A Study to Investigate LP352 in Children and Adults With Developmental and Epileptic Encephalopathy (DEE)

Inclusion Criteria:

• The participant has satisfactorily completed Study LP352-301 or LP352-302 Visit 8,and who, in the opinion of the investigator, may benefit from continued LP352administration.

• Diagnosis of DEE that includes Dravet Syndrome (DS), Lennox-Gastaut Syndrome (LGS),or DEE Other (as defined and evaluated in Study LP352-301 or LP352-302).

• Has at least one reliable and consistent parent, legal guardian, or caregiver duringthe study.

• The participant or legal representative must be willing and able to provide writteninformed consent

• The participant, parent, or caregiver is willing and able (in the judgment of theinvestigator) to comply with completion of the diaries throughout the study.

Exclusion Criteria:

• The participant is receiving exclusionary medications.

• Current use of any cannabis product or cannabidiol that is not in oralsolution/capsule/tablet form, not obtained from a government-approved dispensary, orcontaining ≥50% Delta-9-tetrahydrocannabinol (THC).

• The participant has unstable, clinically significant neurologic (other than thedisease being studied, eg, recurrent strokes), psychiatric, cardiovascular (eg,pulmonary arterial hypertension, cardiac valvulopathy, orthostatichypotension/tachycardia) pulmonary, hepatic, renal, metabolic, gastrointestinal,urologic, immunologic, hematopoietic, or endocrine disease or other abnormalitywhich may impact the ability of the participant to participate or potentiallyconfound the study results.

• The participant is unable or unwilling to comply with any of the study requirementsor timelines.