Sidebar: Why combine w/ ritonavir esp since lopinavir/ritonavir wasn't effective against COVID19?

They added Ritonavir not for anti-viral effects but to "boost" drug levels of PF-07321332 by inhibiting CYP3A. We do something analogous w/ "ritonavir boosted darunavir" in HIV.
7/

— Nick Mark MD (@nickmmark) November 5, 2021