This article was published by the team led by Director Wang Shanbing from the Oncology Center of Yibin Second People’s Hospital, revealing for the first time globally a rare phenomenon of liver “pseudoprogression” in patients with advanced cervical cancer following treatment with the novel Nectin-4 ADC (9MW2821). “Pseudoprogression” generally refers to the short-term enlargement of existing lesions or the appearance of new lesions during the initial phase of immunotherapy, without accompanying disease deterioration, followed by stabilization or shrinkage of the lesions in later stages. It is typically not true tumor progression.
The article reports on a patient with advanced metastatic cervical squamous cell carcinoma who had previously failed platinum-based chemotherapy and had not received immunotherapy. After just two cycles of treatment with 9MW2821, the patient’s baseline metastatic lesions significantly shrank, and the serum squamous cell carcinoma antigen (SCC) experienced a “cliff-like” drop—from 37.0 ng/mL plummeting to a completely normal 1.2 ng/mL (normal range ≤1.5). However, amid comprehensive improvement across multiple indicators, CT imaging unexpectedly revealed a “new low-density nodule” measuring 1.8 cm × 2.5 cm in the medial segment of the patient’s left liver lobe. A liver biopsy showed dense infiltration of lymphocytes, plasma cells, and neutrophils, with no granulomas, spindle cell proliferation, or viable tumor cells detected. The biopsy results ruled out disease progression, sarcoid-like reactions, or inflammatory pseudotumors. Considering the patient’s p16 positivity (high HPV viral antigenicity) and lack of immunotherapy history, Director Wang Shanbing’s team hypothesized that the antibody-drug conjugate targeted occult micrometastases, inducing immune cell death and releasing damage-associated molecular patterns, thereby triggering this intense inflammatory infiltration. The patient continued treatment, and subsequent imaging indicated gradual resolution of the liver lesion. Over a two-year follow-up, the liver lesion did not reappear.
ADC drugs are hailed as “magic bullets” for precisely targeting tumors. Previously, “pseudoprogression” was mostly observed in immunotherapies such as PD-1/PD-L1, and is considered “extremely rare” in ADC treatment for solid tumors. Director Wang Shanbing’s team’s finding holds significant guiding value for the clinical treatment of advanced cervical cancer. The article strongly emphasizes that one should not blindly discontinue potentially life-extending treatment due to imaging “illusions”, providing a reference for the clinical application of ADC drugs and effectively safeguarding the best therapeutic benefits for cancer patients.
9MW2821 is the world’s first innovative Nectin-4 ADC drug to enter Phase III clinical trials for the cervical cancer indication. Currently, enrollment for the Phase III monotherapy trial has been completed, with an interim analysis planned for the second half of 2026. Based on the interim analysis results, a pre-New Drug Application meeting with the NMPA CDE will be sought. The first-line combination therapy with toripalimab is in Phase II clinical development.
About Mabwell
Mabwell (688062.SH) is an innovative biopharmaceutical company with a full industry chain layout. Adhering to the vision of “Turning Innovation into Reality” and the mission of “Exploring Life, Benefiting Health,” the company is committed to providing patients with better efficacy and more accessible innovative biologics through original innovation, addressing unmet clinical needs globally. Since its establishment in 2017, Mabwell has built an innovation system covering the entire drug R&D cycle, starting from antibody drug target discovery and molecular discovery, through druggability research, preclinical research, clinical research, and production transformation, achieving a full industry chain layout integrating R&D, production, and marketing. The company focuses on oncology and age-related diseases, involving therapeutic areas such as oncology, autoimmune diseases, bone diseases, ophthalmology, hematology, and cardiovascular diseases. Leveraging internationally leading proprietary technology platforms and R&D innovation capabilities, Mabwell has established a rich and competitive pipeline. Currently, there are 15 key programs in preclinical, clinical, or marketing stages, including 11 innovative products and 4 biosimilars. Among these, 4 products have been launched, 1 is under marketing review, and 2 are in Phase III pivotal registration clinical trials. The company independently undertakes 1 national “Major New Drug Creation” major science and technology project, 2 national key R&D programs, and multiple provincial and municipal science and technology innovation projects. Mabwell prioritizes innovation and industrial transformation. Its antibody and recombinant protein drug industrialization base, compliant with China NMPA, US FDA, and EU EMA GMP standards, has been put into operation in Taizhou, Jiangsu, and has passed the EU QP audit. Large-scale commercial production bases in Jinshan, Shanghai, and Taizhou, Jiangsu, are under construction. For more information, please visit: www.mabwell.com.
Forward-Looking Statements
The information released in this press release may contain certain forward-looking statements. These statements inherently involve significant risks and uncertainties. When using terms such as “expect,” “believe,” “predict,” “anticipate,” “intend,” and other similar expressions, any reference to the company is intended to identify such forward-looking statements. The company is under no obligation to continuously update these forward-looking statements. These forward-looking statements are based on the current views, assumptions, expectations, estimates, predictions, and understanding of the company’s management regarding future events at the time the statements are made. These statements are not guarantees of future development and are subject to risks, uncertainties, and other factors, some of which are beyond the company’s control and difficult to predict. Therefore, actual results may differ materially from the information contained in the forward-looking statements due to future changes and developments in our business, competitive environment, and political, economic, legal, and social conditions. The company, its directors, employees, and agents assume no obligation to (a) correct or update any forward-looking statements contained on this website; and (b) any liability arising from any forward-looking statement not being realized or becoming inaccurate.