A Study to Evaluate ALN-HTT02 in Adult Patients With Huntington's Disease

A Randomized, Double-blind, Placebo-controlled Study, to Evaluate the Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of Intrathecally Administered Single Ascending Doses of ALN-HTT02 in Adult Patients With Huntington's Disease

Status

Recruiting

Phases

Phase 1

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT06585449

Enrollment

Registered

2024-09-05

Start date

2024-10-14

Completion date

2028-07-05

Last updated

2026-09-16

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Huntington's Disease

Keywords

siRNA, ALN-HTT02, Intrathecal, HD-ISS Stage 2, HD-ISS early Stage 3, Neurodegenerative disorder

Brief summary

The purpose of this study is to evaluate the safety, tolerability, pharmacodynamics (PD) and pharmacokinetics (PK) of single or repeat doses of ALN-HTT02.

Interventions

DRUGALN-HTT02

ALN-HTT02 will be administered intrathecally

DRUGPlacebo

Placebo will be administered intrathecally

Study design

Allocation

RANDOMIZED

Intervention model

PARALLEL

Primary purpose

TREATMENT

Masking

TRIPLE (Subject, Caregiver, Investigator)

Eligibility

Sex/Gender

ALL

Age

25 Years to 70 Years

Healthy volunteers

Inclusion criteria

* Has stage 2 or early Stage 3 Huntington's disease (HD), per the Huntington's Disease Integrated Staging System (HD-ISS)

Exclusion criteria

* Has significant structural or degenerative neurologic disease other than Huntington's Disease (HD) at screening * Has primary or secondary immune compromise at screening due to infections, medical conditions, or chronic therapies * Has alanine aminotransferase or aspartate aminotransferase \>2× upper limit of normal (ULN) * Has an estimated glomerular filtration rate (eGFR) of \<60 mL/min/1.73m\^2 at screening * Has received an investigational agent within the last 1 year or 5 half-lives (if known) Note: other protocol defined inclusion /

Design outcomes

Primary

Measure	Time frame
Frequency of Adverse Events (AEs) in the Double-blind Part of the Study	Up to 12 months
Frequency of AEs in the Open-label Part of the Study	Up to 12 months
Frequency of AEs in the OLE Part of the Study	Up to 36 months

Secondary

Measure	Time frame	Description
Change from Baseline in Levels of Mutant Huntingtin (mHTT) in Cerebrospinal Fluid (CSF)	Baseline up to Month 12 in the Double-blind Part of the study; Baseline up to Month 12 in the Open-label Part of the study ; Baseline up to Month 36 in the OLE Part of the study	—
Concentrations of ALN-HTT02 in Plasma	Up to Month 12 in the Double-blind Part of the study; Up to Month 12 in the Open-label Part of the study; Up to Month 36 in the OLE Part of the study	Area Under the Plasma Concentration-time Curve (AUC) Maximum Observed Plasma Concentration (Cmax) Time to Maximum Plasma Concentration (Tmax)
Concentrations of ALN-HTT02 in Cerebrospinal Fluid (CSF)	Up to Month 12 in the Double-blind Part of the study; Up to Month 12 in the Open-label Part of the study ; Up to Month 36 in the OLE Part of the study	—
Concentrations of ALN-HTT02 in Urine	Up to Month 12 in the Double-blind Part of the study; Up to Month 12 in the Open-label Part of the study; Up to Month 36 in the OLE Part of the study	Fractional Excretion of ALN-HTT02

Countries

Canada, Germany, United Kingdom

Contacts

CONTACTAlnylam Clinical Trial Information Line

clinicaltrials@alnylam.com1-877-ALNYLAM

STUDY_DIRECTORMedical Director

Alnylam Pharmaceuticals

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Sep 17, 2026