Sutro Biopharma

Sutro Biopharma is a clinical-stage oncology company that designs and develops site-specific antibody-drug conjugates (ADCs) and novel-format therapeutics using its proprietary XpressCF and XpressCF+ platforms. Unlike conventional cell-based synthesis, the firm’s technology decouples cell mass production from protein production by using a proprietary highly engineered E. coli extract called XtractCF. This cell-free system allows for the expression of complex mammalian proteins in less than 24 hours, a significant reduction from the 30 to 40 days required by traditional methods. The platform enables the simultaneous expression of thousands of DNA sequences to rapidly evaluate protein structure-activity relationships, optimizing properties such as binding efficiency, stability, and target killing. A key differentiator is the precise incorporation of non-natural amino acids at specific locations, allowing for the creation of homogeneous molecules with optimized "warhead" placement and drug-antibody ratios (DAR) that can exceed eight. Additionally, proteins produced via XpressCF do not bind to the Fc-gamma...