n January 27, 2026, Neurocrine Biosciences announced the commencement of a Phase II clinical trial for NBI-1065890. This investigational compound is a selective vesicular monoamine transporter 2 (VMAT2) inhibitor being developed specifically for the treatment of tardive dyskinesia (TD) in adults.
Tardive dyskinesia is a movement disorder characterized by involuntary, repetitive body movements, often resulting from long-term use of antipsychotic medications.
Key trial components and objectives:
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Study Design: A randomized, double-blind, placebo-controlled Phase II trial enrolling approximately 100 adult participants.
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Primary Endpoint: The study aims to measure the change from baseline in the Abnormal Involuntary Movement Scale (AIMS) total score after eight weeks of treatment.
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Product Profile: Administered orally, NBI-1065890 features distinct physicochemical properties. The company believes these unique attributes could potentially benefit a broader and more diverse range of patients affected by TD.
This milestone reinforces Neurocrine’s commitment to VMAT2 biology, building on its history as the developer of Valbenazine—the first FDA-approved treatment for TD in 2017. While the company recently reported that a Phase III trial for Valbenazine in dyskinetic cerebral palsy did not meet its endpoints in late 2025, the advancement of NBI-1065890 represents a strategic effort to redefine therapeutic options for patients with hyperkinetic movement disorders and disrupted dopaminergic signaling.