Another clinical trial found that EPO + ATRA could be used to treat patients with MDS anemia in whom erythropoiesis-stimulating agents (ESAs) alone were ineffective, but not in patients with high levels of endogenous EPO, and it did not improve neutropenia or thrombocytopenia (Itzykson et al., 2009). Here, EPO is linked to myelodysplastic syndrome.