Sodium Oxybate in Patients With Alternating Hemiplegia of Childhood (AHC-SO)

Inclusion Criteria

• •AHC classic criteria:
• •* Onset of symptomatology prior to 18 months of age
• •* Repeated attacks of hemiplegia involving either side of the body
• •* Paroxysmal disturbances, including tonic or dystonic spells, oculomotor abnormalities, and various autonomic phenomena, during hemiplegic bouts or in isolation
• •* Episodes of bilateral hemiplegia or quadriplegia starting either as generalization of a hemiplegic episode or bilateral from the beginning
• •* Immediate disappearance of symptoms upon sleeping, with possible resumption 10-20 minutes after waking
• •* Evidence of developmental delay and neurologic abnormalities including choreoathetosis, dystonia, or ataxia
• •In addition:
• •Provision of a complete daily event log for 6 weeks prior to initiation of sodium oxybate therapy, including the: (1) frequency, (2) duration, (3) type, (4) severity of episodes, and (5) therapies, if any, used in an attempt to abort the episode
• •Ages 6 months to 25 years at the time of study enrollment
• •Minimum of 3 AHC episodes weekly, lasting at least 10 minutes each, on average prior to study enrollment
• •Brain neuroimaging studies excluding alternative etiology for symptoms
• •Documented absence of epileptiform features on EEG during typical ictal events
• •Ability of primary caregivers of study participants to submit online daily AHC Episode Logs indicating frequency and duration of ictal episodes over the entire study period
• •Written informed consent from parents/guardians and assent from children 7 years or older
• •Girls/women \> 12 years of age will be required to be on birth control continuously if they are considered at risk to become pregnant. Those not on birth control will be required to have a screening pregnancy test at baseline, and to confirm their willingness to practice birth control or abstain from sexual activity for the duration of treatment with study medication.