Placebo

• Bionetide placebo solution administered based on the subject's weight at Baseline, twice daily for 12 weeks

The Impact of Childhood Neurologic Disability (ICND) scale evaluates the effect of four conditions or health problems on 11 aspects of a child's or family's life as "A lot", "Some", "A little", "Not at all", or "Does not apply". The four conditions or health problems are 1) inattentiveness, impulsivity, or mood, 2) ability to think and remember, 3) neurologic or physical limitations, and 4) epilepsy. The ICND score the range of 0 to 132 and a higher score represents a worse outcome.

Clinical assessment of the subject's ability to use their hands for functional purposes (such as reaching for and grasping objects, self-feeding, or drawing). The assessment is made on an 8-point Likert scale (0-7) with 0 denoting normal functioning and 7 the most severe impairment.

Clinical assessment of the subject's ability to sit, stand, and ambulate (e.g., walking, running, and climbing stairs). The assessment was made on an 8-point Likert scale (0 to 7), with 0 denoting normal functioning and 7 as the most severe impairment.

Clinical assessment of the subject's ability to communicate their choices or preferences, which can include the use of nonverbal means such as eye contact or gestures. The assessment is made on an 8-point Likert scale (0-7) with 0 denoting normal functioning and 7 the most severe impairment.

Clinical assessment of the subject's ability to communicate verbally (e.g. words and phrases). The assessment is made on an 8-point Likert scale (0-7) with 0 denoting normal functioning and 7 the most severe impairment.

A 7 point scale that rates the severity of the subject's illness at the time of assessment, relative to the clinician's experience with subjects who have the same diagnosis. A subject is assessed on severity of illness at the time of rating: 1, normal, not at all ill; 2, borderline ill; 3, mildly ill; 4, moderately ill; 5, markedly ill; 6, severely ill; or 7, extremely ill.

The Rett Syndrome Caregiver Burden Inventory (RTT-CBI) scale is intended to directly address caregiver burden and indirectly assess the significance of treatment effects on function in the context of activities of daily living. Ratings are on a 5-point Likert scale including: 0-never; 1-rarely; 2-sometimes; 3-frequently and 4-nearly always. As in the original Caregiver Burden Inventory, the RTT-CBI has 24 negatively worded items (items 1 through 24) yielding a total score up to 96. The RTT-CBI the range is 0 to 96 and a higher score represents a worse outcome.

The overall quality of life of the subject is also rated by responding to the following: "Please rate your child's overall 'Quality of Life' on the scale below. Choose the number which you feel is best and circle it." The choices range from 1 ("Poor") to 6 ("Excellent").