AT278 data published in peer-reviewed journal

• Findings support AT278's potential as first ultra-rapid U500 option for insulin resistance in people with type 2 diabetes requiring high-dose therapy, regardless of BMI
• Reinforces its potential to enable next-generation automated insulin delivery technologies

Cambridge, UK, 13 August 2026: Arecor Therapeutics plc (AIM: AREC), a clinical stage biotech company developing superior therapeutics that can reduce treatment burden and improve outcomes for people living with diabetes, obesity and other cardiometabolic diseases, announces the publication of clinical data from its AT278-104 study published in the peer-reviewed Diabetes, Obesity & Metabolism.

The study demonstrated that AT278, Arecor's investigational ultra-concentrated (500U/mL or U500) insulin aspart formulation, maintained its ultra-rapid pharmacokinetic (PK) and pharmacodynamic (PD) profile regardless of body mass index (BMI) levels, supporting its potential as the first ultra-rapid U500 insulin for people with insulin-resistant type 2 diabetes who require high-dose therapy.

This article marks the first time the complete study results have been published in a peer-reviewed scientific journal, following presentations at the annual meeting of the European Association for the Study of Diabetes (EASD) and the American Diabetes Association's (ADA) Scientific Sessions.

The published study, A New Highly Concentrated Insulin Aspart AT278 (500 U/mL) Demonstrates Ultra-Rapid Pharmacokinetic and Pharmacodynamic Properties in Type 2 Diabetes Regardless of BMI, evaluated the PK, PD and safety of AT278 (500U/mL) compared with standard concentration (U100; 100U/mL) insulin aspart and U500 human regular insulin (500U/mL). Key study findings include:

• AT278 exhibited a significantly faster insulin absorption than both standard U100 concentration insulin aspart and U500 human regular insulin.
• Faster absorption led to a significantly greater glucose-lowering effect within the first hour following administration.
• AT278 maintained its ultra-rapid onset characteristics independent of BMI, distinguishing it from standard insulin apart.
• Overall, insulin exposure and glucose-lowering activity remained comparable while maintaining a favourable safety profile.

Dr Jan Jezek, CSO of Arecor commented:

"The publication of the AT278-104 study in Diabetes, Obesity & Metabolism provides important peer-reviewed validation of our work advancing next-generation insulin formulations for people with high-dose insulin requirements. The study demonstrated that AT278 maintained its ultra-rapid PK and PD profiles in a high BMI type 2 diabetic patient population, addressing one of the longstanding challenges associated with concentrated insulin therapies.

"With obesity now affecting more than one billion people worldwide1 and insulin resistance continuing to increase globally, more people are developing type 2 diabetes. In many obese people with type 2 diabetes, severe insulin resistance results in high total daily insulin requirements. The US average daily insulin dose for this patient population is 100 units, making concentrated ultra-rapid-acting insulin an essential therapeutic option.

"We believe these findings support the potential for AT278 to become the first ultra-rapid U500 insulin for prandial use while also reinforcing the important role that advanced insulin formulations will play in enabling smaller, longer-wear fully automated insulin delivery systems that simplify diabetes management, reducing burden and improving outcomes."

[1] 1 NCD Risk Factor Collaboration (NCD-RisC), "Worldwide Trends in Underweight and Obesity From 1990 to 2022: A Pooled Analysis of 3663 Population-Representative Studies With 222 Million Children, Adolescents, and Adults," Lancet 403, no. 10431 (2024): 1027-1050.

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