Novel formulations and vehicles

An oral pharmaceutical composition comprising an elongate hollow cylindrical capsule which is impermeable to gastric fluid and having a fill volume inside containing a weighting agent which is retained at one end of the fill volume, the capsule being buoyant and self-orientating in an aqueous fluid such that it floats in the aqueous fluid with its long axis perpendicular to the surface of the aqueous fluid,

• wherein the capsule is coated with a first inner sustained release layer comprising a diaminophenothiazine (DAPTZ) compound as active ingredient,
• and wherein the first layer is coated with a second outer layer not including an active ingredient,
• wherein the DAPTZ compound is selected from an oxidized methylthioninium (MT) compound or a leucomethylthioninium (LMT) compound or a combination thereof,
• wherein the first and second layers each comprise at least one hydrophilic polymer and at least one hydrophobic polymer, plus optionally one or more lubricants, gluidants or plasticisers.