Ingrezza Shows 48-Week Remission

This analysis was presented at the 2025 Psychiatry Update Conference in Chicago.

"These findings further establish Ingrezza as a highly effective long-term treatment option for individuals living with tardive dyskinesia, regardless of their underlying psychiatric condition, including schizophrenia, schizoaffective disorder or mood disorder," said Eiry W. Roberts, M.D., Chief Medical Officer, Neurocrine Biosciences. "The significant improvements observed in AIMS score and the high remission rates highlight the efficacy of Ingrezza, at even the lowest dose."

The post-hoc analysis was conducted using data from 103 participants who reached the final Week 48 visit in the KINECT 4 clinical trial and assessed a proposed threshold for remission of tardive dyskinesia (TD) symptoms using the Abnormal Involuntary Movement Scale (AIMS). The threshold for remission was defined as an AIMS item score of ≤1 (rating of "none" or "minimal") in each of the seven body regions (items 1-7). The percentage who met the threshold for remission was analyzed by dose (40 mg and 80 mg) and by psychiatric diagnosis (schizophrenia or schizoaffective disorder, mood disorder).

A majority of participants who received 48 weeks of once-daily Ingrezza reached the threshold for remission of TD while on treatment, regardless of underlying psychiatric diagnosis or dose: i) 59.2% (61/103) of participants who completed the study achieved remission, including 58.6% (17/29) of participants on the 40 mg dose and 59.5% (44/74) of participants on the 80 mg dose. Both 40 mg and 80 mg doses of Ingrezza showed significant improvements in AIMS total scores, with mean baseline scores of 12.4 (40 mg) and 15.1 (80 mg) decreasing to 2.1 and 2.5, respectively, at Week 48. ii) Remission rates were consistent across psychiatric diagnoses, with 57.7% (41/71) of participants with schizophrenia or schizoaffective disorder and 62.5% (20/32) of participants with mood disorders achieving remission. iii) Substantial Long-Term Improvements in Tardive Dyskinesia With Valbenazine 40 mg (from additional poster presentation at the 2025 Psychiatry Update Conference).

KINECT 4 is a Phase III, open-label study, in which 163 participants with moderate to severe TD and underlying schizophrenia, schizoaffective disorder or mood disorder (including bipolar disorder or major depressive disorder) received 48 weeks of open-label treatment with once-daily Ingrezza (40 mg or 80 mg capsules) followed by a four-week washout. Dosing was initiated at 40 mg/day in all participants, with escalation to 80 mg/day at Week 4 based on effectiveness and tolerability. Dose reduction to 40 mg was allowed in participants who could not tolerate the 80 mg dose. Participants were discontinued if the new dose was not tolerated.

Participants experienced TD improvements during long-term treatment as demonstrated by mean change from baseline to Week 48 in AIMS total score (sum of items 1-7, evaluated by site raters) with Ingrezza 40 mg/day (-10.2) or 80 mg/day (-11.0). Consistent with previous studies, Ingrezza was generally well tolerated. After Week 4, treatment emergent adverse events (TEAEs) that occurred in ≥ 5% of all participants (combined dose groups) were urinary tract infection (8.5%) and headache (5.2%). Changes from baseline in psychiatric stability, vital signs, electrocardiogram parameters and laboratory test values were generally small and not clinically significant.