LONDON -- An investigational monoclonal antibody drug for immunoglobulin (Ig)G4-related disease called obexelimab substantially outperformed placebo in the phase III INDIGO trial, researchers reported, positioning it to take on the only drug now specifically approved for the condition.
Time to first disease flare after starting therapy was more than halved with obexelimab, and twice as many patients obtained complete remission in the yearlong study, according to John Stone, MD, MPH, of Mass General Brigham in Boston, and colleagues.
Obexelimab also appeared to be reasonably well tolerated, with joint pain and diarrhea the most common adverse effects, the group reported in the New England Journal of Medicine. The study is also slated for presentation at the European Alliance of Associations for Rheumatology (EULAR) annual meeting, which starts this week.
Inebilizumab (Uplizna) was approved to treat IgG4-related disease in April 2025, making it the first and only drug with this specific indication. Corticosteroids have traditionally been the mainstay of therapy and are reasonably effective, but IgG4-related disease is lifelong and steroids' side effects with chronic use often become intolerable after a few years.
