How We Treat Hemolytic Anemia Due to Pyruvate Kinase Deficiency.

backgroundPyruvate kinase (PK) deficiency is an inherited red blood cell (RBC) enzyme disorder that results in non-immune chronic hemolytic anemia. Characteristic symptoms of PK deficiency include anemia, fatigue, splenomegaly, jaundice, gallstones, thrombosis, and transfusional iron overload. Previously, treatments aimed at symptomatic management with RBC transfusions, phototherapy, folic acid supplementation, splenectomy, and iron chelation therapy when iron overload was documented. Mitapivat, a recently approved medication for treatment of PK-deficiency hemolytic anemia, is an oral allosteric activator of wild-type and mutant RBC PK enzymes. In this paper, we describe three cases of PK-deficiency anemia treated with mitapivat and describe modern management of this rare hemolytic disorder.

methodsA retrospective healthcare database analysis was conducted to extract relevant information. Both quantitative and qualitative methods were integrated to provide a more comprehensive understanding of the cases.

resultsTwo patients responded well to treatment with mitapivat, noted by an increase in hemoglobin levels, improvements in hemolytic markers, less frequent or no RBC transfusion requirements, and improvements in fatigue. One patient carrying two non-missense mutations of the

conclusionsWhile mitapivat addresses the previously unmet needs of most patients with PK deficiency as the first and only disease-modifying medication to receive approval for this condition, not all patients with PK deficiency are amenable to treatment with mitapivat.