Summary of Conference Call Notes Company and Industry Overview - The conference call discusses **Ying En Bio** and its clinical developments in the field of oncology, particularly focusing on **DB-1,311 (B7-H3 ADC)** for treating **castration-resistant prostate cancer (CRPC)** [2][5][14]. Key Points and Arguments DB-1,311 (B7-H3 ADC) Efficacy and Safety - **DB-1,311** shows significant anti-cancer activity in heavily pre-treated CRPC patients, including those who have undergone nuclear medicine treatment and those who have not received taxane therapy [2][4]. - The **FURTHER study** included 73 advanced or metastatic CRPC patients, demonstrating an overall objective response rate (ORR) of **31%** and a disease control rate (DCR) exceeding **90%** [2][8]. - The ORR for the 6 mg and 9 mg dose groups was **42%** and **43%**, respectively, indicating substantial and durable anti-tumor activity [8][10]. - Radiographic progression-free survival (PFS) data showed that only **20.6%** of patients experienced confirmed disease progression, with a **6-month RPFS rate of 67%** and a **9-month RPFS rate of 58%** [10]. Patient Demographics and Treatment Background - The 73 patients in the FURTHER study were from the US (44%), Australia (29%), and East Asia (27%), with a median treatment duration of **4.8 months** [7]. - These patients had undergone multiple lines of prior treatment, including hormone therapy, docetaxel, cabazitaxel, nuclear medicine, platinum-based chemotherapy, immunotherapy, and PARP inhibitors, indicating a poor prognosis and typically low response to new drugs [7][11]. Safety Profile - Among the 73 patients, the incidence of treatment-related grade 3 or higher adverse events was **42.5%**, with the 6 mg dose group showing a lower rate of **28.9%** compared to the 9 mg group at **60%** [13]. - The overall permanent discontinuation rate was low at **6.5%**, with gastrointestinal and hematological toxicities primarily at grade 1 or 2 [13]. Future Development and Research Directions - DB-1,311 has received **FDA Fast Track designation**, and further studies are ongoing to optimize dosing and evaluate its efficacy in various patient cohorts [5][6]. - The company is actively recruiting patients for ongoing studies, including those who have undergone nuclear medicine treatment and taxane-naive patients [6][14]. HER3 ADC Developments - The conference also highlighted the **DB1,310 project**, a novel ADC targeting HER3, which has shown promising results in heavily pre-treated advanced solid tumor patients, with an ORR of **31%** and a DCR of **84%** [15][16]. - The project is currently in clinical trials in the US and China, with a focus on optimizing dosing and evaluating safety [18][20]. Additional Important Insights - The waterfall plot analysis indicated that nearly all patients experienced some degree of tumor shrinkage, with many achieving partial response (PR) [9][27]. - The company is considering various strategies for maximizing drug value, including starting from later lines of treatment and gradually moving to earlier lines [32]. - The collaboration with **Biotech** for the development of DB-1,311 and the potential for joint commercialization is under discussion, reflecting the positive data observed so far [35][38]. This summary encapsulates the critical findings and future directions discussed during the conference call, emphasizing the promising developments in oncology therapeutics by Ying En Bio.