PARAISO BN44715 (PARAISO)

Evaluating the Safety and Effects of an Investigational Medication for Early-Stage Parkinson's Disease

Recruiting
50 years - 85 years
All
Phase 3
900 participants needed
1 Location

Brief description of study

The purpose of this study is to evaluate the efficacy, safety, and pharmacokinetics (PK) of prasinezumab compared with placebo in participants with early-stage Parkinson's disease (PD) on stable symptomatic monotherapy with levodopa.

Eligibility of study

You may be eligible for this study if you meet the following criteria:

  • Conditions: Parkinson's Disease
  • Age: 50 years - 85 years
  • Gender: All

Inclusion Criteria:

  • Body weight within 40-110 kilograms (kg) (88-242 pounds [lbs]) and a body mass index within the range 18-34 kg/m2
  • Diagnosis of idiopathic PD based on Movement Disorder Society (MDS) criteria
  • Has received monotherapy treatment
  • An MDS-UPDRS Part IV score of 0 at screening and prior to randomization
  • Hoehn and Yahr (H&Y) Stage 1 or 2 off medication at screening and prior to randomization
  • Agreement to adhere to the contraception requirements

Exclusion Criteria:

  • Pregnant or breastfeeding, or intention of becoming pregnant during the study or within the time frame in which contraception is required
  • Medical history indicating a parkinsonian syndrome other than idiopathic PD
  • Diagnosis of a significant neurologic disease other than PD
  • Chronic uncontrolled hypertension

This study investigates the effects of an investigational medication compared to a placebo in individuals with Parkinson's disease.

The study evaluates the safety, effectiveness, and how the body processes the investigational medication. It looks at participants who are already on a stable treatment.

  • Who can participate: Adults with early-stage Parkinson's disease on stable monotherapy with levodopa, weighing between 40-110 kg, can participate.
  • Study details: Participants will receive either the investigational medication or a placebo. A placebo is an inactive substance that looks like the investigational medicine but does not contain any medicine.
Updated on 06 Jul 2026. Study ID: 25-1603

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