Adjunctive GNX Treatment Compared With Placebo in Children and Adults With TSC-related Epilepsy

Inclusion Criteria

• Clinical or mutational diagnosis of TSC consistent with:
• Molecular confirmation of a pathogenic mutation in TSC1 or TSC2. A pathogenic mutation is defined as a mutation that clearly prevents protein synthesis and/or inactivates the function of the TSC1 or TSC2 proteins (eg, nonsense mutation or frameshift mutations, large genomic deletions) or is a missense mutation whose effect on protein function has been established by functional assessment. The Principal investigator (PI) or designee must review the results of the genetic analysis and confirm that the causal relationship to the epilepsy syndrome is likely. OR
• Clinical diagnosis of definite TSC which includes 2 major features or 1 major feature with ≥ 2 minor features.
• Male or female participants aged 1 through 65 years, inclusive. For Europe (EU), Middle East and North Africa (MENA), and Oceania (OC) Male or Female participants aged 2 through 65 years, inclusive.
• Participant/parent(s) or LAR(s) willing to give written informed consent/assent, after being properly informed of the nature and risks of the study and prior to engaging in any study related procedures. If the participant is not qualified nor able to provide written informed consent based on age, developmental stage, intellectual capacity, or other factors, parent(s)/LAR(s) must provide consent for study participation, if appropriate.
• Failure to control seizures despite appropriate trial of 2 or more Anti-seizure medication (ASMs) at therapeutic doses and for adequate duration of treatment per PI judgment.
• Participants should be on a stable regimen of ASMs (including moderate or strong inducer or inhibitor ASM eg, carbamazepine, phenytoin, etc.) at therapeutic doses for ≥ 28 days prior to the screening visit, and without a foreseeable change in dosing for the duration of the study. (Note: Minor dose adjustment to address tolerability and safety events may be allowed on case-by-case basis and it should be discussed with the study medical monitor.)
• A history of at least 8 countable seizures per month in the 2 months prior to screening with no more than 1 seizure free week in each month. This includes seizures of any kind.
• Have at least 8 primary endpoint seizures in the first 28 days following the screening visit.

The primary endpoint seizure types are defined as the following:

• focal motor seizures without impairment of consciousness or awareness
• focal seizures with impairment of consciousness or awareness with motor features
• focal seizures evolving to bilateral, tonic-clonic seizures
• generalized motor seizures including tonic-clonic, bilateral tonic, bilateral clonic, or atonic/drop seizures.

Seizures that do not count towards the primary endpoint include:

• Focal or generalized nonmotor seizures (eg, absence seizures or focal nonmotor seizures with or without impairment of awareness)
• Infantile or epileptic spasms
• Myoclonic seizures.
• Participants with surgically implanted vagal nerve stimulator (VNS) will be allowed to enter the study provided that all of the following conditions are met:
• The VNS has been in place for ≥ 6 months prior to the screening visit.
• The settings must have remained constant for 3 months prior to the screening visit and are expected to remain constant throughout the study.
• The battery is expected to last for the duration of the study.
• Parent(s)/caregiver(s)/LAR(s) or the participant, as appropriate, is (are) willing and able to maintain an accurate and complete daily seizure eDiary for the duration of the study.
• Willing and able to take IP (suspension) as directed with food (TID).
• Women of childbearing potential (WOCBP) must be using a medically acceptable method of birth control and have a negative quantitative serum beta-human chorionic growth hormone (β-HCG) test collected at the initial screening and Baseline visits.Childbearing potential is defined as a female who is biologically capable of bec