Development and Validation of Stability-indicating Analytical Method for a Multiparticulate Drug Delivery System Containing Rizatriptan Benzoate

Abstract

A stability-indicating analytical method was developed for a newly formulated multiparticulate drug delivery
system containing rizatriptan benzoate that is meant for administration by the sublingual route. A forced
degradation study was performed to determine the breakdown products of rizatriptan benzoate. Subsequently,
a high-performance liquid chromatography (HPLC)-based analytical method was developed to estimate the
shelf-life of a multiparticulate drug delivery system. The HPLC parameters were deliberately varied to validate
the robustness and ruggedness of the analytical method. This validated method was then used to propose the
shelf-life of a newly formulated drug delivery system of rizatriptan benzoate stored at 40 ± 2°C and 75 ± 5%
RH for 6 months. Forced degradation studies revealed significant degradation under acidic, oxidative, and
photolytic conditions, while the drug was stable under neutral and thermal stress. The developed HPLC method
successfully separated the drug from its degradation products with good resolution. The developed HPLC
method qualified for accuracy, precision, specificity, linearity, robustness, and sensitivity. Validation studies
demonstrated accuracy of 98.6%, precision (RSD <2%), linearity (R2
= 0.999), and robustness. The results of the
stability study indicated that the formulation did not exhibit significant changes when packed in paper sachets
and stored at accelerated stability conditions for 6 months. Therefore, it is proposed that the multiparticulate
drug delivery system containing rizatriptan benzoate, when packed in paper sachets, can be stored for a period
of up to 24 months at room temperature. However, the results need to be confirmed by performing real-time
stability studies in future work.