Reverse Engineering Research In Component Testing Of Ointment Abreva

The ointment Abreva is a non-prescription drug treating lip herpes which was filed by the British company of GlaxoSmithKline.The Abreva was approved by the FDA in 2000 accessing to market.It is a new broad-spectrum antiviral topical cream which can shorten the healing time of ulcers and duration of symptoms.The active pharmaceutical ingredient is n-docosanol which makes up 10% of the content.The product patent of the drug expired on December 13,2013.To study the generics of the Abreva is commercioganic and significant.The reverse engineering in generic drug is a technical reproduction process of product,that is reverse studying a target product to determine the composition,contents and other factors of the product to infer its production process,in order to produce a product which has similar functions but is not same exactly.Its main purpose is deducing the design principles of the product from the product analysis directly in the condition that the necessary product and production information is not available.Reverse engineering involves less in generics industry,more rarely works.With a large number of patent expiration of original drugs,its generic research has not only scientific value but also satisfy the market demand.In this paper,reverse engineering was used to crack the formulations of Abreva.The greatest challenge comes from the mutual interference of each component in the formulation.Compared with traditional chemical quantitative method,the rapid development of modern instrumental analysis techniques provides a condition for more accurate and quick determination.The active pharmaceutical ingredient of Abreva is docosanol which makes up 10% of the formulations.Other excipients include benzyl alcohol,propylene glycol,sucrose stearate,light mineral oil and purified water.We discuss the methods to test the content for each component and select the best solutions for accurate quantification of each component.Purified water was determined by Karl Fischer method;benzyl alcohol and propylene glycol was tested by GC and quantified by external standard method;we also analyzed sucrose stearate using GC and HPLC and used the external standard curve method;reduction method was used to determine the light mineral oil.We compared the results with the patent and tested the viscosity.The results shows that it is reasonable and feasible.In addition,we developed a GC method for behenic acid which is the synthetic material of docosanol and analyzed its system suitability.The method is accurate,convenient and highly sensitive,which can be successfully applied for assay and quality control of behenic acid.