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External Control Arms in Clinical Trials | MIT Technology Review & Medidata Solutions

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Exploring External Control Arms in Clinical Trials

Written in partnership with MIT Technology Review 


Clinical trials have never been more in the public eye than in the past year, as the world watched the development of vaccines against COVID-19. Discussions of study phases, efficacy, and side effects dominated the news. The most distinctive feature of the vaccine trials was their speed. Because the vaccines are meant for universal distribution, the study population was, essentially, everyone. That unique feature meant that recruiting enough people for the vaccine trials was not the obstacle that it commonly is. 


“One of the most difficult parts of my job is enrolling patients into studies,” says Nicholas Borys, chief medical officer for biotechnology company Celsion, which develops next-generation chemotherapy and immunotherapy agents for liver and ovarian cancers, and certain types of brain tumors. Borys estimates that fewer than 10% of cancer patients are enrolled in clinical trials. “If we could get that up to 20% or 30%, we probably could have had several cancers conquered by now.” 


The path from study design to approval is long, winding, and expensive. Today, researchers are using artificial intelligence and advanced data analytics to speed up the process, reduce costs, and get effective treatments more swiftly to those who need them. And they’re tapping into an underused but rapidly growing resource: Data on patients from past trials. 

This five-part blog series explores the world of “external control arms,” which reuse data on control-group patients from past clinical trials instead of recruiting patients for a traditional control arm. 


Why Use an External Control Arm? 

External control arms can make clinical trials less expensive by reducing the number of patients that need active management. Read the full blog here 


How External Control Arms Work 

To build an external control arm, researchers mine a database of past clinical trials to find control subjects who are close matches to the patients in the treatment arm. Read the full blog here. 


New Insights from RWD 

Real-world data has the potential to further refine the clinical trial process, make it faster, cheaper, and more accurate, and extend it to post-market surveillance to verify whether new medications and procedures fulfill the promise of their clinical trials. Read the full blog here. 


The Quest for FDA Approval 

How does the US Food and Drug Administration, the ultimate judge of clinical trial validity, feel about external control arms? Favorable, though appropriately cautious. Read the full blog here 


What’s Next For External Controls? 

External control arms have potential applications after regulatory approval of a product as well. Read the full blog here 

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