A Study to Compare the Efficacy and Safety of Prasinezumab with a placebo in Participants with Early-Stage Parkinson’s Disease

Overview

Sponsor-declared trial summary

Key facts

Sponsor

F. Hoffmann-La Roche AG

Participant type

Patients

Age range

18-64 years, 65+ years

Gender

Male and Female

Therapeutic area

Diseases [C] - Nervous System Diseases [C10]

Trial duration

15 Jan 2026 → ongoing

Decision date (initial)

2025-12-29

Transition trial

No

Low-intervention

No

Rare-disease indication

No

Vulnerable population

Yes

Funding sources

F. Hoffmann-La Roche AG

Trial design

CTIS Part I — objectives, methods, condition coding

Main objective

Scope: Efficacy, Others, Safety, Pharmacokinetic

To evaluate the efficacy of prasinezumab compared with placebo

Secondary objectives 5

1. To evaluate the efficacy of prasinezumab compared with placebo with respect to change in motor function from baseline at Week 104, as measured by the Movement Disorder Society - Unified Parkinson's Disease Rating Scale (MDS-UPDRS) Part III off medication score, time to worsening of participants’ motor function as reported by the participant in the presence of a confirmed motor progression event, time to meaningful worsening in Clinician Global Impression of Change (CGI-C), Overall Disease Subscale and time to increase in LEDD
2. To evaluate the safety of prasinezumab compared with placebo (in participants on stable symptomatic monotherapy with levodopa, irrespective of their increase in LEDD during the study, and study treatment discontinuation)
3. To further characterize PK of prasinezumab
4. To further evaluate the immunogenicity of prasinezumab
5. Open-Label Extension Objectives: To evaluate long-term safety and tolerability of prasinezumab in participants with early-stage PD that have completed the double-blind treatment period of the study

Conditions and MedDRA coding

Early-Stage Parkinson’s Disease (PD)

Regulatory references

Scientific advice from competent authorities

European Medicines Agency

Plan to share IPD

No

IPD plan description

NA

Eligibility criteria

Principal inclusion / exclusion criteria as submitted by sponsor

Inclusion criteria 5

1. Diagnosis of idiopathic PD based on Movement Disorder Society (MDS) criteria (Postuma et al. 2015) with bradykinesia plus one of the other cardinal signs of PD (resting tremor, rigidity), without any other known or suspected cause of parkinsonism
2. Has received PD medication for at least 3 months prior to baseline
3. An MDS-UPDRS Part IV score of 0 at screening and prior to randomization
4. Hoehn and Yahr (H&Y) Stage 1 or 2 off medication at screening and prior to randomization
5. Agreement to adhere to the contraception requirements

Exclusion criteria 4

1. Pregnant or breastfeeding, or intention of becoming pregnant during the study or within the time frame in which contraception is required Participants of childbearing potential must have a negative serum pregnancy test result during screening prior to initiation of study treatment
2. Medical history indicating a parkinsonian syndrome other than idiopathic PD
3. Diagnosis of a significant neurological disease other than PD
4. Uncontrolled hypertension

Endpoints

Primary and secondary outcome measures (English text)

Primary endpoints 1

1. Time to a confirmed motor progression event on MDS‑UPDRS Part III score from the randomization date

Secondary endpoints 14

1. Change in motor function from baseline at Week 104, as measured by the MDS-UPDRS Part III off medication score
2. Time to worsening of participants’ motor function as reported by the participant in the presence of a confirmed motor progression event
3. Time to meaningful worsening in CGI-C, Overall Disease Subscale
4. Time to increase in LEDD
5. Nature, incidence, seriousness and severity of adverse events, with severity determined according to the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE) v5.0
6. Incidence of adverse events of special interest
7. Incidence of treatment discontinuation due to adverse events
8. Nature, incidence, seriousness, severity and timing of IRRs
9. Mean change in vital signs from baseline over time and incidence of abnormal vital sign measurements
10. Nature and incidence of abnormal ECG assessments
11. Change from baseline, shift tables, and incidence of laboratory abnormalities (including hematology, clinical chemistry, coagulation, and urinalysis parameters)
12. Summary statistics of participants with suicidal ideation or behavior as assessed by Columbia Suicide Severity Rating Scale (C-SSRS) score, including detailed focus on any individual cases identified as having severe ideation or behavior during the study conduct
13. Serum concentration of prasinezumab or PK parameters at specified timepoints
14. Prevalence of anti-drug antibodies (ADAs) at baseline and incidence of ADAs during the study

Investigational products

Investigational medicinal products (IMPs), comparators, placebo, auxiliary

Test 1

Placebo 1

Sponsors and contacts

Sponsor organisations, regulatory contacts, third parties

F. Hoffmann-La Roche AG

Sponsor organisation

F. Hoffmann-La Roche AG

Address

Grenzacherstrasse 124

City

Basel

Postcode

4058

Country

Switzerland

Scientific contact point

Organisation

F. Hoffmann-La Roche AG

Contact name

Trial Information System - TISL

Public contact point

Organisation

F. Hoffmann-La Roche AG

Contact name

Trial Information System - TISL

Third parties 7

Locations

9 EU/EEA countries · 84 investigational sites

By country

Investigational sites

Country notifications

Trial-start, recruitment-start, end and early-termination notifications submitted per Member State

Results and documents

Annex IV summary of results, Annex V layperson summary, and all documents registered in CTIS for this trial

Documents 97 files

Public protocol annexes, IB summaries, regulatory submissions and post-authorisation documents registered in CTIS.

Application history

5 submissions — initial application plus substantial / non-substantial modifications