A new study found that the popular antiviral, Roche's Tamiflu, effectively cuts flu symptoms by a day and helps avoid complications that might lead to hospitalizations. The findings contradict an earlier notion that Tamiflu is ineffective.
Tamiflu works by blocking the enzyme activity that occurs in influenza type A and type B viruses.
Researchers at the University of Michigan, the London School of Hygiene and Tropical Medicine and the University of Alabama worked together in analyzing the efficacy of Tamiflu. They performed a meta-analysis of data from all clinical trials between 1997 and 2001 that involved more than 4,300 patients; half of them were given Tamiflu during the study period. Most of the participants were found to have influenza type A.
The participants who received 75 mg of Tamiflu twice a day within 36 hours of showing flu symptoms reduced their recovery period by 21 percent. The symptoms were reduced as early as 98 hours compared to 123 hours of placebo. It also reduced the risk of respiratory tract infections by 44 percent and hospital admissions by 63 percent.
"This is the first patient-level analysis of how well this drug works. Previous research has questioned its success and use in light of the side effects of nausea and vomiting, but the other studies combined those infected with influenza and those without, which diluted the positive effect of treatment," study co-author Dr. Arnold Monto of the University of Michigan School of Public Health said in a university news release.
The researchers noted some complications such as nausea and vomiting, which echoed the findings of other studies. But contrary to other studies, they did not find a link between Tamiflu and mental disorders.
"Whether the magnitude of these benefits outweigh the harms of nausea and vomiting needs careful consideration," Dr. Monto told Reuters.
The study was published in the Jan. 29 issue of The Lancet.
