First-in-Human Study of ALN-SNCA in Adult Participants With Early Parkinson's Disease (PD)

NCT ID: NCT07216066

Last Updated: 2026-01-29

Basic Information

• Recruitment Status: RECRUITING
• Clinical Phase: PHASE1
• Total Enrollment: 46 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2025-12-05
• Study Completion Date: 2029-06-07

Brief Summary

This study is researching an experimental drug called ALN-SNCA (called "study drug"). The study is focused on people with early Parkinson's disease, a disorder of the nervous system that affects movement. Parkinson's disease is caused by a gradual loss of nerve cells in the brain, especially those due to the harmful build-up of a protein called α-synuclein.

The aim of the study is to see if the study drug is safe and tolerated well enough to continue testing it in future studies and what side effects may happen from taking the study drug.

The study is looking at several other research questions, including:

• Whether the study drug can lower the level of α-synuclein protein in the Cerebrospinal Fluid (also referred to as "CSF", the fluid that surrounds the brain and spinal cord)
• How much study drug is in the blood, urine, and CSF at different times
• Compatible research to better understand the study drug (ALN-SNCA) and Parkinson's disease, including (but not limited to), whether the study drug can slow down the progression of Parkinson's disease symptoms

Conditions

Parkinsons Disease

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: SEQUENTIAL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: QUADRUPLE

Study Groups

ALN-SNCA Dose Escalation

Group Type: EXPERIMENTAL

ALN-SNCA

Intervention Type: DRUG

Administered per the protocol

Matching Placebo

Group Type: PLACEBO_COMPARATOR

Placebo

Intervention Type: DRUG

Administered per the protocol

Interventions

ALN-SNCA

Administered per the protocol

Intervention Type: DRUG

Placebo

Administered per the protocol

Intervention Type: DRUG

Eligibility Criteria

Inclusion Criteria

1. Diagnosis of Parkinson's disease according to the Movement Disorder Society (MDS) criteria, as assessed by the investigator, with bradykinesia plus at least one of the other cardinal signs of Parkinson's disease (resting tremor, rigidity), without any other known or suspected cause of Parkinsonism

2. A diagnosis of Parkinson's disease for 4 years or less at the screening visit

3. Participant must meet one of the following criteria:

1. Currently not receiving any standard-of-care (SoC) therapy for Parkinson's disease, has not been on oral dopaminergic therapy (ie, levodopa, dopamine agonists, or Monoamine Oxidase B [MAO-B] inhibitors) prior to dosing, and is not anticipated to require SoC therapy for Parkinson's disease within approximately 6 months following dosing, or

2. Has been on a stable regimen of oral dopaminergic therapy for at least 3 months prior to dosing and is not anticipated to require dose adjustments within approximately 6 months following dosing

4. BMI ≤35 kg/m^2 at time of screening visit

Exclusion Criteria

1. Medical history indicating a Parkinsonian syndrome other than Parkinson's disease, as defined in the protocol

2. Clinically significant cardiovascular, respiratory, hepatic, renal, gastrointestinal, endocrine, hematological, psychiatric or neurological disease (excluding Parkinson's disease) that, as assessed by the investigator, may confound the results of the study or pose an additional risk to the participant during study participation

3. Medical history of brain or spinal disease/injury that would interfere with the Lumbar Puncture (LP) procedure or CSF circulation, as defined in the protocol

4. Any contraindications to undergo a brain Magnetic Resonance Imaging (MRI)

5. An established allergy or intolerance to lidocaine anesthetic, as defined in the protocol

6. History of intolerance to Intrathecal (IT) injection(s)

7. Current history of bleeding diatheses that would increase risk of bleeding upon LP

8. Has undergone gene therapy, cell therapy or surgical treatment, including deep brain stimulation, for Parkinson's disease

• Minimum Eligible Age: 50 Years
• Maximum Eligible Age: 80 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Regeneron Pharmaceuticals

INDUSTRY

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Clinical Trial Management

Role: STUDY_DIRECTOR

Regeneron Pharmaceuticals

Locations

Center for Human Drug Research

Leiden, South Holland, Netherlands

Site Status: RECRUITING

Countries

Netherlands

Central Contacts

Clinical Trials Administrator

Role: CONTACT

clinicaltrials@regeneron.com

844-734-6643

Other Identifiers

2025-521431-37-00

Identifier Type: CTIS

Identifier Source: secondary_id

ALN-SNCA-PD-2482

Identifier Type: -

Identifier Source: org_study_id