Oseltamivir (Tamiflu) treats influenza by which mechanism?

• A Inhibition of viral RNA polymerase (PB1 subunit)
• B Competitive binding to the hemagglutinin receptor, preventing viral entry
• C Inhibition of M2 ion channel, preventing viral uncoating
• D Inhibition of neuraminidase (sialidase), preventing release and spread of new influenza virions from infected cells ✓

Explanation

Neuraminidase cleaves sialic acid residues on host cell surfaces and on newly synthesized viral particles, allowing their release and spread to uninfected cells. Oseltamivir and zanamivir are competitive inhibitors of neuraminidase. Without functional neuraminidase, new virions remain clumped on the surface of infected cells and are prevented from spreading. Amantadine/rimantadine block the M2 ion channel (only active against influenza A). Baloxavir marboxil inhibits the cap-dependent endonuclease of the viral polymerase.

Reference: KD Tripathi, Essentials of Medical Pharmacology, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.