King Pharmaceuticals, Inc. announced the commencement of the Phase II clinical trial programme for the development of an extended release formulation of Sonata (zaleplon), a nonbenzodiazepine treatment for insomnia. The Phase II clinical trial programme is designed to select the most effective extended release formulation of Sonata utilizing Elan Corporation's commercially proven Spheroidal Oral Drug Absorption System (SODAS) as the drug delivery technology.

Jefferson Gregory, CEO of King, stated, "We are pleased to announce the initial dosing of the first patients in the Phase II clinical trial programme for the development of an extended release formulation of Sonata." Gregory added, "With US patent coverage that extends to 2018, the extended release formulation should establish Sonata as a long-term cornerstone product for our company. Moreover, this development programme should provide us with the opportunity to procure additional patents potentially covering, among other things, unique biopharmaceutical characteristics and methods-of-use related to the extended release formulation of Sonata."

The prescription insomnia market equaled approximately $2.0 billion in the US during 2003 and is expected to grow to over $3.5 billion by 2008.

Michael Jolly, executive vice president, R&D, of King, commented, "The goal of the Phase II clinical trial programme is to determine which new formulation is the most efficacious for the purpose of increasing total sleep time and reducing any potential for premature awakenings, while continuing to build upon the quick onset profile currently available in the immediate release formulation of Sonata."