Type 1 diabetes is estimated to affect around 1.25 million children and adults in the United States.
The condition arises when the beta cells of the pancreas stop producing insulin – the hormone that is responsible for removing glucose from the blood and transporting it to cells, where it is used for energy. Without insulin, blood glucose levels become too high.
In order to control blood glucose levels, patients with type 1 diabetes require daily doses of insulin, either through injections or an insulin pump.
Injections remain the most common form of insulin administration; two daily injections are normally recommended for patients who have just been diagnosed with type 1 diabetes, normally increasing to three or four over time.
Insulin pumps are a more advanced form of insulin delivery. They are devices that deliver a continuous dose of insulin 24 hours a day via a catheter that is inserted under the skin.
The problems with current insulin therapies
However, while mostly effective for blood glucose control in type 1 diabetes, current insulin delivery methods do not account for variability of insulin needs among patients with type 1 diabetes.
The amount of insulin a patient needs can vary from day to day, depending on their diet, physical activity levels, and – for women – changes in insulin sensitivity during menstruation.
According to report authors Drs. Roman Hovorka and Hood Thabit, of the University of Cambridge in the United Kingdom, this puts pressure on patients with type 1 diabetes to regularly measure their blood glucose levels to make sure they are not too high or low, and to ensure the correct amount of insulin is administered.
Such pressure can fuel poor blood glucose control for patients with type 1 diabetes, which puts them at greater risk of complications, including heart disease and vision problems.
Numerous studies have investigated beta cell islet transplantation as a way of overcoming such issues, in which a patient’s abnormal insulin-producing cells will be replaced with those from a healthy donor, restoring insulin production.
While such a treatment has been hailed a “breakthrough” for type 1 diabetes, it does require major surgery and the subsequent use of immunosuppressant medication.
In the new report, published in the journal Diabetologia, Drs. Hovorka and Thabit explain how an artificial pancreas could offer a less invasive and more effective treatment for type 1 diabetes; it could eliminate the need for patients to continuously measure blood glucose and deliver insulin only when needed.
What is more, this revolutionary technology might finally be within reach.
Testing the efficacy of a ‘closed-loop’ system
There are various forms of an artificial pancreas that are currently being tested in clinical trials.
Earlier this year, for example, researchers from the University of Virginia School of Medicine revealed the development of an artificial pancreas that can be controlled by a smartphone; there are currently two clinical trials testing the safety and efficacy of the device.
Despite differing in design, each artificial pancreas works on the same basis, incorporating a “closed-loop” system.
Put simply, the closed-loop system consists of continuous glucose monitoring, an insulin pump, and algorithms that control when insulin should be delivered.
In their report, Drs. Hovorka and Thabit point out that, to date, such technology has performed well in clinical trials, in which they have been tested in a variety of settings. These include controlled laboratory studies, diabetes camps, and outpatient settings.
The authors point to one study, in which 24 participants with type 1 diabetes used a closed-loop artificial pancreas in a home setting for 6 weeks. In this trial, researchers monitored how the artificial pancreas affected participants’ blood glucose levels overnight – a period when such levels are more likely to fall, a state known as hypoglycemia.
Compared with a conventional insulin pump therapy, the researchers found that the amount of time participants spent in a hypoglycemic state reduced by twofold with the artificial pancreas. Additionally, subjects were 11 percent more likely to reach the optimal blood glucose range.
Drs. Hovorka and Thabit note:
“In trials to date, users have been positive about how use of an artificial pancreas gives them ‘time off’ or a ‘holiday’ from their diabetes management, since the system is managing their blood sugar effectively without the need for constant monitoring by the user.”
Artificial pancreas could be FDA-approved next year
While studies have demonstrated that the artificial pancreas may be more effective than current insulin therapies, clinical trials are ongoing, with the aim of testing the long-term safety and efficacy of the devices.
Whether these devices will be approved for clinical use depends on the results of these trials, but Drs. Hovorka and Thabit believe that the future is bright for the artificial pancreas.
The U.S. Food and Drug Administration (FDA) are in the process of reviewing one artificial pancreas, and the authors note that it is possible the device will be approved as early as next year.
Furthermore, the National Institute of Health Research (NIHR) in the U.K. have announced that closed-loop systems could reach clinical use by the end of 2018.
“This will largely be dependent upon regulatory approvals (but there is a reassuring attitude of regulatory agencies such as the U.S. FDA towards these therapies) and whether infrastructures and support are in place for the healthcare professionals providing clinical care,” say the authors.
“Structured education will also need to continue to augment efficacy and safety of this therapy,” they add.
Artificial pancreas ‘a viable alternative’ to insulin pumps, injections
However, there are still many obstacles to overcome before patients with type 1 diabetes can reap the benefits of an artificial pancreas.
For example, the authors point out that closed-system technology may not always be able to deliver insulin to the patient fast enough. Studies have shown that even the delivery of fast-acting insulin may take up to 2 hours to bring blood glucose to optimal levels, which may not be quick enough in certain circumstances, such as after vigorous physical activity.
What is more, Drs. Hovorka and Thabit note that closed-loop devices may be “vulnerable to cybersecurity threats such as interference with wireless protocols and unauthorized data retrieval,” making the “implementation of secure communications protocols a must.”
Still, the authors are confident that these are issues that can be resolved, and they believe the artificial pancreas is well on the way to providing more effective insulin therapy for people with type 1 diabetes:
“Significant milestones moving the artificial pancreas from laboratory to free-living unsupervised home settings have been achieved in the past decade. Through inter-disciplinary collaboration, teams worldwide have accelerated progress and real-world closed-loop applications have been demonstrated.
Given the challenges of beta cell transplantation, closed-loop technologies are, with continuing innovation potential, destined to provide a viable alternative for existing insulin pump therapy and multiple daily insulin injections.”