Sienna Biopharmaceuticals, Inc. announced biopsy data from its recent Phase 2b clinical trial with SNA-120 (pegcantratinib), the Company’s Phase 3 topical, non-steroidal Tropomyosin receptor kinase A (TrkA) inhibitor under investigation for the treatment of psoriasis. Biopsy analyses were conducted at The Rockefeller University on 22 subjects, and included Immunohistochemistry (IHC), MicroArray and quantitative Reverse Transcription Polymerase Chain Reaction (qRT-PCR). The clear and substantial impact by Sienna’s SNA-120 on immune cells and the vast array of important psoriasis-related pathways after 12 weeks of treatment is impressive and encouraging for a topical, non-steroidal treatment,” said James G. Krueger, D. Martin Carter Professor in Clinical Investigation, Director, Milstein Medical Research Program, and Senior Attending Physician at the Laboratory for Investigative Dermatology, The Rockefeller University. Specifically, the Immunohistochemistry analysis showed meaningful and statistically significant improvement in the epidermal thickness at Week 12, supporting the effect of SNA-120 (0.05%) on keratinocyte hyperproliferation and inflammation. In addition, the data demonstrated a statistically significant reduction in T cell and dendritic cell counts, confirming an immune response to treatment with SNA-120. In MicroArray analyses, SNA-120 (0.05%) was also observed to affect most of the key inflammatory pathways in psoriasis (40 of 45) in a statistically significant manner when compared to vehicle at Week 12. In the qRT-PCR analysis, SNA-120 (0.05%) demonstrated substantial, statistically significant gene expression improvements in key cytokines that play an important role in psoriasis pathogenesis, including IL-23, IL-12, IL-17A and IFNg, among other cytokines, in PASI 75 responders and even led to restoration to non-lesional expression levels, further validating the strong pharmacological effect of SNA-120.