Analysis of East Asia subgroup in Study 309/KEYNOTE-775: lenvatinib plus pembrolizumab versus treatment of physician's choice chemotherapy in patients with previously treated advanced or recurrent endometrial cancer.

OBJECTIVE: In the global phase 3 Study 309/KEYNOTE-775 (NCT03517449) at the first interim analysis, lenvatinib+pembrolizumab significantly improved progression-free survival (PFS), overall survival (OS), and objective response rate (ORR) versus treatment of physician's choice chemotherapy (TPC) in patients with previously treated advanced/recurrent endometrial cancer (EC). This exploratory analysis evaluated outcomes in patients enrolled in East Asia at the time of prespecified final analysis. METHODS: Women ≥18 years with histologically confirmed advanced, recurrent, or metastatic EC with progressive disease after 1 platinum-based chemotherapy (2 if 1 given in neoadjuvant/adjuvant setting) were enrolled. Patients were randomized 1:1 to lenvatinib 20 mg orally once daily plus pembrolizumab 200 mg intravenously every 3 weeks (≤35 cycles) or TPC (doxorubicin or paclitaxel). Primary endpoints were PFS per RECIST v1.1 by blinded independent central review and OS. No alpha was assigned for this subgroup analysis. RESULTS: Among 155 East Asian patients (lenvatinib+pembrolizumab, n=77; TPC, n=78), median follow-up time (data cutoff: March 1, 2022) was 34.3 (range, 25.1-43.0) months. Hazard ratios (HRs) with 95% confidence intervals (CIs) for PFS (lenvatinib+pembrolizumab vs. TPC) were 0.74 (0.49-1.10) and 0.64 (0.44-0.94) in the mismatch repair proficient (pMMR) and all-comer populations, respectively. HRs (95% CI) for OS were 0.68 (0.45-1.02) and 0.61 (0.41-0.90), respectively. ORRs were 36% with lenvatinib+pembrolizumab and 22% with TPC (pMMR) and 39% and 21%, respectively (all-comers). Treatment-related adverse events occurred in 97% and 96% (grade 3-5, 74% and 72%), respectively. CONCLUSION: Lenvatinib+pembrolizumab provided clinically meaningful benefit with manageable safety compared with TPC, supporting its use in East Asian patients with previously treated advanced/recurrent EC. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03517449.

Front-line chemoimmunotherapy for treating epithelial ovarian cancer: Part II promising results of phase 2 study of paclitaxel-carboplatin-oregovomab regimen.

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.