Horizon Therapeutics plc announced the presentation of new MRI imaging data from the Phase 3 clinical trial showing UPLIZNA reduced the formation of subclinical (asymptomatic) optic nerve lesions in people with NMOSD. These findings are being presented during the 49(th) annual meeting of the North American Neuro-Ophthalmology Society (NANOS) March 11-16, 2023, in Orlando, Florida. UPLIZNA is the first and only B-cell depleting monotherapy approved by the U.S. Food and Drug Administration, the European Commission and the Brazilian Health Regulatory Agency (ANVISA) for the treatment of NMOSD in adults who are anti-aquaporin-4 immunoglobulin G seropositive (AQP4-IgG+).

The N-MOmentum pivotal trial (NCT02200770) is also the only Phase 3 clinical trial in NMOSD that collected MRI data and integrated MRI into its attack adjudication criteria. Results from the study demonstrated the significant effect of UPLIZNA in reducing the risk of NMOSD-associated attacks. This new post-hoc analysis based on MRI imaging provides a deeper understanding of the treatment effect on subclinical lesions.

The MRI findings showed that a high proportion of participants experienced subclinical optic nerve findings without new symptoms at the end of the RCP. These were shorter (median length 6 mm) than in those with an optic nerve attack (15 mm, p<0.001) and were not found to be associated with future attacks. Importantly, while the total subclinical findings in the optic nerve were not reduced during the RCP, the number of clinical optic neuritis attacks was significantly reduced during this time period.

Moreover, the formation of these subclinical findings was reduced with repeated UPLIZNA treatment over the course of the OLP.