See my previous post on the need for data sharing.  For the past three years, a group of researchers has been trying to gather all of the clinical trial data for the anti-influenza drug Tamiflu (oseltamivir), without success.  As a result there is continuing uncertainty about the benefits — and harms — of the drug.  They tell their story in a New York Times op-ed and an article in PLoS Medicine.  Here is the summary from the PLoS Medicine article:

• Systematic reviews of published randomized clinical trials (RCTs) are considered the gold standard source of synthesized evidence for interventions, but their conclusions are vulnerable to distortion when trial sponsors have strong interests that might benefit from suppressing or promoting selected data.
• More reliable evidence synthesis would result from systematic reviewing of clinical study reports—standardized documents representing the most complete record of the planning, execution, and results of clinical trials, which are submitted by industry to government drug regulators.
• Unfortunately, industry and regulators have historically treated clinical study reports as confidential documents, impeding additional scrutiny by independent researchers.
• We propose clinical study reports become available to such scrutiny, and describe one manufacturer’s unconvincing reasons for refusing to provide us access to full clinical study reports. We challenge industry to either provide open access to clinical study reports or publically defend their current position of RCT data secrecy.

Also in PLoS Medicine, a response by a group of European drug regulators.  The regulators agree that that data secrecy is no longer acceptable but list some reasons for caution.

Peter Doshi and Tom Jefferson, “Drug Data Shouldn’t Be Secret,” New York Times, April 10, 2012.

Doshi P, Jefferson T, Del Mar C (2012) The Imperative to Share Clinical Study Reports: Recommendations from the Tamiflu Experience. PLoS Med 9(4): e1001201. doi:10.1371/journal.pmed.1001201

Eichler H-G, Abadie E, Breckenridge A, Leufkens H, Rasi G (2012) Open Clinical Trial Data for All? A View from Regulators. PLoS Med 9(4): e1001202. doi:10.1371/journal.pmed.1001202

Here is a summary from Pharmalot.