Eribulin Mesylate Demonstrated Anti-Tumor Activity in Heavily Pretreated Patients...

Eribulin Mesylate Demonstrated Anti-Tumor Activity in Heavily Pretreated
Patients with Advanced Breast Cancer
Phase II Data Presented at ASCO Showed Acceptable Tolerability Profile, with
Low Incidence of Grade 3 and 4 Neuropathy

WOODCLIFF LAKE, N.J., May 15 /PRNewswire/ -- The investigational
chemotherapeutic agent eribulin mesylate (E7389) demonstrated activity in a
heavily pretreated population of women with locally advanced or metastatic
breast cancer, according to results of a multi-center Phase II clinical trial.
The study also suggests that eribulin mesylate has a manageable tolerability
profile, with a low incidence of Grade 3 (severe) and no Grade 4 (disabling or
life-threatening) neuropathy. These data (abstract #1084) will be presented
at the 44th Annual Meeting of the American Society of Clinical Oncology (ASCO)
on Monday, June 2 from 2 to 6 p.m. at S Hall A1 of McCormick Place.
"The anti-tumor activity of eribulin mesylate, as observed in this study,
is encouraging, given the limited treatment options for women with advanced
breast cancer who have previously received multiple lines of therapy," said
lead investigator Linda T. Vahdat, MD, of Weill Cornell Medical College in New
York. "The subjects in this trial had received a median of four prior
chemotherapy regimens that included an anthracycline, a taxane and
capecitabine."
About Study 211
Study 211 is a Phase II, open-label, single-arm study evaluating the
efficacy and safety of eribulin mesylate in patients with locally advanced or
metastatic breast cancer who had received an anthracycline, a taxane and
capecitabine as prior therapy, and who were refractory to their last
chemotherapy regimen, as documented by progression on or within six months of
that therapy.
Of 299 patients enrolled in the study, 291 were treated with eribulin
mesylate. The median age of those patients was 56 years (range: 26-80 years).
Eribulin mesylate was administered at a dose of 1.4mg/m2 as a 2- to 5-minute
intravenous infusion on Days 1 and 8 of a 21-day cycle. Patients received a
median of four cycles of eribulin mesylate (range 1-27). No premedication to
prevent hypersensitivity was required.
Two-hundred sixty-nine patients met the key inclusion criteria. In
patients who received a median of four cycles of eribulin mesylate, Overall
Response Rate (ORR) by Independent Review (IR) was 9.3% (all Partial Responses
(PR); 95% confidence interval [CI]: 6.1%-13.4%). Investigator-assessed ORR
was 14.1% (1 CR; 95% CI: 10.2%-18.9%). Nearly half (46.5%) the patients had
stable disease (SD) after treatment with eribulin mesylate. The clinical
benefit rate (CBR, defined as CR+PR+SD greater than or equal to 6 months) was
17.1% (95% CI: 12.8%-22.1%).
The median duration of response was 4.2 months (126 days, range: 42*-258
days; 95% CI: 86-147). Median progression-free survival (PFS) was 2.6 months
(79 days, range: 1*-397 days), and the median overall survival (OS) rate was
10.3 months (315 days, range: 19-604 days; 95% CI: 279-350). The six-month
PFS and OS rates were 16.0% (95% CI: 8.6-17.0) and 72.3%, respectively (95%
CI: 66.9-77.6).
The safety analysis included all 291 patients who received treatment with
eribulin mesylate. Patients with up to Grade 2 peripheral neuropathy were
included in the study. The most frequently reported Grade 3 (severe) or Grade
4 (disabling or life-threatening) adverse events were neutropenia (a decrease
in the number of granular white blood cells, 54%); febrile neutropenia, 5.5%,
leukopenia (low white blood cell count, 14%), and weakness/fatigue (10%; no
Grade 4 events). Grade 3 peripheral neuropathy (a functional disturbance or
damage to nerves outside the brain and spinal cord) was reported in 5.5% of
patients. No Grade 4 peripheral neuropathy events were reported. No
correlation was seen between Grade 2 peripheral neuropathy and deterioration.
"In this study, eribulin mesylate appeared to have an acceptable
tolerability profile, particularly with regard to the low incidence of
peripheral neuropathy," noted Vahdat. "None of the reported cases of
neuropathy were disabling, suggesting that eribulin mesylate, if approved, may
be a useful addition to the treatment armamentarium for advanced breast
cancer."
About Eribulin Mesylate
Eribulin mesylate is being developed by Eisai as a potential new
chemotherapeutic agent. It suppresses the growth of microtubules, which are
involved in various cellular processes in the body, such as cell division.
Eribulin mesylate is a synthetic analog of halichondrin B, a naturally
occurring compound which was first isolated from a marine sponge Halichondria
okadai in 1992.
About Eisai Corporation of North America
Eisai Corporation of North America is a wholly-owned subsidiary of Eisai
Co., Ltd., a research-based human health care (hhc) company that discovers,
develops and markets products throughout the world. Eisai focuses its efforts
in three therapeutic areas: neurology, gastrointestinal disorders and
oncology/critical care.
Eisai Corporation of North America supports the activities of its
operating companies in North America, which include: Eisai Research Institute
of Boston, Inc., a discovery operation with strong organic chemistry
capabilities; Morphotek, Inc., a biopharmaceutical company specializing in the
development of therapeutic monoclonal antibodies; Eisai Medical Research Inc.,
a clinical development group; Eisai Inc., a commercial operation with
manufacturing and marketing/sales functions; MGI PHARMA, INC., an R&D and
commercial operation with manufacturing and marketing/sales functions; and
Eisai Machinery U.S.A., which markets and maintains pharmaceutical
manufacturing machinery.
(*) Censored observation.
SOURCE Eisai Corporation of North America

Judee Shuler, Eisai Corporation of North America, During ASCO,
+1-908-337-2540, Office, +1-201-746-2241