Rapid Advancement Across Core R&D Pipeline

• The global, multicenter Phase I/II clinical trial of CS2009 (PD-1/VEGF/CTLA-4 trispecific antibody) is actively enrolling patients in Australia and China, and the Phase II IND application has been approved in the US. CS2009 demonstrates an excellent safety profile with a ≥Grade 3 TRAE rate of 23%, along with broad-spectrum anti-tumor activity. Notably, monotherapy data in lung cancer are encouraging: in first-line NSCLC patients with PD-L1 TPS ≥50%, the ORR reached 90% with a DCR of 100%, while the ORR was 25% in IO-pretreated NSCLC (AGA-negative). Furthermore, significant benefits were observed in patients with heavily pre-treated "cold tumors," achieving an ORR of 40% in non-clear cell renal cell carcinoma (nccRCC) and 33.3% in soft tissue sarcoma (STS).

• The global Phase Ib multicenter trial of CS5001 (ROR1 ADC) is being advanced rapidly and efficiently in Australia and China, with its R&D progress ranking among the top two globally. In combination with R-CHOP as a first-line treatment for DLBCL (at doses of 50–90 μg/kg), the CR rate exceeds 90%, and the ORR reaches 100%. Additionally, the combination cohort for later-line DLBCL has also shown favorable safety and a high ORR.

Continued Expansion of Global Commercialization Footprint

• Since 2025, sugemalimab has secured two new strategic partnerships and received approvals for two additional indications. Its global commercialization footprint now spans over 60 countries and regions, with further collaborations and regulatory filings actively underway.

Breakthroughs in Local Manufacturing and Reimbursement Access

• GAVRETO^® (pralsetinib) successfully obtained approval for local manufacturing in China and was included in the National Reimbursement Drug List (NRDL) for the first time, positioning it for significant sales growth.

• The domestic supply of AYVAKIT^® (avapritinib) has officially commenced, complementing its successful NRDL renewal at the end of last year.

Emerging Preclinical Innovation Pipeline

• Three internally developed next-generation ADC candidates—CS5007 (EGFR/HER3 ADC), CS5008 (SSTR2/DLL3 ADC), and CS5006 (ITGB4 ADC)—will present preclinical research findings at AACR 2026, with IND submissions planned for 2026.

Solid Financial Position

• Revenue was RMB269.6 million for the year ended December 31, 2025. The revenue from sales of pralsetinib decreased substantially, which is primarily due to price adjustments of pralsetinib made in preparation for the NRDL negotiation, along with related one-off channel compensation. Upon pralsetinib's inclusion in NRDL, the anticipated revenue ramp-up in 2026 and beyond is expected to outweigh the short-term negative impact on revenue in 2025. License fee income also decreased substantially, primarily due to the recognition of significant one-time upfront fees and milestone payments received in 2024.

• Cash and cash equivalents and time deposits were RMB918.7 million as of December 31, 2025.

SUZHOU, China, March 26, 2026 /PRNewswire/ -- CStone Pharmaceuticals ("CStone," HKEX: 2616), an innovation-driven biopharmaceutical company focused on the research and development of therapies for oncology, immunology, inflammation, and other key disease areas, today announced its 2025 annual results and recent business highlights.

Dr. Jason Yang, CEO, President of R&D, and Executive Director at CStone, stated, "2025 represents a pivotal strategic inflection point for CStone as we advance our Pipeline 2.0 and accelerate our commercial transformation. Over the past year, we have made highly efficient progress across our innovative pipeline, with our core asset, CS2009, demonstrating compelling efficacy in the latest clinical data. We are on track to initiate multiple global multi-regional Phase III trials by the end of 2026, reinforcing its potential as a next-generation immuno-oncology backbone.

On the commercial front, we continued to expand the global footprint of sugemalimab, while achieving important milestones in China for pralsetinib and avapritinib, including localization and reimbursement access. These efforts have reignited growth momentum in the China market and strengthened the foundation of our commercial platform.

Importantly, while driving business growth, we have maintained a solid financial position, with a cash balance of RMB 918.7 million as of the end of 2025. This financial strength enables us to continue investing in innovation while ensuring disciplined and sustainable operations.

Looking ahead, we remain committed to maximizing the commercial value of our established products while advancing our Pipeline 2.0 with focus and discipline. Through continued innovation and execution, we aim to drive long-term value creation and deliver sustainable returns for our shareholders."

Business Highlights

For the year ended December 31, 2025, and up to the date of this results announcement, we advanced our innovative pipeline and maximized the commercial value of our in-market assets. Our Pipeline 2.0 achieved significant progress, highlighted by the clinical program CS2009 advancing to Phase II and delivering the first global clinical data for a PD-1/VEGF/CTLA-4 trispecific antibody. We also expanded our therapeutic focus into autoimmune and inflammatory diseases. Commercially, we secured two international agreements for the global commercialization of sugemalimab and obtained regulatory approvals in the European Union (EU) and United Kingdom (U.K.) for Stage III NSCLC. In China, AYVAKIT^® (avapritinib) was successfully renewed on the NDRL, while GAVRETO^® (pralsetinib) achieved its first-time inclusion. These accomplishments underscore our sustained commitment to developing innovative therapies for patients worldwide.

Clinical Stage Core Assets

CS2009, PD-1/VEGF/CTLA-4 trispecific antibody

• Global Phase II trial Ongoing

Patient enrollment is active in our global, multicenter Phase II trial. The first patient was dosed in Australia in September 2025. The IND application for this trial was approved by the China National Medical Products Administration (NMPA) in November 2025 and by the U.S. Food and Drug Administration (FDA) in February 2026. This multi-cohort, parallel expansion study is designed to evaluate the efficacy, safety, tolerability, and pharmacokinetics (PK)/Pharmacodynamics (PD) of CS2009 as monotherapy and in combination regimens in 15 cohorts across 9 solid tumor indications, including NSCLC, colorectal cancer (CRC), extensive-stage small cell lung cancer (ES-SCLC), cervical cancer (CC), gastric or gastroesophageal junction (G/GEJ) adenocarcinoma, esophageal squamous cell carcinoma (ESCC), platinum-resistant ovarian cancer (PROC), triple-negative breast cancer (TNBC), and hepatocellular carcinoma (HCC). Active patient enrollment is ongoing in Australia and China.

• First-in-class (FIC)/best-in-class (BIC) potential as next-generation I/O backbone

More than 100 late-line patients have been enrolled in Phase I trial. CS2009 has demonstrated a favorable safety and tolerability profile, with no dose-limiting toxicity (DLT) reported and maximum tolerated dose (MTD) not reached. As of the data cutoff of March 17, 2026 with a median follow-up of approximately 6 months. The more mature data continue to reinforce its favorable safety profile, with 23% incidence of Grade ≥3 Treatment-Related Adverse Events (TRAEs). No excessive toxicities related to CTLA-4 occurred, and the incidence of Grade ≥3 VEGF-related AEs was low.

CS2009 monotherapy demonstrates potent antitumor activity in later-line "cold" tumors that are not sensitive to PD-(L)1 mAb. An overall response rate (ORR) of 40% was observed in patients with nccRCC, and an ORR of 33.3% in STS, showcasing its broad-spectrum therapeutic potential across multiple tumor types.

Safety data from multiple cohorts of CS2009 combined with standard chemotherapy showed that the combinations were well-tolerated across tumor types, with CS2009 not increasing the incidence or severity of chemotherapy-related adverse events.

Compelling Efficacy has been observed in Lung Cancer. CS2009 monotherapy demonstrates encouraging Phase I/II efficacy in NSCLC. In first-line NSCLC (PD-L1 tumor proportion score [TPS]≥50%), the ORR reached 90%, with a DCR of 100%. In IO-pretreated, AGA negative second-/later-line NSCLC, ORR reached 25%.

• Efficient and Clearly-Defined Global Development Strategy

Additional Phase I and Phase II clinical data for CS2009 are expected to be presented at the 2026 American Society of Clinical Oncology (ASCO) Annual Meeting and/or the European Society for Medical Oncology (ESMO) Congress.

The company plans to initiate the first wave of Phase III global multi-regional clinical trials (MRCT) for CS2009 by the end of 2026, targeting indications including NSCLC, CRC, and ES-SCLC.

CS5001, ROR1 ADC

• Global Phase Ib enrollment ongoing

The global, multicenter Phase Ib clinical trial of CS5001 continues to advance patient enrollment across sites in Australia and China. The trial is designed to determine the recommended Phase II dose (RP2D) and further evaluate the safety, tolerability, PK, and efficacy of CS5001 as monotherapy and in combination with systemic therapies in nine cohorts of selected tumor types. Current enrollment is prioritizing combination cohorts with standard-of-care (SOC) regimens, including CS5001 in combination with R-CHOP (Rituximab + Cyclophosphamide + Doxorubicin + Vincristine + Prednisone) for first-line treatment of Diffuse Large B-Cell Lymphoma (DLBCL) and CS5001 in combination with other SOC therapies for front-line DLBCL. Monotherapy cohorts continue to enroll patients with aggressive and indolent advanced lymphomas. In parallel, CS5001 is being evaluated in advanced solid tumors, both as monotherapy and in combination with the anti-PD-L1 antibody sugemalimab.

• Promising efficacy and safety profile observed in front line DLBCL

When combined with R-CHOP in the first-line DLBCL setting, no DLTs were observed across the 50–90 μg/kg dose range, with an ORR of 100% and a complete response (CR) rate exceeding 90%. In later-line DLBCL, the combination with standard-of care therapies is currently undergoing dose finding, with no DLTs reported to date and a high ORR already observed.

Commercial Products

CEJEMLY^® (sugemalimab), anti-PD-L1 antibody

• Global expansion and regulatory approvals

Following sugemalimab's initial marketing authorization in the EU and U.K. for Stage IV NSCLC, the product received additional approvals in the EU in November 2025, and subsequently in the U.K. in February 2026, as monotherapy for adults with unresectable Stage III NSCLC whose disease has not progressed following platinum-based chemoradiotherapy (CRT). With these approvals, sugemalimab has become one of only two anti-PD-(L)1 antibodies approved in both the EU and U.K. for Stage III NSCLC, positioning it as a comprehensive therapy option spanning locally advanced, unresectable Stage III to metastatic Stage IV disease. Meanwhile, marketing authorization applications for sugemalimab have been either approved or are under active review in more than ten countries worldwide.

• Global commercialization driven by strategic alliances

In January 2025, we entered into a partnership with Laboratorios Stein S.A. (SteinCares) to commercialize sugemalimab across ten countries in Latin America (LATAM). This was followed by a partnership with Istituto Gentili S.R.L. (Gentili) in July 2025 to commercialize sugemalimab in 23 countries in Western Europe and the U.K. To date, four partnerships have been executed extending sugemalimab's international footprint to over 60 countries around the world. Additional partnerships in other markets are under discussion.

GAVRETO^® (pralsetinib), RET inhibitor

• Localized production approved

In July 2025, the China NMPA approved the manufacturing localization application for Pralsetinib Capsules (pralsetinib, 100 mg). In 2026, the supply in China will gradually transition from imported products to end-to-end domestic production – from active pharmaceutical ingredient to finished drug product – significantly enhancing cost efficiency and supply chain resilience.

• NRDL inclusion

In December 2025, GAVRETO^® (pralsetinib, 100 mg) was included for the first time in the latest NRDL released by China's National Healthcare Security Administration, which took effect on January 1, 2026.

AYVAKIT^® (avapritinib), KIT/PDGFRA inhibitor

• Domestic supply launched

Following the 2024 China NMPA approval for localization production, domestic supply of avapritinib tablets (300 mg and 100 mg) commenced in February 2025, driving anticipated gross margin expansion.

• NRDL renewal

Following its initial inclusion in December 2023, AYVAKIT^® was also successfully renewed on the NRDL in December 2025.

Preclinical/IND-enabling Stage Programs and Proprietary ADC platform

CStone's preclinical Pipeline 2.0 compromises over nine promising candidates across multispecific antibodies, antibody-drug conjugates (ADC) etc in oncology, immunology and inflammation diseases. We are dedicated to delivering clinical value through the development of these Pipeline 2.0 candidates, which will undergo international, multi-center clinical trials to maximize their global potential.

Our proprietary in-house ADC platform features optimized linkers for tumor-selective payload release and supports multiple Pipeline 2.0 ADC assets, including CS5007 (EGFR/HER3 bispecific ADC), CS5008 (DLL3/SSTR2 bispecific ADC), CS5006 (ITGB4 ADC), CS5009 (B7H3/PD-L1 bispecific ADC), etc.

In May 2025, we presented preclinical data for CS2009, CS5007, and CS5006 at the annual meeting of the American Association for Cancer Research (AACR).

Future and Outlook

Our mission is to deliver transformative therapies through scientific excellence and technological innovation, making high-quality treatments accessible worldwide to benefit patients and their families.

We reaffirm our commitment to advancing a robust and differentiated pipeline by prioritizing internal discovery capabilities and sustained R&D investments, while executing strategic partnerships to unlock the global value of our in-market products. Critical catalysts in 2026 include:

Clinical milestones

• Accelerate the clinical development of CS2009 and CS5001 while pursuing global partnerships to expedite development.
• Advance CS5007, CS5006, and other early-stage candidates into clinical stages.

Innovation and technology

• Strengthen proprietary platforms (e.g., ADC technology) to bolster our early preclinical pipeline.
• Present key clinical data at major conferences (e.g., ASCO and/or ESMO).

Financial Highlights

International Financial Reporting Standards (IFRS) Measures:

• Revenue was RMB269.6 million for the year ended December 31, 2025. The revenue is composed of RMB78.3 million from sales of pharmaceutical products (avapritinib, pralsetinib and sugemalimab), RMB167.7 million from license fee income and RMB23.6 million from royalty income of sugemalimab. (1) Revenue from sales of pralsetinib decreased substantially, which is primarily due to price adjustments of pralsetinib made in preparation for the NRDL negotiation, along with related one-off channel compensation. With pralsetinib's inclusion in the NRDL effective January 1, 2026, the anticipated revenue ramp-up in 2026 and beyond is expected to outweigh the short-term negative impact on revenue. (2) License fee income also decreased to some extent, primarily due to the recognition of significant one-time upfront fees and milestone payments received in 2024.
• Cost of revenue was RMB218.3 million for the year ended December 31, 2025, primarily due to inventory write-downs charged to cost of revenue and cost associated with an early billing of pralsetinib supply under the Patient Assistance Program covering the period through the first half of 2026 to mitigate customs clearance risks amid trade uncertainties.
• Research and development expenses were RMB311.5 million for the year ended December 31, 2025, primarily due to an increase in third party contracting costs for clinical trials, including the Phase I/II study for CS2009 and for research programs including CS5007's IND enabling studies.
• Administrative expenses were RMB89.0 million for the year ended December 31, 2025.
• Selling and marketing expenses were RMB83.3 million for the year ended December 31, 2025.
• Loss for the year was RMB437.0 million for the year ended December 31, 2025. Excluding a one-time negative impact of RMB146.9 million in total from channel compensation and inventory write-downs related to preparation for inclusion of pralsetinib in the NRDL, the loss was RMB290.1 million.
• Cash and cash equivalents and time deposits were RMB918.7 million as of December 31, 2025.

Non-International Financial Reporting Standards (Non-IFRS) Measures:

• Research and development expenses excluding the share-based payment expenses were RMB299.5 million for the year ended December 31, 2025, primarily due to an increase in third party contracting costs for clinical trials, including the Phase I/II study for CS2009 and for research programs including CS5007's IND enabling studies.
• Administrative and selling and marketing expenses excluding the share-based payment expenses were RMB160.4 million for the year ended December 31, 2025.
• Loss for the year excluding the share-based payment expenses was RMB413.0 million for the year ended December 31, 2025. Excluding both (1)share-based payment expenses of RMB24.0 million and (2) a one-time negative impact of RMB146.9 million in total from channel compensation and inventory write-downs related to preparation for inclusion of pralsetinib in the NRDL, the loss was RMB266.1 million.

2025 Annual Results Conference Call

The Company will host its 2025 annual results earnings call at 10:00 a.m. (Beijing Time) on Friday March 27, 2026. Please register for the conference in advance through the link: https://s.comein.cn/f79etaud.

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, immunology, 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 21 new drug applications covering 9 indications. The company's pipeline is balanced by 16 promising candidates, featuring 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. 

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.

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Source: CStone Pharmaceuticals Related Stocks: HongKong:2616