Neurocrine Biosciences (NASDAQ:NBIX) announced on January 26, 2026, the initiation of its Phase 2 clinical study for NBI-1065890, an investigational compound targeting tardive dyskinesia (TD).
The study marks a strategic push to evolve the company's leadership in the VMAT2 (vesicular monoamine transporter 2) space, where it already holds a dominant market share with its blockbuster drug, Ingrezza (valbenazine).
NBI-1065890 is described as a highly selective VMAT2 inhibitor with distinct chemical and physical properties.
While existing treatments like Ingrezza have revolutionized the field, Neurocrine's goal with this new candidate is to offer a "potentially differentiated profile," including the possibility of longer-acting dosing options.
By inhibiting VMAT2, these drugs reduce the amount of dopamine that is packaged into vesicles and released into the synaptic cleft.
In conditions like tardive dyskinesia—which is caused by long-term use of dopamine-blocking antipsychotics—this reduction in synaptic dopamine helps calm the uncontrollable, repetitive muscle movements characteristic of the disorder.
The newly initiated study is a randomized, double-blind, placebo-controlled trial expected to enroll approximately 100 adults with TD.
Neurocrine’s legacy in VMAT2 biology is well-established; the company received the first-ever FDA approval for a TD treatment (valbenazine) in 2017, followed by an approval for Huntington’s chorea in 2023.
With Ingrezza generating billions in annual revenue, NBI-1065890 represents the company’s "life-cycle management" strategy to ensure it remains at the forefront of the movement disorder market as patents for first-generation therapies eventually expire.
The company expects to report further insights into its clinical pipeline during its upcoming earnings call on February 11, 2026.