Faculty Bibliography

Mismatch repair-deficient (dMMR) endometrial cancer is an inflamed phenotype with poor outcomes when meeting high-risk criteria and limited treatment options in the adjuvant setting. We report protocol-prespecified subgroup analysis of patients with dMMR tumors from the phase 3 ENGOT-en11/GOG-3053/KEYNOTE-B21 study (NCT04634877) in newly-diagnosed, high-risk endometrial cancer after surgery with curative intent. Patients were randomized to pembrolizumab 200mg or placebo (6 cycles) plus carboplatin-paclitaxel (4-6 cycles) Q3W, then pembrolizumab 400mg or placebo Q6W (6 cycles), respectively. MMR status was a stratification factor. Patients received radiotherapy at investigator discretion. Investigator-assessed disease-free survival (DFS) was a primary endpoint. No formal hypothesis testing was performed for subgroup analysis. In the intention-to-treat population, 141 patients in the pembrolizumab arm and 140 in the placebo arm had dMMR tumors. At this interim analysis, hazard ratio for DFS favored pembrolizumab (0.31; 95%CI, 0.14-0.69); median DFS was not reached in either group. Two-year DFS rates were 92.4% (95%CI, 84.4%-96.4%) and 80.2% (95%CI, 70.8%-86.9%), respectively. No new safety signals occurred. Longer-term follow-up of outcomes will be evaluated at final analysis. Preplanned subgroup analysis based on the study's stratification factors suggests that pembrolizumab plus chemotherapy improves DFS and is clinically relevant for patients with dMMR tumors in the curative-intent setting.

BACKGROUND:The phase III PRIMA/ENGOT-OV26/GOG-3012 trial met its primary endpoint. Niraparib first-line maintenance significantly prolonged progression-free survival (PFS) among patients with newly diagnosed advanced ovarian cancer that responded to first-line platinum-based chemotherapy, regardless of homologous recombination deficiency (HRD) status. Final overall survival (OS) results are reported. PATIENTS AND METHODS/METHODS:Patients were randomized 2:1 to niraparib or placebo, stratified by response to first-line treatment, receipt of neoadjuvant chemotherapy, and tumor HRD status. After reaching 60% target maturity, OS was evaluated via a stratified log-rank test using randomization stratification factors and summarized using Kaplan-Meier methodology. OS testing was hierarchical [overall population first, then the homologous recombination-deficient (HRd) population]. Other secondary outcomes and long-term safety were assessed; an updated, ad hoc analysis of investigator-assessed PFS was also conducted (cut-off date, 8 April 2024). RESULTS:The median follow-up was 73.9 months. In the overall population, the OS hazard ratio was 1.01 [95% confidence interval (CI) 0.84-1.23; P = 0.8834] for niraparib (n = 487) versus placebo (n = 246). In the HRd (n = 373) and homologous recombination-proficient (n = 249) populations, the OS hazard ratios were 0.95 (95% CI 0.70-1.29) and 0.93 (95% CI 0.69-1.26), respectively. Subsequent poly(ADP-ribose) polymerase inhibitor therapy was received by 11.7% and 15.8% of niraparib patients and 37.8% and 48.4% of placebo patients in the overall and HRd populations, respectively. The 5-year PFS rate numerically favored niraparib in the overall (niraparib, 22%; placebo, 12%) and HRd populations (niraparib, 35%; placebo, 16%). Myelodysplastic syndromes/acute myeloid leukemia incidence was <2.5% (niraparib, 2.3%; placebo, 1.6%). No new safety signals were observed. CONCLUSIONS:In patients with newly diagnosed advanced ovarian cancer at high risk of recurrence, there was no difference in OS between treatment arms. In the HRd population, patients alive at 5 years were two times as likely to be progression free with niraparib treatment than placebo. Long-term safety remained consistent with the established niraparib safety profile.

OBJECTIVES/OBJECTIVE:Patterns of disease recurrence on poly(ADP-ribose) polymerase inhibitor maintenance therapy are unclear and may affect subsequent treatment. This ad hoc subgroup analysis of the phase 3 PRIMA/ENGOT-OV26/GOG-3012 study evaluated patterns of initial recurrence in patients with advanced ovarian cancer (AOC). METHODS:PRIMA included participants at high risk for disease progression. This ad hoc analysis only evaluated participants randomized to niraparib maintenance without evidence of disease at baseline. The number and site(s) of initial recurrent lesions at investigator-assessed progressive disease (PD) were evaluated. RESULTS:Of the 314 niraparib-treated patients analyzed, 190 developed ≥1 new lesion (median number of new lesions, 1.0; interquartile range, 1-2). In total, 93.2% (177/190) of patients developed 1-3 lesions at first disease progression. The most common sites of recurrence were the peritoneum (30.0% [57/190]), lymph nodes (26.3% [50/190]), and liver (20.5% [39/190]). Similar results were observed when patients with PD were stratified by biomarker status, disease stage at diagnosis, and type of debulking surgery. Patients with homologous recombination-proficient tumors, stage III disease, or a history of primary debulking developed a median of 2.0 new lesions at first progression; patients with homologous recombination-deficient tumors, stage IV disease, or a history of interval debulking developed a median of 1.0 new lesion. CONCLUSIONS:Many patients with AOC without lesions at first-line maintenance treatment initiation develop oligometastatic disease at first recurrence. Prospective evaluation is required to determine whether these patients have improved outcomes when local therapies are combined with continuous, systemic, targeted maintenance therapy.

The Gynecologic Cancer InterGroup (GCIG) Endometrial Cancer Consensus Conference on Clinical Research (ECCC) was held in Incheon, South Korea, Nov 2-3, 2023. The aims were to develop consensus statements for future trials in endometrial cancer to achieve harmonisation on design elements, select important questions, and identify unmet needs. All 33 GCIG member groups participated in the development, refinement, and finalisation of 18 statements within four topic groups, addressing adjuvant treatment in high-risk disease; treatment for metastatic and recurrent disease; trial designs for rare endometrial cancer subgroups and special circumstances; and specific methodology and adaptation for trials in low-resource settings. In addition, eight areas of unmet need were identified. This was the first GCIG Consensus Conference to include patient advocates and an expert on inclusion, diversity, equity, and access to take part in all aspects of the process and output. Four early-career investigators were also selected for participation, ensuring that they represented different GCIG member groups and regions. Unanimous consensus was obtained for 16 of the 18 statements, with 97% concordance for the remaining two. Using the described methodology from previous Ovarian Cancer Consensus Conferences, this conference did not require even one minority statement. The high acceptance rate following active involvement in the preparation, discussion, and refinement of the statements by all representatives confirmed the consensus progress within a global academic setting, and the expectation that the ECCC will lead to greater harmonisation, actualisation, inclusion, and resolution of unmet needs in clinical research for individuals living with and beyond endometrial cancer worldwide.

OBJECTIVE:To identify characteristics associated with long-term progression-free survival (≥2 years) in patients with advanced ovarian cancer treated with niraparib first-line maintenance therapy in the phase III PRIMA/ENGOT-OV26/GOG-3012 study. METHODS:/homologous recombination-deficiency status, residual disease status, and duration from end of chemotherapy to randomization. Logistic regression modeling using backward elimination (significance level=0.15) identified covariates associated with long-term progression-free survival (clinical cut-off date November 17, 2021). RESULTS:wild-type/homologous recombination-proficient/not determined tumors), FIGO stage III (vs IV), and 0 or 1 baseline non-target lesions (vs ≥2 baseline non-target lesions). CONCLUSIONS:mutation/homologous recombination-deficiency status, FIGO stage, and number of baseline non-target lesions may predict progression-free survival of ≥2 years in patients with advanced ovarian cancer receiving niraparib first-line maintenance therapy. TRIAL REGISTRATION NUMBER/BACKGROUND:NCT02655016.

BACKGROUND:We evaluated the feasibility of completing 6 cycles of nab-paclitaxel (nab-P) and carboplatin (C) in a single arm prospective clinical trial for advanced/recurrent EC and safety and efficacy of day (D) 1, 8 nab-P in combination with D1 C q3weeks. METHODS:IV q21D. The trial tested the null hypothesis that subjects completing 6 cycles was ≤0.50 versus the alternative that the proportion is ≥0.75 in a single stage design with alpha = 0.05 and power = 80% with 23 subjects. Patients who completed 6 cycles (primary outcome), objective response rate (ORR) and clinical benefit rate (CBR) were estimated with exact 95% Clopper-Pearson confidence intervals. Progression free survival (PFS) and overall survival (OS) were estimated using Kaplan-Meier methods. RESULTS:From 08/2016-03/2018, 23 patients were enrolled. Nineteen patients (82.6%, 95% CI: 61.2%, 95.0%) completed 6 cycles, thus we could reject our null. Twelve patients (52.2%) experienced ≥1 grade 3/4 treatment-related adverse events including: anemia, 6 (26.1%); neutropenia, 5 (21.7%); diarrhea, 3 (13.0%). Fourteen patients (60.1%) reported grade 1 neuropathy. Of 9 patients with measurable target lesions, the ORR was 33.3% (95% CI: 7.5%, 70.1%) and CBR was 55.6% (95% CI: 21.2%, 86.3%). Median PFS in the advanced/recurrent patients was 23.2 (95% CI: 12.1, NR) months. CONCLUSIONS:The nab-P/C D1, 8 regimen met pre-specified feasibility criteria with acceptable toxicity and efficacy. Use of nab-P decreases need for steroid pre-medications, and this carboplatin doublet may prove advantageous for trials assessing combinations with immune checkpoint inhibitors in advanced EC.

BACKGROUND:Part 1 of the RUBY trial (NCT03981796) evaluated dostarlimab plus carboplatin-paclitaxel compared with placebo plus carboplatin-paclitaxel in patients with primary advanced or recurrent endometrial cancer. At the first interim analysis, the trial met one of its dual-primary endpoints with statistically significant progression-free survival benefits in the mismatch repair deficient/microsatellite instability-high (dMMR/MSI-H) and overall populations. Overall survival (OS) results are reported from the second interim analysis. PATIENTS AND METHODS/METHODS:RUBY is a phase 3, global, double-blind, randomized, placebo-controlled trial. Part 1 of RUBY enrolled eligible patients with primary advanced stage III or IV or first recurrent endometrial cancer who were randomly assigned (1:1) to receive either dostarlimab (500 mg) or placebo, plus carboplatin-paclitaxel every 3 weeks for 6 cycles followed by dostarlimab (1000 mg) or placebo every 6 weeks for up to 3 years. OS was a dual-primary endpoint. RESULTS:A total of 494 patients were randomized (245 in dostarlimab arm; 249 in placebo arm). In the overall population, with 51% maturity, RUBY met the dual-primary endpoint for OS at this second interim analysis, with a statistically significant reduction in the risk of death (HR = 0.69; 95% CI, 0.54-0.89; P = 0.0020) in patients treated with dostarlimab plus carboplatin-paclitaxel versus carboplatin-paclitaxel alone. The risk of death was lower in the dMMR/MSI-H population (HR = 0.32; 95% CI, 0.17-0.63; nominal P = 0.0002) and a trend in favor of dostarlimab was seen in the mismatch repair proficient/microsatellite stable (MMRp/MSS) population (HR = 0.79; 95% CI, 0.60-1.04; nominal P = 0.0493). The safety profile for dostarlimab plus carboplatin-paclitaxel was consistent with the first interim analysis. CONCLUSIONS:Dostarlimab in combination with carboplatin-paclitaxel demonstrated a statistically significant and clinically meaningful overall survival benefit in the overall population of patients with primary advanced or recurrent endometrial cancer while demonstrating an acceptable safety profile.