Edaravone is one of two main drugs for treating motor neurone disease (MND). This review proposes a specific quality target product profile (QTPP) for edaravone following an appraisal of the issues accounting for the poor clinical uptake of the approved IV and oral liquid edaravone formulations. This is followed by a review of the alternative oral formulations of edaravone described in the published patent and journal literature against the QTPP. A total of 14 texts published by six research groups on 18 novel oral formulations of edaravone for the treatment of MND have been reviewed. The alternative oral formulations included liquid and solid formulations developed with cyclodextrins, lipids, surfactants, co-surfactants, alkalising agents, tablet excipients, and co-solvents. Most were intended to deliver edaravone for drug absorption in the lower gastrointestinal tract (GIT); however, there were also four formulations targeting the oral mucosal absorption of edaravone to avoid first-pass metabolism. All the novel formulations improved the aqueous solubility, stability, and oral bioavailability (BA) of edaravone compared to an aqueous suspension of edaravone. A common limitation of the published formulations is the lack of MND-patient-centred data. Except for TW001, no other formulations have been trialled in MND patients. To meet the QTPP of an oral edaravone formulation for MND patients, it is recommended that a tablet of appropriate size and with acceptable taste and stability be designed for the effective sublingual or buccal absorption of edaravone. This tablet should be designed with input from the MND community.

Edaravone is used to treat motor neurone disease (MND) by slowing disease progression and prolonging survival time. Currently, it is available as an IV infusion (Radicava^®, Jersey City, NJ, USA) and an oral liquid suspension (Radicava ORS^®, Jersey City, NJ, USA). Development of novel edaravone formulations is still an active field of research that requires a validated stability-indicating assay capable of providing specific, precise, and accurate quantification of edaravone content. In this study, we developed and validated a stability-indicating reversed-phase high-performance liquid chromatography (RP-HPLC) method for edaravone quantification. Ten RP-HPLC methods based on the previously published literature were evaluated during method development. The optimal method employed a gradient method on an Agilent ZORBAX Extend-C18 column (150 × 4.6 mm, 5 µm) and produced a sharp and symmetrical drug peak. The method was further validated according to ICH Q2(R2) guidelines for specificity, linearity, sensitivity, accuracy, and precision. Successful separation of edaravone from void signals and degradant products was achieved. The method was precise and accurate at the concentration range of 6.8–68.6 µg/mL and was recommended to use without methyl hydroxybenzoate (MHB) as an internal standard.