YM BioSciences expands CYT387 Phase I/II clinical trial for myelofibrosis in five sites

YM BioSciences Inc. (NYSE Amex: YMI, TSX: YM), today reported that the Phase I/II clinical trial for its orally available JAK1/JAK2 inhibitor, CYT387, in patients with myelofibrosis has been expanded to five sites. Of the additional sites, the Stanford Cancer Center (Stanford, California) under Principal Investigator Jason Gotlib, MD has already commenced enrolling patients.

YM also announced that the trial protocol has been extended to allow patients who have derived a clinical benefit to continue to receive treatment beyond the nine cycles of the core protocol. Subjects enrolled in the extension protocol will be evaluated every three months for up to 24 cycles of CYT387 treatment.

"The initiation of this trial at additional sites reflects the growing investigator interest for CYT387 and will help ensure the timely achievement of our enrolment targets. Receiving clearance to extend the protocol and allow patients to remain on CYT387 therapy further demonstrates the tolerability and durability of response our drug has produced so far," said Dr. Nick Glover, President and COO of YM BioSciences. "We anticipate this trial will be fully enrolled in the first calendar quarter of 2011 and that interim data from the fully-enrolled Phase II portion of the study will be available in mid-2011. We also look forward to the presentation of detailed results from the first 60 patients treated in the Phase I and early Phase II portion of this trial at the American Society of Hematology conference in early December 2010."

Furthermore, subject to regulatory approval, the trial will be expanded from 120 patients to 140 patients to include a 20-patient cohort to be dosed twice-daily at 150mg per dose. "Since we have seen encouraging efficacy signals at the 150 mg and 300 mg once daily dosing levels, it is clearly worthwhile to explore this additional dosing schedule," added Dr. Glover.

In addition to the Stanford Cancer Center, the Company anticipates patients will shortly be enrolled at the Royal Melbourne Hospital (Melbourne, Australia) under Principal Investigator Andrew Roberts, MD; at Princess Margaret Hospital (Toronto, Canada) under Principal Investigator Vikas Gupta, MD; and at the Jewish General Hospital (Montreal, Canada) under Principal Investigator Shireen Sirhan, MD. It is likely that additional clinical centers will join the program in the coming months.  The Phase I/II trial was initiated in November 2009 at Mayo Clinic (Rochester, Minnesota) under Principal Investigator Animesh Pardanani, MD with Ayalew Tefferi, MD as Chair.

"Early data for CYT387 has shown it is capable of reducing spleen size and controlling the constitutional symptoms of myelofibrosis and, importantly, may also provide the additional benefit of improving anemia in these patients. As there are no approved treatments in the United States for this disease, we welcome the opportunity to participate in the clinical development of a drug that could help these patients," said Dr. Jason Gotlib, Assistant Professor, Department of Medicine (Hematology), Stanford University Medical Center.

CYT387 was granted Orphan Drug Designation by the US FDA in September.