Core Insights - Rigel Pharmaceuticals announced the publication of five-year data from a Phase 2 trial of REZLIDHIA (olutasidenib) for treating relapsed or refractory mutant isocitrate dehydrogenase-1 acute myeloid leukemia (mIDH1 AML) [1][2] Efficacy and Safety Data - The five-year follow-up analysis supports the durable responses and manageable safety profile of olutasidenib, including efficacy in patients previously treated with venetoclax [2][5] - Among 147 efficacy evaluable patients, the complete remission (CR) or CR with partial hematologic recovery (CRh) rate was 35%, with a median duration of 25.3 months [5] - The overall response rate (ORR) was 48%, with a median duration of 15.5 months, and median overall survival (OS) was 11.5 months [5] - Transfusion independence was achieved in 39% of patients dependent on red blood cells and 41% of those dependent on platelets at baseline [5] Patient Response Insights - 66% of patients who achieved an overall response did so within 2 months, while 10% required at least 4.6 months of therapy [5] - Patients with one to two prior regimens had a higher CR/CRh rate of 41% and a median OS of 13 months compared to those with three prior regimens [5] - In patients R/R to prior venetoclax, 33% achieved a CR/CRh, with a median OS of 16.2 months [5] Ongoing Research and Collaborations - Rigel is evaluating olutasidenib in other disease areas and has strategic collaborations with The University of Texas MD Anderson Cancer Center [4][12] - A fifth study under the strategic alliance with MD Anderson has opened for enrollment, focusing on olutasidenib in combination with co-targeted therapies [12] Industry Context - Acute myeloid leukemia (AML) is a rapidly progressing cancer affecting myeloid cells, with an estimated 22,010 new cases in the U.S. in 2025 [6] - Relapsed AML affects about half of all patients post-treatment, while refractory AML occurs in 10-40% of newly diagnosed patients [7]