Treos Bio ZRT OBERTO -101 Amendment 3 Product: PolyPEPI 1018 Colorectal Cancer Vaccine Page 1 of 81 CONFIDENTIAL CLINICAL STUDY PROTOCOL Protocol Title: A Phase 1, Multiple doses, Multicenter, Open -label Study t o Evaluate Safety, Tolerability, Immunogenicity and Efficacy of Subcutaneous Injections of PolyPEPI1018 Vaccine as an Add -on Immunotherapy to the Standard -of-Care Maintenance Therapy in Subjects with Metastatic C olorectal Cancer (OBERTO) Short Protocol Title: Safety and Immunogenicity of PolyPEPI 1018 Vaccine in the Treatment of M etastatic C olorectal Cancer (OBERTO) Protocol Number: OBERTO -101 Amendment 3 Name of Investigational Product: PolyPEPI 1018 CRC Vaccine (PolyPEPI1018) IND Number: 17887 #0001 EudraCT Number: 2017-003850-18 Sponsor: Treos Bio ZRT Viola utca, 2 8200 Veszprém Hungary Study Medical Monitor: Franco Lori, M.D., Ph.D. Chief Medical Officer at Treos Bio ZRT Phone: +39 347 0723942 FAX: +36-1-332-3636 E-mail: franco.lori@ treosbio.com Original Protocol Date: 15 November 2017 Amendment 1 Date 15 January 2018 Amendment 2 Date August 21 2018 Amendment 3 Date April 10 2019 Confidentiality Statement: This document contains information that is the confidential and proprietary property of Treos Bio ZRT.