Pharmacological Treatment of Rett Syndrome With Glatiramer Acetate (Copaxone)

A phase 2 open label trial to test a potential drug treatment for Rett syndrome, the leading known genetic cause of severe neurological impairment in girls. The drug, Copaxone (generic name - Glatiramer acetate) is medication FDA approved for the treatment of multiple sclerosis. Copaxone's high safety profile has been documented in large cohorts of patients for more than 12 years.

Background/rationale for the study: In Rett syndrome brain cells aren't actually lost, instead poor maturation of connections between brain cells (synapses) prevents effective neurological functioning, and is the main morphological feature of the disease. The MeCP2 gene plays a major role in transcriptional regulation of other genes, one of which is the gene encoding brain-derived neurotrophic factor (BDNF). The disease progression and severity of symptoms is directly affected by the level of BDNF expression. An increase of BDNF levels (by genetic manipulations or pharmacological agents) leads to delayed onset of Rett syndrome-like symptoms in experimental models; rescued gait/mobility, improved quality of life and increased survival rates. Copaxone treatment by subcutaneous injection caused elevation of BDNF levels. Quantitative immunofluorescence assays showed about a twofold increase in neuronal expression of BDNF following Copaxone treatment. We expect that an increase in BDNF levels with Copaxone administration will stimulate communication between brain cells (synaptic maturation), which will lead to amelioration of symptoms (motor functions/gait, cognitive functions, breathing, encephalopathy and improve quality of life) for girls with Rett syndrome.

Dose escalation: Study drug will be administered once a week for 4 weeks, twice a week for 4 weeks and daily for 24 weeks. Drug is administered as a subcutaneous injection.

To perform quantitative gait assessments a computerized walkway (457 × 90.2 × 0.64cm) with embedded pressure sensors (GAIT Rite system) was used. Subjects walked on the walkway for two trials, while wearing comfortable footwear.

Breath hold index is defined as number of breath holds/hour. Respirations were monitored with sleep monitoring equipment during the daytime at the polysomnography laboratory with additional oronasal airflow, electromyography (EMG), EEG and video monitoring to confirm wakefulness during the period of study.

Breath Hold Time is defined as percentage of time spent holding the breath in a specific time unit. It is measured by a standard medical technique where belts are placed on the chest and abdomen to record movement and sensors are used to record nasal flow. Wake respiration was monitored with sleep monitoring equipment during the daytime at the polysomnography laboratory with additional oronasal airflow, EMG, EEG and video monitoring to confirm wakefulness during the period of study.

Eye-tracking is considered an indication of visual memory. Eye-tracking data was recorded at 300 Hz sampling rate using a Tobii T300 computer (Tobii Technology, Danderyd, Sweden). The actual data given by the computer represents the percentage of time spent looking at a novel visual target - this is called the novelty score. Visual memory, as indexed by the novelty score, is the percentage of time spent looking at a novel target during the test ("visual paired comparison paradigm"). Duration of testing was 2 minutes.

Visual attention is indexed by duration and number of fixations on novel target on testing. The standard method of assessing visual attention in neuropsychology is by measuring: A)number of fixations (how many times the subject looks at each of the 2 visual targets). The higher number of fixations, the more attentive the subject to that visual target. B) duration of fixations in seconds (the longer the fixation the more attentive). Duration of fixations correlates with intelligence: the smarter the person is the shorter his fixations are. Eye-tracking data was recorded at 300 Hz sampling rate using a Tobii T300 (Tobii Technology AB, Danderyd, Sweden). The measured index is called the Novelty Score which indicates the percentage of time spent looking at novel visual target. Duration of testing session was 2 minutes.

The standard method of assessing visual attention in neuropsychology is by measuring: A)number of fixations (how many times the subject looks at each of the 2 visual targets). The higher number of fixations, the more attentive the subject to that visual target. B) duration of fixations in seconds (the longer the fixation the more attentive). Duration of fixations correlates with intelligence: the smarter the person is the shorter his fixations are. Eye-tracking data was recorded at 300 Hz sampling rate using a Tobii T300 (Tobii Technology AB, Danderyd, Sweden). The measured index is called the Novelty Score which indicates the percentage of time spent looking at novel visual target. Visual attention is indexed by number of fixations on novel target on test. Duration of testing session was 2 minutes.

Inclusion Criteria: Female patients with genetically confirmed Rett Syndrome (RTT) Age: 10 or more years old. Selection of the age is based on the available evidence of the safety of Glatiramer Acetate (GA) in this group, and the relative homogeneity/stability of the phenotype, which is not expected to spontaneously change within a 6 month period at this age Ambulatory (with our without support) Exclusion Criteria: Prolonged Qtc (obtained within 30 days prior to enrollment) Presence of co morbid non-Rett related disease Presence of immunodeficiency requiring intravenous immunoglobulin 3 (IVIG 3) months prior to enrollment Allergy/sensitivity to GA or mannitol Inability or unwillingness of legal guardians to give written informed consent

Djukic A, Holtzer R, Shinnar S, Muzumdar H, Rose SA, Mowrey W, Galanopoulou AS, Shinnar R, Jankowski JJ, Feldman JF, Pillai S, Moshe SL. Pharmacologic Treatment of Rett Syndrome With Glatiramer Acetate. Pediatr Neurol. 2016 Aug;61:51-7. doi: 10.1016/j.pediatrneurol.2016.05.010. Epub 2016 May 27.