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Sequel twiist

Sequel Med Tech (device developed by DEKA Research & Development; algorithm powered by Tidepool Loop)

A tubed hybrid closed-loop system built on the FDA-cleared Tidepool Loop algorithm (a commercialized descendant of the open-source Loop). A round, under-2-oz pump uses acoustic "iiSure" sensing to measure the volume of every insulin micro-dose for occlusion detection up to nine times faster than other systems. Controlled from an iPhone and Apple Watch; works with FreeStyle Libre 3 Plus or the one-year implantable Eversense 365 CGM.

Available nowStrong evidencehybrid-closed-looptubedphone-controlOfficial site ↗

The scorecard

Time in range75

Type 1 only: twiist runs the Tidepool Loop algorithm, whose real-world type 1 cohorts achieve roughly 73–82% time-in-range (n up to 558). twiist's own pivotal trial was in type 2 diabetes and is excluded; no dedicated type 1 pivotal RCT exists for the device.

Hypo protection78

Predictive low-glucose suspend plus a high-resolution dosing engine; in the real-world type 1 Loop cohort time below 70 mg/dL held around 2.8% (below 54 mg/dL at 0.36%) and severe-hypo events fell sharply.

Automation level64

Hybrid loop: adjusts basal and gives automatic correction boluses every five minutes, but meals must still be announced with carb counts. No unannounced-meal handling.

Average glucose74

In real-world type 1 Loop cohorts HbA1c averaged ~6.2–6.5% with median glucose ~130 mg/dL; the type 2 pivotal HbA1c drop is not used to score type 1 performance.

Low variability68

Five-minute micro-dosing smooths swings, but as a hybrid loop it inherits the variability ceiling set by injected-insulin speed and large unannounced meals.

Exercise handling70

A Workout Preset raises the target temporarily across a wide band (as high as 250 mg/dL) to reduce exercise lows; still requires user activation.

Customizability80

Highly tunable: correction-range targets from 87-180 mg/dL across up to 48 daily segments, plus carb-absorption-time entry, exceeding most commercial AID systems.

Access & cost56

US-only, distributed through the pharmacy channel; not yet available outside the United States and requires a compatible iPhone (iOS 18+).

Freedom (form factor)62

A round pump under 2 oz controlled from an iPhone and Apple Watch — light and small, but tubed with an infusion set.

Glycemic criteria are scored on the levels actually achieved in large real-world Type 1 diabetes cohorts — not the headline improvement over a trial's baseline (an improvement that looks bigger when the starting population was doing poorly). Type 2 diabetes trial data is never used to score a Type 1 system; where only improvement data exists, it informs the rationale, not the score. Freedom captures form factor and wearability, so a tubeless system is rewarded for the mobility a tubed one can't match.

The full picture

The Sequel twiist is a tubed hybrid closed-loop ("artificial pancreas") system that became available in the United States on 7 July 2025.1 It pairs three parts: a pump, a continuous glucose monitor (CGM), and a control algorithm. The pump is a round device that weighs less than 2 oz and holds a 300-unit insulin cartridge; it is the first automated insulin delivery (AID) system controllable from both an iPhone (iOS 18+) and an Apple Watch.2 The "brain" is the twiist Loop algorithm, a commercialized version of the patient-built open-source Loop, powered by Tidepool; the device was developed by DEKA Research & Development (founded by Segway inventor Dean Kamen) and received FDA 510(k) clearance on 18 March 2024.3

What makes it different. A technology called iiSure uses sound waves to measure the volume of every insulin micro-dose at four checkpoints as it is delivered, allowing the pump to detect blockages (occlusions) up to nine times faster than other AID systems.4

Automation level. twiist is a hybrid closed loop: every five minutes it can automatically increase, decrease, or suspend basal insulin and deliver automatic correction boluses based on CGM readings and predicted glucose.2 You still announce meals by entering carbohydrates (with emoji shortcuts for fast vs. slow carbs); it does not silently absorb unannounced meals.2 Targets are unusually customizable — a correction range from 87–180 mg/dL across up to 48 daily segments.2

Exercise. A Workout Preset temporarily raises the glucose target (as high as 250 mg/dL) to reduce activity-related lows.2

Trial outcomes. twiist's algorithm rests on a deep evidence base for Loop. In an independent comparison, people using open-source Loop-type systems averaged 81.7% time in range (TIR), 2.2% time below range, a median glucose of 130 mg/dL, and an HbA1c of 6.2%.5 Sequel's own multi-center pivotal AID trial — run in 307 insulin-treated adults over 13 weeks — raised TIR (70–180 mg/dL) from 57% to 73% (a 16-point gain), cut time below 70 mg/dL from 0.66% to 0.36%, lowered HbA1c by 0.7 points, and reported no severe hypoglycemia.6 (That pivotal trial was in type 2 diabetes; a dedicated twiist type 1 pivotal RCT has not yet been published — FDA clearance came through the interoperable-controller pathway rather than a new T1D trial.)3 Early type 1 use is documented, including a published case of managing pregnancy with the system.7

Ages & access. Cleared for type 1 diabetes, ages 6 and up.3 It is sold in the US through the pharmacy channel and works with the FreeStyle Libre 3 Plus sensor or the implantable Eversense 365 CGM.2

What's coming. In February 2026 Sequel and Senseonics launched the twiist + Eversense 365 combination nationwide — the first AID system to pair with a one-year implantable CGM, cutting sensor changes to once a year.8 An Android app is in development,2 and in June 2026 Sequel presented pivotal data extending twiist to insulin-treated type 2 diabetes, signaling a planned label expansion.6

References

  1. Sequel Med Tech / Senseonics. Launch of twiist with Eversense 365 (notes US availability of twiist from July 7, 2025). GlobeNewswire (2026). https://www.globenewswire.com/news-release/2026/02/19/3241021/0/en/Sequel-Med-Tech-and-Senseonics-Launch-Transformative-Combination-of-twiist-and-Eversense-365.html ↩

  2. Sequel Med Tech. twiist Frequently Asked Questions (pump weight <2 oz, 300-unit cartridge, iPhone/Apple Watch control, carb entry, automatic correction, 87–180 mg/dL correction range, 48 segments, Workout Preset, compatible CGMs, pharmacy availability, Android in development). twiist.com (2026). https://www.twiist.com/faq ↩ ↩2 ↩3 ↩4 ↩5 ↩6 ↩7

  3. Sequel Med Tech / DEKA. twiist Automated Insulin Delivery System Receives FDA 510(k) Clearance (cleared March 18, 2024; ages 6+ type 1 diabetes; Tidepool Loop; directly measures volume and flow of each micro-dose). BioSpace (2024). https://www.biospace.com/sequel-s-twiist-automated-insulin-delivery-system-receives-fda-510-k-clearance ↩ ↩2 ↩3

  4. Sequel Med Tech. iiSure Technology (acoustic measurement of insulin volume at four checkpoints; occlusion detection up to nine times faster). twiist.com (2026). https://www.twiist.com/iisure-technology ↩

  5. Schütz A, Rami-Merhar B, Schütz-Fuhrmann I, et al. Retrospective Comparison of Commercially Available Automated Insulin Delivery With Open-Source Automated Insulin Delivery Systems in Type 1 Diabetes. J Diabetes Sci Technol (2024). PMID 38366626. https://pubmed.ncbi.nlm.nih.gov/38366626/ ↩

  6. Sequel Med Tech. Pivotal Trial of the twiist AID System in Adults with Insulin-Treated Type 2 Diabetes, ADA 86th Scientific Sessions (307 adults, 30 sites, 13 weeks; TIR 57%→73%; TBR<70 0.66%→0.36%; HbA1c −0.7; no severe hypoglycemia). GlobeNewswire (2026). https://www.globenewswire.com/news-release/2026/06/08/3307938/0/en/Sequel-Presents-Pivotal-Trial-of-the-twiist-Automated-Insulin-Delivery-System-in-Adults-with-Insulin-Treated-Type-2-Diabetes-at-the-ADA-86th-Scientific-Sessions.html ↩ ↩2

  7. Bhasin K, Bowdler M, Scifres CM, Cleary EM, Shah VN. Management of Pregnancy in Type 1 Diabetes Using a Novel Automated Insulin Delivery System. J Diabetes Sci Technol (2026). PMID 42175898. https://pubmed.ncbi.nlm.nih.gov/42175898/ ↩

  8. Sequel Med Tech / Senseonics. Launch of the twiist + Eversense 365 combination — first AID system compatible with a one-year implantable CGM. GlobeNewswire (2026). https://www.globenewswire.com/news-release/2026/02/19/3241021/0/en/Sequel-Med-Tech-and-Senseonics-Launch-Transformative-Combination-of-twiist-and-Eversense-365.html ↩

What's next for this

  • →Nationwide launch of twiist + Eversense 365 combination — first AID to pair with a one-year implantable CGM · February 2026
  • →Android app in development
  • →Label expansion to insulin-treated type 2 diabetes (pivotal data presented June 2026)