RemeGen Co. Ltd. recently gave an oral presentation on an interim analysis of the evaluation of the Company's proprietary Disitamab Vedotin (RC48), an investigational anti-HER2 antibody-drug conjugate (ADC) targeting prevalent solid tumor cancers with significant unmet medical needs, at the European Congress on Gynaecological Oncology (ESGO 2024 Congress) held in Barcelona from March 7-10, 2024. A Phase II, open-label, multicenter basket design study (NCT04965519) is currently underway to evaluate the effectiveness and safety of RC48 monotherapy in the treatment of HER2-expressing gynecologic malignancies.

The cervical cancer cohort includes patients with recurrent or metastatic cervical cancer who have progressed on at least 1L anti-tumor therapy and have HER2 IHC =1+. The treatment regimen consists of RC48 monotherapy administered at a dose of 2 mg/kg Q2W. The primary endpoint is objective response rate (ORR) by Independent Review Committee, with secondary endpoints including ORR by Investigator, duration of response (DoR), disease control rate (DCR), progression free survival (PFS), overall survival (OS), and safety.

As of October 31, 2023, 25 patients with cervical cancer were enrolled with a median age of 56 years (range: 35-66). Most patients (64%) had a baseline ECOG performance score of 1. 18 patients had a primary FIGO stage of IIB or higher. 16 (64%) patients had squamous cell carcinoma, and 9 (36%) had adenocarcinoma.

Among the 22 efficacy evaluable patients, The ORR was 36.4% (8/22). The confirmed ORR was 31.8% (7/22), the DCR was 86.4% (19/22), and the median time to response was 1.5 months. The mDoR was 5.52 months, and the mPFS was 4.37 months.

The most common treatment-related adverse events (TRAEs) included an increase in ALT (56%), an increase in AST (56%), and a decrease in white blood cell count (52%). Two patients (8%) experienced SAEs, and there were no deaths related to RC48. In conclusion, RC48 demonstrates a manageable safety profile and positive efficacy in HER2-expressing r/m cervical cancer patients, suggesting it to be a promising new treatment for HER2-expressed cervical cancer.

Cervical cancer is one of the most common gynecological malignancies, with the latest cancer report in China in 2022 showing the 5-year progression-free survival (PFS) rate of patients with late-stage recurrent or metastatic cervical cancer to be only about 15%. Current treatment options for patients with recurrent or metastatic cervical cancer are limited to immunotherapy and chemotherapy (ORR ranging from 14.6% to 26.8%), indicating there are significant unmet clinical needs.