Abstract: A composition comprising a polypeptide and an active agent covalently attached to the polypeptide. Also provided is a method for delivery of an active agent to a patient comprising administering to the patient a composition comprising a polypeptide and an active agent covalently attached to the polypeptide. Also provided is a method for protecting an active agent from degradation comprising covalently attaching the active agent to a polypeptide. Also provided is a method for controlling release of an active agent from a composition comprising covalently attaching the active agent to the polypeptide.
Type:
Grant
Filed:
August 22, 2000
Date of Patent:
April 6, 2004
Assignee:
New River Pharmaceuticals Inc.
Inventors:
Thomas Piccariello, Lawrence P. Olon, Randall J. Kirk
Abstract: An embodiment of the present invention comprises a multi-level PWM inverter that is constructed by cascading multi-level H-bridge inverters and providing different voltage inputs to the multi-level H-bridges. The values of the voltages, or the ratios of the voltages, are selected in order to provide an increased number of output levels. In the cascaded arrangement, at least one of the multi-level H-bridge inverters has more than three levels. Preferably, at least one of the multi-level H-bridge inverters is a 5-level inverter. According to one aspect of the invention, the cascaded arrangement may use a primary 5-level H-bridge with at least one 3-level H-bridge (referred to as a “5/3H” arrangement). This arrangement can provide up to fifteen output levels if regenerative voltage sources are used, and up to eleven output levels if a non-regenerative voltage sources are used.