A Study to Evaluate Safety, Tolerability, and Pharmacokinetics of Fenfluramine (Hydrochloride) in Infants 1 Year to Less Than 2 Years of Age With Dravet Syndrome (ORCHID)

Open-Label, Single-Arm, Phase 3 Study to Evaluate Safety, Tolerability, and Pharmacokinetics of Fenfluramine (Hydrochloride) in Infants 1 Year to Less Than 2 Years of Age With Dravet Syndrome

The primary purpose of this study is evaluate the safety and tolerability of fenfluramine hydrochloride (HCl) 0.2 to 0.8 mg/kg/day in infants 1 year to less than 2 years of age with Dravet syndrome.

Study Overview

• Status: Active, not recruiting
• Conditions: Dravet Syndrome
• Intervention / Treatment: Drug: fenfluramine

• Study Type: Interventional
• Enrollment (Actual): 25
• Phase: Phase 3

Contacts and Locations

Study Locations

• Belgium
  • Brussels, Belgium
    • Ep0213 502
  • Edegem, Belgium
    • Ep0213 501
• Germany
  • Bielefeld, Germany
    • Ep0213 303
• Italy
  • Florence, Italy
    • Ep0213 202
  • Genova, Italy
    • Ep0213 203
  • Roma, Italy
    • Ep0213 201
  • Roma, Italy
    • Ep0213 204
• United Kingdom
  • Glasgow, United Kingdom
    • Ep0213 403
  • London, United Kingdom
    • Ep0213 401
• United States
  • Tennessee
    • Memphis, Tennessee, United States, 38103-2800
      • Ep0213 105
  • Texas
    • Dallas, Texas, United States, 75207
      • Ep0213 107
  • Washington
    • Seattle, Washington, United States, 98105
      • Ep0213 103

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Participant is ≥1 to <2 years of age as of the day of the first administration of study drug
• Participant has a documented diagnosis or likely diagnosis of Dravet syndrome according to the International League Against Epilepsy (ILAE) criteria and as agreed by the Epilepsy Study Consortium (ESC)
• Participant must be currently receiving ≥1 concomitant anti seizure medication (ASM) at a stable dose for ≥4 weeks prior to the Screening Visit and is expected to remain stable throughout the study. Rescue medications for seizures are not counted towards the total number of ASMs
• Participant must have drug resistant epilepsy as defined as a history of failure of adequate trials of 2 tolerated, appropriately chosen and used antiepileptic drug schedules (whether as monotherapies or in combination) to achieve sustained seizure freedom
• Participants must have ≥1 countable motor seizures (CMS) during the Baseline Period. The CMS include distinct seizures of generalized tonic-clonic, bilateral clonic, focal motor, bilateral tonic, atonic (drop), bilateral tonic/atonic, or focal to bilateral tonic-clonic type. If the participant fails to have ≥1 qualifying seizures in 28 days, the Baseline Period may be extended by an additional 14 days with Sponsor approval. Participants with an extended Baseline Period must still have ≥1 CMS in the 28 days immediately prior to the day of the first administration of study drug
• Body weight is ≥8 kg
• Males and females

Exclusion Criteria:

• Participant has a known hypersensitivity to fenfluramine hydrochloride (HCl) or any of the excipients in the study drug
• Participant has an exclusionary cardiovascular or cardiopulmonary abnormality based on echocardiogram (ECHO), electrocardiogram (ECG), or physical examination and is not approved for entry by the central cardiac reader
• Participant has a diagnosis of pulmonary arterial hypertension
• Participant has a clinically significant medical condition, including chronic obstructive pulmonary disease, interstitial lung disease, or portal hypertension, or has had clinically relevant symptoms or a clinically significant illness currently or in the 4 weeks prior to the Screening Visit, other than epilepsy, that in the opinion of the Investigator would negatively impact study participation, collection of study data, or pose a risk to the participant
• Participant has current or past history of cardiovascular or cerebrovascular disease, such as cardiac valvulopathy, myocardial infarction or stroke, severe ventricular arrhythmias, or clinically significant structural cardiac abnormality, including but not limited to mitral valve prolapse, atrial or ventricular septal defects, patent ductus arteriosus, and patent foramen ovale with reversal of shunt. (Note: Patent foramen ovale or a bicuspid aortic valve are not considered exclusionary.)
• Participant has a current or past history of glaucoma
• Participant has moderate to severe hepatic impairment, assessed based on the Child-Pugh classification system
• Participant has moderate to severe renal impairment (estimated glomerular filtration rate <50 mL/min/1.73 m^2 calculated with the updated Bedside Schwartz equation for children
• QT interval corrected (QTc) >450 msec
• Participant is taking >4 concomitant ASMs
• Participant is receiving concomitant treatment with cannabidiol other than Epidiolex/Epidyolex or is being actively treated with tetrahydrocannabinol (THC) or any marijuana product for any condition
• Participant is receiving concomitant therapy with any of the following: centrally-acting anorectic agents; monoamine-oxidase inhibitors; any centrally-acting compound with clinically appreciable amount of serotonin agonist or antagonist properties, including serotonin reuptake inhibition; other centrally-acting noradrenergic agonists, including atomoxetine; or cyproheptadine. Disallowed medications are subject to washout of ≥5 half-lives before the first day of study drug administration
• Participant is currently receiving another investigational product(s) or has received another investigational product within 30 days or within <5 times the half-life of that investigational product, whichever is longer, prior to the Screening Visit
• Participant has previously been treated with Fintepla (fenfluramine HCl) prior to the Screening Visit

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: Fenfluramine Open-label; All study participants will initiate fenfluramine hydrochloride (HCl) treatment at 0.2 mg/kg/day in the Dose-Finding Period and may be up-titrated to a maximum of 0.8 mg/kg/day based on the Investigators discretion. The dose of fenfluramine HCl can be flexibly titrated during the Maintenance Period. Study participants, who discontinue early will participate in the Taper Period. All participants will complete an End of Treatment (EOT) Visit.

Drug: fenfluramine; The study drug, fenfluramine HCl, is an oral solution to be administered in equal doses twice daily (BID). It will be based on the current dose and participant's weight (kg).; Other Names: Fintepla

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change from Baseline in QT interval corrected by Fridericia (QTcF) at Visit 13 (End of Treatment/Early Termination (EOT/ET))	QTcF is the QT interval corrected for heart rate according to Fridericia's formula. Higher values correspond to prolongation of QT interval.	Week 52 (Visit 13; EOT/ET), compared to Baseline
Occurrence of a treatment-emergent (ie, post-Baseline through Visit 13 [EOT/ET]) result which meets the FDA case definition of drug associated valvulopathy	Drug associated valvulopathy refers to aortic regurgitation with severity mild or greater and/or mitral regurgitation with severity moderate or greater.	From post-Baseline (Day 1) through Visit 13 (EOT/ET) (up to 52 weeks)
Occurrence of treatment-emergent (ie, post-Baseline through Visit 13 [EOT/ET]) clinically confirmed valvular heart disease (VHD)	Clinically confirmed VHD is an aortic regurgitation with mild or greater severity and/or a mitral regurgitation with moderate or greater severity.	From post-Baseline (Day 1) through Visit 13 (EOT/ET) (up to 52 weeks)
Change from Baseline in body weight (Z-score) at each visit	Body weight (Z-score) refers to the number of standard deviations a participant's body weight lies from the mean, when compared to others of similar gender and age.	Week 1 (Visit 3), Week 4 (Visit 5), Week 8 (Visit 7), Week 12 (Visit 8), Week 16 (Visit 9), Week 20 (Visit 10), Week 26 (Visit 11), Week 39 (Visit 12), Week 52 (Visit 13), Postdose Safety Follow-Up (Visit 14), compared to Baseline
Change from Baseline in recumbent length (Z-score) at each visit	Recumbent length (Z-score) refers to the number of standard deviations a participant's body weight lies from the mean, when compared to others of similar gender and age.	Week 1 (Visit 3), Week 4 (Visit 5), Week 8 (Visit 7), Week 12 (Visit 8), Week 16 (Visit 9), Week 20 (Visit 10), Week 26 (Visit 11), Week 39 (Visit 12), Week 52 (Visit 13), Postdose Safety Follow-Up (Visit 14), compared to Baseline
Occurrence of a clinically significant abnormality on the neurological examination at each visit	A complete neurological examination will be conducted by the investigator for each participant covering cranial nerves, muscle strength and tone, reflexes, coordination, sensory function, and gait.	Week 1 (Visit 3), Week 4 (Visit 5), Week 8 (Visit 7), Week 12 (Visit 8), Week 16 (Visit 9), Week 20 (Visit 10), Week 26 (Visit 11), Week 39 (Visit 12), Week 52 (Visit 13), Postdose Safety Follow-Up (Visit 14), compared to Baseline

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Percentage change from the Baseline Period (ie, Baseline) in monthly (28 days) countable motor seizure frequency (CMSF), during Weeks 9 through 20	The percentage change from the Baseline Period (Baseline) in "monthly (28 days) countable motor seizure frequency," or CMSF, during Weeks 9 through 20	During Weeks 9 to 20, compared to Baseline
Percentage change from Baseline in CMSF during Weeks 1 through 20	The percentage change from the Baseline Period (Baseline) in "monthly (28 days) countable motor seizure frequency," or CMSF, during Weeks 1 through 20	During Weeks 1 to 20, compared to Baseline
Percentage change from Baseline in CMSF during the Treatment Period (Week 1 through the EOT/ET Visit)	The percentage change from the Baseline Period (Baseline) in "monthly (28 days) countable motor seizure frequency," or CMSF, during the Treatment Period (Week 1 through the EOT/ET Visit; up to 52 weeks)	During the Treatment Period (Week 1 through EOT/ET) (up to 52 weeks), compared to Baseline
Achievement of a Clinical Global Impression - Improvement (CGI-I) rating of "much improved" or "very much improved" as assessed by the Principal Investigator at Week 20	The CGI-I rating scale permits a global evaluation of the participant's improvement over time by the investigator on a 7-point scale.	At Week 20
Achievement of a CGI-I rating of "much improved" or "very much improved" as assessed by the parent/caregiver at Week 20	The CGI-I rating scale permits a global evaluation of the participant's improvement over time by the parent/caregiver on a 7-point scale.	At Week 20
Steady-state maximum plasma concentration (Cmax) of fenfluramine and norfenfluramine at Week 12	Mean peak (maximum) plasma concentration of fenfluramine and norfenfluramine will be reported at Study Week 12 when participants are in the Maintenance Period.	At Week 12
Steady-state minimum plasma concentration (Cmin) of fenfluramine and norfenfluramine at Week 12	Mean minimum plasma concentration of fenfluramine and norfenfluramine will be reported at Study Week 12 when participants are in the Maintenance Period.	At Week 12
Area under the plasma concentration time curve from time zero to 24 hours (AUC0 24) for steady-state fenfluramine and norfenfluramine at Week 12	Mean AUC0-24 values of fenfluramine and norfenfluramine will be reported at Study Week 12 when participants are in the Maintenance Period.	At Week 12

Collaborators and Investigators

• Sponsor: UCB BIOSCIENCES, Inc.
• Investigators: Study Director: UCB Cares, 001 844 599 2273

Study record dates

Study Major Dates

• Study Start (Actual): May 21, 2024
• Primary Completion (Estimated): September 3, 2026
• Study Completion (Estimated): December 16, 2026

Study Registration Dates

• First Submitted: October 23, 2023
• First Submitted That Met QC Criteria: November 2, 2023
• First Posted (Actual): November 7, 2023

Study Record Updates

• Last Update Posted (Actual): April 3, 2026
• Last Update Submitted That Met QC Criteria: April 2, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: pediatrics; Dravet syndrome; fenfluramine; Fintepla
• Additional Relevant MeSH Terms: Epileptic Syndromes; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Epilepsy, Generalized; Epilepsy; Epilepsies, Myoclonic; Organic Chemicals; Amines; Phenethylamines; Ethylamines; Fenfluramine
• Other Study ID Numbers: EP0213; U1111-1289-2867 (Other Identifier: World Health Organization (WHO)); 2022-502359-75 (Registry Identifier: EU Clinical Trials)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Data from this study 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 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. This plan may change if a determination is made that the data cannot be adequately anonymized.
• IPD Sharing Time Frame: Data from this study 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.
• IPD Sharing Access Criteria: 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.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; CSR

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No