NCT07378644 · Skyhawk Therapeutics, Inc.
Study to Evaluate the Pharmacodynamics, Safety and Efficacy of SKY-0515 in Participants With Huntington's Disease
(FALCON-HD)
What this study is about
The goal of this clinical trial is to test if the drug SKY-0515, an taken by mouth medication, can lower harmful proteins linked to Huntington's Disease (HD) and improve the symptoms of participants with HD. This study includes men and women aged 25 and older who have HD confirmed by genetic testing and meet certain requirements for physical ability and independence.
View original scientific description
The goal of this clinical trial is to test if the drug SKY-0515, an oral medication, can lower harmful proteins linked to Huntington's Disease (HD) and improve the symptoms of participants with HD. This study includes men and women aged 25 and older who have HD confirmed by genetic testing and meet certain requirements for physical ability and independence.
Interventions
DRUG
SKY-0515
Type: Small molecule Dosage Level(s): Low, mid, high Route of Administration: Oral Dosage Frequency: Once daily Blinded Treatment Duration: 18 months Use: Experimental
DRUG
SKY-0515 Placebo
Route of Administration: Oral Dosage Frequency: Once daily Blinded Treatment Duration: 18 months Use: Experimental
Primary outcome measures
Change From Baseline in the Z-score from the Composite Unified Huntington's Disease Rating Scale (cUHDRS)
Time frame: 72 weeks
cUHDRS includes the Total Functional Capacity (range, 0-13; higher score means better functioning), Total Motor Score (range, 0-124; higher score means worse motor severity), Symbol Digit Modality Test (range, 0-110, correctly paired numbers-symbols in 90 seconds; higher score means better cognitive performance), and Stroop Color and Word Test (range, 0-no max value, correctly read color words in 45 seconds; higher score means better cognitive performance) scores. A z-score for each test is calculated, which alone can be used to describe relationship between an individual's test score and the mean score of a target population. A z-score of 0 is the mean, and ±1 is 1 standard deviation from the mean. For cUHDRS, z-scores of each test are summed, whereby a higher cUHDRS score is better (score of -3.06-no max value) and a change of ≥1.2 is a meaningful worsening, shown to track functional decline.
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
- 25 years or older.
- Huntington's Disease confirmed through genetic testing, with a specific change in exon 1 of the HTT gene (CAG repeat of 40 or more).
- Total Functional Capacity (TFC) score of 10 or more).
- Total Motor Score (TMS) of 6 or more).
- Independence Score (IS) of 70 or more).
- Women who can have children must have a negative pregnancy test before starting and use two types of birth control during the study and for 30 days after the last dose of the study drug.
- Men must agree to use birth control during the study and for 90 days after the last dose.
- Agree to sign a consent form and follow the study's rules and schedule.
Exclusion criteria
- Other Serious health problems or brain/spinal issues that could interfere with the study or make procedures unsafe.
- Conditions that interfere with protocol-specified assessments, like an implanted medical device or difficulty getting an MRI.
- Cancer, except for some types of skin cancer, or a history of cancer in the last five years.
- Severe allergies or have reacted badly to similar drugs in the past.
- Taking medications or treatments that might interfere with the study.
- Participated in another study or taken experimental drugs in the last two months (or longer for some drugs).
- Any kind of gene therapy.
- History of suicidal thoughts, severe depression, or have attempted suicide in the past year.
- Liver function tests show significant abnormalities.
- Positive for hepatitis B, hepatitis C, or HIV.
- Pregnancy, breastfeeding, or planning to become pregnant during the study.
Where
- Englewood, Colorado
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 Aug 25, 2026 · Source of record for eligibility and locations