SAN FRANCISCO and SUZHOU, China, Oct. 25, 2026 /PRNewswire/ -- Innovent Biologics, Inc. (HKEX Stock Code: 01801), a biopharmaceutical company dedicated to the research, development, manufacturing, and commercialization of innovative drugs for major diseases including oncology, autoimmune, metabolic, and ophthalmic diseases, presented for the Phase 2 clinical data of its potential best-in-class IBI354 (HER2 ADC) as first-line treatment for breast cancer (BC) at the 2026 European Society for Medical Oncology (ESMO) Congress.

IBI354 has demonstrated encouraging antitumor activity and a highly favorable safety profile across multiple solid tumors. Two pivotal Phase 3 clinical studies (HeriCare-Ovarian01 and HeriCare-Breast01) have been initiated, which are expected to bring a next-generation ADC treatment option with high efficacy and low toxicity to ovarian cancer, breast cancer, and other tumor types. IBI354 also validates the differentiated advantages of Innovent's ADC technology platform and lay the foundation for the development of its next-generation bispecific ADCs and dual-payload ADCs.

1776P - IBI354 plus pertuzumab as first-line (1L) treatment for patients (pts) with HER2-positive, unresectable locally advanced or metastatic breast cancer (BC): Results from a phase 2 study 

This study was designed to evaluate the efficacy and safety of IBI354 in combination with pertuzumab in patients with HER2-positive, unresectable locally advanced, or metastatic breast cancer. As of July 1, a total of 20 patients were enrolled to receive IBI354 9mg/kg Q3W in combination with pertuzumab, with a median follow-up of 9.6 months (range: 9–11) and a median treatment duration of 42.21 weeks (range: 24.1–49.0).

IBI354 in combination with pertuzumab demonstrated encouraging efficacy signals.
In patients receiving first-line treatment for HER2-positive breast cancer, the confirmed objective response rate (cORR) and disease control rate (DCR) were 95% and 100%, respectively. The median follow-up for progression-free survival (PFS) was 8.3 months. Both PFS and OS were not yet mature, with only 1 PFS event and no OS events.

IBI354 in combination with pertuzumab demonstrated a favorable safety profile.
The most common treatment-emergent adverse events (TEAEs) were nausea, vomiting, and anemia. No interstitial lung disease (ILD) occurred. Overall, 4 patients (20%) experienced Grade ≥3 treatment-related adverse events (TRAEs), 2 patients (10%) had dose interruptions due to TRAEs, no patients had dose reductions due to TRAEs, 1 patient (5%) discontinued treatment due to a TRAE, and no TRAE led to death.

Professor Xiaohua Zeng of Chongqing University Cancer Hospital stated: "HER2-positive advanced breast cancer is an important research direction in the field of precision treatment for breast cancer. In recent years, with the continuous development of anti-HER2 therapies and ADC drugs, patients have increasingly rich treatment options, and clinical outcomes have been significantly improved. At the same time, however, we should recognize that the treatment of advanced breast cancer is a long-term management endeavor. How to further optimize safety and improve patient tolerance while ensuring antitumor efficacy remains a topic requiring continued exploration in clinical practice. IBI354 has shown a very favorable safety profile, with no severe interstitial lung disease or ocular toxicity commonly observed with other ADC drugs, and a cORR of 95%. I look forward to further research results that will validate the long-term benefits for patients treated with IBI354."

Dr. Hui Zhou, Chief R&D Officer (Oncology Pipeline) of Innovent Biologics, stated: "As ADCs continue to advance cancer treatment, we are expanding our ADC pipeline and strengthening our capabilities. The latest breast cancer data for IBI354 presented at this year's ESMO Congress add to the growing body of clinical evidence supporting its ongoing development. We have initiated a Phase 3 study evaluating IBI354 as a first-line treatment for HER2-positive advanced breast cancer, with additional Phase 3 studies being planned. Guided by unmet patient needs, we remain committed to advancing next-generation ADCs with the goal of delivering meaningful improvements in cancer care."

About IBI354

IBI354 is an innovative HER2-targeted antibody–drug conjugate developed using Innovent's proprietary SoloTx^® ADC platform. Based on this platform, Innovent is promoting clinical trial studies multiple self-developed ADC molecules, which have shown promising safety and efficacy signals.

With a drug-to-antibody ratio (DAR) of 8, IBI354 delivers a high payload of effective drugs to tumors. The highly hydrophilic linker design contributes to its excellent biophysical and pharmacokinetic (PK) properties, while the hydrophobic payload enhances its bystander effect, targeting adjacent antigen-low or negative tumor cells. IBI354 exhibits extremely low exposure of free toxin in circulation and has an ideal safety profile based on pre-clinical and clinical studies. IBI354 has demonstrated remarkable anti-tumor activity in various tumor-bearing mice models, particularly in those resistant to HER2-targeted therapies and in metastatic tumors.

Starting from the urgent clinical needs, in addition to the Phase 3 studies (HeriCare-Breast01 and HeriCare-Ovarian01) already initiated in BC and PROC, Innovent will explore IBI354 in multiple solid tumor indications including adjuvant therapy and neoadjuvant therapy for BC.

About Innovent

Innovent is a leading biopharmaceutical company founded in 2011 with the mission to empower patients worldwide with affordable, high-quality biopharmaceuticals. The company discovers, develops, manufactures and commercializes innovative medicines that target some of the most intractable diseases. Its pioneering therapies treat cancer, cardiovascular and metabolic, autoimmune and eye diseases. Innovent has launched 20 products in the market. It has 1 asset under NDA review, 5 assets in phase 3 or pivotal clinical trials, and 20 more molecules in early clinical stage.

Innovent has entered into more than 30 strategic partnerships with global players such as Eli Lilly, Roche, Takeda, Pfizer, Sanofi, Incyte, and MD Anderson Cancer Center, representing an aggregate value of over RMB 350 billion. These efforts have set a benchmark for the high-quality outbound internationalization of China's innovative drug industry.

Guided by the motto, "Start with Integrity, Succeed through Action," Innovent maintains the highest standard of industry practices and works collaboratively to advance the biopharmaceutical industry so that first-rate pharmaceutical drugs can become widely accessible.

For more information, visit www.innoventbio.com, or follow Innovent on Facebook and LinkedIn.

Forward-Looking Statements

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These forward-looking statements are based on the existing beliefs, assumptions, expectations, estimates, projections and understandings of the management of Innovent with respect to future events at the time these statements are made. These statements are not a guarantee of future developments and are subject to risks, uncertainties and other factors, some of which are beyond Innovent's control and are difficult to predict. Consequently, actual results may differ materially from information contained in the forward-looking statements as a result of future changes or developments in our business, Innovent's competitive environment and political, economic, legal and social conditions.