A phase 3 double-blind, randomised non-inferiority study compared once-daily zonisamide to twice-daily prolonged-release carbamazepine as monotherapy in 583 adults with newly diagnosed partial seizures, with or without secondary generalised tonic-clonic seizures. Treatment was given for up to 24 months.
Non-inferior to carbamazepine
Results showed that 79.4% of patients receiving zonisamide in the per-protocol population remained free of seizures for six months, compared with 83.7% in the carbamazepine group (adjusted absolute treatment difference, –4.5%, 95% CI –12.2% to 3.1%), meeting the criteria for non-inferiority.
Similar safety profile
Similar incidences of treatment-emergent adverse events, including serious events and events leading to withdrawal, were observed in the two arms.