Data from an ongoing Phase 1/2 clinical trial evaluating three dose levels of Pfizer (NYSE:PFE) and collaboration partner BioNTech SE’s (NASDAQ:BNTX) COVID-19 vaccine candidate BNT162b1 in healthy volunteers showed an acceptable safety profile and dose-dependent increases in glycoprotein receptor-binding domain (RBD)-binding IgG concentrations and SARS-CoV-2 neutralizing antibody titers. The data, just published in the journal Nature, was generated on the first two dose levels, 10 µg and 30 µg. The highest dose of 100 µg was only administered once due to increased reactogenicity and the absence of a significant incremental immunogenicity effect compared to the 30 µg dose.
1.6-fold to 4.6-fold increases on geometric mean neutralizing antibody titers after the second dose were observed.
The companies first reported preliminary data from the trial on July 1. The highest neutralizing titers reported then were 1.8x (10 µg) and 2.8x (30 µg).
Premarket: PFE up a fraction, BNTX up 4%.