TRANSTHERA-B - VOLUNTARY ANNOUNCEMENT

FIRST PATIENT DOSED IN CONFIRMATORY PHASE III CLINICAL TRIAL OF TINENGOTINIB MONOTHERAPY FOR THE TREATMENT OF PATIENTS WITH ADVANCED CHOLANGIOCARCINOMA

TransThera Sciences (Nanjing), Inc. 藥捷安康 ( 南京 ) 科技股份有限公司

(A joint stock company incorporated in the People's Republic of China with limited liability) (Stock Code: 2617)

VOLUNTARY ANNOUNCEMENT

FIRST PATIENT DOSED IN CONFIRMATORY PHASE III CLINICAL TRIAL OF TINENGOTINIB MONOTHERAPY FOR THE TREATMENT OF PATIENTS WITH ADVANCED CHOLANGIOCARCINOMA

This announcement is made by TransThera Sciences (Nanjing), Inc. (the "Company", together with its subsidiaries, the "Group") on a voluntary basis to inform the shareholders and potential investors of the Company about the latest business advancement of the Group.

The Company announces that the first patient has been recently dosed in the confirmatory Phase III clinical trial of Tinengotinib (TT-00420), one of the Company's core products, as a monotherapy for the treatment of patients with advanced cholangiocarcinoma (CCA).

This trial is a randomized, controlled, open-label and multi-center Phase III clinical study conducted in China to evaluate the efficacy and safety of Tinengotinib versus chemotherapy in patients with unresectable advanced or metastatic intrahepatic CCA harboring FGFR2 fusion/ rearrangement or mutation, who have relapsed or progressed following first-line systemic therapy in the prior treatment.

The global CCA drug market reached USD2 billion in 2024 and is projected to grow to USD3.2 billion by 2027. Approximately 25.2% of CCA patients present with FGFR alterations. According

to a research paper published in Cancer Treatment Reviews in 2023, patients with CCA develop acquired resistance following treatment with FGFR inhibitors. The pivotal Phase II clinical trial of Tinengotinib has been completed in China, and its New Drug Application (NDA) has been submitted to and accepted for review by the National Medical Products Administration (NMPA). Tinengotinib is the world's first and only investigational product seeking marketing approval for the treatment of relapsed or refractory CCA patients previously treated with FGFR inhibitors. Meanwhile, Tinengotinib is undergoing the international multi-center Phase III clinical trial overseas.

ABOUT TINENGOTINIB

Tinengotinib is an internally discovered, NDA stage, innovative multi-target small molecule kinase inhibitor that exerts antitumor effects by targeting tumor cells and improving the tumor microenvironment. Currently, multiple clinical trials of Tinengotinib are ongoing globally, targeting various solid tumors such as CCA, prostate cancer, breast cancer and liver cancer. It was granted the Priority Review and Approval Procedure and the Breakthrough Therapy Designation (BTD) by the NMPA in China, the Orphan Drug Designation (ODD) and Fast Track Designation by the FDA for the treatment of CCA, and the Orphan Drug Designation (ODD) for the treatment of biliary tract cancer by the European Medicines Agency (EMA).

Warning under Rule 18A.08(3) of the Listing Rules: There is no assurance that the relevant products will ultimately be successfully developed and marketed by the Company.

By order of the Board

TransThera Sciences (Nanjing), Inc. 藥捷安康(南京)科技股份有限公司 Dr. Frank Wu Chairman and Chief Executive Officer

Hong Kong, 17 April, 2026