Review of low-dose rituximab for retreatment of rheumatoid arthritis
Omer Hussein, Trevor Duffy, Maurice Barry
Rheumatology Department, Connolly Hospital Blanchardstown
Rituximab is a monoclonal antibody against CD20 which selectively depletes B-cells. It is effective in treatment of rheumatoid arthritis (RA) which is refractory to methotrexate and other biologics. There is a need to achieve sustained efficacy by repeated courses of rituximab. The licensed initial dose is course of two 1000 mg, however different retreatment doses have been studied. The low-dose of rituximab for retreatment showed no clear difference in outcomes from the higher dose. In our department in Connolly Hospital Blanchardstown we use the first course of rituximab as the licensed dose of two 1000 mg infusions, followed by low maintenance dose of single 500 mg infusion every six months.
We aim to evaluate the response of low maintenance dose of rituximab for treatment of rheumatoid arthritis in our department.
We reviewed charts of 24 patients of rheumatoid arthritis who are on rituximab maintenance therapy. We assessed the current dose and duration. Erythrocyte sedimentation rate (ESR) and C-Reactive protein (CRP) were recorded from last six months. Three patients had DAS28 reported.
Out of 24 patients, 22 patients are on 500 mg maintenance dose, one patient is on 750 mg and one patient is on 1000 mg dose. The average duration of the current dose is 37 months. The average for recent CRP is 5.45 (range 0.45 – 32.12) and for ESR is 20.16 (range 2 - 70). Two patients showed evidence of disease activity and their rituximab dose was increased. Three patients had their DAS28 recorded with low disease activity.
Maintenance low-dose rituximab treatment of our rheumatoid arthritis patients seems to be effective and maintains low disease activity. This is supported by the prolonged period of same dose (average duration of 37 months) and low inflammatory markers. Those patients will have to be followed to have their DAS28 reported. Using low dose could be cost-saving as well as using single dose which means a day less of hospitalization per patient.