Rituximab and Belimumab Combination Therapy in PR3 Vasculitis
Rituximab and Belimumab Combination Therapy in PR3 Vasculitis
Mechanistic study to assess whether dual B-cell immunotherapy by co-administration of
 rituximab and belimumab will result in improvements in biological endpoints, functional
 outcomes and clinical status compared to rituximab with placebo.
Inclusion Criteria:

 Participants must be 18 of age

 -  Have a diagnosis of AAV (granulomatosis with polyangiitis or microscopic polyangiitis)

 -  Have PR3 ANCA positivity by ELISA at screening

 -  Have active disease defined by one major or three minor disease activity items on
 BVAS/WG

 -  Be capable of giving signed informed consent

 Exclusion Criteria:

 -  MPO ANCA or anti-GBM antibody positivity by ELISA at screening

 -  Presence of pulmonary haemorrhage with hypoxia at screening

 -  Estimated glomerular filtration rate (eGFR) <30 ml/min/1.73m2 at screening

 -  Have an acute serious or chronic infection at screening

 -  Have received any B cell targeted therapy within 364 days of Day 1

 -  Have received any steroid injection (e.g., intramuscular [IM], intraarticular, or IV)
 within 60 days of Day 1 (unless given during or 14 days before screening period)

 -  Have received >1.5mg methylprednisolone (IV) between 14 days prior to screening and
 Day 1 (including Day 1).

 -  Have received oral prednisolone >10mg/day (or equivalent) on average over the 30 days
 prior to screening

 -  Have undetectable peripheral blood B cells at screening

 -  Have IgG <400mg/dl at screening