Luspatercept Therapy in Hematology

Luspatercept is a recombinant fusion protein of activin receptor type two B extracellular domain joined to human IgG Fc that binds and neutralizes select TGF beta superfamily ligands including GDF11. Inhibition of these ligands relieves blocked late stage erythroid maturation in ineffective erythropoiesis allowing increased mature red cell production and reduced transfusion need.

Approved indications include adults with beta thalassemia who require regular red cell transfusions, adults with very low risk to intermediate risk myelodysplastic syndrome with ring sideroblasts or SF3B1 mutation refractory to erythropoiesis stimulating agents, and most recently transfusion dependent myelodysplasia in selected risk categories. The drug is administered subcutaneously every three weeks at doses titrated by hemoglobin response.

Adverse effects include fatigue, headache, bone pain, hypertension, peripheral edema, and increased thromboembolic risk especially in beta thalassemia. Pretreatment evaluation excludes other anemia causes, addresses iron status, and confirms vaccination. Response is assessed at six months as transfusion independence or hemoglobin rise above one and a half grams per deciliter without transfusion.