(AP) Pfizer Inc. said Thursday it will pay $1.3 billion to Sanofi-Aventis Group to obtain full rights to the inhaled insulin the companies developed jointly. U.S. regulators are expected to rule upon the drug later this month.

Last September, a U.S. Food and Drug Administration panel voted to recommend inhaled insulin for approval but in October the agency said it wanted to extend its review of the medication, called Exhubera, by three months.

While there is a diabetes epidemic spreading across the country, some analysts had said doctors may be wary of prescribing Exhubera since the long-term effects of inhaling insulin won't be known for several years. Moreover, Merck & Co.'s withdrawal of its pain reliever Vioxx has caused doctors to become cautious of prescribing new drugs.

The agreement ends legal action Pfizer started against Sanofi-Aventis in 2004 after the company was created by a merger. Pfizer had originally been working with Aventis on the drug and said in a lawsuit that the merger constituted a change of control that violated the contract. A U.S. and a German court agreed with Pfizer last year and the two companies have been working on a resolution.

Pfizer will still pay an undisclosed royalty to Nektar Therapeutics, which makes the inhaling device and will also supply insulin.