Abstract Details

To gather regulatory qualification as a primary endpoint of the 95th centile of stride velocity, a digital outcome obtained by a wearable device. The context of use is ambulant patients with Duchenne Muscular Dystrophy

We have developed a wearable device to measure patients’ movements continuously and accurately in the uncontrolled environments of everyday life and a platform of clinical outcomes to summarize data into clinically meaningful indicators.One of these outcomes, the 95th centile stride velocity (SV95C), represents the 5% most rapid strides performed by a patient over a span of at least 50 hours.

SV95C properties were studied in 125 ambulant patients with Duchenne, aged 5 to 14 years, from 6 different natural history studies and clinical trials and from patients attending routine clinic appointments.

The median error of stride velocity in comparison with gold standard motion capture was measured with 0.01 cm/s precision. The reliability of the SV95C measured during a  > 50h period was 0.97. Compliance rate in uncontrolled environment was over 85%. The clear and rapid sensitivity to positive change in patients given steroids, as well as sensitivity to negative changes in patients from natural history significantly outperformed hospital-based assessments such as 6 minutes-walking-test.

On January 23^rd 2023, the SV95C (Stride Velocity 95^th centile) received positive opinion by the European Medical Agency to become a qualified primary endpoint for ambulant patients living with Duchenne Muscular Dystrophy, opening the way to public consultation. A similar application is ongoing at the FDA.