Research Article Formulation and Development of a Water-in-Oil Emulsion-Based Luliconazole Cream: In Vitro Characterization and Analytical Method Validation by RP-HPLC Vijay Kumar Panthi 1,2,3,4 and Utsav Nepal 5,6 1 Department of Pharmacy, Tribhuvan University, Sunsari Technical College, Sunsari, Nepal 2 Research & Development Department, Royal Sasa Nepal Pharmaceuticals, Chitwan, Nepal 3 Research & Development Department, Asian Pharmaceuticals, Rupandehi, Nepal 4 Research & Development Department, Corel Pharmaceuticals, Rupandehi, Nepal 5 Department of Pharmacy, Kathmandu University, School of Science, Dhulikhel, Nepal 6 Quality Control Department, Royal Sasa Nepal Pharmaceuticals, Chitwan, Nepal Correspondence should be addressed to Vijay Kumar Panthi; nepalivijay7@gmail.com Received 5 July 2022; Revised 5 August 2022; Accepted 10 August 2022; Published 23 September 2022 Academic Editor: Suresh Ponnayyan Sulochana Copyright © 2022 Vijay Kumar Panthi and Utsav Nepal. is is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Luliconazole (LCZ) is a new antifungal agent containing imidazole moiety which revealed broad-spectrum antifungal activity. e aim of this research was to prepare water-in-oil (w/o) emulsion-based cream formulation of LCZ in addition to the development and validation of an analytical method by reverse-phase high-performance liquid chromatography (RP-HPLC). Cetostearyl alcohol (12.14%), light liquid paraffin (5.00%), white soft paraffin (2.75%), and Tween-80 (1.00%) appeared as the optimized concentration to give better consistency to the cream. Moreover, without adding pH adjusting agents the pH of the optimized formulation (F5) was obtained within the range of human skin pH throughout the stability period. e value of particle size, polydispersity index, and zeta potential was 187.90 ± 2.061 nm, 0.124 ± 0.026, and -10.553 ± 1.349 mV, respectively. In this study, an analytical C18 (4.6 mm × 25 cm), 5 μm column was used for chromatographic separation with a mixture of acetonitrile and water in the proportion of 50 : 50 v/v as the mobile phase at a flow rate of 1.0 mL/min. e calibration curve was obtained linear at 296 nm in the concentration range of 0.08–0.12 mg/mL. Furthermore, the limit of detection (LOD) and limit of quantification (LOQ) were 0.0013 and 0.0042 µg/mL, respectively. In addition, the observed results demonstrated that our developed method was linear (R2 = 0.999), precise (%RSD below than 2.0%), and accurate (mean recovery% = 100.18–100.91). e F5 showed no physical changes until 6th month analysis at room temperature and accelerated conditions. Similarly, the assay obtained 101.99% ± 0.27 and 99.89% ± 0.08 at room temperature and accelerated conditions, respectively. Additionally, all validated parameters were obtained within the acceptable limit as well. ese findings conclude that both physically and chemically stable w/o cream formulation of LCZ can be formulated and assessed for their stability by applying the authenticated analytical procedure of RP- HPLC. 1. Introduction Luliconazole (LCZ) is a new antifungal agent consisting of imidazole moiety with a broad range of antifungal properties that is structurally associated with its predecessor, lan- oconazole [1]. e LCZ has demonstrated its broad range of potentiality against various fungal infections including dermatophytes and onychomycosis [2]. However, the mechanism of its antifungal efficacy is still unclear. e previously published research has reported that this new drug reveals its action by impeding the fungal cytochrome P450; that is, 14-α dimethyl enzyme thus inhibits the bio- synthesis of ergosterol from lanosterol and then finally hinders the cell wall synthesis within the fungi [3, 4]. Hindawi International Journal of Analytical Chemistry Volume 2022, Article ID 7273840, 12 pages https://doi.org/10.1155/2022/7273840