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On Wednesday, Pfizer announced a global partnership with a German drug firm to jointly market Spiriva, an experimental drug to treat emphysema and other chronic respiratory diseases.

Annual U.S. sales for Spiriva could reach more than $1 billion, giving Pfizer another potential blockbuster drug for its already strong portfolio.

Pfizer's partner in the new venture is

Boehringer Ingelheim

, a privately held German drug maker that discovered and developed Spiriva. The drug treats chronic obstructive pulmonary disease, or COPD, the term for a number of respiratory disorders that limit the sufferer's airflow and eventually restrict normal physical activity.

Smoking is the most common cause of COPD, which includes emphysema and chronic bronchitis. The disease afflicts 600 million people worldwide according to Pfizer, and is the fourth-leading cause of death in the U.S. after heart attacks, cancer and stroke.

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Boehringer Ingelheim is already working with European drug regulators to gain approval for Spiriva as early as the middle of 2002. A filing for U.S. sales could come later this year, with approval in late 2002.

"Spiriva could become the new gold standard for the symptomatic treatment of COPD," says Mark Striker, research analyst for

Salomon Smith Barney

, in a research note. Potential U.S. annual sales of Spiriva could reach $1.1 billion, says Striker, who rates Pfizer a buy. His firm does banking business with Pfizer.

Pfizer, the nation's largest drug firm, already has one of the strongest portfolios of current and experimental drugs. The company is gearing up to launch sales of Geodon, a new antipsychotic drug, while sales of cholesterol drug Lipitor are forecast to jump 26% to $6.3 billion in 2001.

Boehringer Ingelheim already sells two drugs to combat COPD, which combined accounted for $970 million in sales in 1999. Spiriva is reportedly more effective than these two drugs, and is easier to use because patients only have to take it once a day, instead of four times a day.

Under terms of today's agreement, Boehringer Ingelheim and Pfizer will conduct additional clinical trials of Spiriva and share global marketing rights. Financial terms of the deal were not disclosed.

Pfizer closed down $1, or more than 2%, to $40 in Wednesday trading.

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