Senhwa Biosciences has announced a major milestone in its oncology pipeline: its first-in-class investigational drug Pidnarulex (CX-5461) will enter a Phase 1b clinical trial in combination with the globally recognized antibody-drug conjugate (ADC) Trastuzumab Deruxtecan (Enhertu). 

 

The study will target HER2-positive solid tumors and breast cancer patients, including those with HER2-low expression and metastatic breast cancer.

 

The trial, supported by the U.S. National Cancer Institute's NExT program—which funds multiple CX-5461 studies including combination strategies—marks the entry of CX-5461 into the fast-growing ADC market.

 

CX-5461 is “the world's first and most advanced G-quadruplex (G4) stabilizer in development,” showing promising activity in early-phase trials for breast cancer and other solid tumors, sponsored by SU2C-CCTG in Canada. Its combination with Enhertu is expected to “enhance treatment efficacy in HER2-low patients and offer new therapeutic possibilities.”

 

Enhertu, co-developed by AstraZeneca and Daiichi Sankyo, is “the first HER2-directed ADC approved for HER2-low and HER2-ultralow metastatic breast cancer.” The therapy uses a monoclonal antibody to deliver the chemotherapy payload Deruxtecan directly into tumor cells, maximizing cancer cell killing while minimizing harm to healthy tissue.

 

The global ADC market is projected to grow at a CAGR of 28.4%, reaching around USD 47 billion by 2029. Analysts say Senhwa’s strategy of combining CX-5461 with Enhertu positions the company to tap directly into this fast-expanding oncology market.

 

Experts note that while HER2-targeted therapies have transformed breast and gastric cancer treatment, “their efficacy in HER2-low solid tumors remains limited.” They suggest that CX-5461’s novel mechanism of action, paired with ADC’s precise delivery platform, could “break through current treatment barriers, expand indications to additional tumor types, and establish a clear competitive edge.”

 

With global pharma racing into the ADC space, successful results could also attract strategic partnerships, licensing revenues, and long-term collaboration opportunities.

 

Analysts further highlight that advancing this trial could “significantly enhance Senhwa's international visibility in oncology, elevate the company's market valuation, and deliver sustainable long-term returns for investors and shareholders.”

 

By leveraging the combination of CX-5461 and Enhertu, Senhwa aims to “pioneer breakthrough therapies, capture a substantial share of the rapidly growing ADC market, and build a diverse oncology treatment platform.” 

 

The company reaffirmed its commitment to strengthening its R&D pipeline, integrating next-generation ADC technologies with proprietary drug candidates, and advancing toward its vision of becoming “a leading Asia-based oncology innovator with a global footprint.”