 SOUTH SAN FRANCISCO, Calif., April 15, 2021 PRNewswire -- Sutro Biopharma, Inc. NASDAQ: STRO, a clinical-stage drug discovery, development and manufacturing company focused on the application of precise protein engineering and rational design to create next-generation cancer and autoimmune therapeutics, today announced that Merck, known as MSD outside the United States and Canada, will make to Sutro a 15 million milestone payment for the initiation of an IND enabling toxicology study for the first program in its collaboration to develop novel cytokine derivative therapeutics for cancer and autoimmune disorders. 