News for 'YMI' - (YM BioSciences Posts Phase I/II Data for JAK Inhibitor CYT387 in Myelofibrosis at ASH 2012)
Dec 12, 2012 (Close-Up Media via COMTEX) -- YM BioSciences Inc. reported
updated results from the 166 patient Phase I/II study of its JAK1/JAK2
inhibitor, CYT387, for the treatment of myelofibrosis.
According to a release, 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 percent 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 percent at baseline to below 10 percent at week 40 of treatment.
-37 percent 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."
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 percent) discontinued the study, eight for possibly or probably
related adverse events, for an overall retention rate of 75 percent.
The majority of the 166 patients enrolled across the six study sites have
primary myelofibrosis (63 percent); 22 percent have post-polycythemia vera
myelofibrosis and 15 percent have post-essential thrombocythemia myelofibrosis.
Other patient characteristics include:
-DIPSS-Plus category: Int-1 - 10 percent; Int-2 - 62 percent; High - 28 percent
-RBC (Red blood cell) transfusion-dependent: 44 percent
-Palpable splenomegaly >10 cm: 79 percent
-Patients who had received previous therapies, including other JAK inhibitors
(13 percent) and IMiDs (9 percent).
Of the 68 evaluable patients who were transfusion dependent at baseline, 68
percent 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 percent
achieved at least a 50 percent reduction in transfusion requirement in any
3-month period.
The percentage of patients requiring transfusions decreased substantially during
the study, from 44 percent at baseline to below 10 percent at week 40 of
treatment.
Of the 28 evaluable patients who were transfusion dependent at baseline and
dosed at 300 mg QD, 75 percent have become transfusion independent for a minimum
of 12 weeks.
Three additional patients achieved a 12-week transfusion independence response
during the Extension Study.
Of the 145 patients evaluable for spleen response by palpation, 37 percent
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 percent of evaluable patients achieved more than a 50
percent maximal decrease in spleen size from baseline, with 87 percent achieving
more than a 25 percent maximal decrease.
Of the 51 patients who were evaluable for spleen response and dosed at 300 mg
QD, 39 percent 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 percent by MRI (defined as a 35 percent
decrease in spleen volume) and the median splenic decrease from baseline at six
months was -41 percent by volume measured by MRI.
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.
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.
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.
More information:
www.ymbiosciences.com
Harleyman!
