A 15 Mg/M²/d Dose of Decitabine Confers Comparable Responses and Better Tolerance Than the Standard Regimen in MDS patients—results of a Multicenter Prospective Cohort Study

Abstract 3832

To further optimize the decitabine schedule for the treatment of myelodysplastic syndrome (MDS), a multicenter, prospective cohort study was performed. Out of 80 MDS patients, 46 were treated with a reduced dose of 15 mg/M²/d of decitabine by daily intravenous infusion for 5 consecutive days every 4 weeks. The remaining 34 patients were treated with the standard dose of 20 mg/M²/d of decitabine for 5 days every 4 weeks. All of the clinical and experimental baselines, as well as the course number used, were statistically comparable for the two groups. The results showed that the patients receiving the reduced dose of decitabine achieved statistically comparable overall response rate (ORR) (63% vs 71%), complete remission (CR) (30% vs 26%), cytogenetic CR (50% vs 46%) and overall survival (OS) (20.5 vs 19.6 months) compared with the standard dosage group. The decitabine concentration in the blood at a fixed time point after drug intake was decreased in the reduced-dose group but showed a similar degree of p15^ink4b grading for the responders in the two groups. A reduced dose caused less severe cytopenia, fewer cases of proven infection and a shorter median course interval (28 days vs 35 days in the standard-dose group). We concluded that a 15 mg/M²×5 day decitabine schedule yielded the same clinical benefit as the standard schedule and improved the bone marrow tolerance in this intermediate-sized cohort study. This trial was registered at www.clinicaltrials.gov as #ChiCTR-ONRC-12002004.