Question:

I've heard that the U.S. Food and Drug Administration (FDA) said Pfizer's Comirnaty and BioNTech formulas are distinctly different in their vaccine approval letter. Is that true?

Answer from infectious diseases pharmacist Bryan Alexander, PharmD:

No. In terms of what is contained inside the vial of each they are identical. Pfizer and BioNTech simply formally "branded" or named their vaccine Comirnaty. 

BioNTech is the German biotechnology company that partnered with Pfizer in bringing this COVID-19 vaccine to market. 

"Pfizer Comirnaty" and "Pfizer BioNTech COVID-19 vaccine" are biologically and chemically the same thing.

The confusion stems from this section of the FDA's Comirnaty Vaccine Information for Recipients and Caregivers sheet: 

"[1] The licensed vaccine has the same formulation as the EUA-authorized vaccine and the products can be used interchangeably to provide the vaccination series without presenting any safety or effectiveness concerns. The products are legally distinct with certain differences that do not impact safety or effectiveness."

The FDA desires to have a single, combined Vaccine Information Sheet. A single sheet keeps things simple for the people administering and receiving the vaccines. Since the branded and unbranded vials of vaccines are chemically identical, despite being legally distinct, this information must be included.

The FDA's approval letter outlines rules Pfizer and BioNTech must follow to maintain full approval for people ages 16 and older. It also explains how the companies can earn full FDA approval for people 16 and under. 

These rules include completing a series of studies focusing on people under age 16 to obtain full approval in this population. These studies are already underway. The companies must also maintain post-approval studies for those over 16 to monitor the vaccine's safety and efficacy. 

These studies are a standard part of the post-approval process that most drugs must go through to maintain full FDA approval. This list of required studies does not mean the vaccine is not fully approved. 

Why is the name just showing up now?

Medications often have a scientific name or number throughout the research and development process and are given a brand name upon FDA approval.

In a joint media statement released by Pfizer and BioNTech on Dec. 21, 2020, the companies explained, "The vaccine will be marketed in the EU under the brand name COMIRNATY, which represents a combination of the terms COVID-19, mRNA, community and immunity, to highlight the first authorization of a messenger RNA (mRNA) vaccine…"

Pfizer and BioNTech received permission to market the vaccine as Comirnaty in the United States within the FDA's recent approval. The FDA's approval letter states, "You may label your product with the proprietary name, Comirnaty, and market it in 2.0 mL glass vials, in packages of 25 and 195 vials."

Comirnaty, also commonly referred to as the Pfizer COVID-19 vaccine, received final FDA approval for people age 16 and older on Aug. 23.