Beta Bionics iLet Bionic Pancreas

The iLet Bionic Pancreas is a tubed, rechargeable insulin pump whose defining feature is its software, not its hardware: it is the first system designed to be set up with only your body weight — no basal rates, no insulin-to-carb ratios, and no correction factors.¹ Because the dosing logic is so different from every other pump, the iLet is best understood and ranked as its own delivery device.

Form factor & wear. It is a durable, tubed pump (not a patch), weighing about 110 g with a full cartridge, with a colour touchscreen and an IPX8 water-resistance rating (immersion to ~12 feet for 30 minutes).² Insulin sits in an ~180-unit fillable glass cartridge, or you can use a 160-unit (1.6 mL) prefilled Fiasp cartridge.²¹ It connects to the body through a standard tubed infusion set; only 6 mm cannulas are offered, in a Teflon set worn up to 3 days or a steel set worn up to 2 days.¹

Reliability & occlusion detection. A dedicated occlusion alarm suspends insulin when flow is blocked and must be acknowledged before dosing resumes, alongside low-insulin and "insulin out" alarms.¹ In the pivotal trial, infusion-set failures occurred at roughly 1.3% per day — essentially the same rate as the well-established Tandem Control-IQ pump.¹ The control algorithm runs every 5 minutes and will fully suspend basal insulin for low or rapidly falling glucose.¹

Which CGMs, algorithms & DIY it works with. The iLet pairs with Dexcom G6, Dexcom G7, and the Abbott FreeStyle Libre 3 Plus; the Dexcom sensors can be calibrated from the pump, the Libre cannot.¹³ Crucially, it is a closed ecosystem: it always runs only its own FDA-cleared dosing software and cannot be used with DIY/open-source systems or any third-party algorithm.⁴¹ It is cleared for rapid-acting U-100 insulin only — Humalog (lispro), NovoLog (aspart), and Fiasp.¹

How dosing works. Three algorithms run in parallel — an adaptive basal algorithm, a model-predictive-control bolus algorithm, and a separate meal-dose algorithm — and they adapt continuously to your needs.¹ Instead of counting carbs, you announce a meal as "usual for me," "more," or "less," separately for breakfast, lunch, and dinner.¹ The only adjustable setting is a glucose target ("Usual" 120, "Lower" 110, or "Higher" 130 mg/dL).¹

Phone bolusing. There is none. The companion smartphone app is view-only — it mirrors glucose, trend, and alerts — and every meal announcement or dose is entered on the pump's own touchscreen.⁵

Evidence. Across multicentre randomised trials in adults and in youth 6–17, the iLet lowered HbA1c by about 0.5% and raised time-in-range by roughly 2.4–3.4 hours per day versus standard care, without increasing hypoglycaemia, with the largest gains in people starting at high HbA1c.⁶⁷⁸ It also improved control in cystic-fibrosis-related diabetes.⁹

Access & cost (US). The iLet is FDA-cleared and US-only.⁴ It is covered under commercial, Medicare and Medicaid plans, and major pharmacy-benefit managers (Express Scripts, Prime Therapeutics) have added it to national formularies, which can sharply reduce the up-front pump cost.¹⁰

What's coming. Beta Bionics is developing "Bionic Circle," a companion app intended to add remote monitoring/sharing, and continues to expand CGM compatibility (Libre 3 Plus support was a recent addition).¹¹ The longer-term roadmap returns to the project's origin: a bihormonal version that doses both insulin and glucagon, which the iLet hardware was originally designed to support.⁹

References

1. Beta Bionics. iLet Bionic Pancreas System: Guide for Health Care Providers (LA000079_F). Beta Bionics (2025). https://www.betabionics.com/wp-content/uploads/LA000079_F-iLet-Bionic-Pancreas-System-HCP-Guide-Clean-r2.pdf ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰ ↩¹¹ ↩¹²

2. American Diabetes Association. iLet Bionic Pancreas System — Consumer Guide. ADA Consumer Guide (2024). https://consumerguide.diabetes.org/products/insulin-pumps/ilet-bionic-pancreas-system ↩ ↩²

3. Dexcom. iLet (Beta Bionics) and Dexcom G7 FAQs. Dexcom (2024). https://www.dexcom.com/en-us/faqs/ilet-beta-bionics-dexcom-g7-faqs ↩

4. U.S. FDA. iLet ACE Pump and iLet Dosing Decision Software — 510(k) K223846 Summary. FDA (2023). https://www.accessdata.fda.gov/cdrh_docs/pdf22/K223846.pdf ↩ ↩²

5. Beta Bionics. Compatibility for iLet and Bionic Circle Apps. Beta Bionics Support (2025). https://www.betabionics.com/support/compatibility/ ↩

6. Kruger D, et al. A Multicenter Randomized Trial Evaluating the Insulin-Only Configuration of the Bionic Pancreas in Adults with Type 1 Diabetes. Diabetes Technol Ther (2022). https://pmc.ncbi.nlm.nih.gov/articles/PMC9634987/ ↩

7. Messer LH, et al. Positive Impact of the Bionic Pancreas on Diabetes Control in Youth 6–17 Years Old with Type 1 Diabetes. Diabetes Technol Ther (2022). https://pmc.ncbi.nlm.nih.gov/articles/PMC9529304/ ↩

8. Beck RW, et al. A Multicenter Randomized Trial Evaluating Fast-Acting Insulin Aspart in the Bionic Pancreas in Adults with Type 1 Diabetes. Diabetes Technol Ther (2022). https://pmc.ncbi.nlm.nih.gov/articles/PMC9529301/ ↩

9. Sherwood JS, et al. Randomized Trial of the Insulin-Only iLet Bionic Pancreas for the Treatment of Cystic Fibrosis-Related Diabetes. Diabetes Care (2024). https://pmc.ncbi.nlm.nih.gov/articles/PMC10733649/ ↩ ↩²

10. Hibbs N. Beta Bionics earns pharmacy benefit win for bionic pancreas. Drug Delivery Business News (2025). https://www.drugdeliverybusiness.com/beta-bionics-pharmacy-benefit-bionic-pancreas/ ↩

11. Beta Bionics. Compatibility & supported devices. Beta Bionics Support (2025). https://www.betabionics.com/support/compatibility/ ↩