Senhwa Biosciences Inc. has announced a new clinical milestone as its first-in-class investigational drug Pidnarulex (CX-5461) is set to be evaluated in combination with the antibody-drug conjugate Trastuzumab Deruxtecan (Enhertu®) in a Phase 1b clinical trial.
The study will focus on patients with HER2-positive solid tumors and breast cancer, including those with HER2-low expression and metastatic breast cancer, and will be conducted with support from the US National Cancer Institute’s NExT program, which is funding multiple CX-5461 studies, including combination strategies.
The announcement follows Senhwa’s recent clinical collaboration with BeOne Medicines to explore CX-5461 in combination with a marketed PD-1 inhibitor for the treatment of cold tumors, underscoring the company’s expanding combination-therapy strategy in oncology.
CX-5461 is the world’s first and most advanced G-quadruplex stabilizer in clinical development and has demonstrated encouraging activity in early-phase trials for breast cancer and other solid tumors in studies sponsored by SU2C-CCTG in Canada. Its evaluation alongside Enhertu® marks CX-5461’s entry into the rapidly expanding ADC space. Enhertu®, co-developed by AstraZeneca and Daiichi Sankyo, is the first HER2-directed ADC approved for HER2-low and HER2-ultralow metastatic breast cancer and works by using a monoclonal antibody to selectively target tumor cells and deliver the chemotherapy payload deruxtecan directly to the cancer, improving tumor cell killing while limiting damage to healthy tissue.
The global ADC market is projected to grow at a compound annual growth rate of 28.4 percent to reach approximately USD 47 billion by 2029, and analysts note that Senhwa’s strategy of combining CX-5461 with a leading ADC positions the company to participate directly in this high-growth oncology segment.
While existing HER2-targeted therapies have significantly improved outcomes in breast and gastric cancers, their effectiveness in HER2-low solid tumors remains limited, and experts suggest that the novel mechanism of CX-5461, when paired with the targeted delivery of an ADC, could overcome current treatment limitations, expand indications across additional tumor types, and create a differentiated competitive advantage.
With global pharmaceutical companies accelerating investment in the ADC field, licensing deals and strategic collaborations have become increasingly common. Market observers indicate that strong clinical results from the CX-5461 and Enhertu® combination could attract partnerships with major international pharmaceutical players, generating meaningful licensing revenue and long-term collaboration opportunities.
Analysts further believe that successful advancement of the trial would enhance Senhwa’s international profile in oncology, strengthen its valuation, and support sustained long-term value creation for investors.
HER2 is widely recognized as a key oncogenic driver across multiple tumor types, and Senhwa aims to leverage the combination of CX-5461 and Enhertu® to develop breakthrough therapies, secure a meaningful position in the fast-growing ADC market, and build a diversified oncology treatment platform.
