Sutimlimab is a first-in-class monoclonal antibody in development for the treatment of cold agglutinin disease, a rare form of autoimmune haemolytic anaemia, caused by cold-reacting autoantibodies. These antibodies bind to red blood cell membranes and destroy them, leading to anaemia. Symptoms include chronic debilitating fatigue, acrocyanosis, shortness of breath and other anaemia-related symptoms, leading to a poor quality of life and increased health resource utilization. In chronic cold agglutinin disease, the patient is more symptomatic during winter months. Therapeutic options may range from using warm clothing and avoiding exposure to cold weather to blood transfusions and chemotherapy.
Sutimlimab takes a novel approach by binding to the cold-reacting autoantibodies and preventing them from attacking the red blood cells. Sutimlimab acts by selectively inhibiting one of the three complement pathways in the immune system leaving the other two pathways intact. This potentially preserves some of complement’s immune functions although it is unclear whether this would provide a clinical benefit and data from the clinical trials will be needed to better understand this. If approved, sutimlimab has the potential to become the first treatment option for cold agglutinin disease.
Romiplostim is a medicinal product that is being developed for the treatment of adult patients with idiopathic thrombocytopenic purpura (ITP) who are refractory to other treatments. ITP is the condition of having a low platelet count due to unknown cause. It is also known as immune thrombocytopenic purpura. Many people with ITP do not have symptoms, however people with very low platelet count can have symptoms such as pin prick rash, easy bruising, nosebleeds, gum bleeds, black mouth blisters, fatigue, and heavy periods. Most of the currently available treatments have significant side effects with some treatments leaving patients are at increased risk of infections.