Securities code: 688506 Securities abbreviation: Baili Tianheng Announcement No.: 2024-054

Sichuan Baili Tianheng Pharmaceutical Co., Ltd

About the BL-B01D1 combination program for the treatment of 1/2a of advanced solid tumors

Announcement of FDA clearance for Phase 1 clinical trial application

The board of directors and all directors of the company guarantee that there are no false records, misleading statements or material omissions in the content of this announcement, and assume legal responsibility for the authenticity, accuracy and completeness of its content in accordance with the law.

Recently, Bristol-Myers Squibb (hereinafter referred to as "BMS", NYSE: BMY), a partner of Sichuan Baili Tianheng Pharmaceutical Co., Ltd. (hereinafter referred to as the "Company"), received a notice from the United States Food and Drug Administration (hereinafter referred to as the "FDA") that the Phase 1/2a clinical trial application of BL-B01D1 combination drug program for the treatment of advanced solid tumors has been approved by the FDA, and the relevant information is hereby announced as follows:

1. Basic information of this license

Drug Name: BL-B01D1 Combination Drug

Indications: Advanced solid tumors

Approval conclusion: The FDA has approved this product to carry out clinical studies

Second, the basic information of the drug

BL-B01D1 is the world's first and only clinical-stage bispecific antibody targeting EGFR×HER3

ADC。 In December 2023, the company entered into an exclusive licensing and cooperation agreement with BMS for the BL-B01D1 project.

This collaboration will accelerate the global clinical development and commercialization of BL-B01D1 for multiple malignancies. For details, please refer to the "Announcement of Sichuan Baili Tianheng Pharmaceutical Co., Ltd. on the Global Strategic Cooperation Agreement between SystImmune, a Wholly-owned Subsidiary, and Bristol-Myers Squibb on the Development and Commercialization Rights of BL-B01D1" (Announcement No.: 2023-057) disclosed by the Company on the website of the Shanghai Stock Exchange (www.sse.com.cn).

BL-B01D1 is underway in more than 20 clinical trials in China and United States for multiple tumor types.

Includes (i) 7 Phase III clinical trials, including 2, evaluating BL-B01D1 monotherapy for the post-line treatment of cancer

Non-small cell lung cancer indication, 1 small cell lung cancer indication, 2 breast cancer indications, 1 esophageal squamous squamous

carcinoma indications, 1 indication for nasopharyngeal carcinoma, (ii) evaluated in combination with PD-(L)1 therapy for the first-line treatment of 9 cancers

Indications (small cell lung cancer, non-small cell lung cancer, nasopharyngeal cancer, head and neck squamous cell carcinoma, esophageal cancer, gastric cancer, nodules

rectal, breast, and urothelial carcinoma) and (iii) evaluating it in combination with TKIs

2 phase II trials in the first-line treatment of lung cancer.

3. Impact on the company and risk warning

The clinical study of BL-B01D1 combination has been approved by the FDA for IND and will be further promoted

The process of the company's business and product internationalization layout, deepening the company's further cooperation with BMS on this product, is expected to have a positive impact on the company's long-term operating performance.

According to the requirements of laws and regulations related to the registration of United States drugs, after obtaining clinical trial approval, drugs still need to carry out clinical trials and be approved by the FDA before they can be marketed.

Due to the characteristics of high-tech, high-risk and high value-added pharmaceutical products, drugs from early research, clinical trial approval to production cycle is long and linked, and are easily affected by some uncertain factors.

The announcement is hereby made.

Board of Directors of Sichuan Baili Tianheng Pharmaceutical Co., Ltd

September 30, 2024