RGRN-305, a novel Hsp90 inhibitor: a promising therapeutic option for inflammatory dermatologic diseases.

Heat shock protein 90 (Hsp90) is a molecular chaperone that plays a critical role in cellular homeostasis and influences various cellular processes. Recent research has revealed its involvement in inflammatory skin diseases, suggesting that Hsp90 inhibitors, such as RGRN-305, may offer therapeutic potential for dermatologic inflammation. This review aims to evaluate the therapeutic role of RGRN-305, a novel Hsp90 inhibitor, in the treatment of inflammatory dermatologic diseases. A comprehensive search was conducted in PubMed/Medline, Scopus, and Web of Science databases up to February 13th, 2025, using keywords related to Hsp90 and RGRN-305, and seven studies were included in the study. Preclinical evidence has demonstrated that RGRN-305 effectively reduces inflammation and modulates immune responses in psoriasis and other skin diseases. Clinical trials revealed significant improvements in disease severity and quality of life for patients with psoriasis and hidradenitis suppurativa treated with RGRN-305. The drug exhibited favorable pharmacokinetic properties, including oral bioavailability, without central nervous system-related toxicity. Safety profiles indicated mild to moderate adverse effects, with no severe events reported in most studies. RGRN-305 shows promising potential as an anti-inflammatory agent in the treatment of autoimmune dermatologic diseases. Larger, randomized clinical trials are required to establish its long-term efficacy and safety.