Considerations in the Development of Topical Therapies for Proliferative Dermatoses

1. Considerations in the Development of Topical Therapies for Proliferative Dermatoses Ryan Davis James Shoemaker, M.D., Ph.D. June 3, 2003

2. Points of Focus • Proliferative Dermatoses • Ceramides • Role in topical therapies

3. Proliferative Dermatoses • Psoriasis • Inflammation • Red base • Pustules • Scaling • Itching • Eczema • Seborrhea

4. Pathology • Hyperproliferation of epidermal cells • Abnormal keratin production • Dermal inflammation • Autoimmune component

5. Psoriasis histology • Normal cells migrate to upper layer in about a month, while in psoriasis – a few days

6. Ceramides • Biosynthesis • Cell signaling

9. Different vitamin D analogues induce sphingomyelin hydrolysis and apoptosis in the human keratinocyte cell line HaCaT. • Sphingomyelin hydrolysis seems to be a ubiquitous pathway generating ceramide, an important cell response modifier. Upon agonist-stimulation this pathway is linked to biological responses as inhibition of proliferation, promotion of differentiation and induction of apoptosis. One of the agonists described is 1alpha,25-dihydroxyvitamin D3. • This study indicates that sphingomyelin hydrolysis, subsequently leading to the elevation of cellular ceramide levels, may represent an important signal transduction pathway for 1alpha,25-dihydroxyvitamin D3 and its analogues in human keratinocytes. Bektas M, Orfanos CE, Geilen CC. Cell Mol Biol (Noisy-le-grand). 2000 Feb;46(1):111-9.

10. Sphingomyelin Hydrolysis

11. Ceramides… • From Yong Wei, et al, US Patent 5,631,394 • …attachment of certain chemical groups to sphingolipids and ceramides so as to form analogs of such compounds can inhibit bioconversion of ceramides to sphingomyelins, and can thereby lead to an apoptosis stimulating increase in ceramide concentrations. • From Crandall, et all US Patent 6,306,383 • Sphingosine dose-dependently inhibits Protein Kinase C … • PKC inhibition leads to decreased hyperproliferation • Ultimately, increased ceramide concentrations should decrease hyperproliferation

12. Appropriate vehicle Medium Chain Triglyceride (MCT) Magnesium Stearate Formulated at: 50% MCT oil 48% Mg-Stearate 2% C6-Ceramide Chemical Analysis Quality Control LC-MS-MS (QStar) Stability Studies Our Work Completed Future

13. C6 Ceramide provided by:

14. Seborrhea, June 3, 2003

15. Seborrhea July 2, 2003