News for 'YMI' - (YM BioSciences Reports Phase I/II Data for JAK Inhibitor CYT387 in Myelofibrosis at ASH 2012)
MISSISSAUGA, ON, Dec. 9, 2012, 2012 (Canada NewsWire via COMTEX) -- - 68%
transfusion independence response rate and 37% durable spleen response rate -
YM BioSciences Inc. (NYSE MKT: YMI, TSX: YM) today 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 54(th) 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. "The benefits CYT387 produces are highly encouraging for patients
with myelofibrosis and underscore the clinical potential of this drug."
*International Working Group for Myelofibrosis Research and Treatment
Phase I/II Core Study Results
Study Design and Subject Disposition The Core Study consisted of nine 28-day
treatment cycles where CYT387 was orally self-administered, primarily at dosages
of 150 mg once-daily (QD), 300 mg QD or 150 mg twice-daily (BID). Patients who
tolerated and benefited from the drug could continue to receive CYT387 for an
indefinite period beyond the Core Study in an Extension Study. The 300 mg QD
dosing regimen has been selected for use in the anticipated Phase III clinical
development program.
The median follow-up time for patients in the Core Study and Extension Study is
16.9 months (range: 0.8 - 34.2 months; ongoing). During the Core Study, 42
patients (25%) discontinued the study, eight for possibly or probably related
adverse events, for an overall retention rate of 75%.
Subject Baseline Characteristics The majority of the 166 patients enrolled
across the six study sites have primary myelofibrosis (63%); 22% have
post-polycythemia vera myelofibrosis and 15% have post-essential thrombocythemia
myelofibrosis. Other patient characteristics include:
-- DIPSS-Plus category: Int-1 - 10%; Int-2 - 62%; High - 28%
-- RBC (Red blood cell) transfusion-dependent: 44%
-- Palpable splenomegaly >10 cm: 79%
-- Patients who had received previous therapies, including other
JAK inhibitors (13%) and IMiDs (9%).
Transfusion Independence Response Of the 68 evaluable patients who were
transfusion dependent at baseline, 68% became transfusion independent for a
minimum of 12 weeks during the Core Study. The median duration of the
transfusion-free period has not yet been reached (range: 85 - 988 days,
ongoing). Of the transfusion dependent patients who did not achieve a full
transfusion independence response, 23% achieved at least a 50% reduction in
transfusion requirement in any 3-month period.
The percentage of patients requiring transfusions decreased substantially during
the study, from 44% at baseline to below 10% at week 40 of treatment.
Of the 28 evaluable patients who were transfusion dependent at baseline and
dosed at 300 mg QD, 75% have become transfusion independent for a minimum of 12
weeks.
Three additional patients achieved a 12-week transfusion independence response
during the Extension Study.
Spleen Response Of the 145 patients evaluable for spleen response by palpation,
37% achieved a response per IWG-MRT. The median duration of spleen response
reported was 744 days (range: 56 - 859 days, ongoing). Three additional subjects
achieved spleen response during the Extension Study.
During the Core Study, 50% of evaluable patients achieved more than a 50%
maximal decrease in spleen size from baseline, with 87% achieving more than a
25% maximal decrease.
Of the 51 patients who were evaluable for spleen response and dosed at 300 mg
QD, 39% achieved a response per IWG-MRT.
In the Core Study, 11 patients were evaluable for spleen response by MRI. The
response rate at six months was 45% by MRI (defined as a 35% decrease in spleen
volume) and the median splenic decrease from baseline at six months was -41% by
volume measured by MRI.
Constitutional Symptoms Response The majority of patients reporting
constitutional symptoms at baseline demonstrated a Complete Resolution or Marked
Improvement of their symptoms, including night sweats, pruritus and bone pain.
Safety Results CYT387 is well tolerated in myelofibrosis patients for dosing
periods currently up to three years and ongoing. The majority of adverse events
were Grade 1. Common reported adverse effects include thrombocytopenia;
transient, mild dizziness; mild peripheral neuropathy; and abnormalities in
liver/pancreas-related laboratory tests. Treatment-emergent anemia and
neutropenia were rarely observed.
Oral presentation and YM conference call: The results from the Phase I/II study
are being presented today at 5:15pm ET in an Oral Session at the 2012 Annual
Meeting of the American Society of Hematology in Atlanta, Georgia. YM will also
host a webcast meeting open to members of the investment community to discuss
the results. This event will be held from 6:30-7:30am ET on Monday, December
10(th) in the Imperial Salon Room A of the Atlanta Marriott Marquis, 265
Peachtree Center Ave. NE, Atlanta, Georgia. Access to the webcast will be
available from YM's website at www.ymbiosciences.com or at www.newswire.ca.
About CYT387: CYT387 is an inhibitor of the kinase enzymes JAK1 and JAK2, which
have been implicated in a family of hematological conditions known as
myeloproliferative neoplasms, including myelofibrosis, and as well in numerous
other disorders including indications in hematology, oncology and inflammatory
diseases. Myelofibrosis is a chronic debilitating disease in which a patient's
bone marrow is replaced by scar tissue and for which treatment options are
limited or unsatisfactory. Both the U.S. Food and Drug Administration (FDA) and
the European Commission have designated CYT387 an Orphan Drug for the treatment
of myelofibrosis.
AboutYM BioSciences YM BioSciences Inc. is a drug development company primarily
focused on advancing CYT387, an orally administered inhibitor of both the JAK1
and JAK2 kinases, which have been implicated in a number of hematological and
immune cell disorders including myeloproliferative neoplasms and inflammatory
diseases as well as certain cancers. Positive interim results have been reported
from a Phase I/II trial of CYT387 in 166 patients with myelofibrosis. YM's
portfolio also includes several preclinical programs underway with candidates
from its library of novel compounds identified through internal research
conducted at YM BioSciences Australia.
Harleyman!
