Results from a study presented today at the European Scientific Working Group on Influenza (ESWI) congress in           Malta , show that treatment with the oral ‘flu drug Tamiflu (oseltamivir), significantly decreases the risk of  influenza-related complications such as pneumonia. [i]

Influenza affects up to one in 10 adults and one in three children annually [ii] .Complications include pneumonia, bronchitis, sinusitis, and ear infection (otitis media), which in serious cases can result in hospitalisation and even death. Children, the elderly and people with chronic respiratory or cardiovascular diseases are most at risk.

Today’s data complement existing clinical trial evidence where those treated with oseltamivir demonstrated a 67 percent reduction in secondary complications.[iii] 

The study, using data from a large US health insurer, investigated the incidence of pneumonia, heart attacks and death during the month following influenza diagnosis in patients who either received no medication (136,799) or who were prescribed oseltamivir (39,202). The active treatment was associated with a significantly reduced risk of pneumonia, death and possibly heart attacks, compared to untreated patients.¹

“We know that Tamiflu leads to a significantly reduced incidence of influenza-related complications in a clinical trial setting,” comments Dr Beth Nordstrom, epidemiologist, lead investigator of the mortality study described above. “The results of our new study are valuable as they reveal, in a large population of “real-world” influenza patients, that there is a lower risk of complications and death among Tamiflu users than among individuals who did not receive treatment.”

Influenza-related complications generate additional costs for the healthcare system, both from an outpatient and inpatient perspective. Data from large hospital surveys conducted in the USA show that the rate of hospital admissions increases significantly during influenza epidemics.⁴

           Notes

           About Tamiflu (oseltamivir)
Tamiflu is designed to be active against all clinically relevant influenza viruses.[iv] It works by blocking the action of the neuraminidase enzyme on the surface of the virus. When neuraminidase is inhibited, the virus is not able to spread to and infect other cells in the body.

:         Tamiflu delivers

·         38 percent reduction in the severity of symptoms⁵

·         67 percent reduction in secondary complications such as bronchitis, pneumonia and sinusitis in otherwise healthy individuals³

·         37 percent reduction in the duration of influenza illness[v]

·         Tamiflu was shown to provide up to 89 percent overall protective efficacy against clinical influenza in adults and adolescents who had been in close contact with influenza-infected patients[vi]

In children, Tamiflu delivers:

·         36 percent reduction in the severity and duration of influenza symptoms[vii]

·         44 percent reduced incidence of associated otitis media as compared to standard care[viii]

About the study

The study, reduction in influenza complications following oseltamivir use by Nordstrom et al. was a retrospective cohort study of influenza infected patients conducted using claims data from a large US health insurer.

·        The study involved patients with a diagnosis of influenza during one or more influenza seasons from 1999 to 2004 who received oseltamivir or no treatment

·         39,202 influenza infected patients prescribed oseltamivir and 136,799 influenza patients without antiviral treatment were identified for the study

·        There was a significant (p < 0.001) reduction in risk for pneumonia and death (p = 0.02) in the oseltamivir treated group compared to the untreated group.

·        The risk of heart attack was lower in the oseltamivir treated group however the effect failed to achieve statistical significance (p = 0.06). 

·        Oseltamivir use was associated with a reduction in the risk of pneumonia and death

Pandemic Stockpiling

The World Health Organization (WHO) advises that stockpiling antivirals in advance is presently the only way to ensure that sufficient supplies are available in the event of a pandemic. Roche has been working with many governments over the last few months to discuss their needs for stockpiling of Tamiflu and has received and fulfilled orders from around 30 countries. The magnitude of these orders varies from country to country: for instance, France , Finland , Iceland , Ireland , Luxembourg , Netherlands , New Zealand , Norway , Switzerland , and the UK are stockpiling or intending to stockpile adequate Tamiflu supplies to cover 20-40% of their population.  In order to meet the government needs, Roche has taken steps to increase manufacturing capacity, doubling manufacturing capacity both in 2004 and again in 2005, with a further increase planned in 2006. In addition, manufacturing facilities producing Tamiflu have increased from one to three, with a fourth facility available later in 2005.