RIO DE JANEIRO, BRAZIL – July began with good news as the experimental vaccine against the novel coronavirus produced by pharmaceutical giant Pfizer in partnership with biotechnology company BioNTech has yielded positive results in limited human trials. The vaccine has encouraged an immune response in healthy patients but has also caused side effects such as fever when administered in higher doses.
The study was randomized and tested on 45 volunteers who were administered three doses of the vaccine or a placebo; of these, 12 were given a ten microgram dose, 12 received 30 micrograms, 12 received a 100 microgram dose, and nine were administered a placebo version of the vaccine.
The highest dose of 100 micrograms caused fever in half of the trial subjects – as a result of the side effect, the group was not administered a second dose.
After the second dose of the vaccine was administered, three weeks after the first dose, 8.3 percent of the subjects in the ten microgram group and 75 percent in the 30 microgram group also developed a fever.
Sleep disorders were another reported symptom. However, the researchers did not consider the side effects to be serious and they did not lead to hospitalizations.
The vaccine was effective in generating antibodies against Covid-19 and some of them neutralized the virus, which could mean that it is able to stop the virus from acting, but whether this higher level of antibodies is effectively able to produce immunity to the disease is not yet known.
Pfizer will conduct further trials soon to establish whether those who were administered the vaccine are 50 percent less vulnerable to the virus.
The news was posted on the Medrxiv website, a leading distributor of scientific breakthroughs that have not yet been peer reviewed. The results are still to be published in a scientific journal.
The companies have not disclosed the differences in the vaccine’s effects by gender, ethnicity or age group. The next trial stages will also focus on the United States. Provided everything goes well, the company expects to produce up to 100 million doses of the vaccine by the end of this year and another 1.2 billion by the end of 2021.
With the positive results, Pfizer saw its shares rise over four percent in the US stock market.
Source: Exame