New Analysis Published in Multiple Sclerosis Journal Assesses Long-Term Use of UPLIZNA (inebilizumab-cdon) for the Treatment of Neuromyelitis Optica Spectrum Disorder (NMOSD)

Horizon Therapeutics plc (Nasdaq: HZNP) today announced the publication of a post-hoc analysis from the N-MOmentum phase 2/3 pivotal trial of UPLIZNA, which highlights a sustained effect on attack risk with no new safety signals in people with NMOSD who received the treatment for four or more years. These data are published in the Multiple Sclerosis Journal.

NMOSD is a rare, severe autoimmune disease that attacks the optic nerve, spinal cord and brain stem. The attacks are often recurrent and can cause irreversible damage to the nerves, leading to cumulative visual and motor disabilities over time. UPLIZNA is the first and only FDA-approved anti-CD19 B-cell-depleting humanized monoclonal antibody for the treatment of adult patients with anti-aquaporin-4 (AQP4) antibody positive NMOSD.

“This long-term study is important because NMOSD is a chronic disease that requires lifelong management. Physicians need to understand the implications of prolonged treatment,” said Bruce Cree, M.D., Ph.D., MAS, professor of clinical neurology at the University of California San Francisco Weill Institute for Neurosciences and primary study investigator. “It is highly encouraging to see that most patients in this study were attack-free after the first year of UPLIZNA treatment and that new safety concerns were not observed. The data demonstrate that long-term UPLIZNA use is associated with a reduced risk of NMOSD attacks – possibly due to the depth and extent of B-cell depletion with repeated doses.”

The post-hoc analysis represents the experience of 75 people with AQP4 antibody positive NMOSD who were treated with UPLIZNA for four or more years during the open-label extension period of the N-MOmentum trial.

Key study findings include the following:

• A total of 18 attacks occurred in 13 people, with an annualized attack rate of 0.052 attacks per person year.
• The small number of total attacks decreased significantly after the first year of treatment with UPLIZNA.
  • 67% of attacks occurred within the first year (12 attacks).
  • 92% of patients were attack-free in subsequent years (two attacks each during years two to four).
• The infection rate did not increase over time on treatment with UPLIZNA.
• UPLIZNA was generally well tolerated, with few treatment-related dose interruptions and no treatment discontinuations.

“NMOSD is a complex and often unpredictable B-cell-mediated disease that presents significant challenges to both patients and physicians,” said Kristina Patterson, M.D., Ph.D., medical director, neuroimmunology, Horizon. “With recent treatment advancements, the NMOSD community now has more options than ever before – including UPLIZNA, which is engineered for broad, deep and durable B-cell depletion. We are fully committed to increasing our understanding of this disease so we can continue to improve patient care.”