Rigosertib is a synthetic benzyl styryl sulfone analogue currently in phase III clinical trial for chronic myelomonocytic leukemia care (Garcia-Manero et al., 2016); it acts as a SMN2 splicing modifier, as suggested by a screening of small molecules carried out on C33A cell lines containing a SMN2-luciferase minigene reporter and SMA type I fibroblast cell lines (Son et al., 2019). The gene discussed is SMN2; the disease is chronic myelomonocytic leukemia.