What’s the difference between centralized and decentralized clinical trials?

When we talk about clinical trials, two branches of this process often come up in conversation: centralized and decentralized. If you’re not too familiar with the stages of drug development, the difference between these two concepts might not be immediately clear to you. In this blog post, we’ll explore how these two approaches differ, as well as the positive and negative aspects of both.

First things first: a centralized trial is, by definition, a trial which involves monitoring of the trial participant in a central location, such a single lab or testing facility. These trials are widely used across the pharmaceutical industry and have a smaller scope of patient recruitment, with evaluations normally carried out face-to-face by one specific researcher representing the organisation.

Decentralized trials, on the other hand, are described by the Clinical Trial Transformation Initiative as trials which are “executed through telemedicine and mobile/local healthcare providers, using processes and technologies differing from the traditional clinical trial model”. Essentially, these types of clinical trial do not require the trial participant to necessarily be present at the central study site for an in-person evaluation, with observations conducted at regional or local facilities.

Centralized trials might reasonably be seen as the more traditional model of research, with decentralized trials acting as a more modern phenomenon. Both have their pros and cons, with many researchers preferring the perceived higher levels of control that come with centralized trials. Additionally, centralized trials might require less organization in general, with researchers avoiding the extra administrative work that comes with liaising with a number of different facilities. 

However, centralized trials can often struggle with the participant recruitment process, as many patients either can’t or simply don’t want to travel long distances to research facilities. As a result, the pool of potential participants is limited – something clinical trials very much want to avoid if possible. If a trial takes longer than expected due to smaller participant numbers than anticipated, research and development teams are at risk of losing funding, with many clinical trials being forced to stop altogether once sponsors drop out.

Conversely, decentralized trials offer potential participants the flexibility to travel to a location that’s in reasonable distance of their home, saving time, money, and effort. In addition to this, another benefit for the trial practitioners is a boom in the number of patients who are able to take part, thus increasing the sample size and, as a result, the reliability and accuracy of the data produced, leading to a better scope of research. This patient-focused approach provides clinicians with the opportunity to communicate and check in with the trial participants more regularly than a centralized trial might allow, meaning that data collection can be performed in a higher temporal resolution. Alternatively, some decentralized trials are embracing the possibility of patient-generated data collection, relying on participants to input their information remotely – via an app, for example.

Whilst a decentralized approach might seem to be a win-win situation, not every trial is suitable for this model. Expanding the trial to several different locations means a well-oiled team is crucial in ensuring consistency across the spectrum, ensuring trials are carried out in exactly the same way in each facility. Additionally, some participants might not be well-versed in technology, and may struggle with using an app for the first time if the app simply does not offer a user-friendly experience – perhaps its UI is poorly designed or executed, or there are bugs that need to be fixed. However, the use of app-based data collection means that studies do not need to be paused when external factors - such as an ongoing viral pandemic - limit the participant’s ability to travel to their local facility, meaning that trials can in theory still finish on time, avoiding lengthy and costly delays.

Decentralized clinical trials are still relatively new and, as will any development of this nature, will require a few tweaks before they can fully reach their potential. That being said, there are a huge number of benefits to this approach. We will always need centralized trials to some extent, but the participant-centered approach to decentralized clinical trials makes economic sense. Technology offers countless opportunities for the pharmaceutical industry, and decentralizing the clinical trial process is one of the most exciting.