YM BIOSCIENCES REPORTS PHASE II DATA FOR NIMOTUZUMAB

    YM BIOSCIENCES REPORTS PHASE II DATA FOR NIMOTUZUMAB IN METASTATIC COLORECTAL
CANCER

    - Overall Survival And Disease Control Outcomes, Coupled With Low
    Toxicity, Support The Continued Development Of The EGFR Antibody In
    Patients With Colorectal Cancer -

    - Conference Call To Discuss Results On Aug. 5 At 12:00PM EDT -

    MISSISSAUGA, ON, Aug. 4 /CNW/ - YM BioSciences Inc. (AMEX: YMI, TSX: YM,
AIM: YMBA), an oncology company that identifies, develops and commercializes
differentiated products for patients worldwide, today announced preliminary
results obtained from its open-label, Phase II study (YMB1000-015) of
nimotuzumab in patients with irinotecan-refractory, metastatic colorectal
cancer (mCRC). The data are based on 58 evaluable patients of the 61 enrolled
in the trial. The trial was conducted at 10 centres across Canada and
consisted of treatment with 400 mg of nimotuzumab weekly plus irinotecan in
patients refractory to irinotecan alone, with patients remaining on
nimotuzumab until disease progression.
    "These preliminary data are released upon our being advised that the
trial has now reached the point at which more than 50% of the patients have
died. The overall survival (OS) and disease control rate (DCR) for patients
receiving nimotuzumab compare well with published results in similar patient
populations treated with cetuximab, a currently marketed EGFR monoclonal
antibody. Nimotuzumab also continues to display a safety profile unequalled in
its class. This low incidence of toxicity with nimotuzumab may be related to
differences reported in its interaction with EGF receptors compared with other
EGFR targeting antibodies," said Dr. Paul Keane, Director of Medical Affairs
for YM BioSciences.
    The prospective primary endpoint of YMB1000-015 is objective tumour
response rate (RR) with secondary endpoints that include overall survival, the
rate and duration of stable disease, and progression free survival (PFS). The
RR was 3.4% while the disease control rate reported was 50%, consisting of
27 patients with stable disease and two patients with partial response as
determined using RECIST criteria. Median PFS was 12 weeks. Overall survival
(Kaplan-Meier) in the evaluable patients was 9.3 months.
    "The median overall survival of 9.3 months and disease control rate of
50% together with the exceptional safety profile of nimotuzumab support
continuing development of nimotuzumab in patients with colorectal cancer,"
noted Dr. Amil Shah, medical oncologist and Chair, Gastrointestinal Tumor
Group at the BC Cancer Agency and Principal Investigator for the trial.
    Tissue samples from 17 patients were available for kRas analysis.
Approximately 30% of the patients had mutated kRAS. PFS of 12 weeks was
observed in patients with the mutation and 18 weeks in patients with wild
type. Although only a relatively small number of samples were analyzed these
results are in line with expectations.
    In the following table, the nimotuzumab/irinotecan (N-Mab + Iri) data are
shown against results obtained from an integrated analysis of four trials of
patients treated with cetuximab/irinotecan (C-Mab + Iri) following irinotecan
failure in a similar patient population (J Clin Oncol 26: 2008 May 20 suppl;
abstract 4062). That abstract describes that disease control rates in the
total of 1,567 patients ranged from 45% to 56% and the median overall survival
of the patients ranged from 8.6 to 9.5 months. The reported OS and DCR in
YMB1000-015 are similar to those observed in the other trials, including
BOND 1, however in YMB1000-015 they are accompanied by an important advantage
in the toxicity profile of nimotuzumab.

    -------------------------------------------------------------------------
                 Studies in mCRC with EGFR-targeting MAbs in
                       irinotecan-refractory patients
    -------------------------------------------------------------------------
                      BOND I       MABEL       LABEL       ELSIE  YMB1000-015
                      (C-MAb      (C-MAb      (C-MAb      (C-MAb      (N-MAb
                       + Iri)      + Iri)      + Iri)      + Iri)      + Iri)

    N                    218       1,147          79         123          58

    Response Rate (%)   22.9        20.1        26.6        13.8         3.4

    Disease Control
     Rate (%)           55.5        45.2        55.7        49.6        50.0

    Median PFS (w)        18        14.1        17.4        12.1          12
     (95%CI)        (12-18.9)   (13-17.1) (11.7-18.9)  (9.7-17.7)       (N/A)

    Median Overall
     Survival (m)        8.6         9.2         9.2         9.5         9.3
     (95%CI)        (7.6-9.6)   (8.6-9.8)  (7.9-10.8)  (7.1-11.7)   (5.5-inf)
    -------------------------------------------------------------------------
    Sources: (JCO, 26: 2008, May 20, suppl:4062/YM BioSciences)


    Nimotuzumab was administered without premedication, and, in contrast to
cetuximab, no infusion reactions were observed. No subjects discontinued
treatment or required dose reductions due to nimotuzumab-related adverse
events. Only 22% of patients (15) were reported with rash, all of which was
graded I/II. In contrast, Grade I/II rash was reported in 80% and Grade III/IV
in 9.4% of patients in the cetuximab/irinotecan trial known as BOND 1.
Neutropenia (4% vs. 9.4%), asthenia (5.2% vs. 13.9%) and diarrhea (7% vs.
21.2%) were lower in the nimotuzumab trial than in BOND 1. Two patients had
Grade I hypomagnesemia, a condition affecting approximately 50% of patients
treated with cetuximab.
    "The results support further development of nimotuzumab in this setting
and trials in metastatic colorectal cancer are high on the list of indications
that YM and its licensees plan to develop. Initially, however, YM will
concentrate on those indications where nimotuzumab can complete pivotal trials
in the shortest time within its available resources. We intend to file for
registration trials in 2008 for patients with non small cell lung cancer
(NSCLC) and for those with brain metastases because of compelling observations
in Phase II trials in those indications and because they require shorter
development times than colorectal trials would require," said David Allan,
Chairman and CEO of YM BioSciences.

    Notice of conference call

    YM BioSciences will hold a conference call at 12:00pm EDT tomorrow,
August 5, where members of the professional investment community are invited
to discuss the results with management. A live audio webcast of the conference
call will be available at www.ymbiosciences.com. Dial-in numbers for the call
will be provided on YM's website and by press release notice tomorrow morning.

    About nimotuzumab

    Nimotuzumab is a humanized monoclonal antibody that targets the epidermal
growth factor receptor. In clinical trials and commercial sales of nimotuzumab
involving approximately 3,000 patients worldwide nimotuzumab has been observed
to have a significantly improved side-effect profile compared to other
EGFR-targeting drugs while demonstrating clinical benefit. No case of Grade
3-4 rash has been reported for nimotuzumab and reports of any of the other
side effects that are typical of EGFR-targeting molecules have been rare.
    The drug is being developed by CIMYM Biosciences Inc, a majority-owned
subsidiary of YM, and by CIMYM's licensees, that include Daiichi Sankyo in
Japan, Oncoscience AG in Europe, Innogene Kalbiotech in Singapore/Indonesia
and Kuhnil in Korea, each of whom have a well-established, focused and
advanced development program underway for this highly differentiated
EGFR-targeting molecule.
    Prolonged survival in heavily pretreated patients who had disease control
from treatment with nimotuzumab following disease progression has been
previously observed and most recently reported in patients with various solid
tumors receiving nimotuzumab monotherapy (Proc. ASCO Abstract No. 14030, 2007)
and in patients with Stages III and IV NSCLC unsuitable for chemotherapy,
treated with palliative radiation and nimotuzumab (Proc. ASCO Abstract
No. 3037, 2008).
    Nimotuzumab is currently being evaluated in two Phase III trials as a
first-line treatment for pediatric pontine glioma and adult glioma, a
Phase II/III trial as a treatment for pancreatic cancer and the phase II study
in colorectal cancer reported on in this release. In addition the drug has
been approved for marketing in eight countries and is currently under review
for marketing approval by EMEA.

    About YM BioSciences

    YM BioSciences Inc. is an oncology company that identifies, develops and
commercializes differentiated products for patients worldwide. In addition to
nimotuzumab, the Company is developing AeroLEF(TM), a proprietary,
inhaled-delivery composition of free and liposome-encapsulated fentanyl in
development for the treatment of moderate to severe pain, including cancer
pain.

    This press release may contain forward-looking statements, which reflect
the Company's current expectation regarding future events. These
forward-looking statements involve risks and uncertainties that may cause
actual results, events or developments to be materially different from any
future results, events or developments expressed or implied by such
forward-looking statements. Such factors include, but are not limited to,
changing market conditions, the successful and timely completion of clinical
studies, the establishment of corporate alliances, the impact of competitive
products and pricing, new product development, uncertainties related to the
regulatory approval process and other risks detailed from time to time in the
Company's ongoing quarterly and annual reporting. Certain of the assumptions
made in preparing forward-looking statements include but are not limited to
the following: that nimotuzumab will continue to demonstrate a competitive
safety profile in ongoing and future clinical trials; that AeroLEF(TM) will
continue to generate positive efficacy and safety data in future clinical
trials; and that YM and its various partners will complete their respective
clinical trials within the timelines communicated in this release. We
undertake no obligation to publicly update or revise any forward-looking
statements, whether as a result of new information, future events or
otherwise.



For further information: James Smith, the Equicom Group Inc., Tel. (416)
815-0700 x 229, Email: jsmith(at)equicomgroup.com; Thomas Fechtner, the Trout
Group LLC, Tel. [phone], Email: tfechtner(at)troutgroup.com; Nominated
Adviser, Canaccord Adams Limited, Ryan Gaffney, Tel. [phone]
(YM. YMI  YMBA)


 



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