Pfizer Inc. is resisting requests for study supplies of its Covid-19 pill, Paxlovid, disappointing researchers who say combining the $22 billion therapy with other drugs might stave off resistance.
Pfizer hasn’t started any combination trials in people, and a review of the clinicaltrials.gov database shows no outpatient studies combining Paxlovid, the mainstay US Covid therapy, with other antiviral drugs or antibodies. Some academic researchers and advocacy groups say they can’t get Paxlovid for human studies that could maintain or improve its effectiveness and expand use.