Taiwanese Journal of Obstetrics & Gynecology (Jan 2024)
Front-line chemoimmunotherapy for treating epithelial ovarian cancer: Part II promising results of phase 2 study of paclitaxel-carboplatin-oregovomab regimen
Abstract
In the Part I, we have discussed the background of CA125 and the development of anti-CA125 monoclonal antibody (MAb) to highlight the potential role of CA125 and anti-CA125 MAb in the management of women with advanced stage epithelial ovarian cancer (EOC). Glycosylation change either by N-link or by O-link of CA125 is supposed to play a role in the modification of immunity. Anti-CA125 MAb, which can be classified as OC 125-like Abs, M11-like Abs, and OV197-like Abs, is often used for diagnosing, screening, monitoring and detecting the mesothelin-related diseases of the abdominal cavity, particular for those women with EOC. Additionally, anti-CA125 MAb also plays a therapeutic role, named as OvaRex MAb-B43.13 (oregovomab), which has also been extensively reviewed in the Part I review article. The main mechanisms include (a) forming CA125 immune complexes to activate the antigen-presenting cells; (b) triggering induction of CA125-specific immune responses, including anti-CA125 Abs against various epitopes and CA125-specific B and T cell responses; and (c) triggering CD4 and CD8 T-cell responses specific for B43.13 to produce specific and non-specific immune response. With success in vitro, in vivo and in primitive studies, phase II study was conducted to test the effectiveness of chemoimmunotherapy (CIT) for the management of EOC patients. In the 97 EOC patients after optimal debulking surgery (residual tumor <1 cm or no gross residual tumor), patients treated with CIT had a dramatical and statistically significant improvement of both progression-free survival (PFS) and overall survival (OS) compared to those treated with chemotherapy alone with a median PFS of 41.8 months versus 12.2 months (hazard ratio [HR] 0.46, 95 % confidence interval [CI] 0.28–0.7) and OS not yet been reached (NE) versus 42.3 months (HR 0.35, 95 % CI 0.16–0.74), respectively. The current review as Part II will explore the possibility of using CIT as front-line therapy in the management of advanced-stage EOC patients after maximal cytoreductive surgery based on the evidence by many phase 2 studies.
