>>13919567Sure, it is defined by the FDA as "investigational" which means "experimental" in FDA-speak.
"Pfizer-BioNTech COVID-19 Vaccine Emergency Use Authorization Review Memorandum
6
1. Executive Summary
The SARS-CoV-2 pandemic presents an extraordinary challenge to global health and, as of
November 30, 2020, has caused more than 60 million cases of COVID-19 and claimed the lives
of 1.5 million people worldwide. In the United States, over 13 million cases have been reported
to the Centers for Disease Control and Prevention (CDC), with over 260,000 deaths. Based on
a declaration by the Secretary of Health and Human Services (HHS) that the COVID-19
pandemic constitutes a public health emergency with a significant potential to affect national
security or the health and security of United States citizens living abroad, FDA may issue an
EUA for a COVID-19 vaccine after determining that certain statutory requirements are met.
On November 20, 2020, the Sponsor (Pfizer, on behalf of Pfizer and BioNTech) submitted an
Emergency Use Authorization (EUA) request to FDA for an investigational COVID-19 vaccine
(BNT162b2) intended to prevent COVID-19 caused by severe acute respiratory syndrome
coronavirus 2 (SARS-CoV-2). The vaccine is based on the SARS-CoV-2 spike glycoprotein (S)
antigen encoded by RNA and formulated in lipid nanoparticles (LNPs)."
>https://www.fda.gov/media/144416/download"An investigational drug can also be called an experimental drug and is being studied to see if your disease or medical condition improves while taking it. "
>https://www.fda.gov/patients/learn-about-expanded-access-and-other-treatment-options/understanding-investigational-drugs 
