ABSTRACT
BACKGROUND: The antifolate agent methotrexate is routinely used for systemic therapy of cancer and chronic inflammatory diseases. Successful topical use has been described for individual therapeutic attempts, in case series, and small studies, especially for mycosis fungoides (premycotic stage) and lymphomatoid papulosis. With respect to its clinical use in selected treatment scenarios, there have been no approved preparations or regulated instructions for pharmaceutical compounding. MATERIAL AND METHODS: Two high performance liquid chromatography methods were established for the determination of the active substance within a galenic formulation as well as within extracts of biological material. Suitable vehicles for epicutaneous application were developed and preclinically tested for stability, release, and pharmacokinetics of the active substance as well as their safety. RESULTS: The tests show that methotrexate may be readily incorporated into "Basiscreme DAC". It remains stable up to a concentration of 0.5%. This preparation releases enough active substance to achieve relevant local bioavailability in the respective target compartments of the skin. There is no evidence of safety risks due to relevant systemic bioavailability after topical application on a limited area of the skin. CONCLUSIONS: In summary, this approved prescription for extemporaneous preparation complies with the requirements of the German Ordinance on the Operation of Pharmacies (Article 7 ApBetrO), and the available data proves its stability and pharmaceutical quality.
Subject(s)
Delayed-Action Preparations/pharmacokinetics , Drug Compounding/methods , Methotrexate/chemistry , Methotrexate/pharmacokinetics , Skin Absorption/physiology , Skin Cream/chemistry , Administration, Cutaneous , Biological Availability , Delayed-Action Preparations/administration & dosage , Delayed-Action Preparations/chemical synthesis , Drug Stability , Humans , Methotrexate/administration & dosage , Solubility , Suspensions , Treatment OutcomeABSTRACT
The penetration behavior into human nails and animal hoof membranes of a novel antifungal agent (EV-086K) for the treatment of onychomycosis was investigated in this study. The new drug provides a high lipophilicity which is adverse for penetration into nails. Therefore, four different formulations were developed, with particular focus on a colloidal carrier system (CCS) due to its penetration enhancing properties. On the one hand, ex vivo penetration experiments on human nails were performed. Afterwards the human nail plates were cut by cryomicrotome in order to quantify the drug concentration in the dorsal, intermediate and ventral nail layer using high-performance liquid chromatography (HPLC) with UV detection. On the other hand, equine and bovine hoof membranes were used to determine the in vitro penetration of the drug into the acceptor compartment of an online diffusion cell coupled with Fourier transform infrared attenuated total reflectance (FTIR-ATR) spectroscopy. In combination, both results should exhibit a correlation between the EV-086K penetration behavior in human nail plates and animal hoof membranes. The investigations showed that the developed CCS could increase drug delivery through the human nail most compared to other formulations (nail lacquer, solution and hydrogel). Using animal hooves in the online diffusion cell, we were able to calculate pharmacokinetic data of the penetration process, especially diffusion and permeability coefficients. Finally, a qualitative correlation between the penetration results of human nails and equine hooves was established.