FDA Clears Dual-Hormone Artificial Pancreas for Type 1 Diabetes

What Is the Dual-Hormone Artificial Pancreas?

The iLet Bionic Pancreas, developed by Beta Bionics, is a wearable automated insulin and glucagon delivery system that represents one of the most advanced closed-loop diabetes technologies in development. The system consists of three components: a continuous glucose monitor (CGM), a dual-chamber infusion pump capable of delivering both insulin and a stable glucagon analog (such as dasiglucagon), and an AI-driven control algorithm that processes glucose data at regular intervals to make autonomous dosing decisions.

What makes the dual-hormone approach fundamentally different from existing insulin-only automated systems is the addition of glucagon, the counter-regulatory hormone that raises blood glucose. In a healthy pancreas, alpha cells release glucagon when blood sugar drops too low, while beta cells release insulin when it rises too high. Current insulin pump systems can only reduce glucose by delivering insulin — they have no mechanism to actively raise glucose when it trends low, relying instead on suspending insulin delivery and hoping the patient eats. A dual-hormone system can deliver micro-doses of glucagon to actively prevent and treat hypoglycemia, providing a safety net that insulin-only systems cannot match.

The iLet system was first cleared by the FDA in May 2023 as an insulin-only automated system. Even in that configuration, the system requires remarkably little user input. At setup, the patient enters only their body weight — the algorithm self-adapts to individual insulin requirements over the first few days of use. No carb counting, insulin-to-carb ratios, basal rate programming, or correction factors are needed. The user simply initiates a meal announcement (choosing from 'usual,' 'more,' or 'less' categories) and the system handles the rest. This dramatically simplifies diabetes management, reducing the estimated hundreds of daily decisions that people with Type 1 diabetes typically make to manage their condition.

How Well Does the Dual-Hormone System Control Blood Sugar?

Clinical trials of dual-hormone artificial pancreas systems, including studies led by researchers such as Dr. Steven Russell at Massachusetts General Hospital and Dr. Ahmad Haidar at McGill University, have consistently demonstrated improved glycemic control compared to both insulin-only pumps and standard therapy. In a landmark study published in The Lancet Diabetes & Endocrinology, Haidar and colleagues compared dual-hormone artificial pancreas, single-hormone artificial pancreas, and conventional insulin pump therapy, finding that the dual-hormone approach provided superior glucose control with less hypoglycemia.

Across multiple clinical studies, dual-hormone systems have achieved mean time-in-range (TIR) values in the range of 75–85%, compared to approximately 60–70% with standard insulin pump therapy. To put this in perspective, international consensus guidelines recommend a target of greater than 70% TIR, and each 5-percentage-point increase in TIR has been associated with clinically meaningful reductions in the risk of diabetic complications, according to recommendations published in Diabetes Care by Battelino and colleagues.

The most impressive results from dual-hormone systems have been in hypoglycemia prevention. By delivering micro-doses of glucagon to intercept falling glucose before it reaches dangerous levels, these systems have demonstrated substantial reductions in both time below range (<70 mg/dL) and severe hypoglycemia events compared to standard therapy. This reduction in hypoglycemia risk is particularly important for children, elderly patients, and those with hypoglycemia unawareness — populations that face the highest risk from dangerously low blood sugar episodes. The addition of glucagon provides an active rescue mechanism that insulin-only systems simply cannot replicate.

Who Can Benefit from the Dual-Hormone Artificial Pancreas?

Several patient populations stand to benefit disproportionately from dual-hormone technology. Patients with hypoglycemia unawareness — who cannot feel when their blood sugar drops dangerously low — face the highest risk of severe hypoglycemic events and have the most to gain from a system that can automatically deliver glucagon to prevent them.

Young children with Type 1 diabetes present unique management challenges: unpredictable eating patterns, high physical activity levels, difficulty communicating symptoms, and the need for caregivers (parents, school nurses) to make complex dosing decisions. The iLet system's minimal user input requirement and automated glucagon safety net could transform the experience for these families. Pediatric subgroups in closed-loop studies have generally shown improvements in time-in-range with very low rates of severe hypoglycemia.

The device is also expected to benefit the large population of Type 1 diabetes patients who remain on multiple daily injection (MDI) therapy because they find existing pump systems too complicated. According to diabetes technology surveys, a substantial proportion of people with Type 1 diabetes in the US do not use insulin pump therapy, often citing complexity, alarm fatigue, and the cognitive burden of continuous management decisions. The iLet system's weight-only initialization and minimal daily interaction could appeal to many of these patients. Additionally, endocrinologists may be able to offer technology to patients who were previously considered unsuitable for pump therapy due to numeracy challenges, cognitive impairment, or limited diabetes education.

What Are the Limitations and Future Developments?

Despite its breakthrough potential, dual-hormone artificial pancreas technology has practical limitations. The system requires two separate infusion sites — one for insulin and one for glucagon — which doubles the number of site insertions and increases the body surface area needed for device wear. Glucagon stability, even with improved analogs like dasiglucagon, still requires cartridge replacement approximately every 3 days to ensure potency. The dual-chamber device is also somewhat larger than single-hormone insulin pumps.

Cost and insurance coverage represent significant access barriers. Dual-hormone systems are expected to cost substantially more than insulin-only pump therapy due to the additional glucagon supply and more complex hardware. Manufacturers will need to demonstrate cost offsets through reduced emergency department visits, hospitalizations for severe hypoglycemia, and long-term complications to secure favorable insurance coverage.

Several next-generation advances are under investigation. Researchers are working on single-device formulations that would co-deliver insulin and glucagon through a single infusion site using dual-lumen catheters. Research into ultra-stable glucagon formulations that maintain potency for longer periods would reduce the frequency of cartridge changes. Longer-term, the integration of additional sensors (accelerometers for exercise detection, meal sensors) and more advanced AI algorithms could further improve performance. The concept of a 'fully closed loop' requiring zero user input — not even meal announcements — is being explored in research studies and may become achievable as the technology matures.