Sanofi and Regeneron Pharmaceuticals, Inc. presented positive results from a phase III trial of the investigational drug sarilumab in rheumatoid arthritis (RA) patients who were inadequate responders to methotrexate (MTX) therapy.
Sanofi and Regeneron Pharmaceuticals, Inc. presented positive results from a phase III trial of the investigational drug sarilumab in rheumatoid arthritis (RA) patients who were inadequate responders to methotrexate (MTX) therapy.
New data presented at the European League Against Rheumatism (EULAR) Congress in Paris, France, showed that sarilumab increased major clinical response rates defined as achieving an American College of Rheumatology score (ACR70 response) for at least 24 consecutive weeks and showed sustained improvement in signs and symptoms of RA after 52 weeks, which were secondary endpoints of the trial.
In this study, called SARIL-RA-MOBILITY, sarilumab met all three co-primary endpoints, demonstrating improvement in disease signs and symptoms at 24 weeks, physical function at 16 weeks and inhibition of joint damage progression at 52 weeks.
“Despite notable advances, many RA patients continue to struggle with debilitating signs and symptoms, underscoring a clear need for additional options,” said Dr Mark Genovese, Professor, Stanford University Medical Center and lead investigator in the study. “Sarilumab showed efficacy in this study at two different doses, both delivered subcutaneously every other week. We look forward to the results of ongoing trials in this comprehensive registration program.”
The SARIL-RA-MOBILITY phase III trial enrolled 1,197 adult patients with active, moderate-to-severe RA, who were inadequate responders to MTX therapy. Patients were randomized to one of three treatment groups dosed subcutaneously every other week, sarilumab 150 mg, sarilumab 200 mg or placebo, all in combination with MTX.
Both sarilumab groups showed statistically significant improvements compared with the placebo group in all three co-primary endpoints (p<0.0001).
1. Improvement in signs and symptoms of RA at 24 weeks, as measured by the ACR score of 20% improvement (ACR20). These results were 58%, 66% and 33% in the sarilumab 150 mg, sarilumab 200 mg and placebo groups, respectively, all in combination with MTX.
2. Improvement in physical function at week 16 as measured by Health Assessment Questionnaire – Disability Index (HAQ-DI). Newly presented HAQ-DI results were –0.53, –0.55 and –0.29 in the sarilumab 150 mg, sarilumab 200 mg and placebo groups, respectively, all in combination with MTX.
3. Inhibition of progression of structural damage at week 52, as measured by changes in the van der Heijde modified total Sharp score (mTSS). These results were 0.90, 0.25 and 2.78 in the sarilumab 150 mg, sarilumab 200 mg and placebo groups, respectively, all in combination with MTX. The group receiving the 200 mg dose of sarilumab + MTX had a reduction of approximately 90% in the radiographic progression assessed by the mTSS compared with the radiographic progression with placebo + MTX at week 52.
Also newly presented, both sarilumab groups also showed improvement on the major clinical response secondary endpoint:
- Sarilumab combined with MTX demonstrated a statistically significantly greater effect than MTX alone in achieving a major clinical response, defined as reducing signs and symptoms of RA by 70% or more, as measured by improvement of ACR70, for at least 24 consecutive weeks. These results were 13%, 15% and 3% in the sarilumab 150 mg, sarilumab 200 mg and placebo groups, respectively (p<0.0001).
Both doses also demonstrated a sustained response in improvement of signs and symptoms of RA compared with placebo at 52 weeks as measured by the ACR20 response. These results were 54%, 59% and 32% in the sarilumab 150 mg, sarilumab 200 mg and placebo groups, respectively.
In the SARIL-RA-MOBILITY trial, there was a higher incidence of treatment-emergent adverse events leading to withdrawal in the sarilumab treatment groups compared with placebo (12.5% in 150 mg, 13.9% in 200 mg and 4.7% in placebo). Infections were the most frequently reported adverse events and were reported with a higher incidence in the sarilumab groups compared with placebo, all in combination with MTX (40.1% for 150 mg, 39.6% for the 200 mg group and 31.1% for placebo). The incidence of serious infections was 2.6% in the 150 mg + MTX group, 4.0% in the 200 mg + MTX group and 2.3% in the placebo + MTX group.
Among patients treated with sarilumab, a dose-dependent decrease in mean neutrophil counts was observed. Serious infections were not associated with grades 3 and 4 neutropenia in this study. Increases in mean low-density lipoprotein (LDL) cholesterol, and transaminases were observed. These safety findings were consistent with those observed in prior investigational studies with sarilumab.
The sarilumab phase III programme, known as SARIL-RA, has six ongoing clinical studies and is targeted to enrol approximately 2,800 RA patients.
