YM BioSciences Inc. has announced that updated interim anemia response data were reported for the first 60 patients enrolled in the Phase I/II trial of its JAK1/JAK2 inhibitor, CYT387, for the treatment of myelofibrosis.
The results were disclosed by Dr. Ayalew Tefferi (Mayo Clinic, Rochester, Minnesota), Chair of the Study, during the First Annual Florence Meeting on Myeloproliferative Neoplasms held in Florence, Italy on Saturday, April 16th, 2011.
"These results continue to highlight the potential for CYT387 to induce durable anemia responses, as demonstrated using these more rigorous measurement standards," said Dr. Nick Glover, President and CEO of YM BioSciences. "We look forward to reporting updated interim data on CYT387's safety and efficacy profile at the ASCO conference in June."
Dr. Tefferi reported that the overall anemia response rate was 58% in 33 transfusion-dependent patients. In this assessment, anemia response required a transfusion-free period of ≥12 weeks while on protocol drug therapy, with a minimum hemoglobin level of 8 g/dL.
The median duration of transfusion independence was reported to be 6 months (range 4-15 months). Only 2 (11%) of the 19 patients who achieved transfusion-independency were reported to require single episodes of PRBC transfusions.
The results were based on data observed for the first 60 patients enrolled in the dose escalation (n=21) and dose confirmation (n=39) portions of the 140 patient Phase I/II trial, for which recruitment has now been exceeded.
These 60 high/intermediate-risk myelofibrosis patients have received CTY387 orally once daily in 28-day cycles, and have completed a minimum of 3 cycles of treatment.