NCT06393712 · Alnylam Pharmaceuticals
A Phase 2 Trial of ALN-APP in Patients With Cerebral Amyloid Angiopathy
(cAPPricorn-1)
What this study is about
The purpose of the study is to evaluate the effect of ALN-APP on measures of CAA disease progression and to characterize the safety, tolerability, and how the drug affects the body (PD) of ALN-APP in adult patients with sporadic CAA (sCAA) and Dutch-type CAA (D-CAA).
View original scientific description
The purpose of the study is to evaluate the effect of ALN-APP on measures of CAA disease progression and to characterize the safety, tolerability, and pharmacodynamics (PD) of ALN-APP in adult patients with sporadic CAA (sCAA) and Dutch-type CAA (D-CAA). The study will be conducted over 2 periods: a 24-month double-blind treatment period and an optional 18-month open-label extension (OLE) period.
Interventions
DRUG
Placebo
Placebo will be administered intrathecally
DRUG
ALN-APP
ALN-APP will be administered intrathecally
Primary outcome measures
Double-blind Treatment Period: Annualized Rate of New Lobar Cerebral Microbleeds (CMBs) Assessed on Magnetic Resonance Imaging (MRI) of Brain in Patients with Sporadic Cerebral Amyloid Angiopathy (sCAA)
Time frame: Up to 24 months
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- (sporadic CAA patients):
- Is 50 years or older
- Has probable CAA per the Boston Criteria Version 2.0 Inclusion Criteria (Dutch-type CAA patients):
- Is 30 years or older
- Has known E693Q amyloid precursor protein (APP) gene mutation for Dutch-type CAA
Exclusion criteria
- Moderate or severe stage Alzheimer's disease (AD) or significant cognitive impairment (CI)
- Has a history of previous clinical intracerebral hemorrhage (ICH) with onset less than 90 days prior to anticipated randomization in the study
- Has alanine aminotransferase (ALT) or aspartate aminotransferase (AST) \>3×upper limit of normal (ULN) at Screening
- Has estimated glomerular filtration rate (eGFR) \<30 mL/min/1.73m\^2 at Screening
- Has recently received an investigational agent
- Has had treatment with amyloid-targeting antibody Note: other protocol defined inclusion / exclusion criteria apply
Where
- Los Angeles, California
- Orange, California
- Palo Alto, California
- Sacramento, California
- San Francisco, California
- Aurora, Colorado
- New Haven, Connecticut
- Gainesville, Florida
- Jacksonville, Florida
- Maitland, Florida
- Naples, Florida
- Chicago, Illinois
And 18 more locations — see the full list below.
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Jul 15, 2026 · Source of record for eligibility and locations