A pharmaceutical dosage form such as a capsule capable of delivering therapeutic
agents into the body in a time-controlled or position-controlled pulsatile release
fashion, is composed of a multitude of multicoated particulates (beads, pellets,
granules, etc.) made of one or more populations of beads. Each of these beads except
an immediate release bead has at least two coated membrane barriers. One of the
membrane barriers is composed of an enteric polymer while the second membrane barrier
is composed of a mixture of water insoluble polymer and an enteric polymer. The
composition and the thickness of the polymeric membrane barriers determine the
lag time and duration of drug release from each of the bead populations. Optionally,
an organic acid containing intermediate membrane may be applied for further modifying
the lag time and/or the duration of drug release. The pulsatile delivery may comprise
one or more pulses to provide a plasma concentration-time profile for a therapeutic
agent, predicted based on both its pharmaco-kinetic and pharmaco-dynamic considerations
and in vitro/in vivo correlations.