SB1518 for Patients With Myelodysplastic Syndrome (MDS)

The goal of this clinical research study is to learn if SB1518 can help to control myelodysplastic syndrome. The safety of the drug will also be studied. SB1518 is designed to block JAK2 and FLT3. SB1518 may have anti-tumor activity in certain leukemias, myelofibrosis, and lymphoma.

Study Drug Administration: If you are found to be eligible to take part in this study, you will take SB1518 by mouth 1 time every day. You can take it with or without food, and it should be taken at the same time every day. You will receive your monthly supply of SB1518 during your clinic visit. The capsules should not be opened or crushed. Do not touch the powder in the capsules. If you do, wash effected areas thoroughly with water. Each study cycle is 28 days. Study Visits: At every study visit, you will be asked about any drugs you may be taking, and any side effects you have had. One (1) time a week during Cycle 1, blood (about 2 tablespoons) will be drawn for routine tests. On Day 1 of Cycles 2 and beyond, blood (about 2 tablespoons) will be collected for routine tests. On Day 28 of each cycle, you will have a bone marrow aspirate and/or biopsy to check the status of the disease. If the screening bone marrow test showed unusual genetic test results, these samples will be used for cytogenetic testing. If you have a response to therapy, you will have a bone marrow aspirate and/or biopsy every 3 cycles, if your doctor thinks it needed. Length of Study: You may continue taking the study drug for as long as the doctor thinks it is in your best interest. You will no longer be able to take the study drug if the disease gets worse, if intolerable side effects occur, you are able to undergo allogeneic bone marrow transplantation, or if you are unable to follow study directions. Your participation on the study will be over once you have completed the end-of-treatment visit. End-of-Treatment Visit: At 30 days after your last dose of study drug, you will have an end-of-treatment visit. You will be asked about any drugs you may be taking, and any side effects you have had. Blood (about 2 tablespoons) will be drawn for routine tests. You will have a bone marrow aspirate and/or biopsy to check the status of the disease, if your doctor thinks it is needed. This is an investigational study. SB1518 is not FDA approved or commercially available. It is currently being used for research purposes only. Up to 40 participants will take part in this study. All will be enrolled at MD Anderson.

Overall response based on hematologic improvement defined by International Working Group (IWG) response criteria in myelodysplasia. Complete remission (CR): Bone marrow of 5% myeloblasts with normal maturation of all cell lines, noted persistent dysplasia; Partial Remission: CR criteria if abnormal before treatment except Bone marrow blasts decreased by 50% over pretreatment but still > 5%; Marrow CR: Bone marrow 5% myeloblasts and decrease by 50% over pretreatment. Bone marrow aspirate pre-therapy (Day 0) and on Day 28 of first cycle then every 3 cycles. Responses must last at least 4 weeks.

Inclusion Criteria: Patients with MDS by the IPSS classification including low, int-1, int-2, and high risk are eligible. Patients should have received at least one line of prior therapy including growth factors, lenalidomide, or hypomethylating agents. Signed informed consent. Age >/= 18 years old. Patients must have the following non-hematologic values: Aspartate aminotransferase (AST/SGOT) and alanine aminotransferase (ALT/SGPT) </= 2.5 x Upper Limit of Normal (ULN) if both are available or </= 5.0 x ULN if hepatic involvement is present as determined by the investigator; Serum bilirubin </=2 x ULN; Serum creatinine </= 2 x ULN or 24-hour creatinine clearance >/= 50 ml/min Patients, if sexually active, must agree to use appropriate forms birth control. Exclusion Criteria: Uncontrolled intercurrent illness, including but not limited to ongoing active infection or psychiatric illness or social situations that the treating physician judges would limit compliance with study requirements. Patients receiving antibiotics for infections that are under control may be included in the study. History of myocardial infarction, severe/unstable angina, or symptomatic congestive heart failure within 6 months prior to study enrollment; New York Heart Association Class III or IV congestive heart failure; Ongoing cardiac dysrhythmias of Grade >/= 2, atrial fibrillation of any grade, QTc prolongation > 470 ms or other factors that increase the risk of QT prolongation (e.g., heart failure; hypokalemia, defined as serum potassium < 3.0 mEq/L; family history of long QT interval syndrome); Required use of a concomitant medication known to prolong the QT interval significantly. Known HIV seropositivity; Known active hepatitis A, B, or C; Women who are pregnant or lactating.