NTI164 · program

NTI164 for Rett syndrome

Phase 1/2ActiveNeurotech International Limited (NTI)

Indications for NTI164: Autism spectrum disorder · Phase 3 Rett syndrome · Phase 1/2

NTI164, an oral CBDA-rich full-spectrum low-THC cannabis extract, for Rett syndrome. An open-label Phase I/II study (NCT06621043) in 11 girls aged 5-16 with a pathogenic MECP2 variant, dosed twice daily for 12 weeks, reported improvement on the primary CGI-I measure and on the Rett Syndrome Behaviour Questionnaire, mood, anxiety, communication and quality-of-life measures, with NTI164 well tolerated; the study was uncontrolled. A Phase II/III double-blind, randomised, placebo-controlled crossover study (NCT07257978, 40 participants aged 4-25, primary endpoint RSBQ) is registered but not yet recruiting, with an estimated start of July 2027. In February 2026 Neurotech began a research collaboration with the University of Sydney to study NTI164's mechanism in human Rett neuronal models.

Data current as of

Development timeline

Phase 1/2Sept 2023 – Oct 2028
  1. UpcomingClinicalTrials.gov estimated primary completion of the Phase II/III placebo-controlled crossover study of NTI164 in Rett syndrome: October 2028 (not yet recruiting; estimated start July 2027).
  2. PartnershipNeurotech and the University of Sydney collaborate on NTI164 for Rett syndrome↗
  3. Trial registeredPhase II/III study of NTI164 in Rett syndrome registered on ClinicalTrials.gov
  4. metOpen-label Phase I/II study of NTI164 in 11 girls with Rett syndrome published: improvement on CGI-I (p=0.028), CGI-S, RSBQ total score and caregiver burden after 12 weeks; well tolerated.↗
  5. Open-label Phase I/II study of NTI164 in Rett syndrome (NCT06621043) started per ClinicalTrials.gov.

Readouts

  • October 2028AnticipatedRegistry resultsNCT07257978

    ClinicalTrials.gov estimated primary completion of the Phase II/III placebo-controlled crossover study of NTI164 in Rett syndrome: October 2028 (not yet recruiting; estimated start July 2027).

  • 2025-06-26ReportedFull resultsmetNCT06621043

    Open-label Phase I/II study of NTI164 in 11 girls with Rett syndrome published: improvement on CGI-I (p=0.028), CGI-S, RSBQ total score and caregiver burden after 12 weeks; well tolerated. ↗

Clinical trials in Rett syndrome

NCT07257978NTIRTT2Phase 2/3Activen=40

A Phase II/III Double-blind, Randomised, Placebo-controlled, Crossover Study Investigating the Efficacy and Safety of NTI164 in Children and Young Adults With Rett Syndrome

Started Jul 2027· Primary completion Oct 2028· 📍 1 site across 1 country (Australia)

NCT06621043NTIRTT1Phase 1/2Completedn=14

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

Started Sept 2023· Primary completion Dec 2025· 📍 1 site across 1 country (Australia)

Formulations

FormulationRouteRegimenPharmacokinetics
NTI164 oral oil (weight-based, twice daily)
Oil-based oral extract. Rett Phase I/II: started at 5 mg/kg and titrated up to 20 mg/kg per day by tolerance, given twice daily for 12 weeks. Harmony ASD Phase II/III: up to 20 mg/kg/day for 8 weeks. PANS Phase I/II: 20 mg/kg/day for 12 weeks. Healthy-volunteer PK study: 20 mg/kg.
OralTwice daily—

Mechanism of action (compound-wide)

No single molecular target is claimed. NTI164 is a multi-constituent cannabis extract led by cannabidiolic acid (CBDA) with minor cannabinoids and very low THC; the sponsor attributes its activity to modulation of neuroinflammatory signalling, immune dysregulation and epigenetic pathways. In vitro it attenuated inflammation-induced up-regulation of microglial inflammatory markers in BV-2 cells (CBD alone did not) and promoted neuron survival under excitotoxic conditions. In an open-label PANS study, multi-omic blood analyses showed treatment-associated modulation of epigenetic, ribosomal and immune pathways in leucocytes.

TargetActionAffinity

← Full NTI164 compound page (identity, identifiers, all indications)

Sources

  1. Keating BA, et al. Full-Spectrum Medicinal Cannabis Plant Extract 0.08% THC (NTI164) Improves Symptoms of Rett Syndrome: An Open-Label Study. J Paediatr Child Health. 2025 — Journal of Paediatrics and Child Health (Wiley) / PubMed
  2. NCT06621043 (NTIRTT1) - Phase I/II study of NTI164 in Rett syndrome — ClinicalTrials.gov (U.S. National Library of Medicine)
  3. NCT07257978 (NTIRTT2) - Phase II/III double-blind, randomised, placebo-controlled crossover study of NTI164 in Rett syndrome — ClinicalTrials.gov (U.S. National Library of Medicine)
  4. Quarterly Activities Report for the period ending 31 March 2026 (2026-04-29) — Neurotech International Limited (ASX announcement)