The US Food and Drug Administration (FDA) has approved Sobi’s Gamifant (emapalumab-lzsg) as the first-ever treatment for macrophage activation syndrome (MAS) in patients with Still’s disease.
The drug has been authorised to treat adult and paediatric patients with haemophagocytic lymphohistiocytosis (HLH)/MAS in known or suspected Still’s disease, including systemic juvenile idiopathic arthritis.
Eligible patients will need to have had an inadequate response to, or been unable to tolerate, glucocorticoids, or will have recurrent MAS.
MAS, a secondary form of HLH, is a severe complication of rheumatic disorders. It is characterised by high persistent fever, liver dysfunction, hepatosplenomegaly, cytopenias, coagulation abnormalities and hyperferritinaemia, and can potentially lead to multiple organ failure and death.
Given as an intravenous infusion, Gamifant is a monoclonal antibody that has been designed to neutralise interferon gamma, which causes hyperinflammation when secreted in an uncontrolled manner.
The drug is already approved in the US to treat primary HLH in adult and paediatric patients who have refractory, recurrent or progressive disease or an intolerance to conventional HLH therapy.
Sobi’s chief executive officer, Guido Oelkers, said: “With our expertise in primary HLH, we understand the urgency of managing MAS quickly to improve patient outcomes.
“Gamifant is already an established therapy making a meaningful difference for patients with primary HLH, and with this approval, we are excited about the opportunity to positively impact patients affected by MAS in Still’s disease”.
The FDA’s latest decision was supported by pooled study data showing that 54% of patients had a complete response at week eight, and 82% achieved clinical MAS remission at the same time point.
Also welcoming the authorisation, Alexei Grom, professor of paediatrics, research director division of rheumatology, Cincinnati Children’s Hospital Medical Center, said: “Many patients affected by MAS – both young children and adults – face significant unmet medical needs.
“With Gamifant now as the first FDA-approved treatment for MAS, we have a new therapeutic option that helps control hyperinflammation and reduce our reliance on high-dose glucocorticoids.”