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A Study of the Safety and Tolerability of GTX-102 in Children with Angelman Syndrome

Phase 1
Completed
Conditions
Angelman Syndrome
Interventions
Registration Number
NCT04259281
Lead Sponsor
Ultragenyx Pharmaceutical Inc
Brief Summary

The primary objective of the study is to evaluate the safety and tolerability of multiple-ascending doses of GTX-102 administered by intrathecal (IT) injection to participants with Angelman Syndrome (AS).

Detailed Description

This is a Phase 1/2, open-label, multiple-dose, study to evaluate the safety, tolerability, and plasma and CSF concentrations of GTX-102 in pediatric participants with AS.

The study includes a Loading phase followed by a Maintenance phase. Participants may continue on GTX-102 during the Maintenance phase of the study until GTX-102 is commercially available, intolerable toxicity occurs, the parent/legal guardian withdraws consent, the participant enrolls in another experimental study, or this study is terminated.

This study was previously posted by GeneTX Biotherapeutics, LLC and was transferred to Ultragenyx in July 2022.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
74
Inclusion Criteria
  • Signed informed consent from parent(s) or legal guardian(s)
  • Documented genetic confirmation of full maternal UBE3A gene deletion causing AS in the region of 15q11.2-q13 including class I, II or III
  • Stable seizure control (defined as clinically stable with no changes in antiepileptic medications over the prior 1 month before the screening visit, other than weight associated dose adjustments)
  • Able to ambulate independently, or with an assistive device (note, a child whose primary means of mobility is by wheelchair is excluded from the study)
  • Platelet count, prothrombin time / international normalized ratio, and partial thromboplastin time within 1.2 x the normal limits
  • Normal renal function with serum creatinine and spot urine protein ≤ 1.4 x the upper limit of normal (ULN)
  • Normal hepatic function with total bilirubin, aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase ≤ 1.4 x ULN. Exception: levels ≤ 2 × ULN are acceptable if due to anti-epileptic drugs (AEDs) or Gilbert syndrome
  • Willing and able to comply with scheduled visits, drug administration plan, laboratory tests, study restrictions, and all study procedures, including LP procedure
  • Able to tolerate the anesthetic regimen, if required for LP procedure
  • A female patient is eligible to participate if she is not pregnant, not breastfeeding, and at least one of the following conditions applies: Female of non-childbearing potential (ie, pre-menarche), Female of childbearing potential who agrees to remain abstinent (refrain from heterosexual intercourse) or use acceptable contraceptive methods during the treatment period and for at least 3 months after the final dose of GTX-102
  • A male patient is eligible to participate if he agrees to remain abstinent (refrain from heterosexual intercourse) or use acceptable contraceptive methods during the treatment period and for at least 3 months after the final dose of GTX-102
Exclusion Criteria
  • Any change in medications (excluding AEDs) or diet/supplements intended to treat symptoms of AS (eg, sleeping aids, supplements, dietary change including ketogenic or low-glycemic index diet, other) over the prior 1 month before screening
  • Any bleeding or platelet disorder
  • Any clinically significant cardiovascular, endocrine, hepatic, renal, pulmonary, gastrointestinal, neurological, malignant, metabolic, psychiatric, or other condition that, in the judgment of the Investigator, will pose a safety risk, make the patient unsuitable for participation in, and/or unable to complete the study procedures
  • Any laboratory abnormality, that, in the Investigator's opinion, could adversely affect the safety of the patient, make it unlikely that the course of treatment or follow up would be completed, or impair the assessment of study result
  • Known positive for hepatitis B virus, hepatitis C virus, or human immunodeficiency virus
  • Any active infection
  • Bone, spine, bleeding, or other disorder that exposes the patient to risk of injury or unsuccessful lumbar puncture
  • Drugs that increase the risk of bleeding (eg, heparin, low molecular weight heparin, platelet inhibitors)
  • Any prior use of gene therapy
  • Use of any investigational drugs in the past 6 months or within 5 half-lives, whichever period is greater (with the exception of prior GTX 102)
  • Known hypersensitivity to any oligonucleotide, as demonstrated by an immune mediated reaction (eg, pneumonitis, hepatitis, nephritis, neuritis, or other system inflammation), or a systemic allergic reaction such as signs and symptoms of anaphylaxis, urticaria, clinically significant rash
  • Patient is pregnant or lactating
  • Any medical condition that would require intubation for the anesthesia procedure

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
GTX-102 Expanded Enrollment Cohort AGTX-102Sponsor selected dose followed by slow intra-patient dose escalation and then a maintenance phase (in Ex-U.S participants 4 to \<8 years of age)
GTX-102 Cohort EGTX-102Sponsor selected dose followed by slow intra-patient dose escalation and then a maintenance phase (in participants that transition from GTX-102 US Cohort only)
GTX-102 Cohort 2GTX-10210 mg starting dose followed by intra-patient dose escalation up to 36 mg and then a maintenance phase (in U.S participants 4 to \<17 years of age)
GTX-102 Cohort 4GTX-1023.3 mg starting dose followed by slow intra-patient dose escalation up to 5 mg and then a maintenance phase (in Ex-U.S participants 4 to \<8 years of age)
GTX-102 Cohort 7GTX-10210 mg starting dose followed by slow intra-patient dose escalation up to 12 mg and then a maintenance phase (in Ex-U.S participants ≥ 8 to 17 years of age)
GTX-102 Cohort USGTX-1022 mg for 4 monthly doses followed by a quarterly maintenance regimen
GTX-102 Expanded Enrollment Cohort BGTX-102Sponsor selected dose followed by slow intra-patient dose escalation and then a maintenance phase (in Ex-U.S participants ≥ 8 to 17 years of age)
GTX-102 Expanded Enrollment Cohort DGTX-102Sponsor selected dose followed by slow intra-patient dose escalation and then a maintenance phase (in U.S participants ≥ 8 to 17 years of age)
GTX-102 Cohort 1GTX-1023.3 mg starting dose followed by intra-patient dose escalation up to 36 mg and then a maintenance phase (in U.S participants 4 to \<17 years of age)
GTX-102 Cohort 3GTX-10220 mg starting dose followed by intra-patient dose escalation up to 55 mg and then a maintenance phase (in U.S participants 4 to \<17 years of age)
GTX-102 Cohort 5GTX-1025 mg starting dose followed by slow intra-patient dose escalation up to 7.5 mg and then a maintenance phase (in Ex-U.S participants ≥ 8 to 17 years of age)
GTX-102 Cohort 6GTX-1027.5 mg starting dose followed by slow intra-patient dose escalation up to 10 mg and then a maintenance phase (in Ex-U.S participants 4 to \<8 years of age)
GTX-102 Expanded Enrollment Cohort CGTX-102Sponsor selected dose followed by slow intra-patient dose escalation and then a maintenance phase (in U.S participants 4 to \<8 years of age)
Primary Outcome Measures
NameTimeMethod
Number of Participants with Adverse Events (AEs), Serious AEs (SAEs), Adverse Events of Special Interest (AESIs), AEs Leading to Discontinuation and Severity of AEsUp to Day 337
Secondary Outcome Measures
NameTimeMethod
Pharmacokinetics of GTX-102 over timeUp to Day 337

Maximum drug concentration (Cmax)

Trial Locations

Locations (25)

Rare Disease Research

🇺🇸

Atlanta, Georgia, United States

Rush University Medical Center

🇺🇸

Chicago, Illinois, United States

Boston Children's Hospital

🇺🇸

Boston, Massachusetts, United States

UCLA Medical Center

🇺🇸

Los Angeles, California, United States

Rady Children's Hospital

🇺🇸

San Diego, California, United States

Hopital de la Timone

🇫🇷

Marseille, France

Children's Hospital of Western Ontario

🇨🇦

London, Ontario, Canada

Queensland Children's Hospital

🇦🇺

South Brisbane, Australia

Cambridge University Hospitals

🇬🇧

Cambridge, United Kingdom

Hospital Universitari Parc Tauli

🇪🇸

Sabadell, Barcelona, Spain

AP-HP Hopital Necker-Enfants Malades

🇫🇷

Paris, France

Hospital Sant Joan de Deu

🇪🇸

Esplugues De Llobregat, Barcelona, Spain

Great Ormond Street Hospital for Children

🇬🇧

London, United Kingdom

Universitatsklinikum Leipzig

🇩🇪

Leipzig, Sachsen, Germany

Universitatsklinikum Hamburg-Eppendorf

🇩🇪

Hamburg, Germany

The Royal Children's Hospital

🇦🇺

Parkville, Victoria, Australia

Weill Cornell Medicine

🇺🇸

New York, New York, United States

McGill University Health Centre

🇨🇦

Montréal, Quebec, Canada

The Edmond and Lily Safra Children's Hospital

🇮🇱

Ramat Gan, Israel

Oxford University Hospitals NHS Foundation Trust

🇬🇧

Oxford, United Kingdom

MAGIC Clinic Ltd

🇨🇦

Calgary, Alberta, Canada

Austin Health

🇦🇺

Heidelberg, Victoria, Australia

British Columbia Children's Hospital

🇨🇦

Vancouver, British Columbia, Canada

Children's Hospital of Eastern Ontario

🇨🇦

Ottawa, Ontario, Canada

Hospital Universitario Puerta de Hierro

🇪🇸

Majadahonda, Madrid, Spain

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