Comparison Between [11C]UCB-J and [18F]SynVest-1 PET in HD.

Eligibility criteria

Inclusion Criteria:
1. Healthy controls (n = 10-20)
   * Subject is judged to be in good health by the investigator on the basis of medical history, physical examination including vital signs, clinical laboratory test and urinalysis.
   * No history or evidence of current major neurological, internal or psychiatric disorder, based on the medical assessment as described hereabove and neuropsychological assessment.
   * In subjects \< 60 years of age, an unremarkable structural MRI scan as assessed by expert radiologist. In subjects >= 60 years of age white matter hyperintensities corresponding to a white matter lesion (WML) Fazekas score \< 2 on the Age-Related White Matter changes scale are acceptable.
2. HD-ISS stage 3 HD mutation carriers (n = 10)
   * HTT CAG repeat expansion 40 - 50
   * stage 3 as determined by the HD-ISS staging criteria
   * UHDRS TFC >/= 10
3. HD-ISS stage 2 HD mutation carriers (n = 10)
   * HTT CAG repeat expansion 40 - 50
   * stage 2 as determined by the HD-ISS staging criteria
   * PIN score 0.47 - 1.84
Exclusion Criteria:
* Neuropsychiatric diseases; for HD mutation carriers any neuropsychiatric diseases other than HD
* Major internal medical diseases
* White matter lesion load on FLAIR Fazekas score 2 or higher or other relevant MRI abnormalities
* History of alcohol abuse or current alcohol abuse (chronic use of more than 15 units per week) or drug use
* Contraindications for MR
* Subject suffers from claustrophobia or cannot tolerate confinement during PET-MRI scanning procedures; subject cannot lie still for 30 minutes inside the scanner.
* Subject is unwilling to avoid unusual, unaccustomed, or strenuous physical activity (i.e., weightlifting, running, bicycling) from the time of the pre-study visit until the end of scanning.
* Subject does not understand the study procedures or does not have a guardian who understands the study procedures.
* Subject (or guardian) is unwilling or unable to perform all of the study procedures or is considered unsuitable in any way by the principal investigator.
* Subject is on anticoagulant therapy.
* Subject is pregnant (according to Ulti Med hCG urine test) or breastfeeding.
* Subject is a woman of childbearing potential who does not agree to apply appropriate contraception methods during study participation and continues to do so for at least 6 months after study completion.
* Subject is a man with a pregnant or non-pregnant WOCBP partner, who does not agree to use a condom and continue to do so until 90 days after study completion. In addition, the non-pregnant WOCBP partner should use a highly effective method of contraception.

The sponsor's own eligibility wording, lightly reformatted. The study team makes the final eligibility decision — worth discussing with your doctor.

Eligibility criteria as of 2025-07-30