Results of nearly half of all clinical trials conducted in the last decade by big drug companies have not been published, according to an analysis of data from TrialsTracker, an online tool that identifies trials from ClinicalTrials.gov that haven’t published results 2 years after the end of the trial.

TrialsTracker was developed by the AllTrials consortium, a group calling for the results of all clinical trials to be published. The tool includes sponsors with more than 30 interventional trials and excludes phase 1 trials.

According to the analysis, since January 2006, trial sponsors completed 25,927 eligible trials and haven't published results for 11,714 trials, or 45.2%. These 11,714 trials with missing results enrolled an estimated 8.7 million patients.

"We should all be outraged" by this, Síle Lane, director of campaigns at Sense about Science, which runs the AllTrials campaign, said in a news release.

"Everyone has been talking about this problem for far too long. We hope that increasing accountability will help to drive change forward. The TrialsTracker helps to identify the individual universities and companies with the most overdue trials," added Ben Goldacre, MBBS, MRCPsych, one of the founders of the AllTrials campaign for clinical trial transparency and one of the researchers behind the TrialsTracker.

Dr Goldacre, and coauthor Anna Powell-Smith, with the Evidence-Based Medicine Data Lab, University of Oxford, United Kingdom, reported their analysis of TrialsTracker data online November 3 in F1000Research.

Drug Companies Dispute Findings

The analysis found that Sanofi had the largest number of missing trial results — 285 missing results from 435 eligible trials (65.5%).

But Ameet Nathwani, MD, chief of medical affairs for Sanofi, told Medscape Medical News the company "disagrees with the AllTrials analysis, which does not capture many of our publicly available clinical trial results. In fact, of the 285 study results deemed missing by AllTrials, Sanofi has made publicly available results for 255 (90%) of these studies on either the EU Clinical Trials Register or the Sanofi website. This means that, in total, Sanofi has made publicly available the results for 93% of the 435 studies identified by AllTrials, making us one of the most transparent clinical trial sponsors in the world.

"We respect and follow all relevant governmental regulations concerning the disclosure of clinical trial results," Dr Nathwani added.

The analysis also found that Novartis did not disclose data for 201 of 534 eligible studies (37.6%).

In a statement emailed to Medscape Medical News, Novartis said: "We are aware of the TrialsTracker initiative and are reviewing against our own records. Initial analysis suggests the data presented is misleading as it focuses on PubMed and clinicaltrials.gov records, but doesn’t include other publication outlets including our own clinical trials results website (www.novartisclinicaltrials.com)."

"Novartis is committed to clinical data transparency and has been registering clinical trials on clinicaltrials.gov since 1999. In May 2005, Novartis became one of the first companies to publish interventional clinical trial results within one year of trial completion, regardless of outcome, on a public website. This pre-dates any country regulatory requirement to make trial results public," the company said.

GlaxoSmithKline didn't publish findings for 183 of 809 eligible trials (22.6%), the analysis found. And India-based Ranbaxy Laboratories Ltd (now part of Sun Pharma) hasn't published any results for any of the 35 trials it has conducted in the last 10 years. GlaxoSmithKline and Sun Pharma did not respond to a request for comment by press time.

The analysis also found that some drug companies have done a good job of publishing results, with Shire Pharmaceuticals leading the pack, having published results for all of the 96 trials it has run in the last 10 years.

The other top trial sponsors with the lowest number of missing results are reported by the initiative at the F1000Research site.

The TrialsTracker is automatically updated when new information is added to the clinical trial register ClinicalTrials.gov. The information in the analysis is current up to November 2, 2016.

F1000Research. Published online November 3, 2016. Full text

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