Modified release drug powder composition comprising gastro-retentive raft forming systems having trigger pulse drug release

An orally administrable drug powder composition which forms a gastro-retentive RAFT having at least two trigger pulses, the composition comprising:

• (a) at least one drug in a first pulse release form which releases in less than about 3 hours, wherein the drug is a free base or acid active pharmaceutical ingredient, or a pharmaceutically acceptable salt, solvate or hydrate, thereof;
• (b) at least one drug in a trigger release form which is the second pulse release form comprises swelling delayed trigger system, wherein the swelling delayed trigger system comprises granules comprising at least one pH-independent, water insoluble, water-permeable diffusion barrier coating, the drug, a gelling agent, a swelling enhancer, wherein the at least one water permeable diffusion barrier coating is in a coating layer, over the at least one drug, the gelling agent, the swelling enhancer and excipients in the granules, wherein the drug is a free base or acid active pharmaceutical ingredient, or a pharmaceutically acceptable salt, solvate or hydrate, thereof;
• (c) a RAFT system comprising at least one crosslinkable polysaccharide or at least two ionic crosslinkable anionic polymers, at least one ionic crosslinking agent, and at least one non-toxic gas generating agent which reacts with acid in the stomach to generate a non-toxic gas;
• and
• wherein following oral ingestion, the composition provides a self-assembling gastro-retentive RAFT having entrapped therein, the at least one drug in the first pulse system of (a), the at least one drug in the second pulse system of (b), and the gas generated in situ by the non-toxic gas generating agent, thereby providing a floating gastro-retentive RAFT having the first pulse system and the second pulse system which retains at least the drug in the second pulse release form in the stomach for at least about 3 hours,
• provided that the composition does not include a gamma hydroxybutyrate, or a gamma hydroxybutyrate salt, hydrate, tautomer, or solvate, or complex thereof.