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What role could TAMIFLU play in a pandemic?
TAMIFLU to play dual role: prevention and treatment
The antiviral TAMIFLU could play two principal roles in the management of seasonal flu:
- Prophylaxis - aimed at decreasing the likelihood of developing flu
- Treatment - aimed at reducing the duration of flu by 1.3 days
Research has demonstrated the effectiveness of antivirals when used for both purposes.
When used for treatment purposes, these drugs need to be administered within 48 hours
after the onset of symptoms.22a
Tamiflu has been studied only in strains of the influenza virus that were circulating at the given time. The magnitude of effect of Tamiflu in treating and preventing novel strains of influenza cannot predicted.
The Centers for Disease Control, along with an interagency working group with representatives from State, local and tribal public health agencies, drafted guidance on antiviral use strategies and stockpiling. The working group recommends the following strategies and settings for antiviral use: 22a
- Containing or suppressing initial pandemic outbreaks overseas and in the U.S. with treatment and post-exposure prophylaxis (PEP) among individuals identified as exposed to pandemic influenza and/or geographically targeted prophylaxis for geographic areas where exposure is thought likely to occur;
- Reducing introduction of infection into the United States early in an influenza pandemic by post-exposure prophylaxis of exposed travelers as part of a risk-based policy at U.S. borders;
- Treatment of persons with pandemic illness who present for care early during their illness and would benefit from such treatment;
- Prophylaxis of critical health care workers, emergency service personnel, and workers with unique roles maintaining critical infrastructures for the duration of community outbreaks;
- Post-exposure prophylaxis of household contacts of persons with influenza illness as a component of community mitigation
- Post-exposure prophylaxis of workers in the health care sector with limited patient contact, of persons with compromised immune systems who are unable to be protected by vaccination, and of persons living in closed settings such as nursing homes and prisons if a pandemic outbreak occurs at that facility.
Expert recommendations for pandemic flu management 30
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Recent studies based on mathematical modeling suggest that antivirals could be used prophylactically near the start of a pandemic to reduce the risk that a fully transmissible virus will emerge (or at least delay its spread internationally), thus gaining time to augment vaccine supplies.
This research has not been conducted in patients. Results are not based on a clinical study, but on mathematical modeling, which has significant limitations.
- The World Health Organization (WHO) recommends TAMIFLU for the prevention of pandemic influenza disease
in household contacts. This recommendation is based on the effectiveness of TAMIFLU in preventing ordinary
influenza in healthy and elderly patients and children ages 1 year and older. 31
Experts look to neuraminidase inhibitors for pandemic flu
- TAMIFLU and Relenza are antivirals that belong to a drug class known as neuraminidase inhibitors. In laboratory studies,
the neuraminidase inhibitors have been shown to reduce the duration of illness caused by seasonal influenza.34
The efficacy of the neuraminidase inhibitors depends on their administration within 48 hours after symptom onset. Studies are
currently underway to examine the efficacy of TAMIFLU against potential pandemic strains of influenza.32
- Another class of antiviral drugs, the M2 inhibitors amantadine and rimantadine, could potentially be used against pandemic
influenza, but resistance to these drugs may develop.35
-HHS Pandemic Plan
For more information about Tamiflu resistance, please see
What is the TAMIFLU resistance profile?
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