Abstract: A press-coated tablet suitable for oral administration, comprising an immediate-release compartment comprising a compressed blend of an active agent. The immediate-release compartment has a dissolution profile in which 10-75% of the active agent is dissolved within one hour and not less than 90% of the active agent is dissolved within 6 hours. The tablet further comprises an extended-release compartment with a dissolution profile in which 5-40% of the active agent is dissolved within one hour, 20-75% within three hours, 40-95% of the active agent within 6 hours, and not less than 60% of the active agent is dissolved within 8 hours. Additionally, the press-coated extended-release compartment substantially envelops the immediate-release compartment, and comprises a compressed blend of the active agent, a hydrophilic polymer and hydrophobic material. The tablet exhibits a first order release of the active agent interrupted by a pulsed delivery of the active agent.

Abstract: A press coated, pulsatile drug delivery system suitable for oral administration having an immediate-release compartment, which contains a compressed blend of an active agent and one or more polymers, substantially enveloped by an extended-release compartment, which contains a compressed blend of the active agent and hydrophilic and hydrophobic polymers, can provide a substantially first order delivery of the active agent, interrupted by a timed, pulsed delivery of an increased amount of the active agent; and when the extended-release compartment is substantially enveloped by an optional instant-release compartment, can provide a dose sufficient to exceed the liver's metabolic capacity and to maintain therapeutic levels, preferably throughout a 24-hour period.