Pharmacokinetic Guided Dose Escalation and Dose Confirmation With Oral Decitabine and Oral Cytidine Deaminase Inhibitor (CDAi) in Patients With Myelodysplastic Syndromes (MDS)

Mean AUC0-t of oral decitabine given with cedazuridine (E7727) following IV decitabine 20 mg/m^2 infusion on Day 5. AUCs were calculated by the linear up/log down method using the measured concentration-time values above the BQL (below the limit of quantification).

Decitabine 5-day AUC ratio following IV decitabine 20 mg/m^2 infusion versus concomitant oral administration of decitabine + cedazuridine (E7727) or ASTX727 in the dose combination and fixed-dose combination stages, respectively. AUC0-t (the area under the concentration-time curve from time zero to the time of the last (tlast) quantifiable concentration (Ct)) by dose/cohort and course/days was used for estimating decitabine cumulative 5-day AUC0-t exposures.

Number of participants with protocol-specified dose-limiting toxicities (DLTs) in the dose escalation stage. DLTs were defined using the Common Terminology Criteria for Adverse Events Version 4.0 (CTCAEv4.0), specifically ≥ Grade 3 non-hematologic toxicity (except Grade 3 nausea, vomiting, or diarrhea that is controllable by anti-emetics or optimal therapy or related to underlying disease or disease progression), specific Grade 3 laboratory tests, related prolonged Grade 4 thrombocytopenia or neutropenia that was not present prior to dosing, does not resolve within 14 days, and is not related to underlying disease, or any toxicity related to study treatment that results in treatment delays of >4 weeks after Day 28.

Mean maximum % long interspread nuclear element-1 (LINE-1) demethylation after oral decitabine + cedazuridine (E7727) or ASTX727 (Course 1 or Course 2 - Treatment) compared with IV decitabine 20 mg/m^2 (Course 1 or Course 2 - IV Decitabine) in the dose confirmation and fixed-dose combination stages, respectively. Least squares mean of maximum %LINE-1 methylation change from baseline.

The evaluation of response was based on International Working Group (IWG) 2006 MDS Response Criteria, with overall response calculated as number of participants with complete response+partial response+marrow complete response+hematological improvement (CR+PR+mCR+HI).

AUC is a measure of the plasma concentration of the drug over time (AUC0-8). PK parameters are reported for the dose escalation stage by cohort in Phase 1 and dose confirmation and fixed-dose combination stages in Phase 2.

Cmax is the maximum observed plasma concentration. PK parameters are reported for the dose escalation stage by cohort in Phase 1 and dose confirmation and fixed-dose combination stages in Phase 2.

Tmax is the time to maximum observed plasma concentration. PK parameters are reported for the dose escalation stage by cohort in Phase 1 and the dose confirmation and fixed-dose combination stages in Phase 2.

Cmax is the maximum observed plasma concentration. PK parameters for plasma decitabine are reported for the dose escalation stage by cohort in Phase 1 and dose confirmation and fixed-dose combination stages in Phase 2.

Tmax is the time to reach maximum plasma concentration for decitabine. PK parameters for plasma decitabine are reported for the dose confirmation and fixed-dose combination stages.

Duration of response (in number of days) was calculated from the first time the response was observed to time of relapse or last time point in the study.

Duration of response (in number of days) was calculated from the first time the response was observed to time of relapse or last time point in the study. Kaplan-Meier estimate for complete response is shown.

Mean maximum % long interspread nuclear element-1 (LINE-1) demethylation decrease from baseline after oral decitabine + cedazuridine (E7727) or ASTX727 compared with IV decitabine 20 mg/m^2 in the dose escalation stage.

The evaluation of response was based on International Working Group 2006 MDS Response Criteria, with overall response calculated as number of participants with complete response+partial response+marrow complete response+hematological improvement (CR+PR+mCR+HI).

Number of participants with any treatment-emergent adverse event (AE) and any AE graded ≥3 using Common Terminology Criteria for Adverse Events (CTCAE) version 4.0.

Hematological improvement was calculated as defined by the IWG 2006 MDS Response Criteria.

Transfusion independence was calculated based on the number of transfusion-dependent participants at baseline who had no red blood cell or platelet transfusions for 56 consecutive days or more after treatment.

Number of participants to reach the event (AML or death), where time to reach AML was calculated as the number of days from the day the participant received the first dose of IV decitabine, oral decitabine + E7727, or the FDC tablet to the date of death or the date of MDS progression to AML as defined by ≥20% blasts in bone marrow or peripheral blood using the World Health Organization classification. Time to AML or death was censored on the last date of contact if a participant was lost to follow up prior to reaching a time-to-event endpoint.

Overall survival was defined as the number of days from the day the participant received the first dose of IV decitabine, oral decitabine + E7727, or the FDC tablet to the date of death, regardless of cause.