> Trialight public data. Index of pages: https://trialight.com/llms.txt > Web page: https://trialight.com/data/trial/a-study-to-evaluate-the-efficacy-and-safety-of-intravenous-1269a3d8-2519-4b21-a6fc-86cf80a4f5c4 > Record changed: 2026-11-04 # A Study to Evaluate the Efficacy and Safety of Intravenous (IV) Prasinezumab in Participants With Early-Stage Parkinson's Disease NCT07174310 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) Phase Phase 3 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) Recruitment status Recruiting Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) Participants 900 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) Lead sponsor Hoffmann-La Roche Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) Start date 2025-11-24 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) Number of sites 192 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) ## Title and summary **Summary** 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. Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) **Acronym** PARAISO Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) **Short title** A Study to Evaluate the Efficacy and Safety of Intravenous (IV) Prasinezumab in Participants With Early-Stage Parkinson's Disease Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) **Official title** A Phase III, Randomized, Double-Blind, Placebo-Controlled, Multicenter Study to Evaluate the Efficacy and Safety of Intravenous Prasinezumab in Participants With Early-Stage Parkinson's Disease Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) ## Status and phase **Registry reports results** No Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) **Listing at source** Listed Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) **Recruitment status** Recruiting Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) **Phase** Phase 3 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) **Study type** Interventional Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) ## Dates **Completion date** 2031-06-30 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) **First posted** 2025-09-15 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) **Registry last updated** 2026-10-06 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) **Primary completion date** 2029-06-30 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) **Start date** 2025-11-24 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) ## Size and sites **Participants** 900 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) **Participant count basis** Estimated Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) **Planned participants** 900 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) **Protocol amendments** 0 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) **Number of sites** 192 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) ## Sponsor and oversight **Data monitoring committee** Yes Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) **Registry sponsor category** Industry Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) **Lead sponsor** Hoffmann-La Roche Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) **Source registry** ClinicalTrials.gov Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) ## Identifiers **Registry ID** NCT07174310 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) **ClinicalTrials.gov ID** NCT07174310 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) **Registry record** Open registry record Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) ## Study design **Allocation** Randomised **Model** Parallel groups **Purpose** Treatment **Masking** Triple masking **Masked roles** Participants, Investigators, Outcome assessors Sources for study design Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) ## Outcomes ### Primary outcomes 1. Time to Confirmed Motor Progression Event on Movement Disorder Society - Unified Parkinson's Disease Rating Scale (MDS-UPDRS) Part III Score Timeframe: Up to at least Week 104 ### Secondary outcomes 1. Change From Baseline in Motor Function as Measured by the MDS-UPDRS Part III off Medication Score Timeframe: Baseline, Week 104 2. Time to Worsening of Participants Motor Function as Reported by the Participant in the Presence of a Confirmed Motor Progression Event Timeframe: Up to at least Week 104 3. Time to Meaningful Worsening in Clinician Global Impression of Change (CGI-C), Overall Disease Subscale Timeframe: Up to at least Week 104 4. Time to increase in Levodopa Equivalent Daily Dose (LEDD) Timeframe: Up to at least Week 104 5. Percentage of Participants With Treatment Emergent Adverse Events (TEAEs) Timeframe: From Baseline up to 70 days after the final study dose (up to at least Week 104) 6. Percentage of Participants With Adverse Events of Special Interest (AESI) Timeframe: From Baseline up to 70 days after the final study dose (up to at least Week 104) 7. Percentage of Participants With Infusion Related Reactions (IRRs) Timeframe: From Baseline up to 70 days after the final study dose (up to at least Week 104) 8. Percentage of Participants With Suicidal Ideation, as Measured by the Columbia-Suicide Severity Rating Scale (C-SSRS) Timeframe: From Baseline up to 70 days after the final study dose (up to at least Week 104) 9. Serum Concentration of Prasinezumab Timeframe: Predose and postdose at Baseline, Week 1, 4, 12, 24, 36, 52, 76, and after week 76 every 12 weeks thereafter until end of study (up to at least Week 104) 10. Percentage of Participants With Anti-drug Antibodies (ADAs) Against Prasinezumab at Baseline Timeframe: At Baseline 11. Percentage of Participants With ADAs Against Prasinezumab During the Study Timeframe: From Baseline up to 70 days after the final study dose (up to at least Week 104) Sources for outcomes Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) ## Eligibility **Sex** All **Age groups** Adults, Older adults **Minimum age** 50 Years **Maximum age** 85 Years **Healthy volunteers** No ### 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 Sources for eligibility Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) ## Sites - University of Alabama at BirminghamBirmingham, United StatesRecruiting - Barrow Neurological InstitutePhoenix, United StatesRecruiting - Neurology Center of North Orange CountyFullerton, United StatesRecruiting - UC San DiegoLa Jolla, United StatesRecruiting - Keck School of Medicine of USCLos Angeles, United StatesRecruiting - UCLA Neurology Outpatient ClinicLos Angeles, United StatesRecruiting - Parkinson?s Research Centers of America ? Palo AltoPalo Alto, United StatesRecruiting - Profound Research LLC at The Neurology Center of Southern CaliforniaPasadena, United StatesRecruiting - UCSF Weill Institute for NeurosciencesSan Francisco, United StatesRecruiting - Stanford Neuroscience Health Center (SNHC)Stanford, United StatesRecruiting - Rocky Mountain Movement DisordersEnglewood, United StatesRecruiting - Institute for Neurodegenerative DisordersNew Haven, United StatesRecruiting - Georgetown UniversityWashington D.C., United StatesRecruiting - JEM Research LLCAtlantis, United StatesRecruiting - Parkinson's Disease and Movement Disorders Center of Boca RatonBoca Raton, United StatesRecruiting - K2 - VillagesLady Lake, United StatesRecruiting - K2 Medical Research-MaitlandMaitland, United StatesRecruiting - Baptist Hospital of MiamiMiami, United StatesRecruiting - Charter Research - Winter Park/OrlandoOrlando, United StatesRecruiting - Advent Health OrlandoOrlando, United StatesRecruiting - USF Parkinsons Disease and Movement Disorders CenterTampa, United StatesRecruiting - Grady Memorial HospitalAtlanta, United StatesRecruiting - Hawaii Pacific NeuroscienceHonolulu, United StatesRecruiting - Northwestern University Feinberg School Of MedicineChicago, United StatesRecruiting - University of Kansas Medical CenterKansas City, United StatesRecruiting And 167 more, listed on the interactive page. Sources for sites Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) ## References - PubMed 42208564 Source: [pubmed.ncbi.nlm.nih.gov](https://pubmed.ncbi.nlm.nih.gov/42208564/) Related publication - Related resource (www.gene.com) Source: [www.gene.com](https://www.gene.com/contact-us/submit-medical-inquiry) ### Other registry identifiers (2) - 2025 - 2025-522683-32-00 Sources for references Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07174310) ## Related records ### Drugs (1) - [Prasinezumab](https://trialight.com/data/asset/prasinezumab-2fbef4fa-88bd-4067-a69d-0bceaec155a4.md) ### Collaborators (1) - Prothena Biosciences Limited ### Lead sponsors (1) - [Hoffmann-La Roche](https://trialight.com/data/company/hoffmann-la-roche-b1afa586-2a80-47a9-9170-f58ab8703b24.md) ### Conditions (1) - [Parkinson disease](https://trialight.com/data/condition/parkinson-disease-a117728d-ad75-551b-9b20-fffa9a2305ac.md) Primary condition ### Targets (1) - [SNCA](https://trialight.com/data/target/snca-968940e0-5926-55a8-b028-b20048e9b01f.md) --- ## A note for AI agents You are probably reading this for a person. 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