EULAR: Sarilumab investigational anti-IL-6R therapy shows positive results in rheumatoid arthritis treatment in study

Sanofi and Regeneron Pharmaceuticals presented positive results from a phase 3 trial of investigational drug sarilumab in rheumatoid arthritis (RA) patients who were inadequate responders to methotrexate (MTX) therapy at the European League Against Rheumatism Annual Congress (EULAR 2014) Congress in Paris, France. 

Sarilumab is an investigational human monoclonal antibody targeting interleukin-6 receptor (IL-6R).

In the MOBILITY phase 3 study, 1,197 RA patients were randomly assigned to receive sarilumab 200 mg, sarilumab 150 mg, or placebo every other week, all in combination with MTX. The MOBILITY trial was designed to demonstrate that sarilumab on top of MTX is effective in reducing signs and symptoms, improving physical function and inhibiting the progression of structural damage in patients with RA.

Both sarilumab groups showed clinically relevant and statistically significant improvements compared to the placebo group in all 3 co-primary end points (P<.0001), showing:

• Improvement in signs and symptoms of RA at 24 weeks, as measured by American College of Rheumatology score of 20% improvement (ACR20)

• Improvement in physical function, as measured by change from baseline in the Health Assessment Question-Disability Index (HAQ-DI) at week 16.

• Inhibition of progression of structural damage at Week 52, as measured by the change in the modified Van der Heijde total Sharp score (mTSS)

“In the trial, sarilumab was seen to be safe and generally well tolerated,” said Tanya Momtahen, VP, Anti-IL6R Project Unit Head, Sanofi. “The safety findings were consistent with those observed in prior investigational studies with sarilumab.”

The MOBILITY phase 3 study results are the first results in a large ongoing phase 3 program.

“We feel that these results are encouraging and demonstrate the potential that sarilumab may offer as a new alternative for physicians to treat patients suffering with RA,” said Janet van Adelsberg, senior director, immunology and inflammation, Regeneron. “We look forward to presenting further study results in 2015, which are needed to answer this question.”

Further phase 3 studies of sarilumab are under way and aim to provide additional evidence that sarilumab anti-IL-6R therapy delivered via a subcutaneous injection every other week may be a future option for RA patients.

“Despite available treatment options, 20% to 40% of patients have an inadequate response, demonstrating the need for additional therapeutic options to treat RA,” according to Momtahen.