PharmaChain: Proof-of-Concept

A collaboration for clinical trials on the blockchain between Boehringer Ingelheim and TheLedger

Kevin Leyssens


The process of discovering a potentially new drug until it becomes available to patients takes on 15–30 years. And on average brings a cost of 1.3 billion euros. Boehringer wants to speed up and optimise part of this chain. Clinical studies. Because 80% of the clinical trials are delayed.

By working on digitisation and focusing on the patient, Boehringer is convinced that this process is more efficient and therefore faster. The patient owns his own data, enabling him to submit and confirm additions and changes himself. This will increase transparency. The patient knows at any time which data is available and can be viewed by the parties involved.

Digitisation will increase efficiency because information flows to all parties more smoothly and reliably. In case of important new information for the safety of the patient, it can be taken, confirmed and signed directly via the smartphone or tablet, for example. The reliability and data integrity will be increased by blockchain technology. This results in faster and better recruitment.

Find the right hospitals for the right study in an instant and thus recruit the right patients and get the medicine to the patient more quickly.

Not only does this have enormous advantages for the patient, but hospitals can also jump on the boat of digital transformation. By keeping hospital and anonymised patient profiles on the blockchain, it is easier to find the right hospitals for the right study in an instant and thus recruit the right patients and get the medicine to the patient more quickly.

Current process: Paper

Before trials can be executed on humans, they need to run through a complex and intensive process. This process will not be discussed. We’ll start when the trial is verified and accepted for execution by all involved parties.

Boehringer sends out the requirements to conduct the study to several hospitals, after a CDA (Confidential Disclosure Agreement) is signed by those hospitals. What equipment they need, how many doctors, how many patients, etc ….

When a hospital fulfils all the requirements, they can start patient recruitment. After the recruitment, patients fit to participate in the study are selected. These patients need to sign a paper Informed Consent (IC). It explains the whole process, risks, schedules, etc. It needs to be signed with a doctor, so patients can ask any question they have. This Signed Informed Consent (SIC), which is paper, is kept at the hospitals.

Now it gets interesting. Every time something changes about the study, the patient needs to go to the hospital and sign the new informed consent again. Some studies are conducted over a few years, where visits are every X months. If they forgot to go to the hospital to sign the new informed consent and a visit is near to i.e. get some blood, it can not be taken. When the study doctor is not present, the new informed consent cannot be signed, thus the visit needs to be rescheduled, thus delaying the trial.

Our proof-of-concept solution: Hybrid

Patients are anonymised on the blockchain. Only the hospital may link an anonymous patient of the blockchain to a real patient based on the paper signed informed consent that is stored on their own private database.

A hybrid solution for the PoC


There are 3 parties who can view the patients’ data: Boehringer as the pharma company, the hospitals and the patient. Boehringer can see from every anonymous patient its data and actions from the blockchain (not the signed informed consent). The hospital and patient can see both the anonymised data from the blockchain and the signed informed consent.

How does it work?

When a patient is ready to register anonymously on the blockchain, he gets a number. This number is written on the paper informed consent that needs to be signed. This way the anonymous patient’s ID is linked with the identity written down on the informed consent. When registering, the document is uploaded and saved on the private off-chain database of the hospital.

Data integrity of off-chain documents

When the patient is registered, a hash of the document is calculated. This hash, path and version of the document are saved with the anonymous patient on the blockchain. At the first login, the patient needs to sign this uploaded document digitally. So future digital signatures can be compared with this initial one and the patient can digitally check if the document uploaded is the one he signed on paper.

When the patient requests its data, the smart contract will go to the path, get the document, calculates the hash and compares it with the hash saved on the blockchain. If the hash is a mismatch, the user will get an error and the system will know there has been tampered with the uploaded document and measurements can be taken.

Updating through digital signatures

Like mentioned before, the initial document is signed on paper, uploaded and signed digitally. When there is an update of the study and a new informed consent needs to be signed, the patient is notified. He can read this new document from home and sign it digitally in an instant. When having questions, he can call the doctor.

A new informed consent needs to be signed by a minimum of 2 parties: patient and doctor. When the patient signs the new document digitally then the doctor can sign this document when the patient visits. He can only sign after the patient has signed the document due to rules in the smart contract.

Architecture of Proof-of-Concept

Note that the backend service consists of 3 different services: an API-gateway, a chain service to communicate with the blockchain and a document service for the documents uploaded and stored on amazon s3 bucket.

I hope you enjoyed this article. If you got excited about blockchain and want to know how this technology can transform and add value to your business, just contact us @ TheLedger



Kevin Leyssens

Full stack blockchain developer and consultant at TheLedger.