Age ≥18 years.
Histological confirmation of WHO-defined diagnosis of proliferative CMML (WBC count ≥ 13,000/mm^3).
Relapsed/refractory following treatment with hydroxyurea; or at least 4 cycles of treatment with hypomethylating agents; or who are intolerant of treatment with either therapy. Note: Prior exposure to erythropoiesis stimulating agents is allowed. Hydroxyurea may continue for the first 28 days on study. Continuation of hydroxyurea beyond the first cycle must be discussed with the PI.
Willing and able to review, understand, and provide written consent before starting any study-specific procedures or therapy
Willing to return to enrolling institution for follow-up (during the Active Monitoring Phase of the study).
Willingness to provide mandatory bone marrow specimens for correlative research (see Section 14.0).
ECOG Performance Status (PS) 0, 1 or 2 (Appendix I)
Recovered to Grade 1 or baseline or established as sequelae from all toxic effects of previous therapy except alopecia.
The following laboratory values obtained ≤ 14 days prior to pre-registration:
Platelet count ³ 20,000/mm^3;
Total bilirubin ≤1.5 x ULN (≤ 3 x ULN for patients with Gilbert’s syndrome);
Alanine aminotransferase (ALT) and aspartate transaminase (AST) ≤ 3 x ULN;
Estimated glomerular filtration rate (eGFR) ³ 60 mL/min/m2 using the Cockcroft-Gault formula below:
Ability to complete questionnaire(s) by themselves or with assistance.
Willingness to provide mandatory blood specimens for correlative research (see Section 14.0).
Previous exposure to an alternative (investigational) PLK1 inhibitor.
MDS/MPN overlap syndromes other than CMML.
Prior allogeneic hematopoietic stem cell transplantation.
Active central nervous system disease.
Concurrent active malignancy, except adequately treated nonmelanoma skin cancer. History of curatively treated in situ cancer of the cervix, curatively treated in situ cancer of the breast, or other solid tumors curatively treated is allowed as long as there is no evidence of disease for > 2 years.
New York Heart Association (NYHA) class III/IV heart failure or active angina/angina equivalents (Appendix II).
Anticancer chemotherapy or biologic therapy administered within 2 weeks (and at least 4 elimination half-lives for clinical trial agents) prior to pre-registration.NOTE: Hydroxyurea is allowed for the first 28 days on study. Continuation of hydroxyurea beyond the first cycle must be discussed with the PI.
Receiving any other investigational agent which would be considered as a treatment for the primary neoplasm.
Major surgery ≤6 weeks prior to pre-registration.
Gastrointestinal (GI) disorder(s) that, in the opinion of the Investigator, would significantly impede the absorption of an oral agent (eg, intestinal occlusion, active Crohn’s disease, ulcerative colitis, extensive gastric and small intestine resection).
Unable or unwilling to swallow study drug.
Uncontrolled intercurrent illness including, but not limited to, ongoing or active infection, clinically significant nonhealing or healing wounds, clinically significant cardiac arrhythmia, significant pulmonary disease (shortness of breath at rest or mild exertion), uncontrolled infection, or psychiatric illness/social situations that would limit compliance with study requirements.
Known active infection with human immunodeficiency virus (HIV) with measurable viral titer, hepatitis B surface antigen positivity, or hepatitis C with measurable viral titer.
Patient is receiving any live vaccine (eg, varicella, pneumococcus) ≤ 28 days prior to pre-registration . NOTE: mRNA-based (eg, Pfizer or Moderna) or replication-deficient virus (eg, Oxford/AstraZeneca) COVID19 vaccines are permitted.
Disease requiring systemic treatment with systemic immunosuppression with steroid steroids at a dose of ≥ 20 mg/day prednisone (or equivalent). Exceptions: Intermittent use of bronchodilators or inhaled steroids, local steroid injections, topical steroids.
Any active disease condition that would render the protocol treatment dangerous or impair the ability of the patient to receive study drug.
Strong CYP3A4 inhibitors/inducers as identified per institutional guidelines. Comprehensive list can be found at https://drug-interactions.medicine.iu.edu/.
QT interval with Fridericia’s correction (QTcF) > 470 milliseconds. In the case of potentially correctible causes of QT prolongation, (eg, medications, hypokalemia), the ECG may be repeated once during Screening and that result may be used to determine eligibility.