The results of clinical trials of vaccines involving 11,527 people remain unreported and unused according to a recent study in The BMJ. Researchers looked at 384 vaccine trials registered in at least one of several clinical trial registers between 2006 and 2012. They found that trials took an average of 26 months after ending to publish results in a journal. Results from 19 trials were still not published in a journal or posted on ClinicalTrials.gov six years after the trial ended. The researchers tried to contact the people and institutions responsible for those trials but were unable to find out anything more.
The researchers also found that one year after ending results from 12% of the trials had been published in a journal, while four years after ending results from 73% of trials had been published in a journal. A few trials only posted results on ClinicalTrials.gov, and when those were added to the trials published in a journal, results were available for most – 82% – of the trials four years after the trial ended. Delays in publishing results were similar for trials sponsored by and those not sponsored by industry. When the researchers looked at the results of the trials, the trials not sponsored by industry were over 4 times more likely than industry sponsored trials to report negative or mixed results.
11,527 people were involved in the 19 trials whose results are still hidden. Patients who have participated in vaccine clinical trials have told us that they volunteered for clinical trials in the hope of helping other people in the future through new advances in medicine. They put themselves at risk and allowed the trial to intrude on their daily lives. It is a betrayal of their trust that these results remain unreported and unused.