New Long-Term Data for UPLIZNA (inebilizumab-cdon) in People Living with Neuromyelitis Optica Spectrum Disorder (NMOSD)

Horizon Therapeutics plc (Nasdaq: HZNP) today announced new UPLIZNA (inebilizumab-cdon) data being presented at the American Academy of Neurology’s 73rd Annual Meeting being held virtually April 17-22, 2021 (AAN 2021), including new, end-of-study data from the open-label extension period of the pivotal N-MOmentum trial in patients with NMOSD. 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.

“The goal of the open-label extension period was to better understand the long-term administration of UPLIZNA beyond the 28-week time frame that was originally studied in the randomized controlled period of the trial,” 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. “These data are important because they provide further evidence that UPLIZNA can safely be used by NMOSD patients for an extended period of time, for at least four years, and that the medicine provides a sustained effect on attack risk.”

Outcomes Maintained Throughout the Four-Year Open-Label Period

The N-MOmentum Phase 2/3 clinical trial consisted of a 28-week randomized controlled period (RCP), where study participants received UPLIZNA or placebo. Following the completion of this period, patients could enter into the OLP for at least two years, during which all patients (n=216) received UPLIZNA 300 mg every six months, with follow-up visits at Weeks 2, 4, 13, 26 and 39 of the OLP and every 26 weeks thereafter.

Key OLP findings include (P15.076)*:

• Long-term UPLIZNA treatment provided a sustained reduction in NMOSD attack risk from baseline, regardless of when treatment was initiated: 87.7 percent of patients who originally received UPLIZNA in the RCP (n=165) and 83.4 percent of patients who originally received placebo in the RCP (n=51) remained attack-free during the OLP for at least four years.
• The vast majority of attacks occurred in the first year of treatment.
• UPLIZNA treatment was associated with lesion reduction shown by MRI. The mean number of active lesions was similar during the OLP to the number observed in patients who received UPLIZNA during the RCP.

Key OLP safety findings include (P15.100)*: