Asia PR News

BERNE, Dec. 28 /PRNewswire-AsiaNet/ –

- Letrozole Helps Prevent Cancer from Spreading to Other Parts of the Body -
- Women at Highest Risk for Recurrence Gain Most From Taking Letrozole -

According to newly published data, postmenopausal women with
hormone-sensitive early breast cancer receiving letrozole following surgery
(adjuvant use) have a significantly greater chance of avoiding a recurrence
than do women receiving tamoxifen. Letrozole is especially effective at
preventing the disease from spreading to another part of their body (distant
metastases). Women whose breast cancer returns or spreads to a distant site are
known to be much more likely to die from their disease. These data, which
appear in the December 29, 2005 issue of the New England Journal of Medicine,
are the first published results of the landmark BIG 1-98 study.

In the study, women at higher risk for recurrence benefited most from
letrozole. These patients included women whose disease had spread to the lymph
nodes at initial diagnosis and those who had prior adjuvant chemotherapy.

Quote
"The publication of these findings in a journal as influential as the New
England Journal of Medicine is likely to have a significant impact on the way
postmenopausal women with hormone sensitive early breast cancer are treated
after surgery," said Professor Beat Thuerlimann, St. Gallen, Switzerland, BIG
1-98 Trial Study Chair. "We are especially encouraged by the substantial
benefit seen in women at high risk for recurrence, which may ultimately lead
to improved survival and outcomes in this group."

Compared with tamoxifen, letrozole significantly reduced the risk of:

* breast cancer recurrence, the appearance of another breast tumor or
other malignancy or death by 19 percent (p=0.003)

* distant metastases by 27 percent (p=0.001)

* recurrence in women whose disease had already spread to their lymph
nodes by 29 percent (node positive disease) (p=<0.001)

* recurrence in women who had prior chemotherapy by 30 percent (p=0.01).

Methods and Additional Results
BIG 1-98 is a multinational phase III double-blind, randomized
multi-center trial being conducted in 27 countries. The study involves more
than 8,000 postmenopausal women with early breast cancer who have hormone
receptor-positive tumors. It is the only clinical trial designed to directly
compare letrozole and tamoxifen as well as a sequencing of both agents during
the first five years following breast cancer surgery.

A primary goal of the study is to determine if letrozole can reduce the
risk of breast cancer recurrence compared with tamoxifen, as measured by
disease-free survival (DFS). A DFS event was defined as a local, regional or
distant breast cancer relapse, occurrence of a second [non-breast] malignancy
or death prior to cancer event. The newly published results document the
effect on recurrence of initial treatment with tamoxifen versus initial
treatment with letrozole. Median follow-up was 26 months (half of the patients
had been on study for 26 months or more), with more than 1100 of those
patients having completed five years of therapy. The results assessing the
role of sequencing are expected in 2008.

Results further demonstrate that among the 4,003 patients in the letrozole
group and 4,007 patients in the tamoxifen group:

* 10.2 percent of the letrozole participants and 13.6 percent of the
tamoxifen participants are projected to experience a breast cancer
recurrence through five years

* Overall survival favored letrozole, but the difference was not
statistically significant

* Letrozole led to a similar risk reduction in all participants with
estrogen receptor positive status, regardless of progesterone
receptor status

Additionally, letrozole and tamoxifen exhibited different safety profiles.

— More common on tamoxifen were:

* venous thrombosis and embolism (clots)
* vaginal bleeding
* endometrial abnormalities (changes in the lining of the womb)

— More common on letrozole were:
* bone fractures
* joint pain

Invasive endometrial cancers were more frequent on tamoxifen (0.1% vs.
0.3%, L vs. T), while cardiac events (life-threatening or fatal) were more
common on letrozole (0.8% vs. 0.4%, L vs. T), but both of these events were
rare.

The study is being conducted under the umbrella of the Breast
International Group (BIG), and is coordinated and managed by the International
Breast Cancer Study Group (IBSCG). The IBSCG is an active member of the BIG
organization. Novartis, the producer and distributor of letrozole (Femara(R))
gave financial support.

About Early Breast Cancer
Early breast cancer (EBC) is defined as cancer that is localized to breast
tissue and/or nearby lymph nodes. Worldwide, about 800,000 women are diagnosed
with EBC each year. Primary therapy for EBC usually involves surgery to remove
the tumor and surrounding tissue. Standard post-surgery therapy (adjuvant)
typically includes radiation and/or chemotherapy. If the tumor is
hormone-receptor positive, women then receive endocrine treatment with five
years of tamoxifen, which was for decades the standard of care for
postmenopausal women until aromatase inhibitors such as letrozole offered
further potential benefits.

About The International Breast Cancer Study Group
The International Breast Cancer Study Group (IBSCG) is a non-profit
organization founded (as the "Ludwig Breast Cancer Study Group") in 1977. It
is a cooperative group that has conducted numerous high quality and important
clinical trials of adjuvant therapy for patients with operable breast cancer
over 27 years. The IBCSG is headquartered in Berne as a foundation under Swiss
law. With its network of investigators spanning five continents, the IBCSG has
always been dedicated to innovative clinical research designed to improve the
outcome of women with breast cancer.

About The Breast International Group
The BIG is an international non-profit organization established under
Belgian law. As a communications network rather than a clinical research group
in the traditional sense, BIG brings its members — cooperative groups based
in Europe, Australasia, Latin America and Canada that have affiliated centers
around the world — together in an organized way to collaborate in the design,
conduct and interpretation of clinical trials in EBC.

Additional information regarding BIG 1-98 and IBCSG can be found on the
Web site www.ibcsg.org.

Contact persons:
Prof. Beat Thuerlimann
BIG 1-98 Study Chair
Phone: +41.71.494.20.65
Email: beat.thuerlimann@kssg.ch

Nadia Munarini, PhD
IBCSG Head of Communication
Phone: +41.31.389.92.27
Mobile: +41.79.207.45.82
Email: nadia.munarini@ibcsg.org

Dana Kahn Cooper
Cooper Communications, Inc
Phone: +1.732.817.1800
Fax: +1.732.817.1834

SOURCE: The International Breast Cancer Study Group

CONTACT:

Prof. Beat Thuerlimann,
BIG 1-98 Study Chair,
+41-71-494-20-65,
or beat.thuerlimann@kssg.ch ;

or Nadia Munarini, PhD,
IBCSG Head of Communication,
Phone: +41-31-389-92-27,
or Mobile: +41-79-207-45-82,
or nadia.munarini@ibcsg.org ;

or Dana Kahn Cooper
of Cooper Communications, Inc,
Phone: +1-732-817-1800,
or Fax: +1-732-817-1834

Web site: http://www.ibcsg.org