A groundbreaking smartphone application could revolutionize clinical trials for Huntington's disease by providing a more sensitive and convenient method to track disease progression, according to new research published in Brain by scientists at University College London (UCL) and Roche.
The study introduces the Huntington's Disease Digital Motor Score (HDDMS), a digital biomarker that demonstrates approximately twice the sensitivity of the currently most used clinical measure, the composite Unified Huntington's Disease Rating Scale, in detecting real changes in motor function.
Digital Assessment Transforms Disease Monitoring
The HDDMS system requires participants to complete five simple tests of movement control through a custom smartphone app, including assessments of balance, finger tapping, and involuntary movements. The entire evaluation takes just five minutes and can be performed in patients' homes, offering significant advantages over traditional clinic-based assessments.
"Our findings suggest that incorporating the HDDMS in clinical trials will help to give clearer answers about whether a potential treatment is working, with fewer participants or shorter lead times than conventional measures," said Professor Ed Wild from UCL Huntington's Disease Centre.
The scoring system operates on a straightforward principle: lower HDDMS values indicate better motor function, while higher values reflect worse motor function. By regularly performing these tests in their everyday lives, patients' disease progression can be continuously monitored by doctors and researchers.
Clinical Trial Efficiency Breakthrough
The enhanced sensitivity of the HDDMS could significantly impact clinical trial design and execution. Researchers anticipate that the digital tool will enable detection of even small changes in symptoms, making it easier to evaluate the potential of new treatments while requiring fewer participants and shorter study durations.
"More sensitive tools to measure disease progression are particularly valuable in rare diseases like Huntington's disease. The fewer people there are who can possibly participate in clinical trials, the more important it becomes to minimise trial burden and size," Professor Wild explained.
This efficiency gain comes at a critical time, as promising new therapies for Huntington's disease are currently undergoing clinical trials, making the accuracy and efficiency of the HDDMS particularly valuable.
Comprehensive Development and Validation
The HDDMS was developed using data collected from 1,048 people across four observational and interventional studies. From a large battery of novel digital tasks presented via the smartphone app, researchers identified and distilled the measurements that best predicted disease progression.
The research team emphasizes that the convenience factor extends beyond mere practicality. "The fact that the HDDMS is evaluated in a five-minute assessment in people's homes makes it convenient and potentially more meaningful than in-clinic measures of motor impairment," Wild noted.
Addressing Critical Medical Need
Huntington's disease represents a devastating, inherited neurodegenerative condition that causes progressive loss of movement control, thinking, and behavior. Currently, no cure exists, and existing treatments primarily focus on managing symptoms rather than slowing or stopping the disease progression itself.
The new research underscores the growing role of digital biomarkers in neurological research and highlights the potential for technology-driven innovations in disease monitoring and drug development. The HDDMS is now available to academic and industry parties working on Huntington's disease through Roche Diagnostics.
Study Limitations and Future Directions
The researchers acknowledge several limitations in their work. All data has been collected from people participating in specific clinical trials, meaning the HDDMS has not been evaluated in people before symptom onset or in those with advanced Huntington's disease.
Additionally, while the HDDMS demonstrates sensitivity to changes, more research is needed to confirm its ability to predict long-term functional decline. These limitations suggest areas for future investigation as the digital biomarker approach continues to evolve.
