A Study to Evaluate the Safety and Efficacy of JZP926 Capsule for the Treatment of Juvenile Myoclonic Epilepsy

This Phase 2/3 multicenter, randomized, placebo-controlled, double-blind study will evaluate the safety and efficacy of JZP926 capsule in participants aged ≥ 10 years with Juvenile Myoclonic Epilepsy (JME). The study will assess the efficacy of JZP926 capsule as an adjunctive treatment in reducing the frequency of myoclonic seizure days when compared with placebo, as well as the effect of JZP926 capsule on non-seizure endpoints.

• JZP926 capsule (Drug): Oral administration BID according to body weight
• Placebo (Drug): Oral administration BID according to body weight

Primary outcomes

• Change from baseline in myoclonic seizure days per 28 days (Part A and Part B) [Baseline up to end of 16 weeks treatment period]

Secondary outcomes

• Patient and Caregiver Global Impression of Change in Usual Daily Activities (P/CaGI-C UDA) (Part A and Part B) [Week 16]
• Proportion of participants who achieve ≥ 50% and ≥ 75% reduction from baseline in myoclonic seizure days (Part A and Part B) [Baseline up to end of 16 weeks treatment period]
• Change from baseline in days with any seizure type per 28 days (Part A and Part B) [Baseline up to end of 16 weeks treatment period]
• Number of days with fewer myoclonic seizures than participant average prior to entering the study per 28 days (Part A and Part B) [Baseline up to end of 16 weeks treatment period]
• Percent change from baseline (historical + prospective) in generalized tonic-clonic (GTC) seizure frequency (Part A and Part B) [Baseline up to end of 16 weeks treatment period]
• Number of participants reporting treatment-emergent adverse events (Part A and Part B) [Baseline up to end of 16 weeks treatment period]
• Mean plasma concentration for CBD [Baseline up to end of 16 weeks treatment period]
• Mean plasma concentration of metabolite 7-OH-CBD [Baseline up to end of 16 weeks treatment period]
• Mean plasma concentration of metabolite 7-COOH-CBD [Baseline up to end of 16 weeks treatment period]

Sex: All, ages: 10 Years to any

Inclusion Criteria

Participants are eligible to be included in the study only if all of the following criteria apply:

1. Is ≥ 10 years of age at the time of screening.
2. Has a diagnosis of JME per ILAE criteria as specified in the protocol.
3. Has at least 4 myoclonic seizure days per 28 days historical seizure frequency.

Exclusion Criteria

Participants are excluded from the study if any of the following criteria apply:

1. Presence of seizure types other than GTC, myoclonic, and absence seizures.
2. If historical MRI has been performed, participant's MRI reveals a cause of epilepsy other than JME.
3. Has a concurrent, confirmed diagnosis of non-epileptic seizures or events that can confound the assessment of the efficacy measures, in the opinion of the investigator.
4. The etiology of the participant's seizures is a progressive neurologic disease.
5. Has clinically unstable or progressive epilepsy.
6. Has clinically significant unstable medical condition(s), other than epilepsy, including unstable psychiatric disorders.
7. Has a history of status epilepticus in the 3 months prior to screening.
8. History of suicidal behavior, current suicidal risk as determined from history, or presence of active suicidal ideation as indicated by a positive response to Item 4 or Item 5 on the C-SSRS or is considered at risk of suicide or self-harm based on the clinical judgement of the investigator following interview with the participant and/or caregiver.
9. Has known or suspected hypersensitivity to cannabinoids or any of the excipients of the study intervention.
10. Is currently treated with Epidiolex or recently received treatment with Epidiolex within 28 days prior to screening.
11. Has a body weight < 20 kg or > 150 kg.
12. Is currently using or has used recreational or medicinal cannabis, cannabinoid/CBD based medications, products, or supplements (botanical or synthetic) within 28 days prior to screening.
13. Is unwilling or unable to abstain from recreational or medicinal cannabis, cannabinoid/CBD based medications, products, or supplements (botanical or synthetic) for the duration of the study.