CS5007 / CStone Pharma - LARVOL DELTA

China's National Medical Products Administration (NMPA) has cleared CStone Pharmaceuticals (HKEX: 2616) to begin clinical trials of CS5007, an EGFR/HER3 bispecific antibody-drug conjugate (ADC), in patients with advanced solid tumors. (AllSci Corp) - "The global Phase I first-in-human study is evaluating CS5007 monotherapy in patients with advanced solid tumors that have progressed following, or are ineligible for, standard treatment. The dose-escalation and expansion study will assess safety, tolerability, pharmacokinetics, pharmacodynamics, and preliminary antitumor activity, while establishing a recommended Phase II dose. Approximately 310 patients are expected to enroll across Australia and China."

First-in-human • Trial status • Solid Tumor

A Phase I Study of CS5007 in Participants With Advanced Solid Tumors (clinicaltrials.gov) - P1 | N=310 | Recruiting | Sponsor: CStone Pharmaceuticals | Not yet recruiting ➔ Recruiting

Enrollment open • First-in-human • Oncology • Solid Tumor

CStone Pharmaceuticals…announced that the global multicenter Phase I clinical trial of its Pipeline 2.0 core candidate CS5007 (an EGFR/HER3 bispecific antibody-drug conjugate [ADC]) has received ethics approval from the Australian Human Research Ethics Committee (HREC) (CStone Pharma Press Release) - "The newly initiated global, multicenter Phase I clinical trial is a first-in-human study comprising dose-escalation and dose-expansion cohorts evaluating CS5007 monotherapy in patients with advanced solid tumors whose disease has progressed following standard therapies, who are ineligible for standard treatment, or for whom no effective treatment options are available....Approximately 310 patients are expected to be enrolled. The trial is being conducted concurrently in Australia and China to accelerate its global development."

Trial status • Solid Tumor

A Phase I Study of CS5007 in Participants With Advanced Solid Tumors (clinicaltrials.gov) - P1 | N=310 | Not yet recruiting | Sponsor: CStone Pharmaceuticals

First-in-human • New P1 trial • Oncology • Solid Tumor

Preclinical efficacy and safety of CS5007, an EGFR×HER3 dual-targeting antibody-drug conjugate with a topoisomerase 1 inhibitor payload (AACR 2026) - "It also showed superior in vitro cytotoxicity over a bispecific control ADC (BL-B01D1 analog) and monospecific EGFR- or HER3-targeting ADCs in various tumor cell lines, including an osimertinib-resistant NSCLC model. With demonstrated enhanced signaling inhibition, superior efficacy across multiple solid tumor models, and a favorable safety margin in preclinical studies, CS5007 is planned for an IND submission in early 2026 to support clinical development in advanced solid tumors."

ADC • Preclinical • Lung Cancer • Non Small Cell Lung Cancer • Oncology • Solid Tumor

CS5007 - EGFR/HER3 Bispecific ADC (PRNewswire) - "CStone presented preclinical data...at AACR 2026....CS5007 exhibits potent, nanomolar-level, antigen-dependent cell-killing activity across a broad spectrum of tumor cell lines, including non-small cell lung cancer (NSCLC), squamous cell carcinoma (SCC), colorectal cancer (CRC), squamous cell carcinoma (SCCHN), pancreatic cancer (PANC), and breast cancer (BC)....CS5007 inhibited tumor growth in cell line-derived xenograft (CDX) models derived from multiple tumor types, including NSCLC, CRC, BC, SCCHN, and SCC."

Preclinical • Breast Cancer • Colorectal Cancer • Non Small Cell Lung Cancer • Pancreatic Cancer • Squamous Cell Carcinoma • Squamous Cell Carcinoma of Head and Neck

Phase I Clinical Trial Plan (PRNewswire) - "CStone plans to initiate the Investigational New Drug (IND) application for CS5007 in the first half of 2026. The planned CS5007-101 study will be a monotherapy dose-escalation and expansion study designed to evaluate safety and recommended phase II dose (RP2D) in patients with advanced solid tumors. The study plans to enroll approximately 70 adult patients with advanced solid tumors who have progressed on or are ineligible for standard treatment or have no effective treatment options."

IND • New P1 trial • Solid Tumor

CS5007: A novel EGFR and HER3 dual-targeted antibody-drug conjugate (ADC) with potent antitumor activity in preclinical studies (AACR 2025) - "For instance, MRG003, an EGFR-targeted ADC, has shown encouraging clinical outcomes in NPC and HNSCC...Daiichi's HER3-ADC, U3-1402, has shown promising clinical results in advanced EGFR-mutant NSCLC, confirming HER3 as a valid therapeutic target for ADC. Additionally, BL-B01D1, an EGFR/HER3 bispecific ADC, has shown encouraging phase 1 data in advanced cancers... CS5007 is a promising dual-targeted ADC that demonstrates potent antitumor efficacy with a favorable safety and PK profile. These preclinical findings support its further IND-enabling studies and clinical investigations for the treatment of various advanced solid tumors."

ADC • Preclinical • Colorectal Cancer • Head and Neck Cancer • Lung Cancer • Non Small Cell Lung Cancer • Oncology • Solid Tumor • Squamous Cell Carcinoma • Squamous Cell Carcinoma of Head and Neck • ERBB3

AACR 2026 Preview: CStone to Present Preclinical Data for Three Proprietary Pipeline Assets (CStone Pharma Press Release)

Preclinical • Neuroendocrine Tumor • Small Cell Lung Cancer

CStone Presents Preclinical Results of…CS5007 (EGFR/HER3 bispecific ADC)…at 2025 AACR (PRNewswire) - "Key Highlights:...CS5007 demonstrated high-affinity binding to EGFR single-positive, HER3 single-positive, and EGFR/HER3 double-positive tumor cells. CS5007 triggered high-rate internalization on tumor cells. CS5007 demonstrated potent, antigen-dependent cytotoxicity against tumor cells in vitro across varying EGFR and HER3 expression levels and showed robust tumor-growth inhibition in CDX models."

Preclinical • Solid Tumor

CS5007: A novel EGFR and HER3 dual-targeted antibody-drug conjugate (ADC) with potent antitumor activity in preclinical studies (PRNewswire) - "CStone to showcase...latest research achievements at AACR 2025....Abstract Number: 2954....Key Findings: CS5007 (EGFR/HER3 ADC) inhibited tumor growth by blocking downstream EGFR/HER3 signaling and releasing chemotherapeutic molecules in a target-dependent manner. Its lead compound demonstrated favorable stability and a PK profile comparable to those of monoclonal antibodies."

Preclinical • Oncology

CStone Reports 2024 Interim Results and Recent Corporate Updates (PRNewswire) - "Anticipated near-term catalysts include:...(i) CS2009: IND submissions expected in 2024/2025; (ii) CS5006: IND submission expected in 2025; (iii) CS5005: IND submission expected in 2025; (iv) CS2011/CS5007: IND submission expected in 2025."

IND • Solid Tumor