TouchENDOCRINOLOGY coverage from EASD 2025:
At the EASD 2025 congress (Vienna, Austria; 15–19 September), Dr Pieter Gillard presented results from the 13-week extension of the RADIANT study (NCT05923827), which investigated the sustained efficacy and safety of the Omnipod 5 Automated Insulin Delivery (AID) system in people with type 1 diabetes. The findings provide further evidence that direct transition from multiple daily injections to a tubeless AID system can improve glycaemic outcomes without increasing hypoglycaemia risk. In this interview, Dr Gillard discusses the study design, key results, and the potential impact of Omnipod 5 on everyday clinical practice.
Q. What did the RADIANT study teach us about the efficacy and safety of the Omnipod 5 AID system in type 1 diabetes, and what did you hope to explore in this 13-week extension phase?
The original RADIANT trial was designed because many people using multiple daily injections (MDI) alongside continuous glucose monitoring (CGM) still struggle to reach recommended clinical targets, such as an HbA1c below 7% or more than 70% time in range. We wanted to see whether people who were not achieving targets on MDI+CGM could transition directly to an AID system, in this case, the tubeless Omnipod 5, and achieve better outcomes without added risk.
The trial was a classical randomized controlled design with two arms. Participants were either transitioned directly from MDI to Omnipod 5 or remained on MDI+CGM. We showed that direct transition led to significant improvements: a 0.8% HbA1c reduction after 13 weeks, more than a 20% increase in time in range, equivalent to over 5 additional hours per day, and importantly, no increase in hypoglycaemia. No episodes of severe hypoglycaemia or diabetic ketoacidosis (DKA) were reported during the study.
The extension phase had two goals: first, to see whether participants in the control arm who transitioned to Omnipod 5 would experience the same improvements; and second, to confirm whether the benefits seen in the intervention arm could be maintained over 26 weeks.
Q. What were the aims, design and eligibility criteria of the extension study, and how was the transition from multiple daily injections to AID managed?
In the extension, the control group crossed over to Omnipod 5 (the MDI–AID group), while those already using Omnipod 5 continued for another 13 weeks (the AID–AID group). Almost everyone who completed the randomized phase (>99%) chose to enter the extension, which in itself suggests patients were keen to use the system.
Eligibility criteria for the original RCT required type 1 diabetes for at least 1 year, being pump naïve, having used CGM for several months, and an HbA1c above 7.5% (with a mean of 8.1% at baseline in actual study).
One unique aspect of the study was the approach to initiation. Traditionally, in some centres (such as in Belgium) we admit patients to hospital for several days when starting on an insulin pump. In RADIANT, participants began Omnipod 5 as outpatients: they came to clinic, received education, and left a few hours later with their first pod already in automated mode. Both patients and clinical teams found this ambulatory start straightforward and well accepted, and it has influenced how we now implement AID in clinical practice.
Q. What were the primary and secondary endpoints in the extension phase, and how were these achieved in terms of HbA1c, time in range and hypoglycaemia?
The primary endpoint was HbA1c, with key secondary endpoints including time in range and hypoglycaemia.
In the MDI–AID group, HbA1c improved from 8.0% to 7.3% over 13 weeks. This 0.7% reduction is clinically meaningful and was accompanied by a 22% increase in time in range again, equivalent to more than 5 additional hours per day in target. These improvements were mainly due to reduced hyperglycaemia, without an increase in hypoglycaemia. Time below range remained low and within recommended targets.
Safety outcomes were also reassuring there was just one episode of severe hypoglycaemia in the AID–AID group and one case of DKA in the MDI–AID group across nearly 200 participants followed for 6 months. These results confirm that direct transition from MDI to Omnipod 5 is both effective and safe.
Q. How do these sustained improvements with the Omnipod 5 translate into potential benefits for people with type 1 diabetes in everyday clinical practice?
These findings are clinically significant because we now have the first tubeless AID system available for people with type 1 diabetes. Many patients, particularly those on MDI, have been waiting for this option, even though similar efficacy has been demonstrated with tubed systems.
From a practical perspective, the study also showed that transition to AID can be done safely and effectively on an outpatient basis. In my centre, and in others, this has already led to changes in practice, with more people now starting Omnipod 5 without hospital admission. This makes the therapy more accessible and less burdensome for patients.
Q. What are the next steps for evaluating the Omnipod 5 in type 1 diabetes, and how might these findings guide future treatment decisions or clinical practice?
The next step is to gather high-quality real-world evidence. Randomized controlled trials are the gold standard for proving efficacy and safety, but they are conducted in controlled environments with selected populations and intensive follow-up. We now need prospective real-world studies to confirm whether the benefits we saw in RADIANT are replicated in broader, more diverse patient populations with less frequent clinical contact.
There are also specific groups where further research is needed. For example, RADIANT included people with normal BMI and moderate insulin needs. However, many people with type 1 diabetes are overweight or obese and require higher insulin doses: the so-called “double diabetes” population. These patients also deserve access to tubeless AID systems, and we need to evaluate how well Omnipod 5 works for them.
Another important area is pregnancy. As more young people use Omnipod 5, we will increasingly face questions about whether it is safe and effective to continue during pregnancy. More data in this area will be crucial to guide clinical decisions.
About Dr Pieter Gillard
Dr Pieter Gillard is an endocrinologist at University Hospitals Leuven, Belgium, and Assistant Professor at KU Leuven. He specializes in type 1 diabetes management and the use of diabetes technology, including automated insulin delivery systems and continuous glucose monitoring. Dr Gillard has served as principal investigator in several international clinical trials, including the RADIANT study, and his research focuses on improving glycaemic outcomes and quality of life for people living with diabetes.
This content has been developed independently by Touch Medical Media for touchENDOCRINOLOGY. It is not affiliated with the European Association for the Study of Diabetes (EASD). Views expressed are the speaker’s own and do not necessarily reflect the views of Touch Medical Media.
