There is an urgent need for the development of digital progression biomarkers, which are sensitive to detect small, but potentially clinically relevant changes in the disease course. Digital biomarkers are based on (i) continuously collected real-time data, during the patient's day to day activities; and (ii) task-based assessment. In this study the investigators are interested in developing algorithms for the detection of disease progression in PSP patients in key clinical parameters: bradykinesia, gait, rising from a chair and falls, based on (i) sensor data obtained by means of passive monitoring during daily living; and (ii) sensor data collected during the Virtual Motor Exam.

Rationale In light of the advent of a wide range of new disease modifying treatments, and acknowledging that existing clinical outcome measures may well be insufficiently sensitive to detecting small but potentially clinically relevant changes in the disease course, there is an urgent need for development of digital progression biomarkers, not only in the field of Parkinson's disease, but also in the field of the various forms of atypical parkinsonism, including Progressive Supranuclear Palsy (PSP).

Study Design Prospective, longitudinal, single-center cohort study.

Study Objectives The primary objective is to develop algorithms for the detection of disease progression in PSP patients in key clinical parameters: bradykinesia, gait, rising from a chair and falls, based on (1) sensor data obtained by means of passive monitoring during daily living; and (2) sensor data collected during the Virtual Motor Exam.

The second objective of this study is to create a longitudinal dataset describing the clinical and functional characteristics of a representative PSP cohort to allow researchers to investigate important unanswered questions in PSP.

Study population 50 patients with possible or probable PSP, according to established international criteria (i.e., MDS-PSP criteria); diagnosis confirmed by consensus review of a videotaped neurological examination by two neurologists with deep expertise in movement disorders. In addition, we will include 50 age and gender matched healthy controls.

Main study parameters/endpoints The primary study endpoints are the annual changes in the newly developed digital measurements, extracted from the Verily Study Watch. Secondary endpoints include standardized evaluations for motor, cognition, neuropsychological, quality of life and ADL assessments. Additionally, whole blood for DNA and serum will be collected in the PSP subjects, to use for e.g. genotyping and phenotyping.

Nature and extent of the burden and risks associated with participation, benefit and group relatedness For data collection, the study assessor will visit each participant at home twice within an interval of 1 year ± 60 days. All study assessments are routine exams done in standard clinical practice and are generally well tolerated, which takes up to 2 hours each time. PSP subjects will also be asked to consent to a blood draw once. During their 1-year participation, each participant will wear the Verily Study Watch daily for up to 23 hours. This small, unobtrusive electronic device is easily worn and poses no significant safety risk. All participants will be asked to complete a set scheduled tasks twice a day, once a week, which altogether takes 15-20 minutes of their time.

As data collection is not performed for immediate diagnostic or therapeutic purposes, there will be no direct benefits for the subjects enrolled in this study. Patients may indirectly benefit from the study, as their data contribute to providing novel etiological insights for improving the use of existing treatments, developing of new therapeutic approaches, and increasing the precision of personalized disease management.

Inclusion Criteria (PSP cohort):

• Subject has possible or probable PSP, according to the established international criteria defined by the Movement Disorders Society (MDS-PSP criteria, Höglinger et al, 2017); diagnosis is confirmed based on by consensus review process. In addition to the diagnosis of the own treating neurologist, the diagnosis always needs to be confirmed by at least one neurologist with deep expertise in movement disorders. The videotaped neurological examination as obtained during visit 1 will be used by the expert neurologist.
• Subject is an adult, at least 50 years of age.
• Subject can read and understand Dutch.
• Subject has completed the Informed Consent, as approved by the Institutional Review Board (IRB).
• Subject is willing, competent, and able to comply with all aspects of the protocol.
• Subject is able to walk at least 5 steps with or without minimal assistance (ie, stabilization of 1 arm or use of a cane or walker).

Inclusion Criteria (HC cohort):

• Subject has no neurological or musculoskeletal disorder or any other condition that impairs movement, gait, or balance, in the opinion of the Investigator.
• Subject is an adult, at least 50 years of age.
• Subject can read and understand Dutch.
• Subject has completed the Informed Consent, as approved by the IRB.
• Subject is willing, competent, and able to comply with all aspects of the protocol.
• Subject is able to walk at least 5 steps with or without minimal assistance (i.e., stabilization of 1 arm or use of a cane or walker).

Exclusion Criteria (PSP and HC cohorts):

• Subject has an additional condition or situation that, in the opinion of the Investigator, makes the subject inappropriate for participation in the study.
• For Study Watch: subject is allergic to nickel.

PSP-cohort: any adult with PSP who meets the inclusion criteria and does not meet the exclusion criteria.

HC-cohort: any adult who meets the inclusion criteria and does not meet the exclusion criteria.

The dataset generated in this study will become available to qualified researchers worldwide, provided research questions are approved by the Research and Data Sharing Review Committee (RDSRC). The RDSRC will protect subjects' privacy by limiting the availability of the study data and controlling access to sources of information that might potentially be used to identify the individual subjects associated with the bio-specimen analysis. The RDSRC will assess the relevance and scientific quality of research proposals for which study data or material is requested. These responsibilities include the consideration of applications for:

• access to the resources obtained in this study, including data or biomaterials
• applications for endorsement of a scientific project using study materials;
• applications for endorsement of a clinical study using study materials.

Not decided yet.

No list of criteria is available yet.