Suzhou, China, December 8th, 2025—CStone Pharmaceuticals (“CStone,” HKEX: 2616), an innovation-driven biopharmaceutical company focused on the research and development of therapies for oncology, autoimmune/inflammation, and other key disease areas, today announced that GAVRETO^® (pralsetinib, 100 mg) has been included in the latest National Reimbursement Drug List (NRDL), released by China’s National Healthcare Security Administration. The latest NRDL will become effective on January 1, 2026.

About GAVRETO^® (pralsetinib)

GAVRETO^® is a once-daily oral targeted therapy approved by the National Medical Products Administration (NMPA) of China for the treatment of adults with locally advanced or metastatic RET fusion-positive Non-Small Cell Lung Cancer (NSCLC), and for the treatment of adult and pediatric patients 12 years of age and older with advanced or metastatic RET-mutant Medullary Thyroid Carcinoma (MTC) who requires systemic therapy, and adult and pediatric patients 12 years of age and older with advanced or metastatic RET fusion-positive thyroid cancer who requires systemic therapy and radioactive iodine-refractory (if radioactive iodine treatment is appropriate).

GAVRETO^® has been approved in Hong Kong, China for the treatment of adult patients with RET fusion-positive metastatic NSCLC, and in Taiwan, China for the treatment of adult patients with locally advanced or metastatic RET fusion-positive NSCLC, advanced or metastatic RET-mutant MTC who require systemic therapy, and advanced or metastatic RET fusion-positive thyroid cancer who require systemic therapy and who are radioactive iodine-refractory (if radioactive iodine is appropriate).

GAVRETO^® is approved by the U.S. Food and Drug Administration (FDA) for the treatment of:

• Adult patients with metastatic RET fusion-positive NSCLC as detected by an FDA approved test
• Adult and pediatric patients 12 years of age and older with advanced or metastatic RET fusion-positive thyroid cancer who require systemic therapy and who are radioactive iodine-refractory (if radioactive iodine is appropriate)^*

*This indication is approved under accelerated approval based on Objective Response Rate (ORR) and duration of response (DOR). Continued approval for this indication may be contingent upon verification and description of clinical benefit in confirmatory trial(s).

GAVRETO^® was discovered by CStone’s partner, Blueprint Medicines (acquired by Sanofi in July 2025). CStone has an exclusive collaboration and license agreement with Blueprint Medicines for the development and commercialization of GAVRETO^® in Greater China, which encompasses Mainland China, Hong Kong, Macau and Taiwan. In November 2023, CStone announced an exclusive agreement with Shanghai Allist Pharmaceuticals Co., Ltd. to commercialize GAVRETO^® in Mainland China.

About CStone

CStone (HKEX: 2616), established in late 2015, is an innovation-driven biopharmaceutical company focused on the research and development of therapies for oncology, autoimmune/inflammation, and other key disease areas. Dedicated to addressing patients’ unmet medical needs in China and globally, the Company has made significant strides since its inception. To date, the Company has successfully launched 4 innovative drugs and secured approvals for 16 new drug applications covering 9 indications. The company’s pipeline is balanced by 16 promising candidates, featuring potentially first-in-class or best-in-class antibody-drug conjugates (ADCs), multispecific antibodies, immunotherapies and precision medicines. CStone also prides itself on a management team with comprehensive experiences and capabilities that span the entire drug development spectrum, from preclinical and translational research to clinical development, drug manufacturing, business development, and commercialization.For more information about CStone, please visit: www.cstonepharma.com.

IR contact: ir@cstonepharma.com

PR contact: pr@cstonepharma.com

Forward-looking statements

The forward-looking statements made in this article only relate to events or information as of the date when the statements are made in this article. Except as required by law, we undertake no obligation to update or publicly revise any forward-looking statements, whether as a result of new information, future events or otherwise, after the date on which the statements are made or to reflect the occurrence of unanticipated events. You should read this article completely and with the understanding that our actual future results or performance may be materially different from what we expect. All statements in this article are made on the date of publication of this article and may change due to future developments.

Disclaimer: only for communication and scientific use by medical and health professionals, it is not intended for promotional purposes.

Blueprint Medicines and associated logos are trademarks of Blueprint Medicines Corporation. GAVRETO^® and associated logos are trademarks of Blueprint Medicines Corporation outside of the United States.