W-03: Searching the Registries for Trial Submission QA and Competitor Intelligence - Comparing ClinicalTrials.gov and EudraCT
Lead Developer, Analytics & Custom Solutions
BizInt Solutions, Inc. United States
Do searches of clinical trial registries reveal differences in how the same trial is entered in different countries? Can registry searches help a company identify discrepancies in how a trial has been entered in different countries? And might these discrepancies mean richer competitor intelligence?
We searched both US and European registries for a set of checkpoint inhibitor drugs using the same search terms.
We compared the content of records from both registries for the same trial. Records were considered to be about the same trial if they included at least one shared trial identifier.
For a search of the checkpoint inhibitor tremelimumab we found 208 total records and 98 trials. From those we identified 23 trials with records in both registries. 82% of trials showed different information in at least one of these three shared fields: drug names, sponsors, and countries. Differences for the three fields were: 30%, 35%, and 74% respectively.
Differences in drug name could mean using a lab code versus a generic name, but also included cases where a drug was found in one record only. For one phase 3 trial EudraCT records didn’t list one comparator drug, temozolomide, though it was in the trial title.
Sponsor and country differences always meant additional sponsors or countries in some records. ClinicalTrials.gov records were found with commercial sponsors not referenced in EudraCT. In one phase 2 trial, Pfizer was listed in the US record, but the EudraCT record listed no commercial sponsor. In another set of trials US records listed AstraZeneca and EudraCT, Pfizer.
EudraCT records in 4 trials listed only one country. For a phase 2 trial the US was listed as a location in EudraCT only. For a given trial, records from both registries included countries not found in other records.
All trials listed different trial identifiers in the two sources, making identifying records for a trial in both registries problematic. For 43% of trials no records included the identifier for the other registry. Two trials found in EudraCT and 73 trials in ClinicalTrials.gov could not be matched to the other registry based on trial identifiers listed. Of the trials found only on ClinicalTrials.gov, 10 listed European countries. One was a phase 3 trial with a EudraCT number listed but the trial was not found searching EudraCT.
Similar results were found with 62 trials for another drug, Pembrolizumab. Here 90% showed a difference in at least one of drug name, sponsors, and countries. One notable difference in this set: 15 US records did not list any countries.
These results have implications from both a regulatory and a competitive standpoint. As we talk about harmonisation and as both registries are accessible to a global audience, the content presented on a company's trials should be the same. Review is needed to ensure that a company's submissions to either registry don't contain additional or different information. From a competitive standpoint, the differences offer a competitive advantage when you search multiple sources and integrate information into your review.