FLAIR: MiniMed 670G vs. advanced hybrid closed-loop (the future 780G algorithm) in adolescents and young adults
What this study tests
The first head-to-head crossover trial of two automated insulin delivery systems in adolescents and young adults (eligible ages 14 to under 30). The advanced hybrid closed-loop system (the algorithm that became the MiniMed 780G) cut daytime high blood sugar without raising lows, compared with the commercially available MiniMed 670G.
Editorial review: .
Registry checked: 2026-09-17. Registry’s own update: 2021-04-20.
Source dates appear in the references where available; this record has no dated citation metadata.
Trial status, labels and access can change between reviews. How we review the evidence · How to read the evidence
Evidence at a glance
- Who can enter the study?
- Adolescents and young adults aged 14 to 29 with type 1 diabetes for at least 1 year, already using an insulin pump or multiple daily injections, with HbA1c between 7.0% and 11.0% (53-97 mmol/mol). Recruited from seven academic endocrinology centers (four in the USA, one each in Germany, Israel, and Slovenia). Registered eligibility ↗Enrollment criteria describe who may enter. They do not establish who was analyzed or the denominator for a reported result.
- Reported benefit and results
- Yes. Among 113 participants (mean age 19, 62% female), the advanced system reduced daytime time-above-180 mg/dL from 37% (670G) to 34% (advanced), a difference of -3.0 percentage points (95% CI -3.97 to -2.04; p<0.0001). It did this without increasing dangerous lows: 24-hour time below 54 mg/dL was 0.50% on 670G versus 0.46% on the advanced system (difference -0.06%; p<0.0001 for non-inferiority). One severe low-glucose event occurred (in the advanced-system arm) and was judged unrelated to treatment; none occurred on 670G.Read the result sources and their limitations →
- Important harms
- Read the reported results, safety discussion and original sources. A separate harms summary is not available; this does not establish safety.
- Research access and approval
- Study regions: United States, European Union, Other regions. A trial listing does not establish product approval or current recruitment at a particular site. Check the study’s current entry requirements.
- What remains uncertain?
- Read the full discussion and original sources for study limitations. Planned endpoints and completion dates are not results.
Research status alone does not establish approval, clinical benefit or local availability.
Primary endpoints
- Proportion of time glucose was above 180 mg/dL (>10.0 mmol/L) during the daytime (06:00-23:59), tested for superiority
- Proportion of time glucose was below 54 mg/dL (<3.0 mmol/L) over the full 24-hour period, tested for non-inferiority (margin 2%)
The full picture
What was tested and why it matters
Closed-loop insulin systems (sometimes called an "artificial pancreas") link a continuous glucose monitor to an insulin pump and let an algorithm adjust insulin automatically. FLAIR ran a head-to-head, randomized comparison of two such systems to see whether a newer algorithm could do better than one already on the market.1 It compared the commercially available Medtronic MiniMed 670G against an investigational "advanced" hybrid closed-loop system — the algorithm that was later sold as the MiniMed 780G — which adds automatic correction doses on top of background insulin.1
Adolescents and young adults often face additional challenges in meeting glucose targets. FLAIR focused on this age group without treating those challenges as a personal failing.1
Who it was for
Eligibility was age 14 to under 30; the trial enrolled people aged 14 to 29 who had lived with type 1 diabetes for at least a year and had an HbA1c between 7.0% and 11.0%.2 They were recruited from seven academic centers: four in the United States and one each in Germany, Israel, and Slovenia.1
How it was designed
FLAIR was a multicenter, randomized, crossover trial.1 After a run-in period to learn the equipment, each participant used one system for 12 weeks, then crossed over (with no washout) to the other system for another 12 weeks, so everyone tried both.1 Because the two systems look and behave differently, neither participants nor staff could be blinded.1 There were two co-primary outcomes, both measured by continuous glucose monitor: daytime time spent above 180 mg/dL (tested to see if the advanced system was better), and 24-hour time spent below 54 mg/dL (tested to confirm it was no worse).1 As a device study, it carried no drug-trial phase number.2
Key results
Among the 113 participants (mean age 19; 62% female), the advanced system reduced daytime time-above-180 mg/dL from 37% to 34% — a difference of 3 percentage points (95% CI -3.97 to -2.04; p<0.0001).1 Crucially, it achieved this without causing more lows: time below 54 mg/dL was 0.50% on the 670G versus 0.46% on the advanced system (p<0.0001 for non-inferiority).1 Only one severe low-glucose event occurred during the whole trial, in the advanced-system arm, and reviewers judged it unrelated to the device.1
What it means and what's next
FLAIR showed that smarter algorithms — chiefly automatic correction doses — can squeeze out more high glucose in adolescents and young adults without increasing time below 54 mg/dL.1 The investigational system went on to become the marketed MiniMed 780G. The authors noted that the next priorities are testing these systems in underserved populations, during pregnancy, and in people with impaired awareness of low glucose.1
Sources
- [1]
- [2]ClinicalTrials.gov. FLAIR, NCT03040414 · Trial registry