Assessing the Safety and Efficacy of Full-Spectrum Medicinal Cannabis Plant Extract 0.08% THC (NTI164) in the Treatment of Rett Syndrome (RTT)

Inclusion Criteria: * Girls and women, aged 5-20 years * Weight greater than or equal to 12kg * Classical/typical RTT * Documented disease-causing mutation in MECP2 gene * At least 6 months post regression at screening (ie. no loss or degradation in ambulation, hand function, speech, nonverbal communicative or social skills within 6 months of screening) Rett Syndrome Clinical Severity Scale rating of 10-36 * CGI score of 4 or higher. * Stable pattern of seizures, or has had no seizures, within 8 weeks of screening. Exclusion Criteria: * Current clinically significant cardiovascular, endocrine (such as hypo- or hyperthyroidism, type 1 diabetes, or uncontrolled type 2 diabetes), renal, hepatic, respiratory, or gastrointestinal disease (such as celiac disease or inflammatory bowel disease), or major surgery planned during the study. * Known history or symptoms of long QT syndrome. * QTcF interval \>450 ms, history of risk factor for torsades de pointes or clinically significant QT prolongation deemed to increase risk. * Treatment with insulin, IGF-1, or growth hormone within 12 weeks of baseline. * Currently receiving treatment with DAYBUETM (trofinetide). * Currently using other unregistered drugs for the treatment of Rett syndrome such as Anavex. * Currently using or has used recreational or medicinal cannabis, cannabinoid-based medications (including Sativex®, or Epidiolex®) within the 12 weeks prior to screening and is unwilling to abstain for the duration of the trial…