Arecor Therapeutics has partnered with Sequel Med Tech to pair its ultra-concentrated, rapid-acting insulin, AT278, with Sequel’s twiist automated insulin delivery (AID) system powered by Tidepool.

The collaboration focuses on people who require higher insulin doses including people with type 1 and type 2 diabetes, and prefer smaller, longer-wear insulin pumps. Both companies plan to contribute $1.3 million to move the project into Phase 2 clinical trials in 2026.

AT278 is a 500U/mL ultra-rapid and ultra-concentrated insulin in development. Once approved, it could become the first of its kind for next-generation pump systems. Arecor previously worked with Medtronic on a similar insulin initiative, continuing its effort to expand options for insulin delivery.

Sequel’s twiist pump, launched in summer 2025, uses acoustic sensing to measure every microdose of insulin in real time. That precision makes it well suited for use with concentrated insulins like AT278. The twiist system has already drawn attention for its design and ecosystem. It integrates with the Libre 3 Plus continous glucose monitor (CGM) and soon, the Eversense 365, and includes smartwatch bolusing, and advanced occlusion detection. You can learn more about twiist here.

Sequel has also said its working on a proprietary infusion set. If that set lasts seven days, I can’t help but wonder if a more concentrated insulin would allow for a twiist cartridge to last the same seven days as its infusion set. A seven day set would make sense given Medtronic’s Extended Infusion Set and Tandem’s FDA cleared SteadiSet that lasts a full week.

If Sequel unlocks Arecor’s insulin which is five times more concentrated than the insulins pumps use today, it could unlock the ability to install smaller insulin champers and therefore smaller devices.

Development and regulatory work for the AT278-twiist program will begin immediately, with an IND submission expected in 2026. If cleared, clinical studies could follow later in the year.

For a closer look at how the twiist performs in everyday life, watch our recent interview with twiist users about their experience using it for a month. Our editor, Justin Eastzer is testing it right now and will be documenting his experience using it on here, so stay tuned.

Disclaimer: Diabetech content is not medical advice—it’s for educational purposes only. Always consult with a physician before making changes to your healthcare.