3.1. Potential of Blockchain in the data registry
Blockchain can be vital in addressing challenges that the clinical research community faces, such as reproducibility, personal data privacy concerns, data sharing, and patient registration in clinical trials. The main characteristic of Blockchain that services depend on trusted third authority can be reconstructed in a transparent, secure, decentralized way that enables users to have full control and lets the service be observable; hence, it ensures tracing information and permits for securely automating the clinical trial. Simultaneously, it also provides shareable parameters for patients or clinical trial stakeholders. The potential impact of Blockchain technology implementations in clinical trials will illuminate how recent clinical trial methods could develop and profit Blockchain technologies to confront the challenges mentioned above [16–19]. Figure 5 outlines the strengths, opportunities, weaknesses, and threats of Blockchain.
3.2. Clinical trials of drug development for COVID-19
Nowadays, patients are willing to be more attentive, and their engagement is becoming a great success factor for clinical trials [9]. Patients are assured to agree to the protocol prearranged in the Blockchain when giving consents to contribute to a trial. The smart contract feature guarantees that any protocol change results in patients' consent renewal [10]. This technology also enables main success features, including direct patient engagement, reporting to regulators, and secure data tracking. Through Blockchain's structural characteristics, data transparency can be guaranteed, including decentralization, encrypted immutable records, and trusted time-stamping [12].
Most of the data is being collected from various sources during the current pandemic, including the datasets mentioned above. As the virus has spread worldwide, misleading and false information has also spread with it [13], leading to erroneous conclusions. Consequently, data quality plays a significant role in revealing trustworthy information through research, and falsifying clinical data can be a hazardous risk in clinical research discoveries. Blockchain can ensure data accuracy and quality through its service perspective and immunity, thus significantly contributing to pandemic data's quality and transfer transactions [12]. Studies have expected that the numbers of patients in several countries worldwide are considerably greater than what is officially reported [11], which can lead to numerous errors in making vital decisions; hence, maintaining the transparency of data during a pandemic is required for efficient decision-making.
Enrolled patients must also share all of their medical information, including past or current medical conditions. Since the lack of any generalized digital health record system, prior patient condition information is based on the personal statement, which can be inaccurate. For instance, in the recent Estonian experience, where 1.3 million residents profited from a Blockchain-enabled e-Health record system that automatically gives investigators access to the patient medical information recorded in the net, including their documents. This access would be assured until the patient gives its consent according to the smart contract; hence, this would lead to precise patient information. Moreover, ongoing logging of patients' health condition records on the Blockchain net provides transparency and trust between patients and information investigators.
3.3. Clinical trials of vaccine development for COVID-19
Controlling the virus’s spread necessitates the human body’s rapid immunizations against the virus by an active vaccine. At the time of writing this paper, many research institutes and laboratories worldwide are conducting clinical trials of several vaccine candidates. A few, such as Pfizer-BioNTech and Moderna, have already been verified. As C.D.C. reports, based on evidence from clinical trials, the Pfizer-BioNTech vaccine was 95% effective at avoiding laboratory-confirmed COVID-19 illness in people without previous infection.
Figure 6 displays the cumulative COVID-19 vaccination doses administered per 100 people. Currently, 68 different vaccines are being tested in clinical trials on humans, and 20 are in the final testing stages. Moreover, about 90 preclinical vaccines are under investigation in animals.
American Pfizer and the German company BioNTech presented preliminary news indicating that their coronavirus vaccine was over 90 percent effective on November 9. Over a month later, on December 11, the Food and Drug Administration granted the first emergency use authorization given by the United States to a coronavirus vaccine. Several countries have also given emergency authorization for Community, containing Argentina, Canada, Costa Rica, Chile, Ecuador, Kuwait, Jordan, Mexico, Panama, and Singapore. The European Union signed off on the vaccine on December 21. Meanwhile, Bahrain, Saudi Arabia, and Switzerland gave the vaccine full approval. Pfizer and BioNTech are expected to produce over 1.3 billion doses worldwide by the end of 2021.
The Moderna vaccine was the second lawful by the F.D.A., coming a week after Pfizer and BioNTech made the vaccine. Canada approved the vaccine on December 23. A few weeks later, the European Union, Israel, Switzerland, and the United Kingdom granted it emergency authorization. All Pfizer, BioNTech, and Moderna make their vaccines from mRNA. In recent years, companies have experienced mRNA vaccines for several diseases, but they have not yet to bring one to market.
3.4. Challenges in applying Blockchain to pandemic data collection
Despite Blockchain’s excessive potential in battling the COVID-19 pandemic, several challenges should be considered. In the following, some of the major challenges are outlined.
Developing a blockchain platform requires various skillsets ranging from security, technical and engineering, medical knowledge, and other related areas, which causes problems for companies in a shortfall in the expert workforce. Consequently, some companies train their employees in their training centers to fill blockchain-related job vacancies, while others may outsource. Yet, finding experts is still a critical challenge due to technology's novelty [14].
Moreover, as the number of transactions grows, the blockchain network will grow exponentially since all network nodes should store all validated data. This becomes a challenge as there is a limitation on the block size and time interval required for adding a new block. Existing blockchain platforms process a small number of transactions per second, which prevents large-scale blockchain platforms. Hence, scalability is also an obstacle in applying Blockchain to pandemic data.
Legal issues also need to be considered since the current pandemic’s most crucial concern is associated with the data being accessed and shared in the blockchain network. Several issues must be resolved by different parties, such as international health organizations. Data privacy is another critical challenge that is already discussed in detail [14].