Positive Results Reported for Arthritis Drug Sarilumab in Phase III Trial
Treatment inhibits progression of joint damage (November 22)
In a phase III clinical trial involving adult patients with active rheumatoid arthritis (RA) who were inadequate responders to methotrexate (MTX), treatment with sarilumab (Sanofi/Regeneron Pharmaceuticals) — the first fully human anti-interleukin (IL)-6R monoclonal antibody — in combination with MTX improved the signs and symptoms of RA as well as physical function, and inhibited the progression of joint damage.
The 52-week SARIL-RA-MOBILITY trial included approximately 1,200 patients with active, moderate-to-severe RA who were inadequate responders to MTX therapy. The patients were randomly assigned to receive one of three subcutaneous treatments, all in combination with MTX and administered every other week: sarilumab 200 mg, sarilumab 150 mg, or placebo.
Both of the sarilumab groups showed clinically relevant and statistically significant improvements compared with the placebo group in all three co-primary endpoints (P < 0.0001): 1) improvement in the signs and symptoms of RA at 24 weeks, as measured by the American College of Rheumatology score of 20% improvement (ACR20); 2) improvement in physical function, as measured by the change from baseline in the Health Assessment Question–Disability (HAQ-DI) at week 16; and 3) inhibition of progression of structural damage at week 52, as measured by changes in the modified Van der Heijde Total Sharp Score (mTSS).
Key findings include the following:
- ACR20 improvement rates were 66%, 58%, and 33% for sarilumab 200 mg, sarilumab 150 mg, and placebo, respectively, all administered in combination with MTX.
- mTSS scores were 0.25, 0.90, and 2.78 for sarilumab 200 mg, sarilumab 150 mg, and placebo, respectively, all in combination with MTX.
- At week 52, patients receiving sarilumab 200 mg plus MTX showed a reduction of approximately 90% in radiographic progression, as assessed by the mTSS, compared with the radiographic progression seen in patients given placebo plus MTX.
Sarilumab is a subcutaneously delivered inhibitor of IL-6 signaling that binds with high affinity to the IL-6 receptor. The drug blocks the binding of IL-6 to its receptor and interrupts resultant cytokine-mediated inflammatory signaling.
Source: Sanofi; November 22, 2013.