In January 2021 Novartis acquired Cadent Therapeutics. As part of a pipeline reassessment, the Synchrony-1 trial will not proceed as initially scheduled.

This is a randomized, double-blind, placebo-controlled Phase 2 study evaluating oral administration of CAD-1883 in the treatment of adults with a genotypic diagnosis of Spinocerebellar Ataxia (SCA). This study offers the opportunity to understand the safety, tolerability, and efficacy of CAD-1883 in the SCA patient population.

This is a randomized, double-blind, placebo-controlled Phase 2 study evaluating oral administration of CAD-1883 in the treatment of adults with a genotypic diagnosis of SCA using multiple dose levels. The study will include multiple cohorts of 16 patients each where 12 patients will be randomized to CAD-1883 and 4 to matching placebo.

Potential subjects will undergo a screening period (14 to 28 days), a baseline (Day 1) visit, and a 12-week treatment period. A follow-up visit will occur 4 weeks after the end of the treatment period. The total duration of individual subject participation may be up to 20 weeks, depending on the duration of the screening period.

The study will assess safety by adverse events, vital signs, laboratory parameters (including chemistry, hematology and urinalysis); pharmacokinetics of CAD-1883; and efficacy measures by Scale for the Assessment and Rating of Ataxia (SARA), clinician/patient rating of ataxia and symptoms, patient quality of life measures and wearable sensors to capture falls and gait measurements.

For planning purposes, the anticipated study completion date assumes evaluation of 3 cohorts.

Key Inclusion Criteria:

• Prior Spinocerebellar Ataxia (SCA) diagnosis of the following SCA genotypes: SCA1, 2, 3, 6, 7, 8, 10, 17, or Autosomal Recessive Cerebellar Ataxia Type 1 (ARCA1).
• Scale for the Assessment and Rating of Ataxia (SARA) Total score ≥8 and <30 at Screening
• SARA item #1 (gait) score of ≥2 at Screening
• Ability to ambulate 8 meters at Screening without assistance from another person

Key Exclusion Criteria:

• Neurological condition other than SCA that could predominantly explain or contribute significantly to the subjects' symptoms of ataxia or that could confound the assessment of ataxia symptoms (e.g., chronic alcoholism, vitamin deficiencies, multiple sclerosis, Parkinson's disease, Friedreich's ataxia, vascular disease, tumors, paraneoplastic disease, head injury, idiopathic late onset ataxia, multisystem atrophy, stroke, arthritis, cerebral palsy, spasticity of unknown origin).
• Moderate or severe scores on the following Inventory of Non-Ataxia Signs (INAS) items at Screening: Dystonia: at least 3 of 5 items; Spasticity: at least 2 of 3 items; Rigidity: at least 2 of 3 items