A new study lends support to the Centers for Disease Control and Prevention's (CDC) move in January to recommend early, aggressive treatment with antiviral drugs in patients who present with symptoms of the flu. The new research, conducted by investigators at the University of Michigan, the London School of Hygiene and Tropical Medicine, and the University of Alabama, and published online in The Lancet, found that oseltamivir, which is marketed as Tamiflu, can shorten the duration of symptoms by about a day, and reduces by 44% the development of respiratory infections.1
Previous research has questioned the effectiveness of antiviral drugs, especially in light of side effects from the treatment, which can include nausea and vomiting. However, investigators from the latest research say previous studies combined patients who were infected with the flu with patients who were not infected, which diluted the positive impact of the treatment.
The new research included a meta-analysis of data from all the published and unpublished trials between 1997 and 2001, involving 4300 patients, more than half of whom were treated with oseltamivir. The researchers found that when the drug was prescribed at its normal dosage of 75 mg twice/day for adults within 36 hours of the first onset of symptoms, the duration of illness was reduced by 21%.
Further, in addition to reducing respiratory tract infections requiring antibiotics, investigators found that the drug decreased hospital admissions by 63%.
However, the new findings are not likely to quiet the controversy over antivirals. Some researchers are already questioning the new findings, noting that Roche, the company which markets oseltamivir, provided funding for the study, and that one of the researchers involved works for Gilead Sciences, a pharmaceutical company that owns patents on oseltamivir.
- Dobson J, Whitley R, Pocock S, Monto A. Oseltamivir treatment for influenza: A meta-analysis of randomized controlled trials. Lancet 2015; DOI: http://dx.doi.org/10.1016/S0140-6736(14)62449-1.