Antengene Corporation Limited announced the dosing of the first patient in China in a Phase I/II trial (the HATCH trial) of eltanexor (ATG-016), a next-generation selective inhibitor of nuclear export (SINE) compound, for the treatment of intermediate and higher-risk myelodysplastic syndrome (MDS) according to the Revised International Prognostic Scoring System (IPSS-R) after failed treatment with hypomethylating agent (HMA) based therapies. This single-arm, open-label clinical trial is designed to evaluate the safety and efficacy of eltanexor monotherapy in the prespecified patients with MDS. MDS is a malignancy originated in the bone marrow hemopoietic stem-cells of which the incidence increases significantly with age. The median overall survivals (OS) of patients with intermediate, high, and very high-risk MDS are 3, 1.6, and 0.8 years, respectively, and patients at these risk levels have a high probability of progressing to acute myeloid leukemia (AML). HMAs including azacytidine and decitabine are standard of care treatments for MDS. However, HMAs do not eradicate neoplastic clones and only generate response in around 50% of patients with MDS. Patients with MDS refractory to HMA-based therapies have a poor prognosis, limited options for follow-up treatment, and a median OS of only about four to six months. Eltanexor is a next-generation SINE compound, and an antagonist of the nuclear export protein XPO1, of which expression correlates with a poor prognosis and resistance to chemotherapies. Eltanexor induces apoptosis in tumor cells by inhibiting XPO1 and has demonstrated favorable anticancer activity in xenograft models of hematological malignancies and solid tumors. Data from a Phase I/II clinical study of eltanexor in patients with higher-risk MDS refractory to HMAs, as presented at the 2019 American Society of Hematology (ASH) Annual Meeting, have demonstrated an objective response rate (ORR) of 35%, with bone marrow complete response (mCR) achieved by all of those patients assessed as ORR. Meanwhile, these clinical results of eltanexor also showed a favorable safety and tolerability profile. In addition to MDS, eltanexor is also being investigated for the treatment of advanced solid tumors in China.