A systematic review of Roche’s antiviral drug Tamiflu appearing in last month’s Cochrane Library has led to questions about the data’s efficacy, as well as Roche’s commitment to provide sufficient data.

“We found a high risk of publication and reporting biases in the trial programme of [Tamiflu],” Cochrane Collaboration researchers wrote.

Evidence confirms Tamiflu shortened length of symptoms vs. placebo. Other findings question its mechanism of action but could not be properly assessed without access to the full document set. The paper “has raised challenges for all those engaged in conducting systematic reviews,” wrote Cochrane editors.