YM BioSciences Reports Phase I/II Data for JAK Inhibitor CYT387 at ASH 2012

YM BioSciences Inc. has reported updated results from the 166 patient Phase I/II study of its JAK1/JAK2 inhibitor, CYT387, for the treatment of myelofibrosis.

The results were presented this afternoon in an oral session at the 54th Annual Meeting of the American Society of Hematology underway in Atlanta, Georgia.

• 68% durable 12-week transfusion independence response rate with a maximal duration of response approaching three years and ongoing.
• The percentage of patients requiring transfusions decreased substantially, from 44% at baseline to below 10% at week 40 of treatment.
• 37% durable spleen response per IWG-MRT with a maximal duration of response of nearly 2.5 years and ongoing.
• The majority of subjects achieved a complete resolution or marked improvement of common constitutional symptoms.
• The majority of adverse events were Grade 1.

"These data continue to demonstrate that treatment with CYT387 results in significant, durable responses in transfusion dependency, splenomegaly and constitutional symptoms," said Dr. Nick Glover, President and CEO of YM BioSciences.

Dr. Glover continued, "The benefits CYT387 produces are highly encouraging for patients with myelofibrosis and underscore the clinical potential of this drug."