The purpose of this study is to evaluate clinical efficacy and safety of arumakimig (MAS825) compared to placebo in patients with Vacuoles, E1 Enzyme, X-linked, Autoinflammatory, Somatic (VEXAS) syndrome. In addition, the study will evaluate the long-term efficacy, safety and tolerability of arumakimig in this population.
Male and female participants aged ≥18 years at screening.
Somatic mutation in UBA1 gene known to be associated with VEXAS.
Participants must have at least two manifestations of VEXAS at screening or in the past 6 months.
Participants must be able to start treatment for Pneumocystis jiroveci pneumonia (PJP) during the study if indicated according to the local guidelines.
Positive serology for hepatitis B surface antigen (HBsAg) excludes the participant.
Participants with a positive HCV antibody test should have HCV ribonucleic acid (RNA) levels measured. Participants with positive (detectable) HCV RNA must be excluded. Chronic hepatitis C patients who have completed HCV anti-viral treatment must be HCV-RNA negative at least 12 weeks after treatment before randomization to be eligible.
Active viral, bacterial, or other infections requiring systemic treatment at the time of screening or randomization, or history of recurrent clinically significant infection or of recurrent bacterial infections.
Known or suspected Human Immunodeficiency Virus (HIV) infection. Should it be required by local regulations and/or considered appropriate by the Investigator, an HIV test can be performed locally to confirm eligibility.
Parallel
Arumakimig
DrugArumakimig Injection
Placebo
DrugPlacebo Injection
Oral glucocorticoids
DrugBackground therapy with glucocorticoids. After the first 2 weeks of the study, participants may begin with glucocorticoid tapering depending on the disease status and the Investigator's judgement.
Number of participants achieving improvement of key VEXAS manifestations and oral glucocorticoid (GC) reduction at Week 52
Response is defined as meeting both criteria: A) Clinical domain: In participants with clinical disease activity in any domain at baseline, complete resolution of clinical manifestations related to active disease in at least one affected domain. In participants with no clinical disease activity in any domain at baseline, continued absence of clinical manifestations in all domains at Week 52. AND B) Protocol-defined glucocorticoid reduction through 52 weeks.
Number of participants achieving Overall Clinical Response (OCR) at Week 52
Achieving OCR at Week 52 is defined as meeting all the following criteria: * Absence of active inflammatory manifestations of VEXAS * Protocol-defined reduction in oral glucocorticoid. * Protocol-defined reduction in C reactive protein.
Number of participants achieving resolution of VEXAS manifestations
In participants with clinical disease activity in any domain at baseline, achieving complete resolution of clinical manifestations.
Number of participants with oral glucocorticoid reduction
Number of participants achieving protocol-defined glucocorticoid dose reduction through 52 weeks.
Total number of flare-free days over 52 weeks
Total cumulative number of days over 52 weeks meeting the protocol-defined criteria for a flare-free day.
Click on the lead sponsor to view all of their trials.
