Long Term Safety Study of SyB L-1101 in Patients With Recurrent/Relapsed or Refractory Myelodysplastic Syndrome (MDS) - Extension Study

SyB L-1101 (rigosertib sodium) will be administered intravenously 72 continuous hours (3 days), followed by 25-day observation period. The treatment period of 28 days (3 days of administration + 25 days of observation) constitutes 1 cycle. The dose at cycle 8 in the study 2011005 will be the dose (if needed, the dose can be reduced) at the first cycle in this study (cycle 9). From cycle 10 on, the dose of SyB L-1101 will be reduced, delayed, or discontinued according to adverse events and results of observation at the previous cycle.