Enasidenib is an oral targeted therapy used for acute myeloid leukemia (AML) that exerts its effects by blocking isocitrate dehydrogenase-2 (IDH2).
Mechanism of Action of Enasidenib
By blocking isocitrate dehydrogenase-2 (IDH2), Enasidenib facilitates the maturation of immature blood cells (blasts) within a patient's bone marrow into healthy, functional red blood cells, white blood cells, and platelets. Concurrently, it helps to alleviate the excessive accumulation of immature blood cells within the bone marrow.
FDA Approval of Enasidenib
In August 2017, the U.S. Food and Drug Administration (FDA) approved Enasidenib (marketed by Celgene) for the treatment of adult patients with relapsed or refractory acute myeloid leukemia (AML) who harbor an IDH2 mutation. Approximately 8% to 19% of AML patients carry an IDH2 mutation.
Enasidenib is the first drug in the class of IDH2 inhibitors. It specifically targets the mutant IDH2 variants R140Q, R172S, and R172K.
Efficacy of Enasidenib for the Treatment of AML
The efficacy of Enasidenib was validated in a single-arm clinical trial. This trial enrolled 199 patients with relapsed or refractory AML whose IDH2 mutation status was confirmed using the RealTime IDH2 assay.
After at least 6 months of treatment:
1. 19% of patients achieved a complete remission (defined as no evidence of disease following treatment and full recovery of blood cell counts), with a median duration of remission of 8.2 months. 2. Additionally, 4% of patients achieved a complete remission with partial hematologic recovery, with a median duration of remission of 9.6 months.
Among the 157 patients who required blood or platelet transfusions for acute myeloid leukemia (AML) at the time of enrollment, 34% no longer required transfusions after receiving treatment with Enasidenib.
Side Effects of Enasidenib
Common side effects of Enasidenib include nausea, vomiting, diarrhea, elevated bilirubin levels (a substance found in bile), and decreased appetite.
