BST-12

BST-12 is a novel small molecule prodrug belonging to the N-Benzyl Indole Carbinol (N-BIC) class, developed by Brimstalt Therapeutics for the treatment of cancers expressing the tumor-associated enzyme (TAE) sulfotransferase 1A1 (SULT1A1). The drug is specifically activated within cancer cells by SULT1A1, which converts the prodrug into a potent, non-specific alkylating agent. This mechanism leads to targeted DNA damage and subsequent cancer cell death while sparing normal tissues that express low or no levels of the enzyme. Preclinical studies in renal cell carcinoma (RCC) models have demonstrated that BST-12 is highly potent in SULT1A1-positive cell lines (such as A498 and Caki-1) with IC50 values under 250 pM, and it has shown the ability to rapidly eliminate established tumors in vivo with a favorable tolerability profile in rat models.