Pfizer Says Final Stage Trials Prove Vaccine's Efficacy Even After Six Months

Pfizer Inc has said the Covid-19 vaccine it developed with BioNTech SE has proved to be highly effective against the disease even after six months. Based on the newly ratified long-term results Pfizer will seek an expansion of the vaccine's regulatory status.

Pfizer said the latest trial was conducted on 46,307 people. The 'final stage' trial confirmed that the vaccine had an efficacy rate of 91.3 percent in preventing symptomatic Covid-19 even after six months. The protection starts one week after the second dose. Within the US, the efficacy rate is even higher at 92.6 percent, Pfizer said.

pfizer-biontech vaccine
A lab study has suggested that the South African variant may reduce antibody protection from the Pfizer Inc/BioNTech vaccine by two-thirds. Pixabay

Pfizer said no new serious safety concerns were identified during the final trial.

However, the company had originally said that the efficacy rate would be 95 percent, based on short-term results.

Neutralizes Brazil Variant

The latest finding was released in a joint statement by both the companies. It has not been independently assessed in peer reviews or published in scientific journals.

It was earlier reported that the coronavirus vaccine by Pfizer Inc and BioNTech SE was able to neutralize the Brazil variant of the virus, which has been spreading rapidly in the last few months.

The blood of people who had been administered with the Pfizer vaccine was found to have neutralized an engineered version of the virus, according to a laboratory study published in the New England Journal of Medicine. Pfizer had earlier said that the vaccine neutralized other contagious coronavirus variants identified in the UK and South Africa.

Earlier this week it was revealed that Pfizer and Moderna vaccine were judged as highly effective against Covid-19 even after a single shot. These vaccines reduce the risk of infection by as much as 80 percent at least two weeks after the first of two shots, a study using real-world data in the US showed.

Another Breakthrough

The risk of infection fell 90% by two weeks after the second shot, the study of nearly 4,000 US healthcare personnel and first responders found.

In yet another breakthrough, BioNTech and Pfizer said the vaccine showed 100 percent efficacy in the 12-15 age group. The companies said they are looking for approval for the vaccine use in the crucial age group as the trials showed that the vaccine generated robust antibody response among the teenagers.