Measuring Mobility in the Real World: The Mobilise-D Study

[Authors: Laura Delgado (Predoctoral Researcher at ISGlobal) and Magda Bosch de Basea (Postdoctoral Researcher at ISGlobal)]

Recently, the European Medicines Agency (EMA) published a letter of support for the general objective of the Mobilise-D consortium to pursue the qualification of digital mobility outcomes (DMOs) as biomarkers of mobility. This marks an important milestone in the long road ahead for Mobilise-D; for the ISGlobal team involved in the study, it is a tremendous dose of encouragement from one of the world’s largest regulatory agencies to continue pushing forward, especially in these turbulent times. Let us briefly explain what this all means.

First of All, Why Assess Mobility?

The ability to move from one place to another is a key contributor to physical, mental and social well-being. In our daily lives, this ability allows us to exercise, take walks with friends or go grocery shopping. At home, it allows us to engage in self-care activities and move from our bedroom to the toilet, kitchen or living room. In both cases, mobility is essential to living a functional and autonomous life.

The European Medicines Agency (EMA) letter of support for the general objective of the Mobilise-D consortium it is a tremendous dose of encouragement from one of the world’s largest regulatory agencies to continue pushing forward, especially in these turbulent times

However, this ability diminishes over time and in the presence of chronic conditions. The increasing longevity of the world’s population, together with prolonged survival in many chronic diseases, means that more people are suffering from a loss of mobility and, consequently, a loss of independence.

The current mobility assessment instruments are unable to detect important changes in mobility patterns beyond walking speed. Therefore, if we improve our ability to assess mobility in real-world scenarios and account for other critical mobility parameters such as balance, step symmetry and cadence, we will be able to detect changes sooner and adapt clinical practice to a more personalised care.

Likewise, from a public health point of view, we will be able to revolutionise the prevention of mobility loss by testing and promoting interventions that could effectively impact mobility impairment progression and provide the pharmaceutical industry with a powerful tool for developing drugs targeted at improving mobility outcomes.

The current mobility assessment instruments are unable to detect important changes in mobility patterns beyond walking speed

What Is Mobilise-D About and How Are We Involved?

Mobilise-D is a large European consortium funded through the Innovative Medicines Initiative (IMI) that aims to provide a new way of measuring mobility in real-world scenarios using digital sensors and validating the ability of this method to predict clinical outcomes in patients with various mobility impairments, namely Parkinson’s disease, multiple sclerosis, chronic obstructive pulmonary disease (COPD) and proximal femoral fracture. The system, consisting of an algorithm-sensor pair, will collect DMOs that can later on be used as biomarkers of mobility in research and clinical practice. However, in order for this system and DMOs to accurately assess daily-life mobility, they need to be validated from a technical, clinical and regulatory perspective.

The Mobilise-D consortium is composed of 34 partners, including ISGlobal, as well as many other universities, research centres, hospitals, healthcare technology enterprises and large pharmaceutical companies in Europe, the Middle East and the United States. This multidisciplinary group represents some of the world’s leading experts in mobility assessment and in the use of wearable sensors.

Mònica Moreno / Barcelona City Council

At ISGlobal, we are a team of researchers from diverse backgrounds leading the epidemiological and statistical analyses. In the coming years, we will be particularly involved in the analysis of data from a large cohort study that will follow 2,400 patients with Parkinson’s disease, multiple sclerosis, COPD and proximal femoral fracture for two years. Moreover, we will also contribute to this study with the assessment and follow-up of COPD patients recruited in Barcelona.

In the coming years, we will be particularly involved in the analysis of data from a large cohort study that will follow 2,400 patients with Parkinson’s disease, multiple sclerosis, COPD and proximal femoral fracture for two years

What Are the Technical, Clinical and Regulatory Validations?

Briefly, technical validation will demonstrate the validity of our algorithm-sensor pair by comparing the data captured to data collected through gold-standard methods. Clinical validation will demonstrate the ability of the measured DMOs to predict specific clinical endpoints in a large observational cohort study including over 2,400 patients diagnosed with the four chronic conditions mentioned above.

Regulatory validation will bring DMOs to health authorities and regulators (EMA, FDA, HTA) so that they can be accepted for use in research, drug development and clinical practice. Bringing to the conversation a topic that is so complex requires a specific strategy and lots of work. This is why the dialogue with the EMA has followed an incremental approach in which DMOs are presented first as biomarkers of mobility for a single disease, and later for all the others.

The dialogue with the EMA has followed an incremental approach in which DMOs are presented first as biomarkers of mobility for a single disease, and later for all the others

What Is the Letter of Support From EMA About?

In October 2019, we submitted a formal request for qualification advice from the EMA by presenting the case for DMOs as monitoring biomarkers in Parkinson's disease. Meetings with regulators took place in March 2020 and the support of the agency was obtained shortly thereafter. The official result of this qualification advice was published as a letter of support stating that "the EMA supports the general objective of the Mobilise-D consortium to pursue the qualification of DMOs as biomarkers of mobility performance in regulatory drug trials".

This is excellent news and a clear demonstration that hard work pays off. It represents a significant milestone in the project, but it is only the beginning of a longer road towards regulatory success

This is excellent news and a clear demonstration that hard work pays off. It represents a significant milestone in the project, but it is only the beginning of a longer road towards regulatory success. We are currently presenting the case for the use of DMOs as biomarkers of mobility in other chronic conditions (multiple sclerosis, COPD and proximal femoral fracture) and we hope to receive the support of the EMA again.

For more information on the project and its accomplishments, please visit the website www.mobilise-d.eu or follow us on Twitter, Facebook and LinkedIn.