April 30 (Reuters) - The U.S. Food and Drug

Administration (FDA) has approved the granule formulation of

Neurocrine Biosciences' ( NBIX ) Ingrezza drug to treat movement

disorders associated with Huntington's disease (HD), the company

said on Tuesday.

Huntington's disease is an inherited condition that causes

the progressive breakdown of nerve cells in the brain, resulting

in a gradual decline in motor control, cognition and mental

stability.

Ingrezza was first approved in 2017 in its oral capsule

formulation to treat adults with movement disorders tardive

dyskinesia and chorea.

The granule formulation, Ingrezza Sprinkle, was developed as

an alternative for patients with tardive dyskinesia and chorea

who face difficulty swallowing capsules.

The company did not immediately respond to a Reuters request

seeking details on the drug's availability and pricing.

Tardive dyskinesia is a medication-induced movement disorder

characterized by uncontrollable movements of the face, torso

and/or other body parts.

Chorea associated with HD is a movement disorder that can

interfere with swallowing and speech, among other bodily

functions.

The approval was based on positive data demonstrating the

equivalence and tolerability of Ingrezza granules compared with

the currently approved capsule version.

Ingrezza oral granules, available under three dosages - 40

mg, 60 mg and 80 mg - are to be sprinkled on soft foods prior to

administration.

TD Cowen analyst Phil Nadeau said Ingrezza could achieve

$3.2 bln in U.S. sales in tardive dyskinesia by 2028.

Nadeau estimates that the drug has only been adopted by

about 30,000 patients, indicating significant growth potential

for Ingrezza.

Israel-based Teva Pharmaceutical Industries'

Austedo is also approved to treat chorea stemming from

Huntington's disease.

Ingrezza recorded global sales of $1.84 billion in 2023 and

the company expects the drug to generate overall sales in the

range of $2.1 billion to $2.2 billion this year.