Pre-Clinical Use of Rituximab Forestalls Rheumatoid Onset Save

The results of the PRAIRI study were presented today at EULAR 2016 in London. These early findings suggest that individuals "at-risk" to develop rheumatoid arthritis (RA) may benefit from a short course of intravenously rituximab therapy.

Gerlag and investigators from the Netherlands enrolled 82 "pre-clinical" patients, unified by having arthralgias and RF and CCP positiviity along with a C-reactive protein (CRP) >0.6 mg/L or subclinical synovitis (either by ultrasound or MRI). At-risk individuals were excluded if they had ever received a DMARD or biologic drug or recent steroid therapy. These patients had no tender or swollen joints and many were first degree relatives of an RA patient.

Subjects were enrolled in a multicentre, double-blind, placebo-controlled clinical trial and were randomized to receive a single iv infusion of either placebo or 1000 mg rituximab (all received 100 mg methylprednisolone premedication).

Patients were followed until the onset of arthritis (primary endpoint). With a median follow up of 27 months, 30 subjects developed arthritis; moreso in the placebo group (40%) than those on rituximab (34%). The median time to arthritis onset was 11.5 months with placebo and 16.5 months in the rituximab group.

After 18 months, being rituximab treated reduced the risk of arthritis onset by 53%. Longer follow-up is needed to realize the full impact of this suppressive effect.

Rituximab is but one of several immunomodulators (including hydroxychloroquine, abatacept) under study as a disease modifying therapy for those with "pre-clinical" RA.