Rockley completes human studies of blood pressure monitor
Laser-based wearable shows promise that it will perform as well as traditional cuff-based medical devices
Rockley Photonics has announced initial results from two human studies using a first-generation Alpha prototype of its non-invasive and laser-based cuffless blood pressure monitor. This wearable device is currently in advanced development.
The first study successfully demonstrated intra-subject tracking of blood pressure compared to measurements using an intra-arterial pressure transducer, or an A-line, which is the gold-standard method to continuously monitor blood pressure during surgery and in the ICU. Thirty subjects participated in the study, where blood pressure changes were induced using a repeated leg press exercise.
Using only the Rockley laser-based signal and a single-point blood pressure calibration, blood pressure changes from -10 mmHg to +25 mmHg were within target accuracy according to both FDA recognized consensus standards ISO 81060-2 and IEEE 1708. Future studies will focus on expanded blood pressure ranges.
A second longitudinal study followed subjects with repeat visits up to 34 days post calibration. Here, Rockley device predictions were compared to dual-observer auscultation measurements (cuff-based with split stethoscope). Subjects included both healthy and hypertensive adult volunteers between ages 18 and 71 years.
Despite real-world variability in device placement, the use of multiple devices per subject, and higher reference error, the longitudinal study results were comparable to the A-line study over the same BP range, and within sight of meeting the ISO 81060-2 and IEEE 1708 accuracy targets. Notably, the error did not increase over the time period from initial calibration.
Rockley says that the results from the Alpha-wearable strongly justify the continued development of the Rockley cuffless blood pressure device. Richard Kuntz, MD, scientific advisor to Rockley said: “Reliable acquisition of blood pressure is necessary to aid in the early diagnosis and continued monitoring of patients that require management of a variety of cardiovascular conditions. Rockley’s device shows promise that it will perform with the accuracy expected from traditional medical devices, which can vastly improve patient compliance and overall case management.”
Potential use cases for the device focus on management of hypertension in various patient populations, where frequent insight may be leveraged in challenging-to-monitor scenarios, such as those that experience white coat hypertension or undergo regular treatments for kidney disease or heart failure.
Zahi Fayad, director of the BioMedical Engineering and Imaging Institute at the Icahn School of Medicine at Mount Sinai said: “There’s an art to taking a reliable blood pressure measurement using a traditional cuff. However, blood pressure measurements using wearables have long been a challenge. “It is very exciting to see this cuffless technology becoming available, as it enables frequent measurements and can provide a seamless and easy practitioner and patient experience,” Fayad continued. “Rockley’s current findings show accurate blood pressure values compared to a gold standard over a certain range. I am excited to see the continuation of the program to generalize the findings.”
Rockley plans to engage with the FDA in the coming months to obtain feedback on future clinical study design and data analysis.
