Blockchain could help ensure clinical trial integrity

“We showed that a blockchain-based file and data structure could be used to reliably safeguard data in a clinical trials network, and provide an immutable and fully traceable audit trail,” say Atul Butte, from the University of California, San Francisco (UCSF) and colleagues.

Writing in Nature Communications, the researchers explain that monitoring and ensuring the integrity of data within the clinical trial process is currently not always feasible. “Clinical trial networks often involve many parties and sites, and a large flow of information and confidential data. With the involvement of more parties, more exchanges, and trials being conducted far from sponsoring institutions comes the opportunity for human-induced error, whether it is unintentional or malicious,” they say.

Daniel Wong, a PhD candidate in Biological and Medical Informatics at UCSF, built the system to operate through a web portal, so that each time new data is entered on a given trial participant, the sender, receiver, timestamp, and file attachment containing the data, along with the hash of the previous block of data pertaining to that patient, is recorded onto a new block, with its own distinct signature.

Unlike many blockchain applications, this clinical trial prototype depends on having a regulator with centralised authority, such as the US Food and Drug Administration, to operate the web portal, register all parties, and keep a ledger of the blockchain’s hashes.

Data, including adverse events, would be reported to the regulatory agency in real time, which may provide a boost to the safety and efficiency of clinical trials. While the prototype makes allowances for data entry or other errors to be corrected, new data can only be appended to the existing chain, without erasing what was there before.

“Everyone is talking about how blockchain is going to revolutionize many of the data challenges in medicine, and here is one use that finally might make sense,” says Butte.

Wong tested the system with a small subset of data from a real, previously run phase II trial included in ImmPort, a repository of open clinical trial data funded by the National Institutes of Allergy and Infectious Diseases (NIAID) that is managed by Butte’s lab and collaborators.

After entering the original data, he logged in as the trial sponsor and tried to erase adverse events that had been reported for two patients in their case report forms. Instead of deleting those reports, however, the system appended his changes to the original data, making it clear who had tried to corrupt the forms, when it was done, and what had been changed.

Wong also tried corrupting the data stored from an earlier point in the trial, when patients were assigned to different treatment arms – drug or placebo – to make it look as though they had been given a different medication plan. But the blockchain ledger pinpointed exactly what had changed and when.

“A system built upon our prototype could be developed to enable oversight of international clinical trials, for example,” Butte said. “And it could be expanded to provide more access to raw data for research scientists, the way we do with ImmPort, or deliver trial results to the public.”