Final data from a clinical trial of U.S. pharmaceutical giant Pfizer's Corona drug Paxlovid have confirmed the pill's high efficacy. The group said Monday that the antiviral drug reduces the risk of hospitalization or death by 89 percent in high-risk patients. This is true if treatment was started within three days of the onset of disease symptoms.

If treatment started within five days of the onset of symptoms, protection was 88 percent. The analysis of data from the clinical trial of 2246 adults confirms preliminary results on the efficacy of Paxlovid presented by Pfizer in early November.

The preliminary study results showed that the pill was 89 percent effective in preventing hospitalizations or deaths compared with a placebo. The interim results were based on data from about 1200 people, and the final results include another 1000 subjects. None of the study participants who received the Pfizer treatment died - compared with 12 deaths among those taking the placebo.

The company has now also stated that the drug is also likely to be effective against the omicron variant of the coronavirus. This was suggested by in vitro studies.

Pfizer CEO Albert Bourla said the drug could "save the lives of patients around the world". Treatment with Paxlovid could become an important "tool" in the fight against the pandemic - also in view of the spread of virus variants.

Number of hospitalizations reduced with Paxlovid

Initial data from the pharmaceutical company's second clinical trial showed that the treatment reduced hospitalizations by about 70 percent in about 600 adults at normal risk for infection. "We're talking about an incredible number of lives saved and hospitalizations prevented. And, of course, we can dramatically reduce transmission by using this agent quickly after infection," Pfizer research chief Mikael Dolsten said.

The pill is given in combination with an older antiviral drug called ritonavir. The combination treatment, branded Paxlovid, is taken every twelve hours for five days shortly after the onset of symptoms.

The pharmaceutical company, which already manufactures one of the most widely used Corona vaccines in partnership with German company Biontech, has submitted an application to the U.S. Food and Drug Administration for emergency approval of the drug. The EU drug regulator, EMA, is also reviewing Paxlovid.

The drug reduces the ability of the coronavirus to replicate in the body's cells, slowing the progression of the disease Covid-19. Combined with the drug ritonavir, which is already used to treat HIV patients, the new active ingredient will be administered to patients with HIV.

The U.S. pharmaceutical company Merck Sharp & Dohme (MSD) has also developed Molnupiravir, an antiviral drug against the coronavirus. According to the company, however, its efficacy is only 30 percent.

Photo by Towfiqu Barbhuiya