Pfizer, Inc. of New York and BioNTech SE of Mainz, Germany have announced that human clinical trials for an experimental COVID-19 vaccine they have co-developed, known as BNT162, have begun in the United States.1
As part of a global clinical development program, the first human subjects in the U.S. Phase I and Phase clinical II trials of BNT162 received doses of the experimental vaccine at New York University’s Robert I. Grossman School of Medicine in New York City and University of Maryland’s School of Medicine in Baltimore, Maryland.2
In late April 2020, the two companies launched the first human clinical trials of BNT162 in Germany with the goal of testing 200 healthy volunteers between the ages of 18 and 55 years.3
According to Albert Bourla, CEO of Pfizer, “The short, less than four-month time frame in which we’ve been able to move from preclinical studies to human testing, is extraordinary.”1
Clinical Trial Tests Four Variations of BNT162 Vaccine
Phase 1 and Phase 2 clinical trials are designed to be randomized, placebo-controlled, observer-blind, dose-determining and vaccine candidate-selection studies in healthy adults.4 These trials are expected to evaluate the safety, tolerability, immunogenicity and potential efficacy of four different SARS-CoV-2 messenger RNA vaccine candidates using a two-dose or single-dose schedule, at up to three different dose levels and in three age groups (18 to 55 years old, 65 to 85 years old and 18 to 85 years old).4
Each trial participant will receive one of four vaccine candidates—BNT162a1, BNT162b1, BNT162b2, BNT162c2 or a placebo.4 Each vaccine candidate represents a different mRNA format and target antigen.3 Two of the four vaccine candidates are nucleoside modified mRNA (modRNA) vaccines, a third is a uridine containing mRNA (uRNA), and the fourth vaccine candidate uses self-amplifying mRNA (saRNA).3 Each mRNA format is combined with a lipid nanoparticle (LNP) formulation.3
Expanding Human Trials to Thousands of People
Bourla said that if one or two variations of the candidate vaccine appear successful, the companies plan on expanding human trials to a large-scale study with thousands of participants by September 2020.5 He stated:
If things go well, and we feel that the product is safe and efficacious, and the FDA [Food and Drug Administration] and EMA [European Medicines Agency] and other regulatory agencies feel the same, we will be able to deliver millions of doses in the October time frame.5
Pfizer and BioNTech are racing against two other biotechnology companies, CureVac and Moderna, which are also in the clinical trial stage of developing a COVID-19 vaccine using messenger RNA technology.6
mRNA Vaccines May Come with Serious Side Effects
Messenger RNA (mRNA) vaccines, which have never been licensed for use in humans, inject cells with mRNA, usually within lipid nanoparticles, to stimulate cells in the body to become manufacturers of viral proteins.7 According to researchers at University of Pennsylvania and Duke University, mRNA vaccines have potential safety issues, including local and systemic inflammation and stimulation of auto-reactive antibodies and autoimmunity, as well as development of edema (swelling) and blood clots.8
1 Lovelace B. Pfizer begins human testing for experimental coronavirus vaccine in the US. CNBC May 5, 2020.
2 Dearment A. Pfizer, BioNTech dose first U.S. patients in Covid-19 vaccine trial. MedCityNews.com May 5, 2020.
3 Genetic Engineering & Biotechnology News. U.K. Starts Oxford Coronavirus Vaccine Trial as Germany Green-Lights BioNTech and Pfizer. Apr. 23, 2020.
4 U.S National Library of Medicine. Study to Describe the Safety, Tolerability, Immunogenicity, and Potential Efficacy of RNA Vaccine Candidates Against COVID-19 in Healthy Adults. ClinicalTrials.gov May 14, 2020.
5 Bursztynsky J. Pfizer wants to expand human trials of coronavirus vaccine to thousands of people by September, CEO says. CNBC May 12, 2020.
6 Adams B. Pfizer, BioNTech to ramp up COVID-19 vaccine tests, plot major trial boost in fall. FierceBioTech.com May 13, 2020.
7 Horizon Magazine. Five things you need to know about mRNA vaccines. Apr. 1, 2020.
8 Pardi N, Hogan MJ, et al. mRNA vaccines – a new era in vaccinology. Nature Reviews Drug Discovery 2018; 17: 261-279.