A Study to Investigate the Long-Term Safety of ZX008 (Fenfluramine Hydrochloride) Oral Solution in Children and Adults With Epileptic Encephalopathy Including Dravet Syndrome and Lennox-Gastaut Syndrome

A Study to Investigate the Long-Term Safety of ZX008 (Fenfluramine Hydrochloride) Oral Solution in Children and Adults With Epileptic Encephalopathy Including Dravet Syndrome and Lennox-Gastaut Syndrome

An Open-Label Extension Trial to Assess the Long-Term Safety of ZX008 (Fenfluramine Hydrochloride) Oral Solution as an Adjunctive Therapy for Seizures in Patients With Rare Seizure Disorders Such as Epileptic Encephalopathies Including Dravet Syndrome and Lennox-Gastaut Syndrome

This is an international, multicenter, open-label, long-term safety study of ZX008 in subjects with Dravet syndrome, Lennox-Gastaut syndrome or epileptic encephalopathy

This is an international, multicenter, open-label, long-term safety study of ZX008 in patients with epileptic encephalopathy, including Dravet syndrome or Lennox-Gastaut syndrome. Subjects eligible for participation are those with Dravet syndrome who are currently enrolled in Study ZX008-1503, or those with Lennox-Gastaut syndrome who have successfully completed Study ZX008-1601-Part 2, and are candidates for continued treatment with ZX008 for an extended period of time, or those with Dravet syndrome, Lennox-Gastaut syndrome, or another epileptic encephalopathy who have completed participation in another Zogenix-sponsored study and have been invited to participate in this study.

ZX008 is supplied as an open-label oral solution.Doses will include up to 0.8 mg/kg/day divided into 2 daily doses, up to a maximum of 30 mg/day (subjects taking concomitant STP will receive up to 0.5 mg/kg/day, up to a maximum of 20 mg/day) in a concentration of 2.5 mg/mL.

Change in Adverse Events and Serious Adverse Events leading to study withdrawal in subjects receiving open label ZX008

The analysis will include abnormal hematology and chemistry laboratory results outside of reference ranges

The rating by parent/caregiver of the patient's change in cognitive symptoms since the beginning of study as "very much improved", "much improved", "minimally improved", "no change", "minimally worse", "much worse", or "very much worse".

The rating by parent/caregiver of the patient's change in behavioral symptoms since the beginning of study as "very much improved", "much improved", "minimally improved", "no change", "minimally worse", "much worse", or "very much worse".

The rating by parent/caregiver of the patient's change in motor symptoms since the beginning of study as "very much improved", "much improved", "minimally improved", "no change", "minimally worse", "much worse", or "very much worse".

The rating by investigator of the patient's change in cognitive symptoms since the beginning of study as "very much improved", "much improved", "minimally improved", "no change", "minimally worse", "much worse", or "very much worse".

The rating by investigator of the patient's change in behavioral symptoms since the beginning of study as "very much improved", "much improved", "minimally improved", "no change", "minimally worse", "much worse", or "very much worse".

The rating by investigator of the patient's change in motor symptoms since the beginning of study as "very much improved", "much improved", "minimally improved", "no change", "minimally worse", "much worse", or "very much worse".

The rating by parent/caregiver of the patient's overall change in symptoms since the beginning of study as "very much improved", "much improved", "minimally improved", "no change", "minimally worse", "much worse", or "very much worse"

The rating by investigator of the patient's overall change in symptoms since the beginning of study as "very much improved", "much improved", "minimally improved", "no change", "minimally worse", "much worse", or "very much worse"

Inclusion Criteria: Male or nonpregnant, nonlactating female Satisfactory completion of a core study Has a rare seizure disorder, such as epileptic encephalopathy and has successfully completed another Zogenix-sponsored clinical trials with ZX008 Subject's caregiver is willing and able to be compliant with study procedures, visit schedule and study drug accountability Exclusion Criteria: Current cardiac valvulopathy or pulmonary hypertension that is clinically significant Moderate or severe hepatic impairment Receiving monoamine oxidase inhibitors, serotonin agonists, serotonin antagonists, and serotonin reuptake inhibitors within 14 days of receiving ZX008

Data from this trial may be requested by qualified researchers six months after product approval in the US and/or Europe, or global development is discontinued, and 18 months after trial completion. Investigators may request access to anonymized individual patient-level data and redacted trial documents which may include: analysis-ready datasets, study protocol, annotated case report form, statistical analysis plan, dataset specifications, and clinical study report. Prior to use of the data, proposals need to be approved by an independent review panel at www.Vivli.org and a signed data sharing agreement will need to be executed. All documents are available in English only, for a pre-specified time, typically 12 months, on a password protected portal. This plan may change if the risk of re-identifying trial participants is determined to be too high after the trial is completed; in this case and to protect participants, individual patient-level data would not be made available.

Data from this trial may be requested by qualified researchers six months after product approval in the US and/or Europe or global development is discontinued, and 18 months after trial completion.

Qualified researchers may request access to anonymized IPD and redacted study documents which may include: raw datasets, analysis-ready datasets, study protocol, blank case report form, annotated case report form, statistical analysis plan, dataset specifications, and clinical study report. Prior to use of the data, proposals need to be approved by an independent review panel at www.Vivli.org and a signed data sharing agreement will need to be executed. All documents are available in English only, for a pre-specified time, typically 12 months, on a password protected portal.