 SOUTH SAN FRANCISCO, Calif., June 1, 2021 PRNewswire -- Sutro Biopharma, Inc. NASDAQ: STRO, 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 it has received a milestone payment under its collaboration and license agreement with the healthcare division of Merck KGaA, Darmstadt, Germany, related to a patient enrollment achievement in the Phase 1 dose escalation and expansion study of M1231 in adult patients with metastatic solid tumors, including non-small cell lung cancer NSCLC and esophageal squamous cell carcinoma. 