recently received an Emergency Use Authorization (EUA) from the Food and Drug Administration (FDA) and Moderna still awaiting one.
How do the COVID-19 vaccines work?
The messenger RNA (mRNA) technology is used in both the Pfizer and Moderna vaccines. According to the Centers for Disease Control and Prevention, mRNA has been studied for more than ten years even though these vaccines are the first of their kind. Before it was improved and re-targeted for COVID-19, it was developed years ago to try to treat other diseases but it never advanced past early-stage clinical trials.
According to the CDC, the coronavirus mRNA vaccines do not contain live or inactivated virus; instead, they function by encoding a portion of the spike protein present on the surface of SARS-CoV-2, a novel coronavirus that is the source of COVID-19. (This is the portion of the virus that gives it its distinctive shape of a crown.)
A portion of the encoded SARs-CoV-2 protein is used in vaccines to stimulate your body’s immune system. How? Your cells are instructed by the mRNA to create a protein that resembles the spike protein of the coronavirus, fooling your body into believing it needs to fight an infection. (Remember: It’s just a small portion of the protein and poses no health risks.)
Because the new proteins are perceived as foreign invaders, your body mounts a defence against them, creating antibodies that are particular to SARs-CoV-2 in the process. It is not yet known for how long these COVID-19 infection-fighting cells remain in your body to aid your body in combating subsequent infections with the virus. The proteins and mRNA will eventually be eliminated by your body on its own as it goes about its business.
What are the Pfizer COVID-19 vaccine ingredients?
The ingredients list and other safety information for the Pfizer COVID-19 vaccine were made available online when the FDA granted it an EUA. The list consists of:
- mRNA
- Lipids ((4-hydroxybutyl)azanediyl)bis(hexane-6,1-diyl)bis(2-hexyldecanoate), 2 [(polyethylene glycol)-2000]-N,N-ditetradecylacetamide, 1,2-Distearoyl-sn-glycero-3- phosphocholine, and cholesterol)
- Potassium chloride
- Monobasic potassium phosphate
- Sodium chloride
- Dibasic sodium phosphate dehydrate
- Sucrose
What components make up the Moderna COVID-19 vaccine?
Although the FDA has not yet granted Moderna an EUA, this is anticipated to happen very soon. Additionally, Moderna recently made its FDA ingredients list available:
- mRNA
- Lipids (SM-102, 1,2-dimyristoyl-rac-glycero3-methoxypolyethylene glycol-2000 [PEG2000-DMG], cholesterol, and 1,2-distearoyl-snglycero-3-phosphocholine [DSPC]),
- Tromethamine,
- Tromethamine hydrochloride
- Acetic acid
- Sodium acetate
- Sucrose
What function do the COVID-19 vaccine’s components serve?
Jamie Alan, Pharm.D., Ph.D., assistant professor of pharmacology and toxicology at Michigan State University, explains that these components cooperate and ensure that you receive a stable, effective vaccine. Although each vaccine has slightly different ingredients, they all work toward the same end, according to her.
The driving force behind both vaccines is their mRNA. But fats called lipids also play a significant role. According to infectious disease specialist Amesh A. Adalja, M.D., senior scholar at the Johns Hopkins Center for Health Security, these “facilitate delivery of the mRNA to cells.” Until it is time to inject the mRNA into your body, these fats enclose and shield it.
Everything else, according to Alan, contributes to preserving the pH or stability of the vaccine, including potassium choloride, sucrose (sugar), and acetic acid. According to the CDC, this is essential to maintaining the vaccine’s efficacy after it has been produced.
Vinegar, for instance, contains acetic acid. Alan adds, “Sodium acetate is also a stabilizer. It can be found in a variety of foods and is also useful in IV fluids as an electrolyte.
The COVID-19 vaccines have similar formulas, and the ingredients don’t surprise experts.
According to Alan, the slight difference might help to explain why each requires a different amount of storage. It will be challenging to comply with the Pfizer vaccine’s requirement to maintain it at a freezing -70 degrees Celsius as distribution expands in 2021. The Moderna vaccine can, however, be delivered at -20 degrees Celsius and, after that, can be safely kept in refrigerators for up to 30 days.
According to Dr. Adalja, the common person won’t have access to either of the two-dose vaccines until the late spring or early summer. Once it is available to you, it’s crucial to keep in mind that any vaccine approved by the FDA is secure—and moves us one step closer to jointly ending the COVID-19 pandemic.