What is the mechanism of action for oseltamivir?

Oseltamivir works as a neuraminidase inhibitor, which is crucial in preventing the release of viral particles from infected cells. Neuraminidase is an enzyme found on the surface of the influenza virus that breaks down sialic acid residues on the host cell surface and viral envelope. By inhibiting this enzyme, oseltamivir prevents the virus from being able to efficiently spread to neighboring cells, thereby reducing the severity and duration of influenza symptoms.

When the neuraminidase enzyme is inhibited, the function of cleaving the bond between the viral hemagglutinin proteins and sialic acid on the host cell surface is compromised. This inhibition results in clumping of viral particles at the surface of the infected cell and limits their ability to infect new cells, effectively controlling the infection.

In contrast, the other mechanisms listed, such as protease inhibitors, reverse transcriptase inhibitors, and DNA polymerase inhibitors, target various aspects of viral replication or assembly common to different viruses, rather than specifically addressing the influenza virus's escape mechanism through neuraminidase inhibition. These agents play significant roles in the treatment of other viral infections, such as HIV or hepatitis, but are not relevant in the case of oseltamivir and influenza