The ongoing Phase 3 clinical trial of Pfizer / BioNTech’s coronavirus vaccine continues with real-world vaccinations and comparative studies. More good news comes for this mRNA technology vaccine: it is confirmed that protection after the second dose lasts at least 6 months and that Pfizer is protective against the most feared variant compared to vaccines, the South African one.
At least six months of protection
The data comes from a declaration by the manufacturer, which, based on these results, is going to ask the US FDA (the agency responsible for drugs) for “full approval” (the “standard” authorization), while vaccinations are now administered under an emergency clearance. It would be the first in the world, just in case. The effectiveness measured in the field reaches the 91% against the disease (any symptoms) for six months. If it seems little it is not, because the previous best estimate offered to date was 90 days. These are controlled studies and not experiences or deductions in the field, so they are reliable and validated results scientifically that vaccinated people can rely on. With regard to the more serious symptoms, the efficacy was equal to 95.3% and with regard to preventing deaths it was 100%.
Full effectiveness against South African
The other encouraging fact is the full effect against the worrying variant B.1.351 of the virus, which is the dominant strain circulating in South Africa and which researchers feared had evolved in such a way as to circumvent vaccine protection because it contains a specific mutation (E484K) which in some in vitro experiments reduced the neutralizing power of antibodies (developed with vaccine or after recovery). In South Africa, 800 participants were enrolled and nine cases of Covid were observed, all in the placebo group, indicating a vaccine efficacy of 100%, the company said. In Italy, the South African variant is widespread at 4% (WHO the Italian data on the variants in circulation). The fact that the vaccine is effective against this variant suggests its effectiveness also with the other two present in Italy, the English and the Brazilian, which against vaccines have so far shown less power to evade the antibody response than the South African. .
Minimal side effects
Also confirmed the data on safety: The most common adverse events were injection site pain, fatigue and headache. The company studied the vaccine in more than 46,000 volunteers with more than 12,000 vaccinated participants having at least six months of follow-up after their second dose. On Wednesday, the two companies released data from a small study of aged volunteers 12 and 15 years which showed, even in this case, 100% effectiveness in that age group.
April 1, 2021 (change April 1, 2021 | 16:26)