Aegerion Pharmaceuticals Inc. (Nasdaq: AEGR) is buying Myalept, a medication, from AstraZeneca (NYSE: AZN) for $325 million.

Myalept is an injectable product that can be used for treatment in patients with lipodystrophy, which causes the loss of fat from under the skin. The lack of leptin, the cause of lipodystrophy, can lead to diabetes and other diseases. The product has approval from the U.S. Food & Drug Administration. The deal is expected to close in January.

Cambridge, Massachusetts-based Aegerion is a biopharmaceutical company that develops medications for patients with debilitating rare diseases.

AstraZeneca, headquartered in London, agreed to the sale after the company fended off takeover efforts from Pfizer (NYSE: PFE) for much of 2014.

Other recent pharmaceutical deals include Warburg Pincus' $92 million investment in drug ingredient maker Laurus Labs Private Ltd. and Capicor Therapeutics Inc.'s deal for heart-failure drug rights from Meditronic Inc. (NYSE: MDT).