Martek Biosciences ( MATK) has been chosen by drugmaker Roche to help it produce the main ingredient for Tamiflu, an influenza drug. Worries about an avian flu pandemic have led more than 60 countries to order stockpiles of the drug from Roche, and the vital ingredient, shikimic acid, is in short supply. Shares of Martek were up 4 cents at $34.02, but had been as high as $37.22 earlier in the session. Shikimic acid comes from the Chinese star anise fruit, which is grown seasonally under specific climactic conditions. Martek said it can take up to six years for a new tree to bear fruit. The company, among a number of manufacturers Roche has chosen worldwide, would use a fermentation process to make the acid and provide it to Roche on a more consistent basis than the naturally derived version, Martek said Thursday. "In a relatively short period of time, Martek's scientists and engineers have been able to work with Roche to implement a commercial-scale production process using Martek's equipment," Martek said in a press release. "This success has helped Roche reduce its dependence on the Chinese star anise fruit as a source of shikimic acid." However, Martek notes that its sales of shikimic acid may not be material in its 2006 fiscal year. Although there is potential for additional sales to Roche after this year, sales would be dependent on future demand for Tamiflu and on whether Roche wants to continue the relationship. Outbreaks of the H5N1 avian flu, almost exclusively in Asia, have created sporadic panics in recent months, leading the mainstream media to produce countless stories envisioning various doomsday scenarios. The fear is that this particular strain of the bird flu, which has occasionally been transmitted from birds to humans, could mutate into a human-to-human variant capable of causing widespread deaths around the globe. Poultry farmers have killed millions of birds in an effort to contain the virus. The H5N1 strain has spread westward in recent months and has been reported in a handful of cases in Europe.