(Hong Kong, 23 July 2020) TOT BIOPHARM International Company Limited (“TOT BIOPHARM” or the “Company”; stock code: 1875.HK) is pleased to announce that TOT BIOPHARM’s self-developed HER2 targeted antibody drug conjugate (“ADC”) candidate, TAA013, has recently reached a key clinical-stage milestone. The first patient has been successfully dosed in a pivotal Phase III registrational clinical trial (the “Study”). The purpose of the study is to evaluate the efficacy and safety of TAA013 as compared to lapatinib plus capecitabine in the treatment of patients with unresectable locally advanced or metastatic HER2-positive breast cancer after failure of trastuzumab therapy. If successful, the study will be used to support the new drug application for TAA013 in China.

TAA013 is the ADC owned by TOT BIOPHARM which has shown the fastest growth. It is an ADC conjugated from trastuzumab monoclonal antibodies and the high activity substance DM1 through the linker. In addition to having the same anti-tumor efficacy as trastuzumab monoclonal antibodies, TAA013 also delivers DM1 with a high cytotoxicity but a low therapeutic index to the target cells, conducive to safety as well as realising greater anti-cancer impact and reducing the rate of relapse. Through TAA013, TOT BIOPHARM aims to offer a quality and affordable treatment choice to breast cancer patients.

Ms. Yeh-Huang, Chun-Ying, General Manager of TOT BIOPHARM, said, “We are greatly encouraged by the first patient dosed in the Phase III Clinical Trial of TAA013. At present, we are building the ADC commercial production workshop, which is expected to become one of the few ADC commercial production workshops in China, thus bringing first-mover advantage as well as laying a foundation for further development in the ADC market. TAA013 is the first ADC product under the generic name (INN) of T-DM1 to have entered Phase III clinical trial in the Chinese market. We believe that prospects are promising after the successful commercial production of TAA013, which will generate even greater profits and become a key new growth driver for TOT BIOPHARM.”