Analytical Method and Stability Study for Oral Suspension of Idebenone in Syrspend

Abstract

Idebenone (IDB) (2,3-dimethoxy-5-methyl-6-(10-hydroxydecyl)-1,4-benzoquinone) is a compound synthesized in the early 1980s. Initially developed for the treatment of cognitive disturbances and Alzheimer’s disease, IDB is now studied for Friedreich’s ataxia, Leber’s hereditary optic neuropathy (LHON), or Duchenne muscular dystrophy. The greatest disadvantage of IDB is its low solubility in water, resulting in low bioavailability. Galenic preparations of IDB in customized doses are common for pediatric patients, which can often prove to be the only option for access to therapy. As an antioxidant, the chemical stability of IDB is an essential guarantee for exerting the desired antioxidant action. Stability studies are essential to know the effect of storage conditions of a galenic product. For the first time, a stability-indicating LC-MS method has been developed to define the stability of IDB suspensions in SyrSpend® Sugar-Free Unflavored (Fagron), a carrier phase formulated for setting up suspensions of active pharmaceutical ingredients (APIs) insoluble or poorly insoluble in water and compatible with it. The proposed method was validated for linearity, accuracy, specificity, robustness, matrix effect and recovery, limit of detection (LOD), limit of quantification (LOQ), and repeatability.