Pfizer now says its vaccine is 95% effective

LondonThe race for the Covid-19 vaccine has gone wild. The pharmaceutical giant Pfizer, which last week announced that its prototype was 90% effective, has claimed on Wednesday that it is 95% effective and has no serious side effects, after analyzing the first full set of results. The company's new and surprising announcement - which has not yet been validated by any independent scientific committee - comes two days after Moderna Biotechnology assured that its candidate had an efficacy - according to the first analyses, which are still provisional - of 94.5%.

The North American multinational, which has worked in collaboration with the German biotech company BioNTech, reports that "in the next few days" it will request emergency authorization from the Food and Drug Administration, the U.S. regulator, to begin using the vaccine. In the next few days, the same procedures will be carried out with the rest of the world's regulators, after sending the data on safety and efficacy. Regarding the safety of the vaccine, only mild problems of fatigue and headache have been identified.

The hopeful conclusion came after the final efficacy analysis had been carried out, according to which it "met all the main efficacy criteria of the study". Thus, the efficacy rate of the vaccine seems to be 95% "in participants without a previous infection" and also in volunteers with a previous infection, in each case measured 7 days after the second dose. The Pfizer vaccine must be administered in two doses, three weeks apart, which implies a very high degree of immunity 28 days after the first inoculation.

The data is based on the registration of 170 cases of Covid-19, as specified in the study protocol. Of these 170, 162 infections were detected in the placebo group. Only 8 occurred in the control group that received the prototype. "Efficacy was consistent across age demographics, gender, race and ethnicity", states the information provided by the pharmaceutical company. Another fact which would be extremely positive is that "the effectiveness observed in adults over 65 years of age was of over 94%". As for serious cases of infection, nine occurred among the volunteers who received the placebo, and one among those who received the prototype.