FDA Issues Warning on Do-It-Yourself Artificial Pancreas

The FDA on Friday issued its first-ever warning about do-it-yourself (DIY) artificial pancreas systems after a patient who used one suffered an accidental insulin overdose. The incident, and the FDA’s action, prompted a statement on Twitter from several well-known developers.

DIY systems combine FDA-approved components, including insulin pumps and continuous glucose monitors (CGM), with open source software to deliver continuous doses of insulin. It is estimated that the systems have attracted thousands of users who either have type 1 diabetes (T1D) or who are parents of children with T1D.

“The FDA is concerned about people with diabetes using unauthorized devices for diabetes management used alone or along with authorized devices,” the agency's statement read. The FDA received a report of a “serious adverse event,” of a patient using a DIY system that included an “unauthorized algorithm.”

“This unauthorized system resulted in an insulin overdose requiring medical intervention. These devices were not designed to be used together and were combined in a way that had not been thoroughly tested for compatibility,” the statement continued, adding that it was unclear exactly how the malfunction occurred.

“When patients combine devices that are not intended for use with other devices, or when patients use any unauthorized devices, new risks are introduced that the FDA has not evaluated for safety or effectiveness,” the statement said. “Patient use of unauthorized diabetes management devices, alone or along with other devices, could result in inaccurate glucose level readings or unsafe insulin dosing.”

The joint statement on Twitter from Open Artificial Pancreas (OpenAPS), Loop, and AndroidAPS, 3 popular DIY developers, said the incident occurred outside the United States and the patient had recovered. Both the joint statement and messages Friday from other DIY advocates encouraged transparency. “We want you to report adverse events on DIY systems, if and when they occur,” the statement said.

The DIY movement is roughly 5 years old; OpenAPS founders Dana Lewis and Scott Leibrand created the first system from an older-model insulin pump in December 2014. Another milestone came the following spring, when John Costik, whose son has T1D, presented the Nightscout Project at South by Southwest. Costik’s focus at that time was remote monitoring of his son’s glucose levels, a feature that manufacturers have since addressed. All were motivated by the limits of existing technology, a sentiment embodied in the hashtag #WeAreNotWaiting that unites users of various DIY artificial pancreas systems.

In 2016, FDA approved a hybrid closed loop system from Medtronic, and in March 2018 approved the Dexcom G6 integrated CGM system through a less burdensome regulatory pathway, one that anticipates the product will interact with other devices. In February 2019, the Tandem t:slim X2 interoperable insulin pump was approved through the de novo premarket review pathway. But people with T1D are still waiting for other highly anticipated systems, including the Bigfoot Biomedical smart pump, which will work with Abbott’s Freestyle Libre CGM.

Why do patients turn to DIY systems? Some are dissatisfied with current commercial options, and others must contend with payer coverage decisions that put new technologies out of reach. The T1D community has protested a partnership between UnitedHealthcare and Medtronic that transitioned adults in the health plan over to Medtronic products starting in 2016; in February, word came the healthcare giant will now do the same with pediatric patients.

Thus far, FDA has left DIY developers alone, as the products are not sold, and the open access software is available for free.

Friday’s statement said, “The FDA is aware of manufacturers marketing unauthorized diabetes management devices that use an algorithm to convert raw data from an FDA authorized glucose sensor to a glucose level displayed to the patient. The FDA has not evaluated the algorithm that these unauthorized devices use. The algorithm may return inaccurate glucose values.” No companies were named in the statement.