Steroid-Sparing Rituximab in Polymyalgia Rheumatica Save

BRIDGE-PMR proof-of-concept trial assessed the efficacy of rituximab (RTX) in patients with polymyalgia rheumatica (PMR) and showed that a single 1000 mg dose of lead to a significant number of glucocorticoid-free remissions after 1 year. 

BRIDGE-PMR was a 21 week randomised controlled trial of 47 patients diagnosed with PMR according to EULAR/ACR classification criteria. The primary endpoint was glucocorticoid-free remission up to 1 year after infusion in an extension of this trial.

Patients randomly received eitehr placebo or 1000 mg rituximab IV, followed by accelerated glucocorticoid tapering over 17 weeks. After week 21, patients were followed in a double-blind extension until 1 year after infusion during which standard-of-care treatment was provided.  Glucocorticoid-free remission and disease activity were assessed using the polymyalgia rheumatica activity score [PMR-AS] <10.

Of the 47 patients enrolled, 38 were recently diagnosed with PMR and 9 had relapsing PMR; all with a mean age of 64 - 66 years. 

Glucocorticoid-free remission at 12 months was greater in the RTX group (52%), compared to the placebo group (21%; p=0·04.

Adverse events were similar between groups (26% vs 33%, respectively).

A single dose of rituximab (1000 mg) lead to a significantly higher rate of glucocorticoid-free remission at 1 year, suggesting the feasibility of this approach and need for further study.