PRIMARY OBJECTIVES:~I. To determine the efficacy of LCL161 as therapy for primary myelofibrosis (PMF), post-polycythemia vera (PV) myelofibrosis (MF) and post-essential thrombocytosis (ET) MF.~II. To determine the objective response which is defined as CR (complete remission) + PR (partial remission) + CI (clinical improvement) after three cycles of treatment.~SECONDARY OBJECTIVES:~I. To determine the safety of LCL161 as therapy for PMF, post-PV MF and post-ET MF.~II. To determine time to response and response duration. III. To assess changes in symptom burden as assessed by Myeloproliferative Neoplasm Symptom Assessment Form Total Symptom Score (MPN-SAF TSS) and M.D. Anderson Symptom Inventory (MDASI) questionnaires.~EXPLORATORY OBJECTIVE:~I. To assess the mechanisms of action of LCL161 in patients with MF; these studies will include the analysis of baculoviral IAP repeat containing 2 (cIAP1), X-linked inhibitor of apoptosis, E3 ubiquitin protein ligase (XIAP), and poly (adenosine diphosphate [ADP]-ribose) polymerase 1 (PARP) protein levels which will be determined by western blot (actin as loading control) and will be measured at baseline and at beginning of each cycle for first 3 cycles and at end of study.~OUTLINE:~Patients receive SMAC mimetic LCL161 orally (PO) on days 1, 8, 15, and 22. Cycles repeat every 28 days in the absence of disease progression or unacceptable toxicity.~After completion of study treatment, patients are followed up for 30 days.
This phase II trial studies how well second mitochondrial-derived activator of caspases (SMAC) mimetic LCL161 (LCL161) works in treating patients with primary myelofibrosis, post-polycythemia vera myelofibrosis, or post-essential thrombocytosis myelofibrosis. SMAC mimetic LCL161 may help control the growth of abnormal cells by promoting apoptosis (programmed cell death).