Extension Study With Tosedostat in Relapsed/Refractory Acute Myeloid Leukemia

Inclusion Criteria: * Signed, informed consent * Completion of Visit 11 in the OPAL Study (Month 6 Visit) * Investigator's opinion that the subject would benefit from continued therapy with tosedostat. Exclusion Criteria: * Any co-existing medical condition that in the Investigator's opinion will substantially increase the risk associated with the subject's participation in the study * Psychiatric disorders or altered mental status precluding understanding of the informed consent process and/or completion of the necessary studies * Administration of any (other) investigational agent within 14 days of entry into TOPAZ.