A recent study has shown that both ritonavir-boosted nirmatrelvir, marketed as Paxlovid, and molnupiravir could reduce mortality and hospitalization among patients infected with Omicron variants.
The study was carried out by researchers from the University of North Carolina and the Cleveland Clinic in Ohio, which examined 68,867 patients diagnosed with COVID-19 at the Cleveland Clinic between Apr. 1, 2022, and Feb. 20, 2023.
About 42.7 percent of the patients were aged 65 years and above, 38.9 percent were male, and 74.7 percent were non-Hispanic white. The follow-up period for these patients was 90 days.
“During the study period, the primary circulating strains in the study areas changed from BA.2 to BA.4/BA.5, then to BQ.1/BQ.1.1, and finally to XBB/XBB.1.5,” the report reads.
Of the total patients, 22,594 were administered nirmatrelvir, 5,311 received molnupiravir (under the brand name Lagevrio) treatment, and the remaining 40,962 did not receive any treatment.
It stated that 30 patients who received nirmatrelvir and 27 who received molnupiravir treatment died within 90 days of Omicron infection. There were 588 deaths among patients who did not receive any treatment.
The adjusted hazard ratios of death were 0.16 (95 percent confidence interval) for nirmatrelvir and 0.23 (95 percent confidence interval) for molnupiravir.
Meanwhile, the adjusted hazard ratios for hospitalization or death were 0.63 (95 percent confidence interval) for nirmatrelvir and 0.59 (95 percent confidence interval) for molnupiravir.
The researchers said "these findings suggest that the use of either nirmatrelvir or molnupiravir is associated with reductions in mortality and hospitalization in patients infected with Omicron, regardless of age, race and ethnicity, virus strain, vaccination status, previous infection status, or coexisting conditions."
“Both drugs can, therefore, be used to treat nonhospitalized patients who are at high risk of progressing to severe COVID-19,” they added.
Both drugs were associated with reductions in hospitalization and death caused by the Omicron subvariants BQ.1.1 and XBB.1.5, according to the study.
Pfizer's Paxlovid and Merck's Lagevrio were granted emergency-use authorizations by the U.S. Food and Drug Administration (FDA) in December 2021. Both oral pills have since been used as post-infection treatments for patients experiencing mild-to-moderate COVID symptoms.
In the revised authorizations, the FDA wrote that health professionals may "no longer require positive results of direct SARS-CoV-2 viral testing" before providing patients with the two drugs. Instead, the authorizations now require that adults and kids 12 years of age and older have a "current diagnosis of mild-to-moderate COVID-19."
"We recognize that, in rare instances, individuals with a recent known exposure (e.g. a household contact) who develop signs and symptoms consistent with COVID-19 may be diagnosed by their health care provider as having COVID-19 even if they have a negative direct SARS-CoV-2 test result," the federal agency added.
"In such instances, their health care provider may determine that treatment with authorized therapeutics may be appropriate if the patient reports mild-to-moderate symptoms of COVID-19 and is at high risk for progression to severe COVID-19."
The FDA granted full approval to Pfizer's Paxlovid in May, clearing the way for the drugmaker to sell it at market rates. U.S. officials said they plan to work through much of the Paxlovid inventory purchased from Pfizer, which is available for free at pharmacies around the country, before moving to a normal commercial market.