Efgartigimod in Sjögren's Disease: Phase 2 RHO Trial Results
Key Takeaways
- At week 24, CRESS response was higher with intravenous efgartigimod than with placebo.
- cSTAR response also favored efgartigimod, which scored higher on four of five CRESS items.
- Treatment-emergent adverse events were more common with efgartigimod, all were grade 1 or 2, and the authors said the findings support proof of concept and further phase 3 evaluation.
The multicenter RHO study randomly assigned 34 adults with Sjögren's disease in a 2:1 ratio to intravenous efgartigimod or placebo. Twenty-three participants received efgartigimod 10 mg/kg once weekly for 24 weeks, and 11 received placebo. The week 24 efficacy analysis included 31 participants and covered both efficacy endpoints. The primary endpoint was week 24 CRESS response on at least three of five items, covering systemic disease activity, symptoms, tear and salivary gland function, and serology. The secondary outcome was a week 24 cSTAR score of at least 5; safety was also assessed, and no formal statistical hypothesis was tested.
For the primary endpoint, the week 24 treatment difference was 34.4% in favor of efgartigimod. Efgartigimod also scored higher on four of the five CRESS items evaluated at week 24. For cSTAR, 54.5% of efgartigimod-treated participants reached a score of at least 5 at week 24, compared with 33.3% of placebo-treated participants. Across the reported week 24 efficacy measures, the results favored efgartigimod over placebo.
Treatment-emergent adverse events occurred in 87.0% of the efgartigimod group and 63.6% of the placebo group. All reported events were grade 1 or 2 over the 24-week treatment period. Authors interpreted the combined week 24 findings as supporting proof of concept and as warranting further phase 3 evaluation in Sjögren's disease.