Suzhou, China, November 25th, 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 the European Commission (EC) has approved a new indication for sugemalimab as a monotherapy for adult patients with unresectable stage III non-small cell lung cancer (NSCLC) with PD-L1 expression on ≥1% of tumour cells and no sensitising EGFR mutations, or ALK, ROS1 genomic aberrations and whose disease has not progressed following platinum-based chemoradiotherapy (CRT).

Dr. Jason Yang, CEO, President of R&D, and Executive Director at CStone, stated, “Coming about a year after the initial EC approval for first-line metastatic NSCLC, this second approval expands the indication for sugemalimab to cover the full spectrum of the disease—from locally advanced, unresectable Stage III to metastatic Stage IV—across Europe. This provides a new treatment option for a broader patient population. CStone remains committed to enhancing the global accessibility of sugemalimab and fulfilling our long-term promise to patients.”

Dr. Qingmei Shi, Chief Medical Officer of CStone, added, “With its approval as the second PD-(L)1 antibody in Europe for Stage III NSCLC, sugemalimab is poised to address a critical unmet medical need. This achievement was made possible by the exceptional efforts of our clinical development and regulatory teams, which facilitated the European Medicines Agency (EMA)’s smooth and quick review process. We are committed to further enhancing our global capabilities to deliver our innovative pipeline to patients around the world.”

About Sugemalimab

The anti-PD-L1 monoclonal antibody sugemalimab was developed by CStone using OmniRat^® transgenic animal platform, which allows creation of fully human antibodies in one step. Sugemalimab is a fully human, full-length anti-PD-L1 immunoglobulin G4 (IgG4) monoclonal antibody, which may reduce the risk of immunogenicity and toxicity for patients, a unique advantage over similar drugs.

The EC has approved sugemalimab for two indications:

• In combination with platinum-based chemotherapy for the first-line treatment of patients with metastatic NSCLC with no sensitizing EGFR mutations, or ALK, ROS1 or RET genomic tumor aberrations (This indication has also been approved by the Medicines and Healthcare products Regulatory Agency [MHRA]);
• Monotherapy for adult patients with unresectable stage III NSCLC with PD-L1 expression on ≥1% of tumour cells and no sensitising EGFR mutations, or ALK, ROS1 genomic aberrations and whose disease has not progressed following platinum-based CRT. 

The National Medical Products Administration (NMPA) of China has approved sugemalimab for five indications:

• In combination with chemotherapy as first-line treatment of patients with metastatic squamous and non-squamous NSCLC with no EGFR or ALK genomic tumor aberrations and metastatic squamous NSCLC;
• For the treatment of patients with unresectable Stage III NSCLC whose disease has not progressed following concurrent or sequential platinum-based CRT;
• For the treatment of patients with relapsed or refractory extranodal NK/T-cell lymphoma;
• In combination with fluorouracil and platinum-based chemotherapy as first-line treatment of patients with unresectable locally advanced, recurrent or metastatic ESCC; and
• In combination with fluoropyrimidine- and platinum-containing chemotherapy as first-line treatment for unresectable locally advanced or metastatic gastric or gastroesophageal junction (G/GEJ) adenocarcinoma with a PD-L1 expression CPS ≥5.

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.