During the height of the COVID-19 pandemic, numerous clinical trials were paused or transitioned, if possible, to virtual or hybrid clinical trials. These types of trials leveraged a variety of modalities, including telemedicine, remote visits, and various sensors or wearable technology.
Not all disease indications or types of trials are suitable for virtual or hybrid clinical trials, although often components of hybrid trials might be suitable for most studies. Wearables, for example, such as smartwatches and exercise monitors, can provide a wealth of real-time physiological data that can be applied to a broad range of investigations, ranging from preclinical studies to determine patient suitability, through Phase I, II and III clinical trials, and in post-approval studies for enhanced monitoring for late toxicity or disease recurrence.
Before treatment. Data from wearables can be used to assist in determining which treatment may be the best fit of treatment for patients — and conversely, it may also help to better select the right patients for treatment. The current "gold standards" for assessing patient fitness prior to initiative of an anti-cancer therapy include performance status measurements such as the Eastern Cooperative Oncology Group (ECOG) scale or the Karnofsky scale (both of which have well-documented limitations).
The Karnofsky Performance Scale Index, for example, allows physicians to classify patients by their functional impairment. to compare the effectiveness of different therapies and to evaluate the prognosis of individual patients. The ECOG scale is similar, describing a patient's level of function in terms of their ability to care for themselves, daily activity, and physical ability, such as walking or working.
Although widely used in oncology, there is a significant level of subjectivity and selection bias inherent to both of these scales that has been linked to disparities in clinical trial outcomes.¹ They depend upon patients reliably describing their activity level, or upon subjective observations by a healthcare provider during a brief patient visit.
However, a wearable actigraphy device, such as an Apple Watch, Fitbit, Garmin or other, can provide very accurate step counts, as well as vast amounts of objective physiological data, such as temperature, blood pressure, oxygen saturation, respiratory rate, heart rate, and sleep patterns. Unlike collecting data at a single clinic visit, which creates discrete data points, wearables and similar monitors collect a range of data over an extended period of time that can provide useful clinical and physiological insights.
During Treatment. During cancer treatment, wearables can be used to improve the evaluation of patients to enhance supportive care for patients with low activity levels. For example, they can be used to track daily step counts as a dynamic predictor of patient hospitalizations during chemoradiotherapy.² In a study that evaluated wearable activity tracking in patients receiving radiation therapy for solid tumors of the head, neck, lung or gastrointestinal tract, a 36% reduction in the risk of hospitalization for every 1,000 daily steps was observed. The authors of the study concluded that continuous activity monitoring during chemoradiotherapy was feasible and should be used to optimize supportive care during cancer therapy.
Post Treatment. Wearables can be used to enhance monitoring for late toxicity or disease recurrence and to promote healthy lifestyles in the survivorship period. For example, there is an ongoing study sponsored by the Alliance for Clinical Trials in Oncology, known as the Breast Cancer Weight Loss Study (BWEL)³ ⁴ that is evaluating whether weight loss in overweight and obese women may prevent breast cancer from recurring. The goal is to test whether patients who take part in a weight loss program after being diagnosed with cancer have a lower rate of cancer recurrence compared to women who do not take. Patients used a variety of technology, including wearables and telemedicine applications, to monitor daily activity level, weight and food intake, which was shared with their "health coaches" to help them hit their weight-loss goals.
Advantages and disadvantages of "continuous monitoring"
Any method for capturing data has both pros and cons; wearables are no different.
Advantages
Continuous monitoring has the potential to be more reliable than spot checks and conventional assessments like performance status and patient-reported quality-of-life data. They can also provide more detailed and complete characterization and detection of physiological events. Wearables can be suitable for a broad range of uses in clinical research and care, including preliminary patient physical assessments, assistance with symptom triage (COVID-19, for example), and monitoring patients after hospital discharge. They also support efficacy and safety observations in clinical trials, whether remote or decentralized. Also, because traditional spot-checks and site visits do not provide a range of continuous data, continuous monitoring has the potential to fill in gaps in clinical trial data.
A recurring theme in clinical trial planning is patient-centricity. Wearables can minimize trips to clinic sites and may provide study participants and cancer patients with a feeling of having more control over how they manage their own illness.
Disadvantages
It is important that study designers understand the limitations and advantages of various wearable form factors, such as physical size and shape, battery life, complexity of use, as well as corresponding data collection protocols. They must choose wearable devices using a fit-for-purpose approach and know how to interpret the values those devices generate. It is also necessary to determine the reliability and accuracy of the data collected, and any potential interfering factors.
Remember, patients are unlikely to use uncomfortable wearables or use them properly if they are complicated, require much training and are not "patient-friendly." Nonetheless, with the accessibility and cost-effectiveness of modern wearables, as well as the broad range of data they can collect, wearable devices are becoming an increasingly important component of oncology treatment strategies, preclinical, clinical and post-approval studies.
References
¹ Kelly CM and Shahrokni A. Moving beyond Karnofsky and ECOG Performance Status Assessments with New Technologies. J Oncol. 2016. https://www.hindawi.com/journals/jo/2016/6186543/
² Izmailova E, Huang C, Cantor M, Ellis R, Ohri N. Daily step counts to predict hospitalizations during concurrent chemoradiotherapy for solid tumors. J Clin Oncol. 2019;37, no. 27_suppl:293-293. https://ascopubs.org/doi/abs/10.1200/JCO.2019.37.27_suppl.293
³ Breast Cancer Weight Loss Study (BWEL Study). https://clinicaltrials.gov/ct2/show/NCT02750826
⁴ Moninger J. Can Fitness Trackers Improve Health in Cancer Survivors? Cure. Summer 2017;1(1). https://www.curetoday.com/view/can-fitness-trackers-improve-health-in-cancer-survivors