A phase 1 clinical trial evaluated H3B-8800, which is a small molecule that binds to splicing factor 3B1 (SF3B1), in patients with MDS, CMML, and AML (38/84 patients had AML); there were no complete/partial responses by 2006 IWG criteria, and, per author, in the four patients with SF3B1 mutations and AML, there were no RBC transfusion-independent periods [164]. The gene discussed is SF3B1; the disease is chronic myelomonocytic leukemia.