The UK’s Medicines and Healthcare products Regulatory Agency (MHRA) has already approved the Pfizer coronavirus vaccine (BNT162b2), with doses being delivered around that country starting today. On Thursday of this week, the U.S. Food and Drug Administration’s (FDA) Vaccines and Related Biological Products Advisory Committee (VRBPAC) will review the data and vaccination with the Pfizer vaccine could begin in the U.S. as early as Friday.
This report for professionals by the UK’s MHRA gives more insight into what we know so far.
The report has more detail on the seniors than our Friday update and is equally concerning. Keeping in mind that the large second trial only included healthy community-dwelling seniors — not your typical nursing home population — these quotes suggest that the data on safety and efficacy for our frail, elderly is very limited:
Safety: In Study 2, a total of 21,720 participants 16 years of age or older received at least one dose of COVID19 mRNA Vaccine BNT162b and 21,728 participants 16 years of age or older received placebo. Out of these, at the time of the analysis, 19,067 (9531 COVID-19 mRNA Vaccine BNT162b2 and 9536 placebo) were evaluated for safety two months after the second dose of COVID-19 mRNA Vaccine BNT162b2. Demographic characteristics were generally similar with regard to age, gender, race and ethnicity among participants who received COVID-19 mRNA Vaccine and those who received placebo.
Overall, among the participants who received COVID-19 mRNA Vaccine BNT162b2, 51.5% were male and 48.5% were female, 82.1% were White, 9.6% were Black or African American, 26.1% were Hispanic/Latino, 4.3% were Asian and 0.7% were Native American/Alaskan native. The most frequent adverse reactions in participants 16 years of age and older were pain at the injection site (> 80%), fatigue (> 60%), headache (> 50%), myalgia (> 30%), chills (> 30%), arthralgia (> 20%) and pyrexia (> 10%) and were usually mild or moderate in intensity and resolved within a few days after vaccination. If required, symptomatic treatment with analgesic and/or antipyretic medicinal products (e.g. paracetamol-containing products) may be used.
Contrary to press reports, the actual number of subjects randomized and followed up for safety for two months after the second dose was only 19,067 when the UK approved the vaccine, not the full 44,000 that we’ll eventually have data on. The demographics are more varied in the population than in the earlier trial (which is good), but we still do not have a breakdown of the senior safety outcomes since this statement lumps together adverse reactions for all participants 16 and older:
Efficacy: At the time of the analysis of Study 2, information presented is based on participants 16 years and older. Participants had been followed for symptomatic COVID-19 disease for at least 2,214 person-years for the COVID-19 mRNA Vaccine and at least 2,222 person-years in the placebo group.
In this analysis, compared to placebo, efficacy of COVID-19 mRNA Vaccine BNT162b2 from first COVID-19 occurrence from seven days after Dose 2 in participants without evidence of prior infection with SARS-CoV-2 was 95.0% (95% credible interval of 90.3% to 97.6%).
In participants 65 years of age and older and 75 years of age and older without evidence of prior infections with SARS-CoV-2, efficacy of COVID-19 mRNA Vaccine BNT162b2 was 94.7% (two-sided 95% confidence interval of 66.7% to 99.9%) and 100% (two-sided 95% confidence interval of -13.1% to 100.0%) respectively.
This statement sounds great at face value, but the confidence intervals in the older groups render these efficacy rates largely meaningless and suggest that there were few subjects in the older age cohorts. The 100% efficacy in the 75 and up group means that they had no COVID-19 cases in the oldest group that received the vaccine, but this may just reflect that there were so few people that old in the study since the overall cohort only reported 170 cases.
FDA’s VRBPAC needs to look closely at the actual evidence before issuing an emergency use authorization for our seniors.
In the broader picture, this report specifically excludes a recommendation of the Pfizer coronavirus vaccine for children under 16, people running a fever, some people who are immunosuppressed, some people with bleeding disorders, and pregnant or breast-feeding women. There have been no animal studies completed for potential toxicity to reproduction and development.