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Biology subjects

Mols, R.

Publications and source records attributed to Mols, R..

2 recordsLinked to original sources

The oral protease inhibitor (PF-07321332) protects Syrian hamsters against infection with SARS-CoV-2 variants of concern

There is an urgent need for potent and selective antivirals against SARS-CoV-2. Pfizer developed PF-07321332 (PF-332), a potent inhibitor of the viral main protease (Mpro, 3CLpro) that can be dosed orally and that is in clinical development. We here report that PF-332 exerts equipotent in vitro activity against the four SARS-CoV-2 variants of concerns (VoC) and that it can completely arrest replication of the alpha variant in primary human airway epithelial cells grown at the air-liquid interface. Treatment of Syrian Golden hamsters with PF-332 (250 mg/kg, twice daily) completely protected the animals against intranasal infection with the beta (B.1.351) and delta (B.1.617.2) SARS-CoV-2 variants. Moreover, treatment of SARS-CoV-2 (B.1.617.2) infected animals with PF-332 completely prevented transmission to untreated co-housed sentinels.

microbiology↗

Nelfinavir markedly improves lung pathology in SARS-CoV-2-infected Syrian hamsters despite a lack of an antiviral effect

In response to the ongoing COVID-19 pandemic, repurposing of drugs for the treatment of SARS-CoV-2 infections is being explored. The HIV protease inhibitor Nelfinavir, widely prescribed in combination with other HIV inhibitors, has been shown to inhibit in vitro SARS-CoV-2 replication. We here report on the effect of Nelfinavir in the Syrian hamster SARS-CoV-2 infection model. Although treatment of infected hamsters with either 15 or 50 mg/kg BID Nelfinavir [for four consecutive days, initiated on the day of infection] does not reduce viral RNA loads nor infectious virus titres in the lungs compared to the vehicle control, the drug reduced virus-induced lung pathology to nearly the baseline scores of healthy animals. A substantial interstitial infiltration of neutrophils is observed in the lungs of treated (both infected and uninfected) animals. The protective effect of Nelfinavir on SARS-CoV-2-induced lung pathology (at doses that are well tolerated and that result in exposures nearing those observed in HIV-infected patients) may lay the foundation for clinical studies with this widely used drug.

microbiology↗