June 5 (Reuters) - Amgen ( AMGN ) said on Wednesday its

drug to treat patients with an immune system-related condition

has met the main goal of a late-stage study.

The company said its drug, Uplizna, showed a statistically

significant reduction in the risk of flares related to the rare

disease, compared to placebo.

The drug was being studied for the treatment of

Immunoglobulin G4-related disease, which is characterized by

periods of remission and unpredictable disease flares.

Amgen ( AMGN ) is planning to file for an approval in the United

States, based on the results.

Amgen ( AMGN ) had gained access to Uplizna through its $27.8 billion

deal with Horizon Therapeutics.

Uplizna is currently approved for Neuromyelitis Optica

Spectrum Disorder, also a type of rare disease, which affects

the brain and spinal cord.