Blockchain technology is making inroads into healthcare. The hype surrounding blockchain, in particular in its association to crypto-currencies, has led to a surge in its applications to health data management and supply-chain processes. Between 2016 and 2019, the European Commission’s Healthcare 2020 programme has contributed approximately €31.1 million to healthcare blockchain projects, coming in third behind cybersecurity and IoT research and development. Private companies are following suit, with recent initiatives such as the MediLedger Network, which brings together Big Pharma and other industry leaders – including Pfizer, Eli Lilly, McKesson, and Walmart.
Among other areas of health, clinical research has a lot to benefit from blockchain and associated technologies. At a time when data regulators, HTA agencies, and patients expect more data safety and accountability from investigators, blockchain has the potential to enable more ambitious clinical methodologies, incorporating complex designs and technological advances while improving trust in existing research practices.
Blockchain networks typically use asymmetric cryptography involving public and private keys. Under asymmetric cryptography, the public key is shared openly on the network and allows all users to identify themselves (and their operations) as well as identify other users and operations. Private keys, kept secret by authorised users, are used to sign transactions, providing proof of ownership and authorisation. This ensures that only autorised users can access or transact the data stored in the blockchain. It also allows to attach levels of authorisation to different keys, so that data are identifiable on a need-to-know basis and anonymous the rest of the time.
Many different protocols implement asymmetric cryptography – an everyday example being HTTPS. However, blockchain is distributed in a way that no single user can delete data records. If a user wants to edit data (e.g. in good faith if it has been entered incorrectly), they need to submit a new record which is visible to other users. As a result, blockchain provides additional safeguards against the accidental, unauthorised, or unilateral alteration of data.
Privacy is crucial when dealing with sensitive patient data. The blockchain framework combines safety with the transparency needed to address tampering by ill-intentioned investigators, by requiring consensus among researchers before effecting any alterations and providing straightforward ways to audit data records.
The digitisation of recruitment and consent management on a blockchain platform helps researchers and patients to access consent status – and potentially withdraw consent – in real time. In addition to reducing administrative burdens and enhancing the transparency of participant information, this is consistent with notions of reversibility of consent imposed by regulations such as Article 7(3) of the EU General Data Protection Regulation.
Blockchain can also help in adhering to other regulatory requirements in clinical research. Since the technology allows for transparent and immutable record-keeping, it makes it easier to demonstrate compliance with regulatory standards, which is essential in trials conducted for the purpose of a marketing-authorisation application.
Other improvements which blockchain technologies can bring to existing practices include:
Those advantages allow to envision research designs which would otherwise be impractical or compromise patient privacy.