Hoffmann-La Roche (Roche) (Indianapolis, IN, USA), is the market leader of the neuraminidase inhibitors
(NAI), the first class of antiviral drugs designed specifically to treat influenza.
In vitro generation of neuraminidase inhibitor
resistance in A(H5N1) influenza viruses.
Susceptibility of virus isolates to the neuraminidase inhibitors
(NAIs), including oseltamivir and zanamivir and two investigative NAIs (peramivir and A-315675), was assessed by chemiluminescent neuraminidase inhibition assay using the NAStar Kit (Applied Biosystems, Foster City California) (4).
* Comment: Tamiflu is one of two available neuraminidase inhibitors
, which work by blocking the influenza enzyme that promotes viral release from infected cells.
The limited effect of oseltamivir on reducing disease duration, usually only shortening the duration by 1 day in healthy persons (4), the possibility of serious side effects (5), the possibility of the virus developing resistance to neuraminidase inhibitors
(6,7), and the cost to health care of unnecessary prescriptions are reasons to strive for better adherence to prescribing guidelines.
To reduce the burden of influenza in the United States, CDC continues to recommend a three-pronged approach: 1) influenza vaccination, 2) use of neuraminidase inhibitor
antiviral medications when indicated for treatment or prevention, and 3) use of other measures to decrease the spread of influenza, including promotion of hand hygiene, respiratory hygiene, cough etiquette, and staying home from work and school when ill.
Two classes of antiviral medications are available currently: adamantanes or M2 ion channel inhibitors (i.e., amantadine and rimantadine) and neuraminidase inhibitors
(i.e., oseltamivir and zanamivir).
The adamantanes are ineffective against influenza B viruses, which limits the available antiviral options to 2 neuraminidase inhibitors
(NAIs), inhaled zanamivir and oral oseltamivir.
But the virus appears sensitive to the neuraminidase inhibitor
Nonetheless, the data show that people get better 1-2 days sooner with neuraminidase inhibitor
Amantadine and rimantadine are approved for treating influenza A, while the neuraminidase inhibitor
drugs zanamivir and oseltamivir are approved to treat both influenza A and B [6-8].
-- Forget the fact that treating influenza with a neuraminidase inhibitor
can reduce the duration of symptoms by 1-2 days.