Category: catabolism
Two non-polymerase viral targets with FDA-approved drugs. Influenza neuraminidase cleaves sialic acid linkages → releases progeny virions from infected cell surface; oseltamivir + zanamivir mimic the sialic-acid transition state → competitive inhibition. Effective if started within 48h of symptom onset; modest symptom-duration reduction (~1 day) + reduction in lower-respiratory complications. Baloxavir targets the influenza polymerase PA cap-dependent endonuclease — single-dose oral therapy (a different mechanism from the neuraminidase inhibitors). SARS-CoV-2 main protease (Mpro / nsp5) cleaves the polyprotein; nirmatrelvir is a covalent peptidomimetic Mpro inhibitor (always boosted with ritonavir as Paxlovid to inhibit CYP3A4 clearance of nirmatrelvir).