Tom Jefferson , reviewer 1 , Peter Doshi , assistant professor 2 1Cochrane Acute Respiratory Infections Group, 00187, Roma, Italy 2Department of Pharmaceutical Health Services Research, University of Maryland School of Pharmacy, Baltimore, USA Correspondence to: T Jefferson Jefferson.tom{at}gmail.com

Last year the Cochrane team, with the help of the BMJ’s open data campaign, finally got access to full clinical study reports on neuraminidase inhibitors. Tom Jefferson and Peter Doshi explain what the new systematic review found and how a series of failures meant that decisions about these drugs were made without the full evidence

For the past decade decisions makers worldwide have endorsed the use of neuraminidase inhibitors. They spent billions of pounds stockpiling the two anti-influenza drugs oseltamivir and zanamivir from the mid-2000s as part of a global effort to be prepared for an influenza pandemic. When the H1N1 pandemic emerged in 2009 the drugs were rolled out around the globe for treatment and prevention of influenza and its complications. Under this spotlight, we were asked to conduct a systematic review for Cochrane to update evidence on their efficacy. What should have been a routine review got complicated as the validity of a key study that underpinned the evidence on efficacy was unclear. Our three and half year battle for data has resulted in the drug manufacturers providing us with full clinical study reports and unveiled a story in which no party has taken full responsibility for ensuring the validity of the evidence underlying its decisions. We hope that the publication of our systematic review of the trials, alongside all the source clinical study reports,1 will change the way such decisions are made.