Medicinal Chemistry

9.3.3 Antivirals Targeting Other Mechanisms

Amantadine (9.1, 1-aminoadamantane) and related compounds (e.g., rimantadine (9.30))
are available commercially for the prophylactic treatment of influenza A. Amantadine is
not active against many strains of the influenza virus, which is a disadvantage when one
considers the great variability of the virus. Amantadine is a cyclic amine that inhibits
the uncoating of the viral RNA of influenza A. Fortuitously, amantadine is also an
antiparkinsonism drug, acting as a cholinergic blocking agent—a totally unrelated effect.
Amantadine has even been used to treat fatigue in multiple sclerosis.

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