1. any physical examination findings and/or history of any illness that, in the opinion of the study investigator, might confound the results of the study or pose an additional risk to the patient 2. nursing women or women of childbearing potential (wocbp) with a positive pregnancy test 3. treatment with another dhodh inhibitor (e.g., leflunomide, teriflunomide) or other agents known to cause bone marrow suppression leading to thrombocytopenia 4. platelets ≤150,000 cell/mm3 5. hemoglobin \< 10 gm/dl 6. absolute neutrophil count \< 1500 cells/mm3 7. renal dysfunction, i.e., creatinine clearance \< 30 ml/min 8. ast or alt \> 2 x uln, or total bilirubin \> uln. gilbert's syndrome is allowed. 9. bleeding disorders or blood loss requiring transfusion in the six weeks preceding enrollment 10. ongoing gastrointestinal ulcer, or gastrointestinal bleeding within 6 weeks of randomization. 11. chronic hepatitis b infection, active hepatitis c infection, active liver disease and/or cirrhosis per subject report. 12. heart failure, current uncontrolled cardiovascular disease, including unstable angina, uncontrolled arrhythmias, major adverse cardiac event within 6 months (e.g. stroke, myocardial infarction, hospitalization due to heart failure, or revascularization procedure).

1. any physical examination findings and/or history of any illness that, in the opinion of the study investigator, might confound the results of the study or pose an additional risk to the patient 2. nursing women or women of childbearing potential (wocbp) with a positive pregnancy test 3. treatment with another dhodh inhibitor (e.g., leflunomide, teriflunomide) or other agents known to cause bone marrow suppression leading to thrombocytopenia 4. platelets ≤150,000 cell/mm3 5. hemoglobin \< 10 gm/dl 6. absolute neutrophil count \< 1500 cells/mm3 7. renal dysfunction, i.e., creatinine clearance \< 30 ml/min 8. ast or alt \> 2 x uln, or total bilirubin \> uln. gilbert's syndrome is allowed. 9. bleeding disorders or blood loss requiring transfusion in the six weeks preceding enrollment 10. ongoing gastrointestinal ulcer, or gastrointestinal bleeding within 6 weeks of randomization. 11. chronic hepatitis b infection, active hepatitis c infection, active liver disease and/or cirrhosis per subject report. 12. heart failure, current uncontrolled cardiovascular disease, including unstable angina, uncontrolled arrhythmias, major adverse cardiac event within 6 months (e.g. stroke, myocardial infarction, hospitalization due to heart failure, or revascularization procedure).

any physical examination findings and/or history of any illness that, in the opinion of the study investigator, might confound the results of the study or pose an additional risk to the patient nursing women or women of childbearing potential (wocbp) with a positive pregnancy test treatment with another dhodh inhibitor (e.g., leflunomide, teriflunomide) or other agents known to cause bone marrow suppression leading to thrombocytopenia platelets ≤150,000 cell/mm3 hemoglobin < 10 gm/dl absolute neutrophil count < 1500 cells/mm3 renal dysfunction, i.e., creatinine clearance < 30 ml/min ast or alt > 2 x uln, or total bilirubin > uln. gilbert's syndrome is allowed. bleeding disorders or blood loss requiring transfusion in the six weeks preceding enrollment ongoing gastrointestinal ulcer, or gastrointestinal bleeding within 6 weeks of randomization. chronic hepatitis b infection, active hepatitis c infection, active liver disease and/or cirrhosis per subject report. heart failure, current uncontrolled cardiovascular disease, including unstable angina, uncontrolled arrhythmias, major adverse cardiac event within 6 months (e.g. stroke, myocardial infarction, hospitalization due to heart failure, or revascularization procedure).

any physical examination findings and/or history of any illness that, in the opinion of the study investigator, might confound the results of the study or pose an additional risk to the patient nursing women or women of childbearing potential (wocbp) with a positive pregnancy test treatment with another dhodh inhibitor (e.g., leflunomide, teriflunomide) or other agents known to cause bone marrow suppression leading to thrombocytopenia platelets ≤150,000 cell/mm3 hemoglobin < 10 gm/dl absolute neutrophil count < 1500 cells/mm3 renal dysfunction, i.e., creatinine clearance < 30 ml/min ast or alt > 2 x uln, or total bilirubin > uln. gilbert's syndrome is allowed. bleeding disorders or blood loss requiring transfusion in the six weeks preceding enrollment ongoing gastrointestinal ulcer, or gastrointestinal bleeding within 6 weeks of randomization. chronic hepatitis b infection, active hepatitis c infection, active liver disease and/or cirrhosis per subject report. heart failure, current uncontrolled cardiovascular disease, including unstable angina, uncontrolled arrhythmias, major adverse cardiac event within 6 months (e.g. stroke, myocardial infarction, hospitalization due to heart failure, or revascularization procedure).

1. any physical examination findings and/or history of any illness that, in the opinion of the study investigator, might confound the results of the study or pose an additional risk to the patient 2. nursing women or women of childbearing potential (wocbp) with a positive pregnancy test 3. treatment with another dhodh inhibitor (e.g., leflunomide, teriflunomide) or other agents known to cause bone marrow suppression leading to thrombocytopenia 4. platelets ≤150,000 cell/mm3 5. hemoglobin < 10 gm/dl 6. absolute neutrophil count < 1500 cells/mm3 7. renal dysfunction, i.e., creatinine clearance < 30 ml/min 8. ast and/or alt > 2 x uln, or total bilirubin > uln. gilbert's syndrome is allowed. 9. bleeding disorders or blood loss requiring transfusion in the six weeks preceding enrollment 10. ongoing gastrointestinal ulcer, or gastrointestinal bleeding within 6 weeks of randomization. 11. chronic hepatitis b infection, active hepatitis c infection, active liver disease and/or cirrhosis per subject report. 12. heart failure, current uncontrolled cardiovascular disease, including unstable angina, uncontrolled arrhythmias, major adverse cardiac event within 6 months (e.g. stroke, myocardial infarction, hospitalization due to heart failure, or revascularization procedure).

1. any physical examination findings and/or history of any illness that, in the opinion of the study investigator, might confound the results of the study or pose an additional risk to the patient 2. nursing women or women of childbearing potential (wocbp) with a positive pregnancy test 3. treatment with another dhodh inhibitor (e.g., leflunomide, teriflunomide) or other agents known to cause bone marrow suppression leading to thrombocytopenia 4. platelets ≤150,000 cell/mm3 5. hemoglobin < 10 gm/dl 6. absolute neutrophil count < 1500 cells/mm3 7. renal dysfunction, i.e., creatinine clearance < 30 ml/min 8. ast and/or alt > 2 x uln, or total bilirubin > uln. gilbert's syndrome is allowed. 9. bleeding disorders or blood loss requiring transfusion in the six weeks preceding enrollment 10. ongoing gastrointestinal ulcer, or gastrointestinal bleeding within 6 weeks of randomization. 11. chronic hepatitis b infection, active hepatitis c infection, active liver disease and/or cirrhosis per subject report. 12. heart failure, current uncontrolled cardiovascular disease, including unstable angina, uncontrolled arrhythmias, major adverse cardiac event within 6 months (e.g. stroke, myocardial infarction, hospitalization due to heart failure, or revascularization procedure).