Under the drugmaker's new program, patients with a prescription can pay $40 a month for Arimidex to be mailed to their homes.

That is less than patients would generally pay for the brand, but is typically more than the co-payment for generic versions of the drug, also known as anastrozole.

AstraZeneca said it started the program in response to patients asking for options to buy the brand, which are prohibitively more expensive compared with generics since the cheaper copies became available in mid-2010.

"We definitely got lots of calls every month to our information center on how they could get a branded option," said Steve Davis, Astra's executive director overseeing its mature brands in the United States. "There are patients that prefer not to be on the generic option."

Health plans generally try to steer patients to generic versions once they become available because they are significantly less expensive.

AstraZeneca's move is similar to one by Pfizer Inc, which has offered delivery of brand versions of its Lipitor drug to patients after the big-selling cholesterol treatment lost U.S. patent protection in November.

Arimidex was once a big seller for Astra. In 2009, the last full year before generics arrived, Arimidex sales reached $1.9 billion globally and about $880 million in the United States alone. Last year, Astra's U.S. sales of the drug fell 91 percent to $42 million, reflecting the toll taken by generic rivals.

In Arimidex's class of drugs, known as aromatase inhibitors, some 96 percent of prescriptions are generic, Davis said.

A major wrinkle in the Arimidex Direct program is that patients do not use their health insurance to get their pills, but pay out of pocket. AstraZeneca is contracting with Express Scripts Inc, a pharmacy benefit management company that mails the prescription to patients.

At $40 a month, the price is more than the usual $10 co-pay for generics, but less than insured patients would otherwise pay for the brand, which may only be available at close to the full price, according to Express Scripts.

Drugstore.com lists a one-month supply of Arimidex at $458.97 and anastrozole at $186.01.

"Given the seriousness of the condition, there may be individuals who are willing to pay $40 for the brand," said Everett Neville, chief trade relations officer Express Scripts. "That's completely different than you might see with some less emotionally charged conditions."

Aromatase inhibitors are used to treat breast cancer or help keep breast cancer from recurring after surgery, according to the American Cancer Society.

Davis said AstraZeneca started the program late last year, initially marketing it through brochures left in oncologists' offices and wanted to make sure it was working smoothly before publicizing it. About 300 patients are enrolled so far.

"This is a very emotional disease and it brings a lot of patient concerns," Davis added. "There is brand loyalty."

(Reporting By Lewis Krauskopf; editing by Andre Grenon)

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