US Patent 9693981 Zaleplon gastroretentive drug delivery system

A biodegradable, multi-layered controlled release gastroretentive dosage form which is optionally divided into a first dosage of zaleplon for controlled release and a second dosage of zaleplon for immediate release in the stomach and gastrointestinal tract of a patient, folded into a capsule which disintegrates upon contact with gastric juice and the gastroretentive dosage form unfolds rapidly upon contact with gastric juice. The biodegradable, multi-layered gastroretentive dosage forms of the invention provide efficient sleep induction with good sleep maintenance and minimal next day residual effects.