Study of Lonafarnib Versus Placebo in Subjects With Either Myelodysplastic Syndrome (MDS) or Chronic Myelomonocytic Leukemia (CMML) (Study P02978AM3)(TERMINATED)

Inclusion Criteria: Confirmed MDS (RA, RARS, RAEB, RAEB-T) or CMML according to FAB classification. Platelet transfusion dependence (requiring 1 to 8 platelet transfusion events every 4 week period (Day 84 to Day 57, Day 56 to Day 29, and Day 28 to Day 1) over an 8-week retrospective and 4-week prospective screening period). The individual number of platelet transfusion events during the three 4-weekly periods (Day 84 to Day -57; Day -56 to Day 29; Day -28 to Day -1) must not differ by greater more than 2 from the average number of platelet transfusion events during the 12 week screening period. If the subject is RBC transfusion dependent, the number of RBC transfusion events during the three 4-weekly periods (Days -84 to -57; Day -56 to Day 29 and Day -28 to Day -1) must not differ by more than 2 from the average number of RBC transfusion events during this 12 week screening period. ECOG PS 0-2. Exclusion Criteria: Subjects with chemotherapy/radiotherapy-associated secondary MDS. <12 Weeks (prior to Day-1 Randomization) from any investigational drug use, any chemotherapy, radiotherapy, immunotherapy and any other treatment or MDS/CMML other than best supportive care. Hx of bone-marrow or peripheral stem-cell transplantation or treatment with donor lymphocyte infusion. Hx of AML. Known hx of immune thrombocytopenic purpura. Marked baseline prolongation of QTc interval, CTCAE Grade >=1. Use of ketokonazole within 72 hours prior to study drug administration.