New data for emapalumab in the treatment of macrophage activation syndrome to be presented at the ACR conference

The data were pooled from two open-label, single-arm interventional studies, the phase III  NI-0501-14 study [EMERALD; NCT05001737] and the phase II study NI-0501-06 [NCT03311854], including 39 patients with MAS.   These data will be presented by  Prof. Alexei A. Grom,  Research Director Division of Rheumatology, Cincinnati Children’s Hospital Medical Centre, in a session entitled “Efficacy and Safety of emapalumab in children and adults with macrophage activation syndrome (MAS) in Still’s disease: Results from a phase 3 study and a pooled analysis of two prospective trials” on Tuesday, 19 November at ACR Convergence.

Key results:

• i.Complete response at week 8: At week 8, 21 patients (53.8%) achieved a complete response (95% confidence interval (CI): 37.2–69.9%). ii. Complete response at any time: 33 patients (85%) achieved a complete response at any time during the studies. iii. Glucocorticoid tapering: Weekly mean glucocorticoid doses were reduced by 70.1% after 2 weeks of treatment. By week 8, glucocorticoids were tapered to a clinically meaningful dose of ≤1 mg/kg/day in 28 patients (72%) and to ≤0.5 mg/kg/day in 17 patients (44%). Safety: No new safety concerns were identified during the studies.

Additional key results:

• i. Overall response (OR) by week 8: 32 patients (82.4%) achieved an overall response by week 8. OR was observed as early as day 5, with a median time to first OR of 2.3 weeks.
• ii. .Clinical MAS remission: 32 patients (82.1%) achieved investigator-assessed clinical MAS remission at any time , with a median time to clinical remission of 3.3 weeks.
• iii.Survival rate: 37 patients (94.9%) were alive at week 8.

MAS in Still’s disease is a severe condition characterised by intense hyperinflammation and multiple organ failure. Those affected, including young children, often experience high fevers, liver and spleen enlargement, severe cytopenias, and neurological symptoms,” said Dr. Lydia Abad-Franch, Head of R&D and Medical Affairs and CMO at Sobi. “The results to be presented at ACR indicate that emapalumab could potentially provide a new therapeutic option, offering effective control of MAS symptoms and possibly reducing the need for high-dose glucocorticoids. This represents an important development in the treatment landscape for MAS.”