NCT06662188 · Jaguar Gene Therapy, LLC
JAG201 Gene Therapy Study in Children & Adults With SHANK3 Haploinsufficiency
What this study is about
This is a Phase 1/2, first in human, where both patients and doctors know the treatment given, gradually increasing doses study to evaluate the safety, tolerability, and clinical activity of a single dose of JAG201 administered via intracerebroventricular (ICV) injection in pediatric and adult participants with SHANK3 haploinsufficiency resulting from SHANK3 loss of function mutations and chromosomal deletions encompassing the SHANK3 gene. Clinical data will be evaluated for safety, tolerability, and preliminary clinical activity of JAG201 in pediatri
View original scientific description
This is a Phase 1/2, first in human, open-label, dose-escalation study to evaluate the safety, tolerability, and clinical activity of a single dose of JAG201 administered via intracerebroventricular (ICV) injection in pediatric and adult participants with SHANK3 haploinsufficiency resulting from SHANK3 loss of function mutations and chromosomal deletions encompassing the SHANK3 gene.
Interventions
GENETIC
JAG201
Adeno-associated virus 2/9 expressing a miniature version of the human SHANK3 gene (AAV2/9-miniSHANK3)
GENETIC
JAG201
Adeno-associated virus 2/9 expressing a miniature version of the human SHANK3 gene (AAV2/9-miniSHANK3)
Primary outcome measures
Incidence of Adverse Events (AEs)
Time frame: Enrollment to Month 60
Incidence, type, severity, and frequency of AEs
Incidence of Serious Adverse Events (SAEs)
Time frame: Enrollment to Month 60
Incidence, type, severity, and frequency of SAEs
Clinically significant abnormalities in laboratory values
Time frame: Enrollment to Month 60
Changes in clinically significant abnormalities in laboratory values
Incidence of immunogenicity response abnormalities
Time frame: Enrollment to Month 60
Incidence of anti-AAV9 antibodies, anti-transgene antibodies, and T-cell reactivity to transgene over time
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
- Is male or female, and 2 to 9 years of age at the time of JAG201 administration 2. Has a molecular confirmation of a loss of function mutation in SHANK3 or a 22q13.3 deletion classified as a Class I deletion 3. Has evidence of developmental/cognitive delay of at least 2 standard deviations (SD) below the mean (i.e., \< 70) via either Intelligence Quotient (IQ) OR Developmental Quotient (DQ) assessment (as applicable) 4. Has an overall Phelan-McDermid Syndrome (PMS)-specific Clinical Global Impression-Severity (CGI-S) Score of 3 or greater at Screening 5. Willing to initiate structured therapies and continue for the duration of the study as determined by the specific therapist (structured therapies may include, at a minimum, physical therapy, occupational therapy, speech therapy, and applied behavior analysis) 6. Is stable on any medication regimens (if being administered to control the signs and symptoms of underlying disease) for at least 3 months prior to
Where
- Chicago, Illinois
- Boston, Massachusetts
- New York, New York
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 Feb 9, 2026 · Source of record for eligibility and locations