2015 ASH: Correlations Between Biomarkers and Clinical Responses in Phase 1/2 Study of Guadecitabine

Summary

Guadecitabine (SGI-110) is a novel subcutaneous (SC) next generation hypomethylating agent (HMA) designed as a dinucleotide of decitabine (DAC) and deoxyguanosine that is resistant to degradation by cytidine deaminase (CDA) and results in prolonged in vivo exposure to its active moiety DAC. The differentiated pharmacokinetic profile offers the potential of improved biological and clinical activity and safety over currently available HMAs.
In the Phase 1 study, patients with r/r AML were treated at escalating doses of guadecitabine. In the Phase 2 study, r/r AML patients were randomized to receive guadecitabine at 60 mg/m2 or 90 mg/m2 SC daily for 5 days (dailyx5). In a separate cohort, patients were treated with 60 mg/m2 SC daily for 10 days (dailyx10: days 1-5 and 8-12) for up to 4 cycles followed by subsequent cycles of the dailyx5 regimen. All regimens were dosed with a 28 day treatment cycle.
We have reported the clinical efficacy and safety results from the Phase 1 dose-escalation study in AML and MDS (Issa et al, Lancet Oncology 2015) and the Phase 2 randomized dose-response study in r/r AML at 2 doses (60 and 90 mg/m2) in a 5-day regimen (Kantarjian et al, ASH 2013) and 60 mg/m2 in the 10-day regimen (Griffiths et al, ASCO 2014).