Rival Merck & Co has asked for emergency use authorisation of its antiviral pill molnupiravir. But that drug reduced hospitalisations and deaths in its clinical trial of high-risk patients by only about 30 percent.
Pfizer shares fell 0.8 percent to $54.75 in trading before the bell, while Merck shares were flat at $72.69.
Dolsten said recent laboratory testing showed that the activity against the protease of the Omicron variant is as “good as basically any SARS-COV-2 variant of concern”.
Ready to ship
The company has said it can have 180,000 treatment courses ready to ship this year and plans to produce at least 80 million more in 2022.
Dolsten said Pfizer is looking to expand that output further as new variants, like the newly-discovered Omicron, could push the need for antivirals substantially higher.
Current vaccines appear to be less effective at preventing infection with Omicron.
Pfizer, which makes one of the leading COVID-19 vaccines with German partner BioNTech, has agreed to allow generic manufacturers to supply versions of the drug to 95 low- and middle-income countries through a licensing agreement with international public health group Medicines Patent Pool (MPP).
However, Dolsten said for next year he expects the drug would be mainly produced by Pfizer.
The US government has already secured 10 million courses of the Pfizer drug for $5.29bn.