Clinical Trial Data Sharing Remains Low Despite Industry Promises

Despite efforts to encourage the sharing of clinical trial data by drugmakers, the availability of this information to qualified researchers remains low, according to an investigative study appearing in JAMA Oncology this week. In recent years, pharmaceutical industry groups have increasingly promoted policies around the sharing of data from clinical studies, but the extent to which these data are actually made available is unclear. To investigate, a group led by scientists from Flinders University in Australia examined the availability of individual participant data (IPD) from 304 clinical trials that supported the registration of 115 anticancer drugs with the US Food and Drug Administration between 2011 and 2021. Of these trials, the researchers find 168 — 55 percent — were not eligible for IPD sharing, with the most common reason for the lack of data sharing being that the collection of long-term follow-up data was still ongoing. Notably, three of the top 10 cancer drugs based on global sales had the lowest eligibility rates for IPD sharing at less than 10 percent of trials. "Because these trials form the basis of safety and efficacy claims for new medicines, we question whether it is justified that the data are unavailable to independent scrutiny," the study's authors write. "On the basis of our findings, we reiterate calls that transparency policies need updating so that all IPD that inform results presented in a product label or underpin drug registration are immediately eligible for sharing."