XBiotech Pauses Rheumatology program

Core Insights - XBiotech has halted its clinical program in rheumatological diseases following the failure of its Phase II study in Rheumatoid Arthritis to meet primary endpoints, with significant irregularities complicating the interpretation of results [1][2] Company Overview - XBiotech is focused on the discovery and development of therapeutics utilizing its True Human antibody technology, with candidate products like Natrunix derived from individuals with natural immunity to certain diseases [3] Study Details - The Phase II study involved approximately 230 subjects with moderate to severe rheumatoid arthritis, assessing Natrunix in combination with methotrexate (MTX) [5] - The primary endpoint was the American College of Rheumatology (ACR) 20 response rate after 12 weeks, alongside various rheumatological assessments [5] - The study population was randomized into three groups: 200 mg or 400 mg Natrunix weekly with MTX, or placebo with MTX [5] Irregularities and Analysis - Irregularities in the Phase II study included multiple enrollments of subjects at the highest enrolling clinical sites, raising caution in interpreting the efficacy results [2] - Ongoing analysis of the findings aims to clarify the implications and guide future rheumatology studies for Natrunix [2]