Management of endometrial cancer in Latin America: raising the standard of care and optimizing outcomes

Molecular characterization of endometrial cancer is allowing for increased understanding of the natural history of tumors and paving a more solid pathway for novel therapies. It is becoming increasingly apparent that molecular classification is superior to histological classification in terms of reproducibility and prognostic discrimination. In particular, the Proactive Molecular Risk Classifier for Endometrial Cancer allows classification of endometrial cancer into groups very close to those determined by the Cancer Genome Atlas Research Network-that is, DNA polymerase epsilon-mutated, mismatch repair-deficient, p53 abnormal, and non-specific molecular profile tumors. The transition from the chemotherapy era to the age of targeted agents and immunotherapy, which started later in endometrial cancer than in many other tumor types, requires widespread availability of specialized pathology and access to novel agents. Likewise, surgical expertise and state-of-the-art radiotherapy modalities are required to ensure adequate care. Nevertheless, Latin American countries still face considerable barriers to implementation of international guidelines. As we witness the dawn of precision medicine as applied to endometrial cancer, we must make continued efforts towards improving the quality of care in this region. The current article discusses some of these challenges and possible solutions.

Adding immunotherapy to first-line treatment of advanced and metastatic endometrial cancer

BACKGROUND

Immunotherapy has transformed the endometrial cancer treatment landscape, particularly for those exhibiting mismatch repair deficiency [MMRd/microsatellite instability-hypermutated (MSI-H)]. A growing body of evidence supports the integration of immunotherapy with chemotherapy as a first-line treatment strategy. Recently, findings from ongoing trials such as RUBY (NCT03981796), NRG-GY018 (NCT03914612), AtTEnd (NCT03603184), and DUO-E (NCT04269200) have been disclosed.

MATERIALS AND METHODS

This paper constitutes a review and meta-analysis of phase III trials investigating the role of immunotherapy in the first-line setting for advanced or recurrent endometrial cancer.

RESULTS

The pooled data from 2320 patients across these trials substantiate the adoption of chemotherapy alongside immunotherapy, revealing a significant improvement in progression-free survival compared to chemotherapy alone [hazard ratio (HR) 0.70, 95% confidence interval (CI) 0.62-0.79] across all patient groups. Progression-free survival benefits are more pronounced in MMRd/MSI-H tumors (n = 563; HR 0.33, 95% CI 0.23-0.43). This benefit, albeit less robust, persists in the MMR-proficient/microsatellite stable group (n = 1757; HR 0.74, 95% CI 0.60-0.91). Pooled data further indicate that chemotherapy plus immunotherapy enhances overall survival compared to chemotherapy alone in all patients (HR 0.75, 95% CI 0.63-0.89). However, overall survival data maturity remains low.

CONCLUSIONS

The incorporation of immunotherapy into the initial treatment for advanced and metastatic endometrial cancer brings about a substantial improvement in oncologic outcomes, especially within the MMRd/MSI-H subset. This specific subgroup is currently a focal point of investigation for evaluating the potential of chemotherapy-free regimens. Ongoing exploratory analyses aim to identify non-responding patients eligible for inclusion in clinical trials.

Combining Homologous Recombination-Deficient Testing and Functional RAD51 Analysis Enhances the Prediction of Poly(ADP-Ribose) Polymerase Inhibitor Sensitivity

PURPOSE

To meet the urgent need for accessible homologous recombination-deficient (HRD) test options, we validated a laboratory-developed test (LDT) and a functional RAD51 assay to assess patients with ovarian cancer and predict the clinical benefit of poly(ADP-ribose) polymerase inhibitor therapy.

METHODS

Optimization of the LDT cutoff and validation on the basis of samples from 91 patients enrolled in the ENGOT-ov24/NSGO-AVANOVA1&2 trial (ClinicalTrials.gov identifier: NCT02354131), previously subjected to commercial CDx HRD testing (CDx). RAD51 foci analysis was performed and tumors with ≥five foci/nucleus were classified as RAD51-positive (homologous recombination-proficient).

RESULTS

The optimal LDT cutoff is 54. Comparing CDx genome instability score and LDT HRD scores show a Spearman's correlation of rho = 0.764 (P < .0001). Cross-tabulation analysis shows that the sensitivity of the LDT HRD score is 86% and of the LDT HRD status is 91.8% (Fisher's exact test P < .001). Survival analysis on progression-free survival (PFS) of LDT-assessed patients show a Cox regression P < .05. RAD51 assays show a correlation between low RAD51 foci detection (<20% RAD51+ cells) and significantly prolonged PFS (P < .001).

CONCLUSION

The robust concordance between the open standard LDT and the CDx, especially the correlation with PFS, warrants future validation and implementation of the open standard LDT for HRD testing in diagnostic settings.

Oral Selinexor as Maintenance Therapy After First-Line Chemotherapy for Advanced or Recurrent Endometrial Cancer

PURPOSE

Selinexor inhibits exportin-1 (XPO1) resulting in nuclear accumulation of tumor suppressor proteins including p53 and has clinical activity in endometrial cancer (EC). The primary end point was to assess progression-free survival (PFS) with once-weekly oral selinexor in patients with advanced or recurrent EC.

PATIENTS AND METHODS

ENGOT-EN5/GOG-3055/SIENDO was a randomized, prospective, multicenter, double-blind, placebo-controlled, phase III study at 107 sites in 10 countries. Patients 18 years or older with histologically confirmed EC were enrolled. All had completed a single line of at least 12 weeks of taxane-platinum combination chemotherapy and achieved partial or complete response. Patients were assigned to receive 80 mg oral selinexor once weekly or placebo with 2:1 random assignment (ClinicalTrials.gov identifier: NCT03555422).

RESULTS

Between January 2018 and December 2021, 263 patients were randomly assigned, with 174 allocated to selinexor and 89 to placebo. The median PFS was 5.7 months (95% CI, 3.81 to 9.20) with selinexor versus 3.8 months (95% CI, 3.68 to 7.39) with placebo (hazard ratio [HR], 0.76 [95% CI, 0.54 to 1.08]; two-sided P = .126), which did not meet the criteria for statistical significance in the intent-to-treat population. Incorrect chemotherapy response stratification data for 7 (2.7%) patients were identified. In a prespecified exploratory analysis of PFS in audited stratification data, PFS for selinexor met the threshold for statistical significance (HR, 0.71; 95% CI, 0.499 to 0.996; two-sided P = .049). Furthermore, patients with the TP53 wild-type (wt) EC had a median PFS of 13.7 and 3.7 months with selinexor and placebo. The most common grade 3 treatment-related adverse events were nausea (9%), neutropenia (9%), and thrombocytopenia (7%).

CONCLUSION

The significance level for PFS was only met in the audited analysis. However, a preliminary analysis of a prespecified exploratory subgroup of patients with TP53wt EC showed promising results with selinexor maintenance therapy.

The promise of combining CDK4/6 inhibition with hormonal therapy in the first-line treatment setting for metastatic or recurrent endometrial adenocarcinoma

Metastatic or recurrent endometrioid adenocarcinoma of the uterine corpus is often incurable with limited treatment options. First-line treatment often includes cytotoxic chemotherapy, which incurs significant toxicities for many patients. Endometrial cancer, specifically endometrioid cancer, is a hormone-sensitive disease and, while single-agent hormonal therapies have demonstrated clinical benefit, resistance to these agents often leads to the use of chemotherapy. There is a lack of approved endocrine treatment options in the metastatic setting for most recurrent endometrial cancers, representing an unmet clinical need. Emerging evidence suggests that hormonal therapy in combination with other targeted treatments, such as cyclin dependent kinase (CDK)4/6 inhibitors, is well tolerated and effective in select patient populations. We discuss the clinical evidence suggesting that the combination of CDK4/6 inhibitors and hormonal therapy has the potential to represent an important addition to the first-line treatment options for patients with low-grade advanced or recurrent endometrial cancer.

Evolving treatment paradigms in metastatic or recurrent low-grade endometrial cancer: When is hormonal-based therapy the preferred option?

Endometrial cancer is the most common gynecologic malignancy in developed countries, with increasing incidence and mortality rates worldwide. While most cases are successfully treated with surgery, first-line treatment options for metastatic or recurrent endometrial cancer involve significant toxicities. Imprecise classification of heterogeneous subgroups further complicates treatment decisions and interpretation of clinical trial results. Recent advances in molecular classification are guiding treatment decisions for metastatic or recurrent endometrial cancers. Integrating molecular characteristics with traditional clinicopathology can both reduce overtreatment or undertreatment and help guide the appropriate choice of therapies and effective design of future studies. Here we discuss the treatment of metastatic or recurrent low-grade endometrioid adenocarcinoma of the uterine corpus, which is distinct from high-grade tumors histologically, molecularly, and in treatment response.

Advances in the Management of Recurrent Cervical Cancer: State of the Art and Future Perspectives

PURPOSE OF REVIEW

This review aims to give an insight into the currently available options for recurrent/metastatic (R/M) cervical cancer (CC), along with the main future, potentially practice-changing perspectives in this field.

RECENT FINDINGS

Improvements in terms of tumor responses were observed with the use of immune checkpoints inhibitors (ICIs) in the previously treated CC population, followed by emerging striking data in terms of both antitumor activity and survival rates with the addition of the ICIs to platinum-based chemotherapy with or without bevacizumab in the first-line setting. Furthermore, the CC treatment landscape took another step forward in 2021 with the introduction of antibody-drug conjugates (ADCs) in the second-line setting, a highly targeted therapeutic strategy, which demonstrated to be a valid alternative option in the recurrent setting. R/M CC is a hard-to-treat disease. However, after several years of limited systemic therapeutic options for the recurrent setting, the year 2018 marked a turning point for R/M CC patients, with the introduction of immunotherapy in the treatment paradigm, which completely reshaped the therapeutic armamentarium of the disease. Besides, another valuable treatment option represented by ADCs demonstrated its efficacy in the recurrent setting, thus further widening the treatment landscape for those patients. Yet, the introduction of immunotherapy in the upfront setting brought along new issues to be addressed such as the emerging ICIs resistance and the following need for alternative options in the post-ICIs setting. Several innovative therapeutic strategies are under investigation in ongoing clinical trials, with the aim of overcoming ICIs resistance with the addition of immunomodulatory agents or bypassing the ICIs resistance with novel alternative drugs.

Molecular Results and Potential Biomarkers Identified from the Phase 3 MILO/ENGOT-ov11 Study of Binimetinib versus Physician Choice of Chemotherapy in Recurrent Low-Grade Serous Ovarian Cancer

PURPOSE

We present the results of a post hoc tumor tissue analysis from the phase 3 MILO/ENGOT-ov11 study (NCT01849874).

PATIENTS AND METHODS

Mutation/copy-number analysis was performed on tissue obtained pre-randomization. The Kaplan-Meier method was used to estimate progression-free survival (PFS). Unbiased univariate analysis, Cox regression, and binary logistic regression were used to test associations between mutation status and outcomes, including PFS and binary response by local RECIST 1.1.

RESULTS

MILO/ENGOT-ov11 enrolled 341 patients, ranging in age from 22 to 79, from June, 2013 to April, 2016. Patients were randomized 2:1 to binimetinib or physician's choice of chemotherapy (PCC). The most commonly altered gene was KRAS (33%). In 135 patients treated with binimetinib with response rate (RR) data, other detected MAPK pathway alterations included: NRAS (n = 11, 8.1%), BRAF V600E (n = 8, 5.9%), RAF1 (n = 2, 1.5%), and NF1 (n = 7, 5.2%). In those with and without MAPK pathway alterations, the RRs with binimetinib were 41% and 13%, respectively. PFS was significantly longer in patients with, compared with those without, MAPK pathway alterations treated with binimetinib [HR, 0.5; 95% confidence interval (CI) 0.31-0.79]. There was a nonsignificant trend toward PFS improvement in PCC-treated patients with MAPK pathway alterations compared with those without (HR, 0.82; 95% CI, 0.43-1.59).

CONCLUSIONS

Although this hypothesis-generating analysis is limited by multiple testing, higher RRs and longer PFS were seen in patients with low-grade serous ovarian cancer (LGSOC) treated with binimetinib, and to a lesser extent in those treated with PCC, who harbored MAPK pathway alterations. Somatic tumor testing should be routinely considered in patients with LGSOC and used as a future stratification factor.

A multi-method approach to selecting PRO-CTCAE symptoms for patient-reported outcome in women with endometrial or ovarian cancer undergoing chemotherapy

BACKGROUND

Women with endometrial or ovarian cancer experience a variety of symptoms during chemotherapy. Patient-Reported outcomes (PROs) can provide insight into the symptoms they experience. A PRO tool tailored to this patient population can help accurately monitor adverse events and manage symptoms. The objective of this study was to identify items in the National Cancer Institute's measurement system Patient-Reported Outcomes Version of the Common Terminology Criteria for Adverse Events (PRO-CTCAE®) appropriate for use in a PRO tool for a population of women with endometrial or ovarian cancer undergoing treatment with taxanes (paclitaxel or docetaxel) in combination with carboplatin.

METHODS

A two-phase, sequential multi-methods approach was applied. In phase one, a comprehensive literature search was done to map the toxicity of the applied chemotherapeutics and phase III clinical studies. Phase two, which comprised selecting the PRO-CTCAE items, included discussions with and feedback from a patient advisory board, an additional literature search, and focus group interviews with senior oncologists and specialized oncology nurses. A national expert panel facilitated both phases in terms of carefully select items from the PRO-CTCAE library.

RESULTS

Phase one identified 18 symptoms and phase two, three additional ones, leading to the inclusion of 21 PRO-CTCAE symptoms in the final PRO tool. Since PRO-CTCAE also contains one to three sub-questions on the frequency, severity, and interference with daily activities of symptoms, there were 44 potential items.

CONCLUSIONS

This study describes taking a multi-method approach to selecting items from the PRO-CTCAE library for use in a population of women with endometrial or ovarian cancer undergoing chemotherapy. By systematically combining diverse approaches, we carefully selected 21 clinically relevant symptoms covered by 44 items in the PRO-CTCAE library. Future studies should investigate the psychometric properties of this PRO tool for women with endometrial or ovarian cancer.

European Society of Gynaecological Oncology Guidelines for the Management of Patients with Vulvar Cancer - Update 2023

BACKGROUND

As part of its mission to improve the quality of care for women with gynecological cancers across Europe, the European Society of Gynaecological Oncology (ESGO) first published in 2017 evidence-based guidelines for the management of patients with vulvar cancer.

OBJECTIVE

To update the ESGO guidelines based on the new evidence addressing the management of vulvar cancer and to cover new topics in order to provide comprehensive guidelines on all relevant issues of diagnosis and treatment of vulvar cancer.

METHODS

The ESGO Council nominated an international development group comprised of practicing clinicians who provide care to vulvar cancer patients and have demonstrated leadership through their expertize in clinical care and research, national and international engagement and profile as well as dedication to the topics addressed to serve on the expert panel (18 experts across Europe). To ensure that the statements were evidence-based, new data identified from a systematic search were reviewed and critically appraised. In the absence of any clear scientific evidence, judgment was based on the professional experience and consensus of the international development group. Prior to publication, the guidelines were reviewed by 206 international practitioners in cancer care delivery and patient representatives.

RESULTS

The updated guidelines cover comprehensively diagnosis and referral, staging, pathology, pre-operative investigations, surgical management (local treatment, groin treatment, sentinel lymph node procedure, reconstructive surgery), (chemo)radiotherapy, systemic treatment, treatment of recurrent disease (vulvar, inguinal, pelvic, and distant recurrences), and follow-up. Management algorithms are also defined.

Ad hoc Analysis of the Phase III ENGOT-OV16/NOVA Study: Niraparib Efficacy in Germline BRCA Wild-type Recurrent Ovarian Cancer with Homologous Recombination Repair Defects

In this analysis, we examined the relationship between progression-free survival (PFS) and mutation status of 18 homologous recombination repair (HRR) genes in patients in the non-germline BRCA-mutated (non-gBRCAm) cohort of the ENGOT-OV16/NOVA trial (NCT01847274), which evaluated niraparib maintenance therapy for patients with recurrent ovarian cancer. This post hoc exploratory biomarker analysis was performed using tumor samples collected from 331 patients enrolled in the phase III ENGOT-OV16/NOVA trial's non-gBRCAm cohort. Niraparib demonstrated PFS benefit in patients with either somatic BRCA-mutated (sBRCAm; HR, 0.27; 95% confidence interval, CI, 0.08–0.88) or BRCA wild-type (BRCAwt; HR, 0.47; 95% CI, 0.34–0.64) tumors. Patients with BRCAwt tumors with other non-BRCA HRR mutations also derived benefit from niraparib (HR, 0.31; 95% CI, 0.13–0.77), as did patients with BRCAwt/HRRwt (HRR wild-type) tumors (HR, 0.49; 95% CI, 0.35–0.70). When patients with BRCAwt/HRRwt tumors were further categorized by genomic instability score (GIS), clinical benefit was observed in patients with homologous recombination–deficient (GIS ≥ 42; HR, 0.33; 95% CI, 0.18–0.61) and in patients with homologous recombination–proficient (HRp; GIS &lt; 42; HR, 0.60; 95% CI, 0.36–0.99) disease. Although patients with sBRCAm, other non-BRCA HRR mutations, or GIS ≥ 42 benefited the most from niraparib treatment, PFS benefit was also seen in HRp (GIS &lt; 42) patients without HRR mutations. These results support the use of niraparib in patients with recurrent ovarian cancer regardless of BRCA/HRR mutation status or myChoice CDx GIS.

Significance:

We retrospectively evaluated the mutational profile of HRR genes in tumor samples from 331 patients from the non-germline BRCA-mutated cohort of the phase III NOVA trial of patients with platinum-sensitive high-grade serous ovarian cancer. Patients with non-BRCA HRR mutations generally benefited from second-line maintenance treatment with niraparib compared with placebo.

Comparison of global treatment guidelines for locally advanced cervical cancer to optimize best care practices: A systematic and scoping review

BACKGROUND

Survival outcomes for cervical cancer differ between countries and world regions. Locally advanced cervical cancer (LACC) is associated with poorer outcomes than early-stage disease. Country-specific variations in diagnostic and treatment recommendations might contribute to differences in LACC outcomes among countries.

OBJECTIVE

We compared international and country-specific guidelines for LACC diagnostic imaging and treatment recommendations.

METHODS

A systematic literature review and targeted search were used to identify cervical cancer treatment guidelines published between January 1999-August 2021. Guidelines were identified via literature databases, health technology assessment databases, disease-specific websites, and health organization websites. The targeted search included guidelines from countries in regions known to have high cervical cancer prevalence or mortality. Non-English guidelines were translated by native speakers or online translation services.

RESULTS

Forty-six guidelines from 31 countries, regions, and international organizations were compared (41/46 using staging criteria, 27 of which used 2009 FIGO). Most guidelines recommended imaging tests for diagnosis and staging. Chest X-ray, intravenous pyelogram, CT, and MRI were commonly recommended for diagnosis and staging while MRI and PET-CT were recommended for the assessment of lymph node status and distant metastases, with a preference for PET-CT over MRI. There was global consensus for cisplatin-based concurrent chemoradiation as primary treatment for stages IIB to IVA, with few exceptions. Treatment recommendations for stages IB2 to IIA2 varied. Most guidelines agreed on adjuvant concurrent chemoradiation after radical hysterectomy when there is a high recurrence risk, and adjuvant radiotherapy when there is an intermediate recurrence risk. Recommendations for other adjuvant and neoadjuvant therapies varied among the guidelines.

CONCLUSIONS

Differences among treatment guidelines by LACC stage might be influenced by staging criteria used, resource availability, and prevention program effectiveness. Addressing these areas may unify guidelines and improve global outcomes. Review and update of guidelines will be important as novel LACC therapies become available.

Clinical research in ovarian cancer: consensus recommendations from the Gynecologic Cancer InterGroup

The Gynecologic Cancer InterGroup (GCIG) sixth Ovarian Cancer Conference on Clinical Research was held virtually in October, 2021, following published consensus guidelines. The goal of the consensus meeting was to achieve harmonisation on the design elements of upcoming trials in ovarian cancer, to select important questions for future study, and to identify unmet needs. All 33 GCIG member groups participated in the development, refinement, and adoption of 20 statements within four topic groups on clinical research in ovarian cancer including first line treatment, recurrent disease, disease subgroups, and future trials. Unanimous consensus was obtained for 14 of 20 statements, with greater than 90% concordance in the remaining six statements. The high acceptance rate following active deliberation among the GCIG groups confirmed that a consensus process could be applied in a virtual setting. Together with detailed categorisation of unmet needs, these consensus statements will promote the harmonisation of international clinical research in ovarian cancer.

Trial in progress update on ENGOT-cx8/GOG-3024/innovaTV 205: Addition of a new cohort with first-line (1L) tisotumab vedotin (TV) + pembrolizumab (pembro) + carboplatin (carbo) ± bevacizumab (bev) in recurrent/metastatic cervical cancer (r/mCC)

TPS5603

Background: Despite the use of platinum-taxane doublets ± bev in eligible patients (pts), overall survival (OS) outcomes for pts with r/mCC remain poor. With the US approval of pembro + chemotherapy ± bev in the 1L setting for r/mCC with ≥1% of programmed death ligand 1–positive cells in the tumor, an unmet need remains for pts who do not meet this threshold and for pts who progress or are intolerant to standard treatment (tx). TV is a tissue factor–directed antibody–drug conjugate that has been granted accelerated approval in the United States for the tx of adults with r/mCC with disease progression on or after chemotherapy. To develop more effective treatments, we investigated TV in combination with agents with known activity in cervical cancer. We conducted a 2-part, multicohort phase 1b/2 trial, ENGOT-cx8/GOG-3024/innovaTV 205 (NCT03786081), to evaluate TV in combination with bev, pembro, or carbo. The phase 1b dose-escalation phase of innovaTV 205 established the recommended phase 2 dose (RP2D) and the feasibility of these doublet combinations (Monk et al, IGCS 2021). Moreover, we recently reported encouraging antitumor activity from the dose-expansion cohort of TV + carbo (1L; confirmed objective response rate [ORR], 55%; median duration of response [DOR], 8.3 mo) and TV + pembro (second-line; confirmed ORR, 38%; median DOR, 13.8 mo) (Vergote et al, ESMO 2021). The current report describes the design of a new, ongoing dose expansion cohort in the innovaTV 205 study to evaluate the combinations of TV, pembro, and carbo ± bev. Methods: A new cohort has been added to the innovaTV 205 study, comprising adult pts with recurrent or stage IVB squamous, adenosquamous, or adenocarcinoma of the cervix with no prior systemic therapy and an Eastern Cooperative Oncology Group score of 0 or 1. Pts will be treated with the RP2D of TV (2.0 mg/kg) + carbo (AUC 5 mg/mL), pembro (200 mg), and bev (15 mg/kg) every 3 weeks or with TV + carbo (AUC 5 mg/mL) and pembro (200 mg). To assess the regimen’s initial tolerability, there will be a dose-limiting toxicity evaluation period that will consist of completion of 1 tx cycle of 21 days for 6 pts enrolled to receive the quadruplet combination. The primary endpoint of this dose expansion phase is confirmed ORR per RECIST v1.1; secondary endpoints include DOR, time to response, progression-free survival, OS, and safety. Enrollment is ongoing in the United States and Europe, with additional sites planned globally. Clinical trial information: NCT03786081.

Randomized phase III study of maintenance selinexor versus placebo in endometrial cancer (ENGOT-EN5/GOG-3055/SIENDO): Impact of subgroup analysis and molecular classification

5511

Background: Endometrial cancers (ECs) are stratified into four molecular categories: wild type TP53 with non-specific molecular profile typically with microsatellite stability (NSMP, p53wt/MSS), DNA polymerase ε exonuclease domain-mutated (POLEmut), microsatellite instability high (MSI) and TP53 abnormal (p53abn). These are associated with specific prognoses. Selinexor (SEL) is a specific XPO1 inhibitor that leads to the nuclear retention and activation of tumor suppressor proteins (TSP) including p53. SEL showed improved progression-free survival (PFS) over placebo (PLB) in the stratification adjusted results of the ENGOT-EN5/GOG-3055/SIENDO study (NCT03555422; ESMO 2022). Methods: The SIENDO study is a prospective, multicenter, double-blind, placebo-controlled, phase 3 study of SEL (80 mg once weekly) vs. PLB (2:1 randomization) as maintenance therapy in 263 patients (pts) with advanced or recurrent EC after one line of taxane-platinum therapy with partial or complete remission. TP53 mutations and MSI were assessed by centralized targeted sequencing and local immunohistochemistry. Classification was based on sequencing 648 genes on tumor samples from 172 pts (107 on SEL), assigned first by POLEmut, then MSI, then p53abn or p53wt (NSMP). Preliminary exploratory analyses based on molecular classification were prespecified in the trial. Results: The SIENDO study resulted in a median progression-free survival (PFS) of 5.7 months (SEL) vs. 3.8 months (PLB), with a stratification adjusted (eCRF) hazard ratio (HR) of 0.70 (p =.024; and a stratification non-adjusted (IRT) HR of 0.76 (p=0.063). Among the 172 patients who underwent molecular classification, those on SEL (107 pts) were classified as follows: 37 (35%) NSMP, 2 (2%) POLEmut, 18 (17%) MSI, and 50 (46%) p53abn. A similar distribution was seen in those on PLB (65 pts): 20 (31%) NSMP; 4 (6%) POLEmut; 8 (12%) MSI; 33 (51%) p53abn. Subgroup analysis of pts with TP53wt showed a PFS of 13.7 mo with SEL vs. 3.7 mo with PLB (HR 0.375; 95% CI, 0.210-0.670; nominal p =.0003) and pts with MSS/pMMR disease had a PFS of 6.9 mo with SEL vs. 5.4 with PLB (HR 0.593; 95% CI, 0.388-0.905, nominal p =.007). An analysis of patients with NSMP (p53wt, MSS) showed a substantial difference in PFS for SEL vs. PLB: medians NR and 3.71 months, respectively (HR 0.163; 95% CI, 0.060-0.444; nominal p <.0001). Analyses of the other 3 molecular categories did not show significant differences in PFS between SEL and PLB. Additional biomarker identification studies assessing tumor genetics and epigenetics are ongoing. Conclusions: SEL showed improved PFS over PLB in the SIENDO study based on the stratification adjusted analysis. As an indirect p53 activator, preliminary exploratory subgroup analyses of SEL showed improvement over PLB amongst the patients with TP53wt, MSS, and the NSMP EC comprising approximately 50% of patients with advanced/recurrent EC. Clinical trial information: NCT03555422.

Time without symptoms or toxicity (TWiST) in patients with newly diagnosed advanced ovarian cancer receiving maintenance olaparib or placebo plus bevacizumab: Analysis of PAOLA-1/ENGOT-ov25 phase III trial

5562

Background: In the Phase III PAOLA-1/ENGOT-ov25 trial (NCT02477644), maintenance olaparib plus bevacizumab (bev) provided a significant progression-free survival (PFS) benefit, compared with placebo plus bev, in patients (pts) with newly diagnosed advanced ovarian cancer in response after platinum-based chemotherapy (Ray-Coquard et al. NEJM 2019). A subgroup analysis revealed a substantial PFS benefit in HRD-positive (including BRCA1/BRCA2 mutation) pts (median PFS 37.2 vs 17.7 months) leading to US and EU labels for this combination. We analyzed TWiST in PAOLA-1, using several definitions of toxicity (TOX) and by molecular subgroups. Methods: Pts were randomized 2:1 to maintenance olaparib (300 mg bid) plus bev (15 mg/kg, Day 1, q3w) or placebo plus bev, stratified by first-line treatment outcome and tumor BRCAm status. TWiST is defined as PFS minus time with TOX after randomization and before disease progression or censoring for progression, and was a prespecified exploratory endpoint. Definitions of significant symptoms or TOX were explored using the following approaches: 1) all grade ≥2 adverse events (AEs); and 2) all grade ≥2 AEs selected to be correlated to olaparib (fatigue, nausea, vomiting, and anemia). Area under PFS curve was split into TOX:TWIST ratio and compared between the two arms. Results: Between May 7, 2015 and August 31, 2017, 806 eligible pts were randomly assigned to olaparib plus bev (n = 537) or placebo plus bev (n = 269), with a median duration of treatment with olaparib of 17.3 months (range 0.03–33.0) for olaparib plus bev arm and 15.6 months (range 0.07–26.2) for placebo plus bev at data cutoff for primary endpoint analysis. In the Intent-to-treat population, median duration of TWiST for all grade ≥2 AEs for olaparib plus bev vs placebo plus bev arms was 14.1 months (95% confidence interval [CI] 12.5–16.1) vs 7.7 months (95% CI 5.9–9.1), respectively; and 21.9 months (95% CI 20.2–22.5) vs 16.6 months (95% CI 14.6–18.0) considering only grade ≥2 AEs linked to olaparib. The difference was particularly significant within the HRD-positive subgroup where median duration of TWiST was 24.4 months (95% CI 19.3–not evaluable [NE]) vs 7.4 months (5.8–11.2) for TOX linked to all grade ≥2 AEs, and 36.6 months (95% CI 31.9–NE) vs 17.4 months (15.1–19.4) linked to olaparib AEs only for the olaparib plus bev and placebo plus bev arms, respectively. Conclusions: The substantial PFS benefit provided by maintenance olaparib plus bev vs placebo plus bev in pts with newly diagnosed advanced ovarian cancer was supported by significant TWiST benefit. TWiST analyses, including all grade ≥2 symptoms or toxicity related to treatment, confirmed the clinically meaningful benefit from the combination, notably in the HRD-positive subgroup. Clinical trial information: NCT02477644.

Dostarlimab in advanced/recurrent (AR) mismatch repair deficient/microsatellite instability–high or proficient/stable (dMMR/MSI-H or MMRp/MSS) endometrial cancer (EC): The GARNET study

5509

Background: Dostarlimab is a programmed death 1 (PD-1) inhibitor approved in the U.S. as a monotherapy in patients (pts) with dMMR AR EC that has progressed on or after treatment with a platinum-containing regimen or dMMR solid tumors that have progressed on or after prior treatment, with no satisfactory alternative treatment options; and in the E.U. as a monotherapy in pts with dMMR/MSI-H AR EC that has progressed on or after treatment with a platinum-containing regimen. Here, we report on efficacy and safety in the 2 expansion cohorts of the GARNET trial that enrolled pts with EC. Methods: GARNET is a multicenter, open-label, single-arm phase 1 study. Pts were assigned to cohort A1 (dMMR/MSI-H EC) or cohort A2 (MMRp/MSS EC) based on local assessment. Pts received 500 mg of dostarlimab IV Q3W for 4 cycles, then 1,000 mg Q6W until disease progression, discontinuation, or withdrawal. The primary endpoints are ORR and DOR by blinded independent central review using RECIST v1.1. Results: For this third interim analysis, 153 dMMR/MSI-H and 161 MMRp/MSS pts were enrolled and dosed. Of these, 143 dMMR/MSI-H and 156 MMRp/MSS pts had measurable disease at baseline and ≥ 6 mo of follow-up and were included in the efficacy-evaluable population. ORRs were 45.5% (dMMR/MSI-H) and 15.4% (MMRp/MSS; Table). Median (m) DORs were not reached (NR; dMMR/MSI-H) and 19.4 mo (MMRp/MSS). Probability of PFS at 6, 9, and 12 mo was 49.5%, 48.0%, and 46.4% in dMMR/MSI-H EC and 35.8%, 31.3%, and 29.4% in MMRp/MSS EC, respectively. mOS was NR (dMMR/MSI-H) and 16.9 mo (MMRp/MSS). Overall, 27 pts (8.6%) discontinued treatment because of a treatment-related adverse event (TRAE; 13 dMMR/MSI-H, 14 MMRp/MSS). The majority of TRAEs were grade 1 or 2. The most common any-grade TRAEs were fatigue (56; 17.8%), diarrhea (46; 14.6%), and nausea (43; 13.7%). No deaths were attributed to dostarlimab in the EC cohorts. Hypothyroidism (12; 8%) was the most common any-grade immune-related TRAE. Conclusions: Dostarlimab demonstrated durable antitumor activity in both dMMR/MSI-H and MMRp/MSS AR EC. dMMR/MSI-H was associated with better outcomes: a higher response rate and longer PFS and OS. Safety was consistent with other PD-1 antibodies. Clinical trial information: NCT02715284. [Table: see text]

KEYNOTE-C93/GOG-3064/ENGOT-en15: A phase 3, randomized, open-label study of first-line pembrolizumab versus platinum-doublet chemotherapy in mismatch repair deficient advanced or recurrent endometrial carcinoma

TPS5623

Background: Carboplatin-paclitaxel chemotherapy (with trastuzumab for HER2+ uterine serous carcinoma) is the standard of care first-line systemic treatment for recurrent or metastatic endometrial carcinoma (EC), which has a 5-year relative survival rate of only 17%. Worse survival outcomes have been shown for the mismatch repair deficient (dMMR) subtype of EC. Pembrolizumab (pembro), an anti-PD-1 antibody, showed compelling antitumor activity in previously treated, advanced MSI-H/dMMR EC in the phase 2 KEYNOTE-158 study (ORR, 48%; median duration of response [DOR], not reached; O’Malley JCO 2022). KEYNOTE-C93/GOG-3064/ENGOT-en15 (NCT05173987) is a phase 3, randomized, open-label study evaluating first-line pembro versus carboplatin-paclitaxel chemotherapy in patients with dMMR advanced or recurrent EC. Methods: Patients aged ≥18 years with histologically confirmed stage III/IV recurrent EC including carcinosarcoma (mixed Mullerian tumor), radiographically evaluable disease (measurable or nonmeasurable per RECIST v1.1), no prior systemic therapy (prior radiation with or without radiosensitizing chemotherapy > 2 weeks before first dose or prior hormonal therapy ≥1 week before randomization is permitted), and an ECOG PS ≤1 are eligible. Patients must have central confirmation of dMMR status. Approximately 350 patients will be randomized 1:1 to receive pembro 400 mg IV Q6W for 18 cycles (̃2 years) or carboplatin AUC 5 or 6 mg/mL/min IV Q3W and paclitaxel 175 mg/m2 IV Q3W for 6 cycles (with option for > 6 cycles). Trastuzumab is permitted for patients in the chemotherapy arm with HER2+ serous EC. Randomization is stratified by disease status (newly diagnosed advanced EC vs recurrent EC) and histology (endometrioid vs nonendometrioid). Treatment will continue for the specified number of cycles or until PD or unacceptable toxicity. Patients in the chemotherapy arm have the option to receive pembro following confirmed PD by blinded independent central review (BICR). Tumor imaging will be performed Q9W from randomization to week 54 and Q12W thereafter. AEs will be assessed from randomization to 30 days (90 days for serious AEs) after treatment discontinuation and graded per NCI CTCAE version 5.0. Dual primary endpoints are PFS per RECIST v1.1 by BICR and OS. Secondary endpoints are ORR, disease control rate, and DOR per RECIST v1.1 by BICR; PFS per RECIST v1.1 by investigator review; PFS2 (ie, time from randomization to PD per investigator assessment or death from any cause after start of subsequent anticancer therapy); safety; and patient-reported outcomes. PFS and OS will be estimated by the Kaplan-Meier method, with treatment differences assessed by the stratified log-rank test and HRs with 95% CIs determined using a Cox proportional hazard model. Enrollment is ongoing. Clinical trial information: NCT05173987.

European experts consensus: BRCA/homologous recombination deficiency testing in first-line ovarian cancer

BACKGROUND

Homologous recombination repair (HRR) enables fault-free repair of double-stranded DNA breaks. HRR deficiency is predicted to occur in around half of high-grade serous ovarian carcinomas. Ovarian cancers harbouring HRR deficiency typically exhibit sensitivity to poly-ADP ribose polymerase inhibitors (PARPi). Current guidelines recommend a range of approaches for genetic testing to identify predictors of sensitivity to PARPi in ovarian cancer and to identify genetic predisposition.

DESIGN

To establish a European-wide consensus for genetic testing (including the genetic care pathway), decision making and clinical management of patients with recently diagnosed advanced ovarian cancer, and the validity of biomarkers to predict the effectiveness of PARPi in the first-line setting. The collaborative European experts' consensus group consisted of a steering committee (n = 14) and contributors (n = 84). A (modified) Delphi process was used to establish consensus statements based on a systematic literature search, conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines.

RESULTS

A consensus was reached on 34 statements amongst 98 caregivers (including oncologists, pathologists, clinical geneticists, genetic researchers, and patient advocates). The statements concentrated on (i) the value of testing for BRCA1/2 mutations and HRR deficiency testing, including when and whom to test; (ii) the importance of developing new and better HRR deficiency tests; (iii) the importance of germline non-BRCA HRR and mismatch repair gene mutations for predicting familial risk, but not for predicting sensitivity to PARPi, in the first-line setting; (iv) who should be able to inform patients about genetic testing, and what training and education should these caregivers receive.

CONCLUSION

These consensus recommendations, from a multidisciplinary panel of experts from across Europe, provide clear guidance on the use of BRCA and HRR deficiency testing for recently diagnosed patients with advanced ovarian cancer.

Patient perspectives and experiences of the rapid implementation of digital consultations during COVID-19 - a qualitative study among women with gynecological cancer

Purpose

Due to the first COVID-19 outbreak and subsequent restrictions, standard practice for gynecological cancer quickly evolved to include additional digital consultations. Women with gynecological cancer have a high need for information and experience a high symptom burden. We aimed to explore the experiences and perspectives of the rapid implementation of digital consultations during COVID-19.

Methods

We conducted individual telephone interviews with patients with gynecological cancer 1–4 days after a telephone or video consultation during the COVID-19 outbreak in April and May 2020. We applied Braun and Clarke’s thematic analysis to analyze the qualitative data.

Results

Thirty-two patients with ovarian (50%), cervical (35%), vulvar (12%), and vaginal cancer (3%) participated in the study. The patients experienced that, combined, cancer and COVID-19 restrictions made their situation twice as challenging. In general, the patients valued face-to-face consultations, recommending that they were ideal for the initial appointment to build trust. Overall, there was a willingness to participate in digital consultations because of the restrictions, but the results also showed varying degrees of openness and that individual solutions were favored.

Conclusion

The findings of this study show that digital consultations were an accepted alternative during COVID-19. Even though this temporary solution was deemed to be beneficial for practical reasons, patients also experienced digital consultations to be impersonal. A key message is that face–to–face encounters create the foundation to establish a trusting relationship from where a valuable dialogue arises. Digital consultations should therefore be implemented with caution since no one-size-fits-all model is recommended. Among patients with gynecological cancer, however, digital technologies represent a promising and flexible method depending on the purpose of consultations, patient preferences, and needs.

Cancer of the corpus uteri: 2021 update

Endometrial cancer is the most common gynecological malignancy in high‐ and middle‐income countries. Although the overall prognosis is relatively good, high‐grade endometrial cancers have a tendency to recur. Recurrence needs to be prevented since the prognosis for recurrent endometrial cancer is dismal. Treatment tailored to tumor biology is the optimal strategy to balance treatment efficacy against toxicity. Since The Cancer Genome Atlas defined four molecular subgroups of endometrial cancers, the molecular factors are increasingly used to define prognosis and treatment. Standard treatment consists of hysterectomy and bilateral salpingo‐oophorectomy. Lymphadenectomy (and increasingly sentinel node biopsy) enables identification of lymph node‐positive patients who need adjuvant treatment, including radiotherapy and chemotherapy. Adjuvant therapy is used for Stage I–II patients with high‐risk factors and Stage III patients; chemotherapy is especially used in non‐endometrioid cancers and those in the copy‐number high molecular group characterized by TP53 mutation. In advanced disease, a combination of surgery to no residual disease and chemotherapy with or without radiotherapy results in the best outcome. Surgery for recurrent disease is only advocated in patients with a good performance status with a relatively long disease‐free interval.

The latest state‐of‐the‐art treatment for endometrial cancer is described, incorporating the most recent new data that influence its clinical management.

SIENDO/ENGOT-EN5/GOG-3055: A randomized phase 3 trial of maintenance selinexor versus placebo after combination platinum-based chemotherapy in advanced or recurrent endometrial cancer

TPS5610

Background: Endometrial cancer (EC) is the most common gynecologic malignancy. Options for advanced or recurrent EC following platinum-based therapy and/or radiotherapy are limited and prognosis remains poor. Selinexor is a novel, oral selective inhibitor of nuclear export (SINE) which forces nuclear retention and activation of tumor suppressor proteins. Selinexor in combination with low dose dexamethasone is approved for relapsed/refractory multiple myeloma. In addition, selinexor monotherapy has demonstrated broad activity in other hematologic malignancies and solid tumors. In a phase 2 study, 50 mg/m2 (̃80 mg) selinexor administered twice weekly demonstrated a disease control rate ( SD ≥ 12 weeks or a PR) of 35% with 2 confirmed partial responses among 23 heavily pretreated EC patients); similar results were observed in 60 pts with platinum resistant or refractory ovarian cancer (median 5 prior regimens, ORR 8%, DCR 30%) (Vergote I et al. Gynecol Oncol 2020). In the absence of approved maintenance therapies, we conducted this study to evaluate the efficacy of selinexor compared with placebo as maintenance therapy in patients with advanced or recurrent EC following platinum-based chemotherapy. Methods: This is a multicenter, double-blind, placebo-controlled, randomized phase 3 study in patients in partial (PR) or complete remission (CR) after completing at least 12 weeks of taxane-platinum combination therapy for primary Stage IV disease and recurrent disease (i.e., relapse after primary therapy for early stage disease including surgery and/or adjuvant therapy). A total of 248 patients will be enrolled at 80 sites in Europe, North America, and Israel. Patients will be randomized in a 2:1 ratio to either maintenance therapy with 80 mg oral selinexor once weekly or placebo. Stratification factors include primary Stage IV versus first recurrence at the time of taxane-platinum therapy and disease status after chemotherapy (PR vs CR). Treatment will continue until disease progression. The primary endpoint is progression free survival (PFS) per RECIST v1.1. Secondary endpoints include disease-specific survival, overall survival, time to first subsequent therapy, time to second subsequent therapy, PFS on subsequent therapy and safety and tolerability. The study is currently open and enrolling patients. Clinical trial information: NCT03555422.

ENGOT-en11/GOG-3053/KEYNOTE-B21: Phase 3 study of pembrolizumab or placebo in combination with adjuvant chemotherapy with/without radiotherapy in patients with newly diagnosed high-risk endometrial cancer

TPS5608

Background: Pembrolizumab, a selective humanized anti–PD-1 monoclonal antibody, has demonstrated activity in patients with previously treated mismatch repair (MMR) deficient (dMMR; 57.1% ORR as monotherapy and 63.6% ORR as combination therapy with lenvatinib) and MMR proficient (pMMR; 36.2% ORR as combination therapy with lenvatinib) endometrial cancer (EC). ENGOT-en11/GOG-3053/KEYNOTE-B21 is a phase 3, randomized, double-blind study of pembrolizumab or placebo in combination with adjuvant chemotherapy with/without radiotherapy in patients with EC. Methods: Eligible patients are ≥18 years old with newly diagnosed, histologically confirmed high-risk (stage I/II non-endometrioid, stage III/IVa, p53 abnormality) EC (carcinoma or carcinosarcoma) following surgery with curative intent with no evidence of disease post-operatively or on imaging, and without prior systemic therapy/radiotherapy. In total, ̃990 patients are randomized to receive pembrolizumab 200 mg or placebo Q3W for 6 cycles + chemotherapy (carboplatin area under the curve [AUC] 5 or 6 + paclitaxel 175 mg/m2 Q3W or carboplatin AUC 2 or 2.7 + paclitaxel 60 mg/m2 QW) in stage 1. Patients receive pembrolizumab 400 mg or placebo Q6W for 6 cycles in stage 2 per their treatment assignment. At the investigator’s discretion, radiotherapy (external beam radiotherapy [EBRT] and/or brachytherapy) ± radiosensitizing cisplatin 50 mg/m2 (days 1 and 29) may be administered after completion of chemotherapy. Randomization is stratified by MMR status (pMMR vs dMMR) and, within pMMR, by planned radiation therapy (cisplatin-EBRT vs EBRT vs no EBRT), histology (endometrioid vs non-endometrioid), and International Federation of Gynecology and Obstetrics (FIGO) surgical stage (I/II vs III/IVA). Dual primary endpoints are disease-free survival (DFS; per investigator assessment) and overall survival (OS), both estimated by the Kaplan-Meier method, with a stratified log-rank test to assess treatment differences and a Cox proportional hazard model with Efron’s method of tie handling to assess the magnitude of treatment differences. Secondary endpoints include DFS (per blinded independent central review), DFS (per investigator assessment) and OS by biomarker status (PD-L1 and tumor mutational burden), safety (per National Cancer Institute Common Terminology Criteria for Adverse Events version 5.0) and quality of life (per European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 [EORTC QLQ-C30] and Endometrial Cancer Module [EORTC QLQ-EN24]). The study began enrollment in December 2020. Clinical trial information: NCT04634877.

Molecular results and potential biomarkers identified from MILO/ENGOT-ov11 phase 3 study of binimetinib versus physicians choice of chemotherapy (PCC) in recurrent low-grade serous ovarian cancer (LGSOC)

5519

Background: Lower responses to chemotherapy and the unique molecular profile of LGSO led to the adoption of MEK-inhibitors for this disease. Updated analysis from the MILO/ENGOT-ov11 phase III study of binimetinib vs PCC in recurrent LGSOC showed response rate of 24% in those treated with binimetinib (JCO, 2020; NCT01849874). Here we present results of the post-hoc tumor tissue biomarker analysis performed with MILO/ENGOT-ov11. Methods: Mutational/copy number analysis was performed via Foundation Medicine on archival tissue obtained prior to randomization. Unbiased univariate analysis was used to test association between mutation status and outcomes in binimetinib and PCC treated patients. Outcomes examined were progression free survival (PFS), binary response by local RECIST 1.1 (complete or partial response [CR/PR] vs. stable [SD] or progressive disease [PD]), and ordinal response. Kaplan-Meier was used to estimate PFS. Cox regression, binary logistic regression, and ordinal logistic regression were used to examine relationship between mutation status and outcomes. Results: MILO/ENGOT-OV11 enrolled 341 patients from June, 2013 to April, 2016. Patients were randomized 2:1 to binimetinib or PCC. Based on January 1, 2020 data cut-off the data is as-is, amongst those patients treated with binimetinib with molecular results available, PFS data is available for 144 and response rate (RR) data for 135. There were 47 mutations detected in ≥5% of patients, most commonly KRAS (33%). Patients harboring a KRAS mutation had 3.4 times the odds of responding to treatment with binimetinib as patients without KRAS mutation (95% CI 1.57,7.67; p-value 0.002). There was no difference in effect of KRAS G12V mutation vs other KRAS mutation on PFS (PFS HR 1.06; 95% CI:0.53, 2.12; p value 0.9). In the 135 patients with binimetinib RR data, other MAPK mutations were identified as follows; NRAS in 11(8.1%), BRAFV600E in 8(5.9%), RAF1 in 2 (1.5%), NF1 in 7 (5.2%). In patients with MAPK mutation (as defined above) the RR was 41% vs 13% in those without MAPK mutation. PFS was significantly better in patients treated with binimetinib harboring MAPK mutation vs those without (HR 0.5; 95% CI 0.31, 0.79; p = 0.003). In patients treated with PCC there was a nonsignificant trend towards improved PFS in those with MAPK mutation vs those without (HR 0.82; 95% CI 0.43,1.59; p = 0.6). A test for interaction between treatment and MAPK pathway was not significant by Cox regression model (p = 0.32). Conclusions: While this hypothesis generating analysis is limited by multiple testing, higher response rates and longer PFS were seen in those patients with LGSOC treated with binimetinib who harbored MAPK mutations, most commonly in KRAS. Somatic tumor testing should be routinely performed in patients with recurrent LGSOC to aid in clinical decision making. Clinical trial information: NCT01849874.

Niraparib efficacy and safety in patients with BRCA mutated (BRCAm) ovarian cancer: Results from three phase 3 niraparib trials

5518

Background: Niraparib has been approved for the maintenance treatment of patients with advanced ovarian, fallopian tube, or primary peritoneal cancer after front-line chemotherapy (CT) and in the recurrent setting. Here, we summarize niraparib efficacy and safety in patients with BRCAm OC across three phase 3 trials: PRIMA/ENGOT-OV26/GOG-3012 (PRIMA; NCT02655016), ENGOT-OV16/NOVA (NOVA; NCT01847274), and NORA (NCT03705156). Methods: Patients enrolled in the PRIMA trial had newly diagnosed advanced ovarian, fallopian tube, or primary peritoneal cancer. All patients had stage III or IV high-grade serous or endometrioid tumors and had a complete or partial response to their first-line platinum-based CT treatment. Subgroup analysis by tumor BRCAm status was prespecified. Patients enrolled in the NOVA and NORA studies had platinum-sensitive, high-grade serous ovarian, fallopian tube, or primary peritoneal cancer. Patients had already received at least 2 lines of platinum-based CT regimens. In both studies, subgroup analysis by germline BRCAm status was prespecified. The primary endpoint in all trials was progression-free survival (PFS) by blinded independent central review. Results: The BRCAm populations from each trial are as follows: 223 (148 BRCA1m and 75 BRCA2m) from the PRIMA trial, 203 (128 BRCA1m, 69 BRCA2m, and 13 BRCA1/2m) from the NOVA trial, and 100 (78 BRCA1m, 21 BRCA2m, and 1 BRCA1/2m) from the NORA trial. PFS results are shown in the Table. Across the 3 trials, the most common treatment-emergent adverse events were thrombocytopenia, anemia, neutropenia, and hypertension. Conclusions: Patients with BRCAm OC derived a significant PFS benefit from niraparib maintenance treatment across all 3 trials. No new safety signals were identified. Clinical trial information: NCT02655016, NCT01847274, NCT03705156. [Table: see text]

Uplift (ENGOT-ov67): A pivotal cohort to evaluate XMT-1536 (upifitamab rilsodotin), a NaPi2b-directed antibody drug conjugate for platinum-resistant ovarian cancer

TPS5607

Background: XMT-1536 (upifitamab rilsodotin), is a first-in-class Dolaflexin ADC targeting NaPi2b, a sodium-dependent phosphate transport protein, broadly expressed in solid tumors such as serous epithelial ovarian cancer (OC) and non-small cell lung adenocarcinoma. XMT-1536 uses the Dolaflexin platform to deliver approximately 10 DolaLock auristatin payload molecules per antibody and is being evaluated in a Phase I study (NCT03319628). Observation of preliminary antitumor activity was reported in the ovarian cancer expansion cohort, including in patients previously treated with bevacizumab and PARPi (Tolcher et al, ASCO 2019; Richardson et al, ASCO 2019; Hamilton et al, ESMO 2020). Updated data on the OC cohort included 31 patients with higher NaPi2b expression as of December 2020 (Mersana Therapeutics, 2021). In these patients, the ORR was 32% and the DCR was 74%. Complete responses were observed in 2 patients with platinum-resistant ovarian cancer, both of whom had received prior treatment with bevacizumab and PARP inhibitors. Platinum resistant ovarian cancer remains a serious unmet medical need as treatment options are limited and response rates to these treatments are low. Based on the favorable safety and efficacy profile of XMT-1536, UPLIFT was designed as a Phase 2 single-arm registrational cohort of patients with platinum resistant ovarian cancer as part of the ongoing Phase I FIH dose escalation and expansion study to accelerate development and provide a streamlined pathway to regulatory review. Methods: The UPLIFT cohort is enrolling patients with platinum resistant high grade serous ovarian, fallopian tube and primary peritoneal cancer with up to 4 prior lines of therapy. The RP2D of XMT-1536 was determined to be 43 mg/m2 administered intravenously every 4 weeks (q4w) and will be the dose evaluated in the UPLIFT cohort. UPLIFT will enroll approximately 180 patients with platinum-resistant advanced ovarian cancer to obtain approximately 100 patients with higher NaPi2b expression. Prior bevacizumab is required for those patients with 1 or 2 prior lines of therapy. Tumor samples (fresh or archived) will be collected prior to enrollment for retrospective tumor tissue evaluation of NaPi2b expression. The primary objective is assessment of confirmed objective response rate to XMT-1536 as assessed by Investigator in patients with higher NaPi2b expression. Secondary endpoints include confirmed objective response rate regardless of NaPi2b expression, duration of response, and adverse events. Correlative aims include assessing blood and tissue biomarkers for association with clinical benefit. This study is being conducted in collaboration with ENGOT and GOG. Patients will be enrolled globally. Clinical trial information: NCT03319628.

ESGO/ESTRO/ESP guidelines for the management of patients with endometrial carcinoma

A European consensus conference on endometrial carcinoma was held in 2014 to produce multidisciplinary evidence-based guidelines on selected questions. Given the large body of literature on the management of endometrial carcinoma published since 2014, the European Society of Gynaecological Oncology (ESGO), the European SocieTy for Radiotherapy & Oncology (ESTRO) and the European Society of Pathology (ESP) jointly decided to update these evidence-based guidelines and to cover new topics in order to improve the quality of care for women with endometrial carcinoma across Europe and worldwide. ESGO/ESTRO/ESP nominated an international multidisciplinary development group consisting of practicing clinicians and researchers who have demonstrated leadership and expertise in the care and research of endometrial carcinoma (27 experts across Europe). To ensure that the guidelines are evidence-based, the literature published since 2014, identified from a systematic search was reviewed and critically appraised. In the absence of any clear scientific evidence, judgment was based on the professional experience and consensus of the development group. The guidelines are thus based on the best available evidence and expert agreement. Prior to publication, the guidelines were reviewed by 191 independent international practitioners in cancer care delivery and patient representatives. The guidelines comprehensively cover endometrial carcinoma staging, definition of prognostic risk groups integrating molecular markers, pre- and intra-operative work-up, fertility preservation, management for early, advanced, metastatic, and recurrent disease and palliative treatment. Principles of radiotherapy and pathological evaluation are also defined.

ESGO/ESTRO/ESP Guidelines for the management of patients with endometrial carcinoma

A European consensus conference on endometrial carcinoma was held in 2014 to produce multidisciplinary evidence-based guidelines on selected questions. Given the large body of literature on the management of endometrial carcinoma published since 2014, the European Society of Gynaecological Oncology (ESGO), the European SocieTy for Radiotherapy & Oncology (ESTRO) and the European Society of Pathology (ESP) jointly decided to update these evidence-based guidelines and to cover new topics in order to improve the quality of care for women with endometrial carcinoma across Europe and worldwide. ESGO/ESTRO/ESP nominated an international multidisciplinary development group consisting of practicing clinicians and researchers who have demonstrated leadership and expertise in the care and research of endometrial carcinoma (27 experts across Europe). To ensure that the guidelines are evidence-based, the literature published since 2014, identified from a systematic search was reviewed and critically appraised. In the absence of any clear scientific evidence, judgment was based on the professional experience and consensus of the development group. The guidelines are thus based on the best available evidence and expert agreement. Prior to publication, the guidelines were reviewed by 191 independent international practitioners in cancer care delivery and patient representatives. The guidelines comprehensively cover endometrial carcinoma staging, definition of prognostic risk groups integrating molecular markers, pre- and intra-operative work-up, fertility preservation, management for early, advanced, metastatic, and recurrent disease and palliative treatment. Principles of radiotherapy and pathological evaluation are also defined.

ESGO/ESTRO/ESP guidelines for the management of patients with endometrial carcinoma

A European consensus conference on endometrial carcinoma was held in 2014 to produce multi-disciplinary evidence-based guidelines on selected questions. Given the large body of literature on the management of endometrial carcinoma published since 2014, the European Society of Gynaecological Oncology (ESGO), the European SocieTy for Radiotherapy and Oncology (ESTRO), and the European Society of Pathology (ESP) jointly decided to update these evidence-based guidelines and to cover new topics in order to improve the quality of care for women with endometrial carcinoma across Europe and worldwide.

Perspectives, fears and expectations of patients with gynaecological cancers during the COVID-19 pandemic: A Pan-European study of the European Network of Gynaecological Cancer Advocacy Groups (ENGAGe)

Background

The impact of the COVID‐19 pandemic on European gynaecological cancer patients under active treatment or follow‐up has not been documented. We sought to capture the patient perceptions of the COVID‐19 implications and the worldwide imposed treatment modifications.

Methods

A patient survey was conducted in 16 European countries, using a new COVID‐19‐related questionnaire, developed by ENGAGe and the Hospital Anxiety & Depression Scale questionnaire (HADS). The survey was promoted by national patient advocacy groups and charitable organisations.

Findings

We collected 1388 forms; 592 online and 796 hard‐copy (May, 2020). We excluded 137 due to missing data. Median patients’ age was 55 years (range: 18–89), 54.7% had ovarian cancer and 15.5% were preoperative. Even though 73.2% of patients named cancer as a risk factor for COVID‐19, only 17.5% were more afraid of COVID‐19 than their cancer condition, with advanced age (>70 years) as the only significant risk factor for that. Overall, 71% were concerned about cancer progression if their treatment/follow‐up was cancelled/postponed. Most patients (64%) had their care continued as planned, but 72.3% (n = 892) said that they received no information around overall COVID‐19 infection rates of patients and staff, testing or measures taken in their treating hospital. Mean HADS Anxiety and Depression Scores were 8.8 (range: 5.3–12) and 8.1 (range: 3.8–13.4), respectively. Multivariate analysis identified high HADS‐depression scores, having experienced modifications of care due to the pandemic and concern about not being able to visit their doctor as independent predictors of patients’ anxiety.

Interpretation

Gynaecological cancer patients expressed significant anxiety about progression of their disease due to modifications of care related to the COVID‐19 pandemic and wished to pursue their treatment as planned despite the associated risks. Healthcare professionals should take this into consideration when making decisions that impact patients care in times of crisis and to develop initiatives to improve patients’ communication and education.

Therapeutic options following second-line platinum-based chemotherapy in patients with recurrent ovarian cancer: Comparison of active surveillance and maintenance treatment

Most women with advanced ovarian cancer respond to initial treatment, consisting of surgical resection and ≈6 cycles of platinum-based chemotherapy. However, disease recurrence occurs in most patients, and subsequent therapies become necessary. Historically, close monitoring following treatment (active surveillance) was the only available option, as continued maintenance chemotherapy treatment led to increased toxicity without providing any meaningful clinical benefit. Recently, targeted therapy with the angiogenesis inhibitor bevacizumab and the poly(ADP-ribose) polymerase (PARP) inhibitors olaparib, niraparib, and rucaparib have demonstrated significant clinical benefits as maintenance treatment for recurrent disease. Despite consensus guidelines recommending their use, maintenance treatments are currently underutilized. Here, we review evidence from pivotal clinical trials of approved second-line maintenance treatments demonstrating efficacy in terms of progression-free survival and postprogression efficacy outcomes for patients with recurrent ovarian cancer. Adverse events frequently associated with bevacizumab include hypertension, proteinuria, and non-central nervous system bleeding, whereas PARP inhibitors are associated with nausea, vomiting, fatigue, and anemia. Patient-centered outcomes analyses show that PARP inhibitors provide significant benefits to patient health status, even when accounting for the toxicities associated with treatment. Many factors influence the selection of second-line maintenance treatment for patients with recurrent ovarian cancer, including the maintenance treatment received in the first-line setting. Overall, targeted maintenance treatment represents a new standard of care for patients with ovarian cancer, and we recommend that maintenance treatment should be offered to all eligible patients with recurrent ovarian cancer.

MILO/ENGOT-ov11: Binimetinib Versus Physician's Choice Chemotherapy in Recurrent or Persistent Low-Grade Serous Carcinomas of the Ovary, Fallopian Tube, or Primary Peritoneum

PURPOSE

Low-grade serous ovarian carcinomas (LGSOCs) have historically low chemotherapy responses. Alterations affecting the MAPK pathway, most commonly KRAS/BRAF, are present in 30%-60% of LGSOCs. The purpose of this study was to evaluate binimetinib, a potent MEK1/2 inhibitor with demonstrated activity across multiple cancers, in LGSOC.

METHODS

This was a 2:1 randomized study of binimetinib (45 mg twice daily) versus physician's choice chemotherapy (PCC). Eligible patients had recurrent measurable LGSOC after ≥ 1 prior platinum-based chemotherapy but ≤ 3 prior chemotherapy lines. The primary end point was progression-free survival (PFS) by blinded independent central review (BICR); additional assessments included overall survival (OS), overall response rate (ORR), duration of response (DOR), clinical-benefit rate, biomarkers, and safety.

RESULTS

A total of 303 patients were randomly assigned to an arm of the study at the time of interim analysis (January 20, 2016). Median PFS by BICR was 9.1 months (95% CI, 7.3 to 11.3) for binimetinib and 10.6 months (95% CI, 9.2 to 14.5) for PCC (hazard ratio,1.21; 95%CI, 0.79 to 1.86), resulting in early study closure according to a prespecified futility boundary after 341 patients had enrolled. Secondary efficacy end points were similar in the two groups: ORR 16% (complete response [CR]/partial responses[PRs], 32) versus 13% (CR/PRs, 13); median DOR, 8.1 months (range, 0.03 to ≥ 12.0 months) versus 6.7 months (0.03 to ≥ 9.7 months); and median OS, 25.3 versus 20.8 months for binimetinib and PCC, respectively. Safety results were consistent with the known safety profile of binimetinib; the most common grade ≥ 3 event was increased blood creatine kinase level (26%). Post hoc analysis suggests a possible association between KRAS mutation and response to binimetinib. Results from an updated analysis (n = 341; January 2019) were consistent.

CONCLUSION

Although the MEK Inhibitor in Low-Grade Serous Ovarian Cancer Study did not meet its primary end point, binimetinib showed activity in LGSOC across the efficacy end points evaluated. A higher response to chemotherapy than expected was observed and KRAS mutation might predict response to binimetinib.

Results of the interprofessional and interdisciplinary Berlin round table on patient-reported outcomes, quality of life, and treatment expectations of patients with gynecological cancer under maintenance treatment

BACKGROUND

Patients' reported outcomes and their perspectives around their therapeutic management is a field of continuously increasing relevance in gynecological oncology. We report the results of the Berlin dialog on seven patient-reported parameters and outcomes concerning chemotherapy and maintenance treatment in patients with gynecological cancer.

METHODS

Key opinion leaders in gynecological oncology from different European counties and representatives of leading patients' advocate groups in Berlin held a consensus meeting in Berlin on April 6, 2019. Seven topics of interest were identified in advance around quality of life, iatrogenic toxicity, treatment decision-making processes, sexuality, participation in clinical trials, second opinion, and long-term survivors with the the following standard operating procedure for processing and discussion: (1) agreement on its relevance; (2) literature review, and (3) discussion and consensus statements.

RESULTS

All main topics reached a consensus approval. The defined statements emphasized the importance of patients' role in incorporating and establishing quality of life as an outcome parameter in clinical trials. Furthermore, discussants raised the importance of identifying new tools for reflecting patient-reported iatrogenic toxicity as well as emphasizing patients' rights in providing personal information, access to second opinion in the decision-making process, and their participation in clinical trials.

CONCLUSION

The results of this round table meeting could help redefine perspectives on the discussed topics and the importance for therapeutic management as well as for trial designs.

The forefront of ovarian cancer therapy: update on PARP inhibitors

BACKGROUND

In recurrent ovarian cancer, poly(ADP-ribose) polymerase (PARP)-inhibiting agents have transformed the treatment of platinum-sensitive disease. New data support use of PARP inhibitors earlier in the treatment algorithm.

DESIGN

We review results from recent phase III trials evaluating PARP inhibitors as treatment and/or maintenance therapy for patients with newly diagnosed ovarian cancer. We discuss the efficacy and safety of these agents in the all-comer and biomarker-selected populations studied in clinical trials, and compare the strengths and limitations of the various trial designs. We also consider priorities for future research, with a particular focus on patient selection and future regimens for populations with high unmet need.

RESULTS

Four phase III trials (SOLO-1, PAOLA-1/ENGOT-OV25, PRIMA/ENGOT-OV26 and VELIA/GOG-3005) demonstrated remarkable improvements in progression-free survival with PARP inhibitor therapy (olaparib, niraparib or veliparib) for newly diagnosed ovarian cancer. Differences in trial design (treatment and/or maintenance setting; single agent or combination; bevacizumab or no bevacizumab), patient selection (surgical outcome, biomarker eligibility, prognosis) and primary analysis population (intention-to-treat, BRCA mutated or homologous recombination deficiency positive) affect the conclusions that can be drawn from these trials. Overall survival data are pending and there is limited experience regarding long-term safety.

CONCLUSIONS

PARP inhibitors play a pivotal role in the management of newly diagnosed ovarian cancer, which will affect subsequent treatment choices. Refinement of testing for patient selection and identification of regimens to treat populations that appear to benefit less from PARP inhibitors are a priority.

Incorporating Parp-inhibitors in Primary and Recurrent Ovarian Cancer: A Meta-analysis of 12 phase II/III randomized controlled trials

BACKGROUND

The second decade of 2000s is witnessing a new ovarian cancer (OC) paradigm shift thanks to the results recently obtained by a new class of targeted agents: the Poly(ADP-ribose)polymerase (PARP)-Inhibitors (PARPi). Aim of this meta-analysis is to analyze available results obtained with PARPi, administered alone or in combination with chemo- and/or target-therapies in terms of efficacy and safety for the treatment of recurrent and primary advanced OC.

METHODS

On December 2019, all published phase II/III randomized clinical studies were systematically searched using the terms "[Parp-Inhibitor] AND [ovar*]". Twelve phase II/III randomized controlled trials were identified, with a total number of 5171 patients included.

RESULTS

Results demonstrated that PARPi account for a significant improvement of PFS in both recurrent and primary OC setting, independently from their administration schedule and independently from patients' BRCA mutational status. Moreover, patients harboring a Homologous Recombination Deficiency (HRD) positive testing primary or recurrent OC progress significantly later after PARPi administration/association. Results also reported that PARPi increase the occurrence of severe (G3-G4) anemia. Furthermore, severe fatigue occurred more frequently among patients subjected to PARPi combined with chemotherapy and to PARPi plus Bevacizumab. Finally, a significant increase in severe high blood pressure occurrence was observed when PARPi was added to antiangiogenetics, compared to PARPi alone but a significant decrease in G3-G4 hypertension occurrence was found in PARPi plus bevacizumab users compared to Bevacizumab alone.

CONCLUSIONS

PARPi are a valid option for the treatment of both primary and relapsed OC patients, with a relative low incidence of severe side effects.

ENGOT-cx11/KEYNOTE-A18: A phase III, randomized, double-blind study of pembrolizumab with chemoradiotherapy in patients with high-risk locally advanced cervical cancer

TPS6096

Background: High-risk locally advanced cervical cancer has a poor prognosis, and more than half of patients recur in 2 y. External beam radiotherapy (EBRT) with concurrent chemotherapy followed by brachytherapy is the standard of care for locally advanced cervical cancer. The immunostimulatory activity of the PD-1 inhibitor pembrolizumab (pembro) may be enhanced by concurrent chemoradiotherapy (CRT). After the KEYNOTE-158 study, in which pembro showed durable antitumor activity, pembro monotherapy was approved for patients with PD-L1–positive recurrent or metastatic cervical cancer who progressed during or after chemotherapy. ENGOT-cx11/KEYNOTE-A18 (NCT04221945) is a phase III, randomized, placebo-controlled study evaluating pembro with concurrent CRT for the treatment of locally advanced cervical cancer. Methods: Approximately 980 patients with high-risk (FIGO 2014 stage IB2-IIB with node-positive disease or stage III-IVA), locally advanced, histologically confirmed cervical cancer who have not received systemic therapy, immunotherapy, definitive surgery, or radiation will be randomized 1:1 to receive either 5 cycles of pembro 200 mg every 3 wk (Q3W) + CRT followed by 15 cycles of pembro 400 mg Q6W or 5 cycles of placebo Q3W + CRT followed by 15 cycles of placebo Q6W. The CRT regimen includes 5 cycles (with optional 6th dose) of cisplatin 40 mg/m2 Q1W + EBRT followed by brachytherapy. Randomization is stratified by planned EBRT type (intensity-modulated radiotherapy [IMRT] or volumetric-modulated arc therapy [VMAT] vs non-IMRT or non-VMAT), cancer stage at screening (stage IB2-IIB vs III-IVA), and planned total radiotherapy dose. Treatment will continue until the patient has received 20 cycles of pembro (5 cycles 200 mg Q3W, 15 cycles 400 mg Q6W) vs placebo (~2 y) or until disease progression, unacceptable toxicity, or withdrawal. Primary endpoints are PFS per RECIST v1.1 by blinded independent central review and OS. Secondary endpoints are PFS at 2 y, OS at 3 y, complete response at 12 wk, ORR, PFS and OS in PD-L1–positive patients, EORTC QLQ-C30 and QLQ-CX24, and safety. Enrollment is ongoing. Clinical trial information: NCT04221945.

ENGOT-OV44/FIRST study: a randomized, double-blind, adaptive, phase III study of standard of care (SOC) platinum-based therapy ± dostarlimab followed by niraparib ± dostarlimab maintenance as first-line (1L) treatment of stage 3 or 4 ovarian cancer (OC)

TPS6101

Background: Despite surgery and CT (paclitaxel + carboplatin ± bevacizumab [bev]), 5-year survival rates remain low for patients (pts) with FIGO stage 3 or 4 OC. Niraparib is a poly (ADP-ribose) polymerase (PARP) inhibitor that has recently demonstrated efficacy in 1L therapy. Dostarlimab (TSR-042) is an anti-programmed death (PD)-1 humanized monoclonal antibody that has shown clinical activity as monotherapy in early phase trials. The currently enrolling ENGOT-OV44/FIRST study will compare efficacy and safety of CT + dostarlimab + niraparib ± bev (Arm 3) vs CT + niraparib ± bev (Arm 2). Methods: Eligible pts are ≥18 years of age, with FIGO stage 3 or 4 non-mucinous epithelial OC, ECOG performance status < 2, and tumor tissue available for PD-1 ligand (PD-L1) testing. After cycle 1 of CT, pts are stratified by concurrent bev use, BRCA mutation/homologous recombination repair status, and disease burden, then randomized 1:2 into trial Arms 2 and 3 (Table). Dostarlimab is administered at 500 mg IV Q3W during the CT period, then 1000 mg IV Q6W during the maintenance period. Niraparib dosing is 200 mg PO QD for pts with baseline bodyweight (BW) < 77 kg and/or platelet count (PC) < 150,000/µL, or 300 mg QD for pts with baseline BW ≥77 kg and PC ≥150,000/µL. The dual primary endpoints are PFS, based on investigator assessment per RECIST v1.1, in both PD-L1+ and all patients. Initially the study enrolled pts to Arm 1. This arm was discontinued following positive results from the PRIMA/ENGOT-OV26/GOG-3012 and PAOLA-1/ENGOT-OV25 studies. This allows investigators to offer the current standard of care to all patients. Clinical trial information: NCT03602859, EUDRACT 2018-000413-20. [Table: see text]

SIENDO/ENGOT-EN5: A randomized phase III trial of maintenance with selinexor/placebo after combination chemotherapy in patients with advanced or recurrent endometrial cancer

TPS6105

Background: Endometrial cancer is one of the most common gynecologic malignancies with increasing incidence and mortality. Patients with advanced disease that has relapsed or received prior platinum-based therapy or radiotherapy have limited options and the prognosis remains poor. Selinexor is a novel, oral selective inhibitor of nuclear export (SINE) which forces nuclear retention and activation of tumor suppressor proteins. Selinexor in combination with low dose dexamethasone was recently approved for patients with multiple myeloma. In addition, single agent selinexor has demonstrated broad activity in other hematologic malignancies and solid tumors. In a phase II study, 50 mg/m2 (~80 mg) selinexor administered twice weekly demonstrated a disease control rate of 35% with 2 confirmed partial responses among 23 patients with heavily pretreated endometrial cancer (Vergote I et al. Gynecol Oncol 2020). In the absence of approved maintenance therapies, we conducted this study to evaluate the efficacy of selinexor compared with placebo as maintenance therapy in patients with advanced or recurrent endometrial cancer. Methods: This is a multicenter, double-blind, placebo-controlled, randomized phase III study in patients in partial or complete remission after completing at least 12 weeks of taxane-platinum combination therapy for primary Stage IV disease and recurrent disease (i.e., relapse after primary therapy for early stage disease including surgery and/or adjuvant therapy). A total of 192 patients will be enrolled at 80 sites in Europe, North America, and Israel. Patients will be randomized in a 2:1 ratio to either maintenance therapy with 80 mg oral selinexor once weekly or placebo. Stratification factors include primary Stage IV versus first recurrent disease at the time of taxane-platinum therapy and disease status after chemotherapy (partial versus complete response). Treatment will continue until disease progression. The primary endpoint is progression free survival (PFS) per RECIST v1.1. Secondary endpoints include disease-specific survival, overall survival, time to first subsequent therapy, time to second subsequent therapy, PFS on subsequent therapy and safety and tolerability. The study is currently open and enrolling patients. Clinical trial information: NCT03555422.

Evaluation of an individualized starting-dose of niraparib in the PRIMA/ENGOT-OV26/GOG-3012 study

6050

Background: Niraparib is approved at a fixed starting dose (FSD) of 300 mg QD for maintenance treatment of patients (pts) with recurrent ovarian cancer (OC) achieving a complete or partial response to platinum-based chemotherapy based in the ENGOT-OV16/NOVA study. A post-hoc analysis of NOVA showed baseline bodyweight (BW) and platelet count (PC) were predictive for hematologic toxicities and dose reductions. Following this analysis, the PRIMA/ENGOT-OV26/GOG-3012 study was amended to prospectively evaluate the safety and efficacy of an individualized starting dose (ISD) regimen. Methods: This double-blind, placebo-controlled, phase III study randomized 733 pts with newly diagnosed advanced OC with a complete or partial response to first-line (1L) platinum-based chemotherapy. The protocol was amended to change the dose from 300 mg FSD for all patients to an ISD regimen: 200 mg QD in pts with BW <77 kg and/or PC <150,000/µL or 300 mg QD in pts with BW ≥77 kg and PC ≥150,000/µL. Exposure, efficacy, and safety data were compared between patients treated with FSD vs ISD. Results: Efficacy in the ISD subgroup was comparable to the FSD subgroup relative to placebo (Table). An interaction test showed no treatment difference between ISD and FSD at the pre-specified 0.10 significance level ( p=0.30). Medians for dose intensity and relative dose intensity in pts who received niraparib were similar. The overall safety profile among pts in the niraparib arm (n=484), including grade ≥3 hematologic toxicities, improved with the ISD. Conclusions: The ISD in the 1L maintenance setting provides comparable efficacy to the FSD while reducing the risk of hematologic toxicities. No new safety signals were identified. Clinical trial information: NCT02655016. [Table: see text]

Phase Ib/II trial of tisotumab vedotin (TV) ± bevacizumab (BEV), pembrolizumab (PEM), or carboplatin (CBP) in recurrent or metastatic cervical cancer (innovaTV 205/ENGOT-cx8/GOG-3024)

TPS6095

Background: Patients (pts) with recurrent/metastatic cervical cancer (r/mCC) receive paclitaxel/platinum or paclitaxel/topotecan ± BEV as first-line standard-of-care therapy. Tissue factor (TF) expression has been associated with poor prognosis in solid tumors, and TF is highly expressed in r/mCC. TV is an investigational antibody-drug conjugate composed of a fully human, TF-directed monoclonal antibody covalently attached to the microtubule-disrupting agent monomethyl auristatin E (MMAE) via a protease-cleavable linker. Upon internalization, MMAE is released resulting in cell cycle arrest and apoptotic cell death. In pts with previously treated r/mCC, TV monotherapy (IV 2.0 mg/kg Q3W) demonstrated a manageable safety profile and encouraging antitumor activity (investigator-assessed confirmed ORR, 24%; median DOR, 4.2 mo) [Hong DS et al. Clin Cancer Res. 2019. doi: 10.1158/1078-0432.CCR-19-2962]. The preliminary safety and efficacy data for TV monotherapy suggest a positive benefit/risk profile and warrant further investigation of TV in combination with therapies commonly administered to pts with r/mCC. The global, open-label, phase Ib/II trial innovaTV 205/ENGOT-cx8/GOG-3024 (NCT03786081) evaluates the safety and antitumor activity of TV monotherapy and TV in combination with BEV, PEM, or CBP in pts with untreated or previously treated r/mCC. This abstract presents the new TV monotherapy weekly dosing schedule. Results from this study will inform the further clinical development of TV in the treatment of r/mCC. Methods: Approximately 170 adult pts with recurrent or stage IVB squamous, adenosquamous, or adenocarcinoma of the cervix; measurable disease; and ECOG PS 0-1 will be enrolled. The phase I part of the study will consist of 3 dose-escalation arms for identification of the recommended phase II dose (RP2D) of TV administered Q3W with BEV, PEM, or CBP. In this part, previously treated pts will receive escalating doses of TV (IV Q3W) in combination with escalating doses of BEV (IV Q3W), a fixed dose of PEM (IV Q3W), or a fixed dose of CBP (IV Q3W). The phase II part will include 4 expansion arms. In this phase, pts who have not received prior systemic therapy for r/mCC will receive 1) TV RP2D + PEM or 2) TV RP2D + CBP; pts who received 1-2 prior treatments for r/mCC will receive 3) TV RP2D + PEM or 4) TV monotherapy with weekly dosing (IV 3Q4W). The primary endpoint of phase II is ORR by RECIST v1.1. Secondary endpoints include DOR, time to response, PFS, OS, and safety. Clinical trial information: NCT03786081.

ENGOT-EN6/NSGO-RUBY: A phase III, randomized, double-blind, multicenter study of dostarlimab + carboplatin-paclitaxel versus placebo + carboplatin-paclitaxel in recurrent or primary advanced endometrial cancer (EC)

TPS6107

Background: Carboplatin-paclitaxel is considered standard systemic anticancer therapy for recurrent or advanced EC for which surgery and/or radiation are not curative. Dostarlimab (TSR-042) is an anti-programmed cell death (PD)-1 humanized monoclonal antibody that has demonstrated antitumor activity and an acceptable safety profile in patients (pts) with recurrent or advanced EC in the GARNET trial. The RUBY trial was designed to evaluate the efficacy and safety of dostarlimab in combination with carboplatin-paclitaxel in recurrent or primary advanced EC compared with carboplatin-paclitaxel alone. Methods: This is a global, randomized, double-blind, multicenter, placebo-controlled study. Eligible pts must have first recurrent or primary stage III or stage IV EC with a low potential for cure by radiation therapy or surgery alone or in combination. Pts with carcinosarcoma are eligible for enrollment. 470 pts will be enrolled from approximately 160 sites in the ENGOT countries, United States, and Canada. Stratification factors are microsatellite instability (MSI) status (MSI-high [MSI-H] or microsatellite stable [MSS]), prior external pelvic radiotherapy (yes or no), and disease status (recurrent, primary stage III, or primary stage IV). Pts will be randomized 1:1 to receive combination dostarlimab 500 mg or placebo + carboplatin AUC 5 + paclitaxel 175 mg/m2 every 3 weeks for 6 cycles followed by dostarlimab 1000 mg or placebo monotherapy every 6 weeks for up to 3 years in the absence of progressive disease, death, unacceptable toxicity, or patient/physician decision to withdraw from the study. The primary endpoint is progression-free survival (PFS) as assessed by the investigator in the all-comers population and the MSI-H population per RECIST version 1.1. Secondary efficacy endpoints are PFS assessed by blinded independent central review per RECIST version 1.1, overall survival, objective response rate, duration of response, disease control rate, safety and tolerability, and patient-reported outcomes. Clinical trial information: NCT03981796.

Final survival analysis of NSGO-AVANOVA2/ENGOT-OV24: Combination of niraparib and bevacizumab versus niraparib alone as treatment of recurrent platinum-sensitive ovarian cancer—A randomized controlled chemotherapy-free study

6012

Background: We previously reported significantly improved progression-free survival (PFS) with the chemotherapy-free regimen of niraparib and bevacizumab compared to niraparib alone, in women with platinum-sensitive relapsed ovarian cancer (PSROC), regardless of homologous recombination deficiency (HRD) status (MyChoice HRD), duration of chemotherapy-free interval (CFI) and number of previous lines of therapy (Mirza MR et al, Lancet Oncol 2019). We now present the updated PFS, overall survival (OS) and other efficacy and safety endpoints. Methods: In this randomized, open-label, phase 2 study, women with measurable/evaluable, high-grade serous or endometrioid PSROC were randomized to niraparib 300mg once daily or the combination of niraparib 300mg once daily and bevacizumab 15mg/kg IV every 3 weeks until disease progression (1:1 randomization). The primary endpoint was PFS. Stratification was according to HRD status and CFI (6-12months (mo) vs. > 12mo). First-line maintenance bevacizumab was permitted. Results: Of 97 enrolled patients, 48 were randomized to niraparib monotherapy and 49 to the chemotherapy-free combination. The combined treatment significantly improved PFS compared to niraparib alone: updated median PFS 12.5 mo vs. 5.5 mo; hazard ratio (HR) adjusted for stratification factors 0.34; 95% confidence interval (CI) [0.21 to 0.55]; P < 0.0001. Preplanned exploratory subgroup analyses: patients with HRD-positive tumors (n = 54) HR 0.41 (CI, 0.23-0.76); HRD-negative disease (n = 43) HR, 0.40 (CI, 0.20-0.79); Time to First Subsequent Therapy (TFST) (n=97) HR, 0.4 (CI, 0.25-0.64); PFS2 (n=97) HR 0.55 (CI, 0.35-0.88); Time to Second Subsequent Therapy (TSST) (n=97) HR, 0.56 (CI, 0.35-0.90); OS (49 events only) HR, 0.77 (CI, 0.42-1.41). There was no difference in treatment-emergent grade 3-4 adverse events except for the rate of hypertension (22.9% vs. 0%) and neutropenia (8.3% vs. 2.0%). Patient-reported outcomes measured using EORTC QLQ-C30 and OV28 were similar for both treatment arms. Conclusions: Updated PFS consistently demonstrates that the niraparib-bevacizumab combination had clinically and statistically meaningful activity in PSROC. This phase 2 study was not powered to detect differences in OS or any other efficacy endpoints however TFST, PFS2 & TSST are significantly improved while there is a trend towards OS improvement with niraparib-bevacizumab combination. Clinical trial information: NCT02354131.