Pfizer said Tuesday the final analysis of its Covid-19 antiviral pill still shows nearly 90% effectiveness in preventing hospitalizations and death in high-risk patients, and recent laboratory data suggests the drug is showing its effectiveness against those quickly spreading Omicron variant of the coronavirus retains.
The US drugmaker said last month that the oral drug was about 89% effective in preventing hospital admissions or deaths compared to placebo, based on interim results in about 1,200 people. The data released on Tuesday includes an additional 1,000 people.
Nobody in the study who received Pfizer treatment died, compared with 12 deaths in placebo recipients.
The Pfizer tablets are taken with the older antiviral ritonavir every 12 hours for five days, starting shortly after the onset of symptoms. If authorized, the treatment is sold as a paxlovid.
Pfizer also released early data from a second clinical study showing that the treatment reduced hospital admissions by about 70% in about 600 standard-risk adults.
“That is an impressive result,” said Mikael Dolsten, Pfizer’s Chief Scientific Officer, in an interview.
“We’re talking about an incredible number of lives saved and hospital stays prevented. And if you use this soon after the infection, we will likely drastically reduce the transmission, ”said Dolsten.
Dolsten said he expects approval for use in high-risk individuals from the U.S. Food and Drug Administration and other regulatory agencies shortly. He doesn’t think an FDA advisory panel meeting will be needed.
“We are in very advanced regulatory dialogues with both Europe and the UK, and we have dialogues with most of the major regulators around the world,” said Dolsten.
No oral antiviral treatments are currently approved for Covid in the United States.
Rival Merck has filed for approval of its emergency antiviral pill molnupiravir. But this drug reduced hospital stays and deaths by only about 30% in its clinical trial of high-risk patients.
Some scientists have also raised safety concerns about possible birth defects from the Merck drug, as well as concerns that it could mutate the virus.
Pfizer’s drug works differently. It belongs to a class of drugs called protease inhibitors that are currently used to treat HIV, hepatitis C, and other viruses.
Dolsten said recent laboratory tests showed that activity against the Omicron variant protease is as good as “basically any variant of SARS-COV-2 of concern”.
The company has announced that it will have 180,000 treatment courses available for delivery this year and plans to produce at least 80 million more in 2022.
Dolsten said Pfizer plans to expand this production further as new varieties, such as the newly discovered Omicron, could significantly increase the need for antivirals. Current vaccines appear to be less effective at preventing Omicron infection.
Pfizer, which manufactures one of the leading Covid-19 vaccines with German partner BioNTech, has agreed to enable generic drug manufacturers to deliver versions of the drug to 95 low and middle income countries under a licensing agreement with the international healthcare group Medicines Patent Pool ( MPP). However, Dolsten said he expects the drug to be manufactured primarily by Pfizer over the next year.
The US government has already secured 10 million courses for the drug Pfizer for 5.29 billion US dollars.
