Results:
SECONDARY, ADVERSE EVENT
Respective adjusted mean changes in MDS-UPDRS Part III total score at 16 and 24 weeks (primary endpoint) were –6.3 and –4.4 in the zonisamide add-on and –0.8 and 2.0 in the levodopa increase groups. The adjusted mean difference at 24 weeks was –6.4 (95% confidence interval [CI] –13.5, 0.7); the upper limit of the 95% CI (0.7) was lower than the non-inferiority margin (3.0). No significant between-group differences were observed in total scores of the MDS-UPDRS Part II, Eating Questionnaire, EuroQol-5 dimension-5 level, Zarit Caregiver Burden Interview, or other secondary endpoints. No notable between-group differences were observed in adverse event incidences.