| abstract |
Drug delivery devices that are orally administered, and that release active ingredients in the colon, are disclosed. In one embodiment, the active ingredients are those that inactivate antibiotics, such as macrolides, quinolones and beta-lactam containing antibiotics. One example of a suitable active agent is an enzyme such as beta-lactamases. In another embodiment, the active agents are those that specifically treat colonic disorders, such as Chrohn's Disease, irritable bowel syndrome, ulcerative colitis, colorectal cancer or constipation. The drug delivery devices are in the form of beads of pectin, crosslinked with calcium and reticulated with polyethyleneimine. The high crosslink density of the polyethyleneimine is believed to stabilize the pectin beads for a sufficient amount of time such that a substantial amount of the active ingredients can be administered directly to the colon. Advantageously, the amount of polyethyleneimine is sufficient to allow a substantial portion of the pectin beads to pass through the gastrointestinal tract to the colon without releasing the active agent, and is also sufficient such that the pectin beads are sufficiently degraded in the colon to release an effective amount of the active agent. |