Formulation, Development and Evaluation of Pulsatile Drug Delivery of Rizatriptan for Chronotherapy of Migraine

Migraine is a common neurological disorder characterized by recurrent attacks of moderate-to-severe headache, often accompanied by nausea, vomiting, photophobia and phonophobia. The onset of migraine attacks demonstrates temporal variability, with several clinical studies reporting a predominance of attacks during the early morning hours. Conventional immediate-release rizatriptan provides rapid symptomatic treatment but does not address the temporal pattern of migraine occurrence. Pulsatile drug delivery systems are designed to provide a predetermined lag time followed by rapid drug release and therefore offer a promising approach for chronotherapy. The present research proposes the formulation and evaluation of a pulsatile oral drug delivery system containing rizatriptan, designed to provide a controlled lag period followed by rapid drug release corresponding to the anticipated period of migraine attack. Rizatriptan was selected because of its established antimigraine activity and relatively short elimination half-life, making temporal control of drug availability a potentially useful formulation strategy. The proposed formulation is expected to remain substantially intact during the predetermined lag period and subsequently produce a rapid pulse of rizatriptan. Such a system could potentially synchronize drug availability with the circadian pattern of migraine and reduce the delay between drug administration and anticipated attack onset. Further in-vivo and clinical studies would be necessary to establish its therapeutic superiority over conventional rizatriptan formulations.