Study Rationale: In preclinical models, detection of apoptosing retinal cells (DARC) allows identification of cells in the eye that are under stress and at risk of damage from Parkinson’s disease (PD) before the cells become compromised. By quantifying these “at-risk” cells, DARC has the potential to identify individuals who are at a greater risk of disease progression – a clinical measure for which no current tests exist. DARC can also be used to rapidly assess the effectiveness of treatments that reduce cell stress and the likelihood of future cell damage, thus accelerating the development of disease-modifying treatments for PD.
Hypothesis: We hypothesize that measuring the quantity and patterns of retinal cell stress using DARC technology will allow identification of PD progression earlier than current methods and facilitate the evaluation of drug effectiveness.
Study Design: At the start of the study, we will clinically assess and perform DARC imaging on 40 people with PD. We will continue with DARC and clinical assessments at 6, 12 and 24 months after the initial evaluation to assess whether a large DARC signal at presentation (or subsequently) translates into worsening of clinical scores, and we will calculate the time to clinical deterioration following increase of DARC signal. We will also perform a single DARC assessment on 20 healthy volunteers to validate differences between people with and without PD.
Impact on Diagnosis/Treatment of Parkinson’s disease: Identifying individuals in which PD is likely to worsen within months will facilitate monitoring, screening and initiation of appropriate treatment. Further, DARC can reveal within hours whether a potential treatment can reduce cellular stress, compared to current methods for establishing drug effectiveness, which can take years.
Next Steps for Development: If successful, future studies using a larger cohort of people with PD will further validate the findings and develop DARC as a community-based diagnostic tool for PD.