Tamiflu(R) in Ample Supply for Prevention & Treatment of Seasonal Flu
Roche announced that its prescription antiviral medication Tamiflu(R) (oseltamivir phosphate) will be in ample supply during the 2006-2007 flu season in pharmacies across the U.S., with more than double the stock available last season.
Tamiflu is indicated for the treatment and prevention of influenza in adults and in children 1 year and older.
"During the past year, Roche has continued to take all necessary steps to ensure that Tamiflu is available for pandemic preparedness as well as seasonal flu, in keeping with the recommendations of public health officials and the needs of our customers," said George Abercrombie, President and CEO, Hoffmann- La Roche Inc. "Physicians can be confident that Tamiflu will be readily and widely available to patients who need it for flu treatment and post-exposure prevention."
While Tamiflu has been widely associated with pandemic preparedness, it was developed for seasonal flu prophylaxis and treatment. Roche has a proactive inventory management plan in place that is designed to ensure that Tamiflu is available to patients when and where it is needed.
According to recommendations issued in June by the U.S. Centers for Disease Control and Prevention, oseltamivir (Tamiflu) and zanamivir (Relenza) should be prescribed if an antiviral medication is needed for seasonal flu treatment or prophylaxis. Due to high levels of resistance, CDC recommends against the use of two other antiviral agents, amantadine and rimantadine, until susceptibility of these agents has been re-established among circulating influenza A viruses.
Influenza is a serious illness that affects up to 40 million Americans every year, causing disruption to their daily lives, and leading to 200,000 hospitalizations and 36,000 deaths annually. In a typical year, it is estimated that influenza may result in as much as $10 billion in lost productivity.
While vaccine is the first line of defense against seasonal influenza, prescription antiviral medications like Tamiflu play an important role in prevention and treatment of influenza. Prophylactic use of antivirals is recommended by the CDC for people at high-risk of influenza as well as health care workers and institutional settings, such as nursing homes.
How Tamiflu Works
Tamiflu belongs to a class of antiviral medicines called neuraminidase inhibitors (NAI), which help prevent the flu virus from spreading inside the body. Virtually all common flu viruses have the neuraminidase protein on their surface, which enables them to migrate from cell to cell, replicating and spreading throughout the body. Inhibiting the neuraminidase activity is believed to interfere with this process, possibly causing the viruses to become trapped and die out. Tamiflu is given orally and is systemically absorbed, meaning that it can reach all key sites in the body where the virus multiplies.
When taken within 48 hours of symptom onset, research shows Tamiflu can reduce duration of illness by 1.3 days. Clinical trials also indicate that Tamiflu is up to 89 percent effective in preventing flu, when taken within 48 hours of exposure.
Tamiflu Manufacturing Capacity
The broad availability of Tamiflu for both seasonal and pandemic use is due to expanded global production capacity, which will reach the rate of 400 million treatment courses annually by the end of 2006, a more than 10-fold increase since 2004. The expansion includes a fully functioning U.S.-based supply chain for Tamiflu with an annual capacity of 80 million treatment courses. With Roche sites as well as external contractors throughout the country, the U.S. supply chain encompasses all aspects of Tamiflu production, from synthesis of the initial starting material (shikimic acid) through all major steps of manufacturing to finished packs. It was developed by Roche at the request of the U.S. Department of Health & Human Services (HHS).
Roche and its affiliates have received and are filling on schedule orders from more than 75 countries to-date for stockpiling Tamiflu. Roche's global network for the manufacture of Tamiflu includes several Roche sites and more than 15 external contractors located in nine different countries around the world.
Tamiflu, co-developed by Gilead Sciences, Inc., based in Foster City, CA, is a systemic treatment for the most common strains of influenza (types A and B). Tamiflu is indicated for the treatment of uncomplicated influenza caused by viruses types A and B in patients one year and older who have been symptomatic for no more than two days. Tamiflu is also indicated for the prophylaxis of influenza in patients one year and older.
In treatment studies in adult patients, the most frequently reported adverse events (incidence >1%) were nausea and vomiting. Other events reported numerically more frequently in patients taking Tamiflu compared with placebo were bronchitis, insomnia and vertigo. In treatment studies in patients one to 12 years old, the most frequently reported adverse event (incidence >1%) was vomiting. Other events reported more frequently in patients taking Tamiflu compared with placebo included abdominal pain, epistaxis, ear disorder and conjunctivitis.
In prophylaxis studies in adult patients, adverse events were similar to those seen in the treatment studies. Events reported more frequently in patients taking Tamiflu compared with placebo (incidence >1%) were nausea, vomiting, diarrhea, abdominal pain, dizziness, headache and insomnia. In a household prophylaxis trial that included patients one to 12 years old, adverse events were consistent with those observed in pediatric treatment studies, with GI events being the most frequently observed.
Treatment efficacy in subjects with chronic cardiac and/or respiratory disease has not been established. No difference in the incidence of complications was observed between the treatment and placebo groups in this population. Safety and efficacy of repeated treatment or prophylaxis courses have not been studied.
In post-marketing experience, rare cases of anaphylaxis and serious skin reactions, including toxic epidermal necrolysis, Stevens-Johnson syndrome and erythema multiforme, have been reported with Tamiflu.
Vaccination is considered the first line of defense against influenza.
Tamiflu is available for the treatment of influenza in more than 80 countries worldwide.