Roche to expand Tamiflu manufacturing capacity

Roche has been granted US FDA approval of an additional capsule manufacturing site in the US for the supply of the influenza antiviral Tamiflu (oseltamivir), expanding its already significantly increased worldwide production capacity. This facility is part of a network of more than a dozen production sites for Tamiflu worldwide, more than half of which are with third party manufacturers.

Tamiflu is designed to be active against all clinically relevant influenza viruses. It works by blocking the action of the neuraminidase (NAI) enzyme on the surface of the virus. and key international research groups have demonstrated, using animal models of influenza, that Tamiflu is effective against the avian H5N1 strain circulating in the Far East. Roche has been working with many governments over the last few months to determine their needs for stockpiling of Tamiflu and has received and/or fulfilled orders from around 40 countries.

'For Tamiflu, the key need today is the rapid expansion of production capacity,' said William M. Burns, ceo Roche Pharma Division. 'We have already significantly expanded production capacity internally and by working in close collaboration with other companies, and we will continue to do so. In addition, we are prepared to discuss all available options, including granting sub-licenses, with any government or private company who approach us to manufacture Tamiflu or collaborate with us in its manufacturing.'

Tamiflu has been shown to deliver a 38% reduction in the severity of symptoms, a 67% reduction in secondary complications, and a 37% reduction in the duration of illness. It was also shown to provide up to 89% overall protective efficacy against clinical influenza in adults and adolescents who had been in close contact with influenza-infected patients.

In children, Tamiflu delivers a 36% reduction in the severity and duration of influenza symptoms and a 44% reduced incidence of associated otitis media as compared to standard care.

As with any antiviral, a theoretical potential exists for an influenza virus to emerge with decreased sensitivity to a drug. Extensive monitoring, by Roche and the independently established Neuraminidase Inhibitor Susceptibility Network (NISN) measured the incidence of resistance to NAIs. From around 4000 patients treated with Tamiflu resistance was encountered in 0.4% in adults and 4% in children. This resistant virus was found to be less virulent than the wild type virus and did not affect the course of the illness.

The World Health Organisation (WHO) has recommended as part of its Pandemic Preparedness Plan that countries establish stockpiles of antiviral treatments such as Tamiflu, which are effective against all strains of the influenza virus.