Reduced Steroid Use with Sarilumab for Polymyalgia Rheumatica

Polymyalgia rheumatica (PMR) ranks as the second most common inflammatory rheumatic disorder among individuals over the age of 50, with a higher prevalence in women. The lifetime incidence risk for women is approximately 2.4 percent, compared to 1.7 percent for men. Typical symptoms include bilateral shoulder pain, low-grade fever, fatigue, and prolonged morning stiffness.

The standard first-line treatment for PMR involves glucocorticoids, which most patients respond to positively. In cases of stable remission, it is recommended to gradually taper the glucocorticoid dosage until complete withdrawal is achieved. However, many patients experience relapses, complicating the goal of discontinuing glucocorticoid therapy. Consequently, long-term steroid use may be necessary, which carries known side effects.

Currently, the 2017 German guidelines recommend off-label use of methotrexate as a glucocorticoid-sparing agent for difficult-to-treat patients. However, the evidence for its effectiveness in PMR is inconclusive, as noted in a press release from Sanofi, the manufacturer of Kevzara, a drug that has recently been approved for PMR treatment.

Sarilumab, an IL-6 receptor antagonist, has been previously approved for treating moderate to severe active rheumatoid arthritis. Recently, this antibody received approval in the European Union for treating PMR in adult patients who do not respond adequately to corticosteroids or experience a relapse during corticosteroid tapering. This approval is based on findings from the SAPHYR study, which demonstrated that a significantly higher percentage of patients in the Sarilumab group achieved sustained disease remission compared to those receiving a placebo after 52 weeks (28% vs. 10%).

The recommended dosage for Sarilumab is 200 mg administered subcutaneously every two weeks, in conjunction with a tapering regimen of systemic corticosteroids. Following the tapering process, Sarilumab can be continued as a monotherapy.

Common side effects associated with Sarilumab in the context of rheumatoid arthritis and PMR include neutropenia, upper respiratory infections, elevated alanine aminotransferase levels, urinary tract infections, and injection site erythema.