Pfizer’s COVID-19 Vaccine

Pfizer and BioNTech have a COVID-19 mRNA (messenger RNA) Vaccine candidate in a phase 3 trial.

Pfizer will have up to 30,000 participants in phase 3 clinical trial that started in July 2020. As of Aug 20, 2020 they had enrolled more than 11,000 participants.

BNT162b2 remains under clinical study and is not currently approved for distribution anywhere in the world. Assuming clinical success, Pfizer and BioNTech are on track to seek regulatory review for BNT162b2 as early as October 2020 and, if regulatory authorization or approval is obtained, currently plan to supply up to 100 million doses worldwide by the end of 2020 and approximately 1.3 billion doses by the end of 2021. Those interested in learning more about the study can visit using the number NCT04368728.

Systemic events after administration of BNT162b2 were milder than those with BNT162b1. Overall, after Dose 1, systemic events reported by participants 65 to 85 years old who received BNT162b2 were similar to those reported by those who received placebo. After Dose 2 of 30μg BNT162b2, only 17% of participants 18 to 55 years old and 8% of participants 65 to 85 years old reported fever (≥38.0 to 38.9 °C), compared to 75% of 18 to 55-year-old participants and 33% of 65 to 85-year-old participants administered a second dose of 30μg of BNT162b1. Severe systemic events (fatigue, headache, chills, muscle pain, and joint pain) were reported in small numbers of younger BNT162b2 recipients and were transient and manageable. No severe systemic events were reported by older BNT162b2 recipients. There were no reports of Grade 4 systemic events by any BNT162 recipient.

The two-dose 30 μg level of the BNT162b2 vaccine was selected as the candidate vaccine. Seven days after vaccination, the SARS-CoV-2-neutralizing GMTs (immune response) 3.8 times higher among adults 18-55 than convalescent serum (getting antibodies from someone who fought off the disease) from a panel of 38 convalescing COVID-19 patients. For older adults, neutralizing GMTs were 1.6 times higher than the panel.

Moderna also has an mRNA vaccine candidate in phase 3 clinical trials. Moderna and Pfizer are both very close in the timing of their clinical testing.

Phase 3 Clinical testing in the US also has begun for UK based AstraZeneca’s COVID-19 Vaccine candidate AZD1222.

SOURCES – Pfizer, MedpageToday
Written By Brian Wang,