AstraZeneca receives six months pediatric exclusivity patent extension for ARIMIDEX (anastrozole)

Dec 2 2007

AstraZeneca has announced that the United States (US) Food and Drug Administration (FDA) has granted an additional six-month period of exclusivity to market ARIMIDEX (anastrozole) for its licensed breast cancer indications until June 2010.

Prior to pediatric exclusivity being granted by the FDA, the patent was due to expire in December 2009.

ARIMIDEX is currently approved in the US for the for the following indications:

• The adjuvant treatment (treatment following surgery with or without radiation) of postmenopausal women with hormone receptor positive early breast cancer (Sub Part H approval granted in 2002, final approval in 2005).
• The first-line treatment of postmenopausal women with hormone receptor positive or hormone receptor unknown locally advanced or metastatic breast cancer (granted in 2000).
• The treatment of advanced breast cancer in postmenopausal women with disease progression following tamoxifen therapy. Patients with hormone receptor-negative disease and patients who did not previously respond to tamoxifen therapy rarely responded to ARIMIDEX (granted in 1995).

Dr. John Patterson, Executive Director of Development at AstraZeneca said "Pre-clinical and clinical data supported the investigation of the therapeutic potential of ARIMIDEX in pediatric conditions that manifest symptoms resulting from increased estrogen production, for example: gynecomastia in pubertal boys and precocious puberty in girls with McCune-Albright Syndrome (MAS). While pleased to have been able to work with the FDA in investigating the potential benefits of ARIMIDEX in these settings, AstraZeneca will not be seeking an indication in either of these pediatric conditions based on trial results."

In the US, ARIMIDEX sales reached $507 million for the nine months of 2007. ARIMIDEX has a market leading 38.3 percent share of total prescriptions for hormonal treatments for breast cancer. Sales for the nine months were up 15 percent, with total prescriptions 6 percent higher than last year.