Roche received a positive opinion from the Committee for Medicinal Products for Human Use (CHMP) for its 30mg and 45mg dose capsules back in July, shortly after gaining approval for the lower doses in the US. Roche was however unable to say definitively when the lower dose formulations would be available, stating that although it will be supplied to EU countries as soon as possible, it is likely to vary between countries. In the UK, for example, the smaller capsules will not be available until the end of December this, by which time the flu season is likely to be in full swing. Up until now, Tamiflu had only been available as a 75mg capsule, or as a powder for oral suspension for use in children. The approval of these lower doses in capsule form will provide a much more convenient option for paediatric patients, although the syrup form will also remain available. Tamiflu is a member of the neuraminidase class of drugs, and is the only such drug approved for use in children as young as one year old for the treatment and prevention of influenza types A and B. The lower dose capsules will follow the same administration routine as the currently available 75mg adult dose, but the exact regimen will depend on the weight of the child, for example a combination of the 30mg and 45mg capsules could be required to achieve an appropriate dose in some children. The low-dose capsules have a considerably longer shelf-life than the suspension formulation, five years as opposed to two, and require much less storage space - significant advantages in terms of stockpiling to protect against a pandemic outbreak. As yet, however, few governments have stockpiled paediatric antiviral formulations, according to Roche. The new capsules themselves will be smaller than the 75mg version, with less of the active ingredient filled in the capsule, but will require the same drawn out manufacturing process as the existing formulations. The production process for Tamiflu is complicated, involving 10 main steps including complex processes such as azide chemistry. Manufacturing takes around six to eight months once the raw materials are in place, but according to Roche it would take any company starting from scratch two or three years to be able to produce the treatment on a large scale. As such, the company is sitting in an enviable position, with Tamiflu currently the drug of choice among governments seeking to protect their countries against the threat of pandemic flu. Not only this, but according to the company Tamiflu is also currently the only antiviral treatment strongly recommended by the World Health Organization for treatment of patients infected with the avian flu virus, H5N1. Roche ramped up production capacity for Tamiflu following bulk orders and high demand for the drug in the wake of warnings about the threat of flu pandemics and scares resulting from cases of avian flu in humans. Between 2004 and 2006, the company increased production capacity 15 fold, upping capacity to 400 million doses through a global manufacturing network involving 19 partner companies in 10 different countries, as well as other third party manufacturers. However, earlier this year, the company realised that production was well in excess of demand, having received government orders to date totalling around 220 million courses. With these orders all about to be fulfilled, the company decided to scale back production in line with current demand, though continues to maintain a buffer stock of intermediates and active ingredient oseltamivir in order to respond rapidly should an increase in production be required. Tamiflu itself is a member of the neuraminidase class of drugs, active against all clinically relevant influenza viruses. It is the only such drug to be approved for use in treatment and prevention of influenza in children aged one to five years, according to the company. While the 2006/2007 flu season was relatively mild, resulting in lower demand for Tamiflu for seasonal use, sales of the drug in the first half of 2007 were still impressive. Roche's figures showed a 39 per cent increase (in local currencies) in sales of Tamiflu over the first half, coming in at around CHF1.3bn (€0.8bn). Tamiflu represented 7 per cent of sales in Roche's pharmaceutical division, and was one of the unit's highest sellers, coming in fourth under MabThera/Rituxan (rituximab), Herceptin (trastuzumab) and Avastin (bevacizumab).