Method development and validation of newly approved Tapinarof in its estimation in the marketed formulation using HPLC-PDA detection, along with Stability studies.

AbstractBackground: Tapinarof is a newly approved novelAhR agonist for plaque psoriasis andatopic dermatitistreatment. To control quality and remain compliant with regulations, there isa requirement to develop sensitive, stability-indicating analytical techniques.Purpose: This was done to design and establish a sensitive, high-performance, and rapid RPHPLC-PDA technique to quantify Tapinarof in both bulk drug and topical cream preparations,particularly under different strain conditions to assess the drug's stability.Methods: YMC Triart C18 column (250 x 4.6 mm, 5 μm) was used for the Chromatographicseparation with10 mM Ammonium acetate and Acetonitrile (20: 80 v/v) as the mobile phaseat 1.0 mL/min. At 313 nm, chromatographic separation occurred, and the method wasvalidated in accordance with ICH Q2(R1) guidelines, along with forced degradation studies todetermine the drug's stability.Outcomes: Tapinarof retention time was found to be 4.128 min. Linearity (R2 = 0.999) forthe dilutions between 96 and 360 ng/mL for this method. The level of precision was high, asthe intraday and Interday studies showed the influence of the % RSD of 0.17 and 0.28,respectively. The commercial cream formulation assay had a recovery of 99.65%.Exaggerated degradation showed that Tapinarof is very vulnerable to both base hydrolysis(27.68% degradation) and oxidative stress (26.44%), but it is relatively resistant to thermalstress. Every degradation product was clearly separated from the major peak.Summary: The developed RP-HPLC technique is fast, economical, and stability-indicatingfor Tapinarof in its dosage forms.