A Study of RG1662 in Adults and Adolescents With Down Syndrome (CLEMATIS)

This study is ongoing, but not recruiting participants.
Information provided by (Responsible Party):
Hoffmann-La Roche
ClinicalTrials.gov Identifier:
First received: December 27, 2013
Last updated: November 2, 2015
Last verified: November 2015
This multi-center, randomized, double-blind, 3-arm, parallel-group, placebo-controlled study will evaluate the efficacy and safety of RG1662 in adults and adolescents with Down syndrome. Subjects will be randomized to receive RG1662 either at low or high dose or placebo orally twice daily for 26 weeks.

Condition Intervention Phase
Down Syndrome
Drug: Placebo
Drug: RG1662
Phase 2

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Investigator)
Primary Purpose: Treatment

Resource links provided by NLM:

Further study details as provided by Hoffmann-La Roche:

Primary Outcome Measures:
  • Cognition as assessed by the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) sub-tests [ Time Frame: 26 weeks ] [ Designated as safety issue: No ]
  • Adaptive behavior as assessed by the Vineland Adaptive Behavior Scales-II (VABS-II) standard scores [ Time Frame: 26 weeks ] [ Designated as safety issue: No ]
  • Clinical global impression as assessed by Clinician Rated Global Improvement (CGI-I) scale [ Time Frame: 26 weeks ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • Incidence of abnormal ECG changes [ Time Frame: 26 weeks ] [ Designated as safety issue: No ]
  • Abnormal ECG changes in adolescents as compared to baseline [ Time Frame: from baseline to Week 26 ] [ Designated as safety issue: No ]
  • Safety: Incidence of adverse events [ Time Frame: approximately 32 weeks ] [ Designated as safety issue: No ]
  • Incidence of abnormal blood pressure [ Time Frame: 26 weeks ] [ Designated as safety issue: No ]
  • RG1662 plasma concentrations [ Time Frame: 26 weeks ] [ Designated as safety issue: No ]

Enrollment: 173
Study Start Date: May 2014
Estimated Study Completion Date: May 2016
Estimated Primary Completion Date: May 2016 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Placebo Comparator: Placebo Drug: Placebo
Orally twice daily, 26 weeks
Experimental: RG1662 120 mg bid Drug: RG1662
120 mg (80 mg for subjects 12 and 13 years of age) orally twice daily, 26 weeks
Experimental: RG1662 240 mg bid Drug: RG1662
240 mg (160 mg for subjects 12 and 13 years of age) orally twice daily, 26 weeks


Ages Eligible for Study:   12 Years to 30 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Individuals aged 12-30 years of age inclusive
  • Clinical diagnosis of Down syndrome (trisomy 21) confirmed by chromosomal analysis (karyotyping)
  • Males, or non-pregnant, non-lactating females. For females of childbearing potential, strict contraceptive prevention is required.
  • Body-mass Index (BMI) 18-42 and 15-30 kg/m2 inclusive for adults and adolescents respectively
  • Ability to complete the Clinical Evaluation of Language Fundamentals (CELF)-preschool 2 word classes task
  • Subjects must have a parent, or other reliable caregiver who agrees to accompany the subject to all clinic visits, provide information about the subject as required by the protocol, and ensure compliance with the medication schedule
  • Study participants must have sufficient language, vision and hearing to participate in study evaluations, as judged clinically by investigator

Exclusion Criteria:

  • Subjects with a current DSM 5 diagnosis of any primary psychiatric diagnosis (including ASD or MDD)
  • Subjects with a history of infantile spasms, of West syndrome, Lennox-Gastaut syndrome, Early Infantile Epileptic Encephalopathy or any treatment-refractory epilepsy associated with cognitive or developmental regression, of severe head trauma or CNS infections (e.g. meningitis)
  • Subjects with a known or suspected clinical seizure event of any type within 24 months prior to screening
  • Clinically relevant ECG abnormalities at screening or baseline; QTcF above 450 ms; personal or family history (first degree relatives) of congenital long QT syndrome
  • Inadequate renal or hepatic function
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT02024789

  Show 37 Study Locations
Sponsors and Collaborators
Hoffmann-La Roche
Study Director: Clinical Trials Hoffmann-La Roche
  More Information

No publications provided

Responsible Party: Hoffmann-La Roche
ClinicalTrials.gov Identifier: NCT02024789     History of Changes
Other Study ID Numbers: BP27832, 2013-001263-23
Study First Received: December 27, 2013
Last Updated: November 2, 2015
Health Authority: United States: Food and Drug Administration

Additional relevant MeSH terms:
Down Syndrome
Abnormalities, Multiple
Chromosome Disorders
Congenital Abnormalities
Genetic Diseases, Inborn
Intellectual Disability
Nervous System Diseases
Neurobehavioral Manifestations
Neurologic Manifestations
Pathologic Processes

ClinicalTrials.gov processed this record on November 27, 2015