General Information

Diacomit (stiripentol) has an unknown mechanism of action but is thought to work through the GABAA receptor. 

Diacomit is specifically indicated for the treatment of seizures associated with Dravet syndrome (DS) in patients 2 years of age and older taking clobazam.

Diacomit is supplied both as an oral capsule and as a powder for oral suspension. The recommended oral dosage of Diacomit is 50 mg/kg/day, administered in 2 or 3 divided doses (i.e., 16.67 mg/kg three times daily or 25 mg/kg twice daily). If the exact dosage is not achievable given the available strengths, round to the nearest possible dosage, which is usually within 50 mg to 150 mg of the recommended 50 mg/kg/day. A combination of the two Diacomit strengths can be used to achieve this dosage. The maximum recommended total dosage is 3,000 mg/day. Gradual Withdrawal: If Diacomit treatment is discontinued, the drug should be withdrawn gradually to minimize the risk of increased seizure frequency and status epilepticus.

Mechanism of Action

The mechanism by which Diacomit exerts its anticonvulsant effect in humans is unknown. Possible mechanisms of action of its anticonvulsant effect in humans include direct effects mediated through the GABAA receptor and indirect effects involving inhibition of cytochrome P450 activity with resulting increase in blood levels of clobazam and its active metabolite.

Side Effects

Adverse effects associated with the use of Diacomit may include, but are not limited to, the following:

• somnolence
• decreased appetite
• agitation
• ataxia
• weight decreased
• hypotonia
• nausea
• tremor
• dysarthria
• insomnia

Clinical Trial Results

The FDA approval of Diacomit was based on two multicenter placebo-controlled trials, STICLO France and STICLO Italy, which enrolled a combined total of 64 subjects. The primary efficacy endpoint in both trials was the responder rate, with a responder defined as a patient who experienced a greater than 50% decrease in the frequency (per 30 days) of generalized clonic or tonic-clonic seizures during the double-blind treatment period compared to the 4-week baseline period. In STICLO France, the responder rate for patients receivingDiacomit was 71%, compared to 5% for patients receiving placebo. In STICLO Italy, the responder rate for patients receiving Diacomit was 67%, compared to 9.1% for patients receiving placebo.