Positive topline phase III results for Uplizna (inebilizumab-cdon) for the treatment of Immunoglobulin G4-related disease (IgG4-RD)

The trial met its primary endpoint , showing a statistically significant 87% reduction in the risk of IgG4-RD flare compared to placebo (Hazard Ratio 0.13, p<0.0001) during the 52-week placebo-controlled period. all key secondary endpoints were also met, which were annualized flare rate; flare-free, treatment-free complete remission; and flare-free, corticosteroid-free complete remission. no new safety signals were identified. the overall safety results during the placebo-controlled period of the trial were consistent with the known safety profile of uplizna.

Full data from the trial will be presented at a future medical meeting.

"MITIGATE is a landmark study with results that demonstrate an important advance in the treatment of patients with IgG4-RD, a devastating and rare disease that currently has no approved therapy," said Jay Bradner, M.D., executive vice president, Research and Development, and chief scientific officer at Amgen. "We are grateful for the partnership with patients, clinicians and patient advocacy groups critical to a successful study, and we look forward to bringing this therapy to those living with IgG4-RD."

MITIGATE was conducted at 80 sites in 22 countries. It is the first placebo-controlled trial providing class 1 evidence for treating IgG4-RD, a chronic, systemic, immune-mediated, fibroinflammatory disease that can affect almost any organ in the body, often involving multiple organs at a time, and can result in irreversible organ damage. The novel, steroid-sparing study design paves the way for a reduced toxicity treatment approach.

The trial was conducted with the support of Mitsubishi Tanabe Pharma and Hansoh Pharma. Mitsubishi Tanabe Pharma holds marketing authorization for Uplizna in Japan, Thailand, South Korea, Indonesia, Vietnam, Malaysia, Philippines, Singapore, and Taiwan. Hansoh Pharma is the exclusive licensee, local regulatory and commercial agent for China's mainland, Hong Kong, and Macau.

About the MITIGATE Trial: MITIGATE is a randomized, double-blind, placebo-controlled, parallel-group, multicenter trial designed to evaluate the efficacy and safety of Uplizna compared to placebo in reducing the risk of flares in adults with IgG4-RD. The trial enrolled 135 adults with IgG4-RD who met a robust assessment and central eligibility review. Eligibility criteria included multi-organ disease history and active disease being treated with glucocorticoids at the time of screening to ensure enrollment of a patient population at risk of flares for the primary endpoint. After a screening period of up to 28 days, patients were randomized (1:1) to receive 300 mg intravenous (IV) Uplizna or placebo on Days 1, 15, and Week 26 after premedication, and followed for the 52-week randomized control period.

The primary endpoint was time to first treated and adjudicated IgG4-RD flare. The three key secondary endpoints were annualized flare rate; flare-free, treatment-free complete remission; and flare-free, corticosteroid-free complete remission. The MITIGATE trial also includes an optional 3-year open-label treatment period and a safety follow-up period after Uplizna discontinuation of up to two years.