Roche AG's Tamiflu and another influenza drug GSK's Relenza can shorten the symptoms of influenza by about half a day earlier, but do not reduce the severity of its complications.

A research by the Cochrane Collaboration, a nonprofit network of health practitioners, unveiled the same after analyzing 46 clinical study reports on both the drugs. The assessment has clearly unveiled that the drugs may not work well as expected by the federal government when it spent more than $1.3 billion on stockpiling them.

Researchers said the drugs would not be able to reduce the rate of complications, including hospitalization and pneumonia. Professor Chris Del Mar from Bond University, author of the research, said the result may make them think about not using drugs in that way as these drugs just provide symptomatic relief.

It might be news for many, but not for the FDA as it got to know in 1991 that Tamiflu does not reduce influenza-related complications. Another thing revealed through the study was that Tamiflu appear to react differently in children and adults.

The drug was able to reduce influenza symptoms in children without asthma by 29 hours. On the other hand, Tamiflu does not shorten the length of symptoms in children with asthma.

The research also focused on the preventative use of Tamiflu and Relenza. It was unveiled that both of them decreased the rate of symptomatic influenza, but not of asymptomatic influenza. It means that people taking drugs could still spread the virus.

Roche, Tamiflu's maker, said they would continue to stand by the data supporting the efficacy and safety of the drug. "Tamiflu has been reviewed and approved by regulatory authorities in over 80 countries, it is recommended as a flu antiviral by public health bodies, including the World Health Organization".