Detection of Residual Peritoneal Metastases Following Cytoreductive Surgery Using Pegsitacianine, a pH-Sensitive Imaging Agent: Final Results from a Phase II Study

BACKGROUND

For patients with peritoneal carcinomatosis, extent of disease and completeness of cytoreductive surgery (CRS) are major prognostic factors for long-term survival. Assessment of these factors could be improved using imaging agents. Pegsitacianine is a pH-sensitive polymeric micelle conjugated to the fluorophore indocyanine green. The micelle disassembles in acidic microenvironments, such as tumors, resulting in localized fluorescence unmasking. We assessed the utility of pegsitacianine in detecting residual disease following CRS.

PATIENTS AND METHODS

NCT04950166 was a phase II, non-randomized, open-label, multicenter US study. Patients eligible for CRS were administered an intravenous dose of pegsitacianine at 1 mg/kg 24-72 h before surgery. Following CRS, the peritoneal cavity was reexamined under near-infrared (NIR) illumination to evaluate for fluorescent tissue. Fluorescent tissue identified was excised and evaluated by histopathology. The primary outcome was the rate of clinically significant events (CSE), defined as detection of histologically confirmed residual disease excised with pegsitacianine or a revision in the assessment of completeness of CRS. Secondary outcomes included acceptable safety and pegsitacianine performance.

RESULTS

A total of 53 patients were screened, 50 enrolled, and 40 were evaluable for CSE across six primary tumor types. Residual disease was detected with pegsitacianine in 20 of 40 (50%) patients. Pegsitacianine showed high sensitivity and was well tolerated with no serious adverse events (SAEs). Transient treatment-related, non-anaphylactic infusion reactions occurred in 28% of patients.

CONCLUSIONS

Pegsitacianine was well tolerated and facilitated the recognition of occult residual disease following CRS. The high rate of residual disease detected suggests that the use of pegsitacianine augmented surgeon assessment and performance during CRS.

Phase 1b study of intraperitoneal ipilimumab and nivolumab in patients with recurrent gynecologic malignancies with peritoneal carcinomatosis

BACKGROUND

Intravenous immune checkpoint blockade (ICB) has shown poor response rates in recurrent gynecologic malignancies. Intraperitoneal (i.p.) ICB may result in enhanced T cell activation and anti-tumor immunity.

METHODS

In this phase 1b study, registered at Clinical.

TRIALS

gov (NCT03508570), initial cohorts received i.p. nivolumab monotherapy, and subsequent cohorts received combination i.p. nivolumab every 2 weeks and i.p. ipilimumab every 6 weeks, guided by a Bayesian design. The primary objective was determination of the recommended phase 2 dose (RP2D) of the combination. Secondary outcomes included toxicity, objective response rate (ORR), progression-free survival (PFS), and overall survival (OS).

FINDINGS

The trial enrolled 23 patients: 18 with ovarian cancer, 2 with uterine cancer, and 3 with cervical cancer. Study evaluable patients (n = 16) received a median of 2 prior lines of therapy (range: 1-8). Partial response was observed in 2 patients (12.5%; 1 ovarian, 1 uterine), and complete response was observed in 1 patient (6.3%) with cervical cancer, for an ORR of 18.8% (95% confidence interval: 4.0%-45.6%). The median duration of response was 14.8 months (range: 4.1-20.8), with one complete response ongoing. Median PFS and OS were 2.7 months and not reached, respectively. Grade 3 or higher immune-related adverse events occurred in 2 (8.7%) patients.

CONCLUSIONS

i.p. administration of dual ICB is safe and demonstrated durable responses in a subset of patients with advanced gynecologic malignancy. The RP2D is 3 mg/kg i.p. nivolumab every 2 weeks plus 1 mg/kg ipilimumab every 6 weeks.

FUNDING

This work was funded by Bristol Myers Squibb (CA209-9C7), an MD Anderson Cancer Center Support Grant (CA016672), the Ovarian Cancer Moon Shots Program, the Emerson Collective Fund, and a T32 training grant (CA101642).

Neuroendocrine neoplasms of the ovary: a review of 63 cases

OBJECTIVE

To describe the clinicopathological characteristics and survival outcomes of ovarian neuroendocrine neoplasms from a curated registry.

METHODS

This is a retrospective cross-sectional study of patients in our registry with confirmed ovarian neuroendocrine neoplasms. We excluded patients with small cell carcinoma not otherwise specified, small cell hypercalcemic type, and those with neuroendocrine 'features' or 'differentiation.' Clinicopathological characteristics were described in two separate groups: patients with carcinoid tumors and patients with neuroendocrine carcinomas. Progression-free and overall survival were estimated with the Kaplan-Meier product-limit estimator in these two groups, and multivariable analysis was done to identify predictors of survival for neuroendocrine carcinomas only.

RESULTS

A total of 63 patients met inclusion criteria, 13 (21%) with carcinoid tumors and 50 (79%) with neuroendocrine carcinomas. In the carcinoid tumor group, one patient (8%) was misdiagnosed. Two patients (15%) had a recurrence and the 5-year overall survival rate was 80% (95% CI 45% to 100%), with a lower bound of the median survival of 4.8 years (95% CI). In the neuroendocrine carcinoma group, 23 patients (46%) were misdiagnosed, 16 of whom (69%) received therapy with the presumption of a non-neuroendocrine carcinoma diagnosis. Thirty patients (60%) had a recurrence, and the 5-year overall survival rate was 24% (10%, 38%), with a median survival of 1.6 years (1.3, 3.3). Patients with carcinomas stage III or IV had an increased risk of progression/recurrence (HR=5.6; 95% CI 1.9 to 17.0) and death (HR=8.1; 95% CI 2.2 to 29.7) compared with those with stage I or II. Pure histology was associated with an increased risk of progression/recurrence (HR=2.3; 95% CI 1.0 to 5.2) compared with admixed histology.

CONCLUSION

Most patients had neuroendocrine carcinomas, which were associated with a higher recurrence rate and worse survival than carcinoid tumors. A high proportion of patients in both groups were initially misdiagnosed, and a new association with endometrial hyperplasia was observed. Neuroendocrine admixed histology is associated with a higher risk of progression.

Randomized phase 2 trial of tremelimumab and durvalumab in combination versus sequentially in recurrent platinum-resistant ovarian cancer

BACKGROUND

Single-agent immune checkpoint inhibitors (ICIs) have demonstrated limited responses in recurrent ovarian cancer; however, 30%-40% of patients achieve stable disease. The primary objective was to estimate progression-free survival (PFS) after sequential versus combination cytotoxic T-lymphocyte antigen 4 and programmed death ligand 1 ICIs in patients with platinum-resistant high-grade serous ovarian cancer (HGSOC).

METHODS

Patients were randomized to a sequential arm (tremelimumab followed by durvalumab on progression) or a combination arm (tremelimumab plus durvalumab, followed by durvalumab) via a Bayesian adaptive design that made it more likely for patients to be randomized to the more effective arm. The primary end point was immune-related PFS (irPFS).

RESULTS

Sixty-one subjects were randomized to sequential (n = 38) or combination therapy (n = 23). Thirteen patients (34.2%) in the sequential arm received durvalumab. There was no difference in PFS in the sequential arm (1.84 months; 95% CI, 1.77-2.17 months) compared with the combination arm (1.87 months; 95% CI, 1.77-2.43 months) (p = .402). In the sequential arm, no responses were observed, although 12 patients (31.6%) demonstrated stable disease. In the combination arm, two patients (8.7%) had partial response, whereas one patient (4.4%) had stable disease. Adverse events were consistent with those previously reported for ICIs. Patient-reported outcomes were similar in both arms.

CONCLUSIONS

There was no difference in irPFS for combination tremelimumab plus durvalumab compared to tremelimumab alone (administered as part of a sequential treatment strategy) in a heavily pretreated population of patients with platinum-resistant HGSOC. Response rates were comparable to prior reports, although the combination regimen did not add significant benefit, as has been previously described.

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.

Durvalumab Plus Carboplatin/Paclitaxel Followed by Maintenance Durvalumab With or Without Olaparib as First-Line Treatment for Advanced Endometrial Cancer: The Phase III DUO-E Trial

PURPOSE

Immunotherapy and chemotherapy combinations have shown activity in endometrial cancer, with greater benefit in mismatch repair (MMR)-deficient (dMMR) than MMR-proficient (pMMR) disease. Adding a poly(ADP-ribose) polymerase inhibitor may improve outcomes, especially in pMMR disease.

METHODS

This phase III, global, double-blind, placebo-controlled trial randomly assigned eligible patients with newly diagnosed advanced or recurrent endometrial cancer 1:1:1 to: carboplatin/paclitaxel plus durvalumab placebo followed by placebo maintenance (control arm); carboplatin/paclitaxel plus durvalumab followed by maintenance durvalumab plus olaparib placebo (durvalumab arm); or carboplatin/paclitaxel plus durvalumab followed by maintenance durvalumab plus olaparib (durvalumab + olaparib arm). The primary end points were progression-free survival (PFS) in the durvalumab arm versus control and the durvalumab + olaparib arm versus control.

RESULTS

Seven hundred eighteen patients were randomly assigned. In the intention-to-treat population, statistically significant PFS benefit was observed in the durvalumab (hazard ratio [HR], 0.71 [95% CI, 0.57 to 0.89]; P = .003) and durvalumab + olaparib arms (HR, 0.55 [95% CI, 0.43 to 0.69]; P < .0001) versus control. Prespecified, exploratory subgroup analyses showed PFS benefit in dMMR (HR [durvalumab v control], 0.42 [95% CI, 0.22 to 0.80]; HR [durvalumab + olaparib v control], 0.41 [95% CI, 0.21 to 0.75]) and pMMR subgroups (HR [durvalumab v control], 0.77 [95% CI, 0.60 to 0.97]; HR [durvalumab + olaparib v control] 0.57; [95% CI, 0.44 to 0.73]); and in PD-L1-positive subgroups (HR [durvalumab v control], 0.63 [95% CI, 0.48 to 0.83]; HR [durvalumab + olaparib v control], 0.42 [95% CI, 0.31 to 0.57]). Interim overall survival results (maturity approximately 28%) were supportive of the primary outcomes (durvalumab v control: HR, 0.77 [95% CI, 0.56 to 1.07]; P = .120; durvalumab + olaparib v control: HR, 0.59 [95% CI, 0.42 to 0.83]; P = .003). The safety profiles of the experimental arms were generally consistent with individual agents.

CONCLUSION

Carboplatin/paclitaxel plus durvalumab followed by maintenance durvalumab with or without olaparib demonstrated a statistically significant and clinically meaningful PFS benefit in patients with advanced or recurrent endometrial cancer.

EphA2- and HDAC-Targeted Combination Therapy in Endometrial Cancer

Endometrial cancer is the most frequent malignant tumor of the female reproductive tract but lacks effective therapy. EphA2, a receptor tyrosine kinase, is overexpressed by various cancers including endometrial cancer and is associated with poor clinical outcomes. In preclinical models, EphA2-targeted drugs had modest efficacy. To discover potential synergistic partners for EphA2-targeted drugs, we performed a high-throughput drug screen and identified panobinostat, a histone deacetylase inhibitor, as a candidate. We hypothesized that combination therapy with an EphA2 inhibitor and panobinostat leads to synergistic cell death. Indeed, we found that the combination enhanced DNA damage, increased apoptosis, and decreased clonogenic survival in Ishikawa and Hec1A endometrial cancer cells and significantly reduced tumor burden in mouse models of endometrial carcinoma. Upon RNA sequencing, the combination was associated with downregulation of cell survival pathways, including senescence, cyclins, and cell cycle regulators. The Axl-PI3K-Akt-mTOR pathway was also decreased by combination therapy. Together, our results highlight EphA2 and histone deacetylase as promising therapeutic targets for endometrial cancer.

Serial cytoreductive surgery and survival outcomes in recurrent adult-type ovarian granulosa cell tumors

BACKGROUND

Few studies have evaluated the role of cytoreductive surgery in patients with recurrent adult granulosa cell tumors of the ovary. Despite a multitude of treatment modalities in the recurrent setting, the optimal management strategy is not known. Cytoreductive surgery offers an attractive option for disease confined to the abdomen/pelvis. However, few studies have evaluated the role of surgery compared with systemic therapy alone following the first recurrence and subsequent disease progressions.

OBJECTIVE

This study aimed to determine the impact of secondary, tertiary, and quaternary cytoreductive surgery on survival outcomes in recurrent adult granulosa cell tumors of the ovary.

STUDY DESIGN

This is a multicenter, retrospective cohort study evaluating patients with recurrent adult granulosa cell tumors of the ovary enrolled in the MD Anderson Rare Gynecologic Malignancy Registry from 1970 to 2022. Study inclusion criteria consisted of histology-proven recurrent disease, at least 1 documented recurrence, and treatment/treatment planning at the MD Anderson Cancer Center or Lyndon B. Johnson General Hospital. The primary exposure was cytoreductive surgery, and the outcomes of interest were progression-free survival and overall survival. Survival analyses were restricted to eligible patients with resectable disease without medical barriers to surgery at each progression episode. Demographic and clinicopathologic characteristics were summarized using descriptive statistics. Progression-free survival (after first, second, and third progression) and overall survival were estimated with methods of Kaplan and Meier, and were modeled via Cox proportional hazards regression. Multivariable analyses were performed for progression-free survival after first progression and overall survival.

RESULTS

Among the 369 patients with adult granulosa cell tumors of the ovary in the registry, 149 patients met the study inclusion criteria. Secondary cytoreductive surgery was associated with a significant improvement in progression-free survival on univariable (hazard ratio, 0.37; 95% confidence interval, 0.17-0.81, P=.01) and multivariable analyses (hazard ratio, 0.42; 95% confidence interval, 0.19-0.92; P=.03). Those who underwent secondary cytoreductive surgery had a significantly improved median overall survival compared with those who did not undergo cytoreductive surgery (181.92 vs 61.56 months, respectively; P=.002). Overall survival benefit remained statistically significant on multivariable analysis (hazard ratio, 0.28; 95% confidence interval, 0.11-0.67; P=.004). Tertiary cytoreductive surgery was similarly associated with a significant improvement in progression-free survival (hazard ratio, 0.43; 95% confidence interval, 0.26-0.70; P=.001). Despite a similar trend, quaternary cytoreductive surgery was not associated with a significant improvement in progression-free survival (hazard ratio, 0.74; 95% confidence interval, 0.42-1.26; P=.27).

CONCLUSION

Among those with resectable disease and no medical contraindications to surgery, cytoreductive surgery may have a beneficial impact on progression-free survival and overall survival in patients with recurrent adult granulosa cell tumors of the ovary.

PRMT blockade induces defective DNA replication stress response and synergizes with PARP inhibition

Multiple cancers exhibit aberrant protein arginine methylation by both type I arginine methyltransferases, predominately protein arginine methyltransferase 1 (PRMT1) and to a lesser extent PRMT4, and by type II PRMTs, predominately PRMT5. Here, we perform targeted proteomics following inhibition of PRMT1, PRMT4, and PRMT5 across 12 cancer cell lines. We find that inhibition of type I and II PRMTs suppresses phosphorylated and total ATR in cancer cells. Loss of ATR from PRMT inhibition results in defective DNA replication stress response activation, including from PARP inhibitors. Inhibition of type I and II PRMTs is synergistic with PARP inhibition regardless of homologous recombination function, but type I PRMT inhibition is more toxic to non-malignant cells. Finally, we demonstrate that the combination of PARP and PRMT5 inhibition improves survival in both BRCA-mutant and wild-type patient-derived xenografts without toxicity. Taken together, these results demonstrate that PRMT5 inhibition may be a well-tolerated approach to sensitize tumors to PARP inhibition.

Transforming ovarian cancer care by targeting minimal residual disease

Frontline treatment and resultant cure rates in patients with advanced ovarian cancer have changed little over the past several decades. Here, we outline a multidisciplinary approach aimed at gaining novel therapeutic insights by focusing on the poorly understood minimal residual disease phase of ovarian cancer that leads to eventual incurable recurrences.

Low-grade serous ovarian cancer: expert consensus report on the state of the science

Compared with high-grade serous carcinoma, low-grade serous carcinoma of the ovary or peritoneum is a less frequent epithelial ovarian cancer type that is poorly sensitive to chemotherapy and affects younger women, many of whom endure years of ineffective treatments and poor quality of life. The pathogenesis of this disease and its management remain incompletely understood. However, recent advances in the molecular characterization of the disease and identification of novel targeted therapies with activity in low-grade serous carcinoma offer the promise of improved outcomes. To update clinicians regarding recent scientific and clinical trial advancements and discuss unanswered questions related to low-grade serous carcinoma diagnosis and treatment, a panel of experts convened for a workshop in October 2022 to develop a consensus document addressing pathology, translational research, epidemiology and risk, clinical management, and ongoing research. In addition, the patient perspective was discussed. The recommendations developed by this expert panel-presented in this consensus document-will guide practitioners in all settings regarding the clinical management of women with low-grade serous carcinoma and discuss future opportunities to improve research and patient care.

Quality-adjusted survival in women with gynecologic malignancies receiving IMRT after surgery: A Ppatient Rreported Ooutcome study of NRG oncology's RTOG 1203

INTRODUCTION

NRG/RTOG 1203 compared 3-D conformal radiotherapy (3D CRT) to intensity-modulated radiotherapy (IMRT) in patients with endometrial or cervical cancer requiring post-operative radiotherapy after hysterectomy. The purpose of this study was to report the first quality-adjusted survival analysis comparing the two treatments.

METHODS

NRG/RTOG 1203 randomized patients having undergone hysterectomy to either 3DCRT or IMRT. Stratification factors included RT dose, chemotherapy, and disease site. The EQ-5D, both index and visual analog scale (VAS), were obtained at baseline, 5 weeks after the start of RT, 4-6 weeks post RT and 1 and 3-years post RT. EQ-5D index and VAS scores along with quality-adjusted survival (QAS) were compared between treatment arms using the t-test at a two-sided significance level of 0.05.

RESULTS

NRG/RTOG 1203 enrolled 289 patients of which 236 consented to participate in the patient reported outcome (PRO) assessments. QAS was higher in women treated with IMRT, 1374 vs 1333 days (p = 0.5) compared to patients treated with 3DCRT, but this difference was not statistically different. Patients treated with IMRT had less of a decline in VAS score 5 weeks post RT, -5.04, compared to patients treated with 3DCRT, -7.48, although not statistically significant (p = 0.38).

CONCLUSION

This is the first report of the use of the EQ-5D comparing two radiotherapy techniques in the treatment of gynecologic malignancies after surgery. While there were no significant differences in QAS and VAS scores between patients who received IMRT vs. 3DCRT, RTOG 1203 was not powered to show statistical differences in these secondary endpoints.

Clinical implications of tumor-based next-generation sequencing in high-grade epithelial ovarian cancer

BACKGROUND

Tumor-based next-generation sequencing is used inconsistently as a tool to tailor treatment of ovarian cancer, yet beyond detection of somatic BRCA1 and BRCA2 mutations, the clinical benefit is not well established. This study aimed to assess the clinical relevance of tumor-based next-generation sequencing (tbNGS) in patients with ovarian cancer.

METHODS

This retrospective study included patients with high-grade epithelial ovarian carcinoma. tbNGS results were identified in the electronic medical record using optical character recognition and natural language processing. Genetic, clinical, and demographic information was collected. Progression-free survival (PFS) and overall survival were calculated and compared using log-rank tests. Multivariate Cox regression and clustering analyses were used to identify patterns of genetic alterations associated with survival.

RESULTS

Of 1092 patients in the described population, 409 (37.5%) had tbNGS results. Nearly all (96.1% [393/409]) had one or more genetic alterations. In 25.9% (106/409) of patients, an alteration that aligned with a targeted treatment was identified, and in an additional 48.7% (199/409), tbNGS results suggested eligibility for an investigational agent or clinical trial. The most frequent alterations were TP53, PIK3CA, and NF1 mutations, and CCNE1 amplification. Together, BRCA1 and BRCA2 mutations were associated with longer PFS (hazard ratio [HR], 0.62; 95% confidence interval [CI], 0.42-0.92; p = .02), whereas AKT2 amplification was associated with shorter PFS (HR, 3.86; 95% CI, 1.002-14.88; p < .05). Multivariate Cox regression and clustering analyses identified several combinations of genetic alterations that corresponded to outcomes in patients with high-grade serous carcinoma.

CONCLUSIONS

tbNGS often yields clinically relevant information. Detailed analysis of population-level tumor genomics may help to identify therapeutic targets and guide development of clinical decision support tools.

PLAIN LANGUAGE SUMMARY

Although more and more patients with ovarian cancer are undergoing tumor-based next-generation sequencing to identify genetic mutations in their tumors, the benefits of such testing are not well established. In a group of over 400 patients with ovarian cancer who underwent tumor-based next-generation sequencing in the course of their treatment, nearly all patients had one or more genetic alterations detected, and one out of four patients had a mutation that qualified them for a personalized treatment option.

Phase II Trial of MEDI0457 and Durvalumab for Patients With Recurrent/Metastatic Human Papillomavirus-Associated Cancers

BACKGROUND

Human papillomavirus (HPV) types 16/18 drive oncogenesis for most patients with cervical, anal, and penile cancers. MEDI0457, a therapeutic DNA vaccine containing plasmids for E6 and E7 HPV-16/18 viral oncogenes and IL-12 adjuvant, is safe and provokes an immune response against E6/E7. We tested MEDI0457 with the anti-PD-L1 antibody durvalumab for patients with HPV-associated cancers.

METHODS

Patients with recurrent/metastatic, treatment-refractory HPV-16/18 cervical cancer, or rare HPV-associated (anal and penile) cancers were eligible. Prior immune checkpoint inhibition was not permitted. Patients received MEDI0457 7 mg intramuscularly (weeks 1, 3, 7, 12, and every 8 weeks thereafter) and durvalumab 1500 mg intravenously every 4 weeks. The primary endpoint was overall response (RECIST 1.1). In this Simon two-stage phase 2 trial (Ho: p < 0.15; Ha: p ≥ 0.35), ≥2 responses were needed in both cervical and non-cervical cohorts during the first stage for the trial to proceed to stage 2 with an additional 25 patients (34 total) enrolled.

RESULTS

Twenty-one patients (12 cervical, 7 anal, and 2 penile) were evaluable for toxicity and 19 for response Overall response rate was 21% (95% CI, 6%-46%) among evaluable patients. Disease control rate was 37% (95% CI, 16%-62%). Median duration of response among responders was 21.8 months (95% CI, 9.7%-not estimable). Median progression-free survival was 4.6 months (95% CI, 2.8%-7.2%). Median overall survival was 17.7 months (95% CI, 7.6%-not estimable). Grades 3-4 treatment-related adverse events occurred in 6 (23%) participants.

CONCLUSIONS

The combination of MEDI0457 and durvalumab demonstrated acceptable safety and tolerability in patients with advanced HPV-16/18 cancers. The low ORR among patients with cervical cancer led to study discontinuation despite a clinically meaningful disease control rate.

Stranger Things: New Roles and Opportunities for Androgen Receptor in Oncology Beyond Prostate Cancer

The androgen receptor (AR) is one of the oldest therapeutic targets in oncology and continues to dominate the treatment landscape for advanced prostate cancer, where nearly all treatment regimens include some form of AR modulation. In this regard, AR remains the central driver of prostate cancer cell biology. Emerging preclinical and clinical data implicate key roles for AR in additional cancer types, thereby expanding the importance of this drug target beyond prostate cancer. In this mini-review, new roles for AR in other cancer types are discussed as well as their potential for treatment with AR-targeted agents. Our understanding of these additional functions for AR in oncology expand this receptor's potential as a therapeutic target and will help guide the development of new treatment approaches.

Multicenter Phase II Trial of the WEE1 Inhibitor Adavosertib in Refractory Solid Tumors Harboring CCNE1 Amplification

PURPOSE

Preclinical cancer models harboring CCNE1 amplification were more sensitive to adavosertib treatment, a WEE1 kinase inhibitor, than models without amplification. Thus, we conducted this phase II study to assess the antitumor activity of adavosertib in patients with CCNE1-amplified, advanced refractory solid tumors.

PATIENTS AND METHODS

Patients aged ≥ 18 years with measurable disease and refractory solid tumors harboring CCNE1 amplification, an Eastern Cooperative Oncology Group performance status of 0-1, and adequate organ function were studied. Patients received 300 mg of adavosertib once daily on days 1 through 5 and 8 through 12 of a 21-day cycle. The trial followed Bayesian optimal phase II design. The primary end point was objective response rate (ORR).

RESULTS

Thirty patients were enrolled. The median follow-up duration was 9.9 months. Eight patients had partial responses (PRs), and three had stable disease (SD) ≥ 6 months, with an ORR of 27% (95% CI, 12 to 46), a SD ≥ 6 months/PR rate of 37% (95% CI, 20 to 56), a median progression-free survival duration of 4.1 months (95% CI, 1.8 to 6.4), and a median overall survival duration of 9.9 months (95% CI, 4.8 to 15). Fourteen patients with epithelial ovarian cancer showed an ORR of 36% (95% CI, 13 to 65) and SD ≥ 6 months/PR of 57% (95% CI, 29 to 82), a median progression-free survival duration of 6.3 months (95% CI, 2.4 to 10.2), and a median overall survival duration of 14.9 months (95% CI, 8.9 to 20.9). Common treatment-related toxicities were GI, hematologic toxicities, and fatigue.

CONCLUSION

Adavosertib monotherapy demonstrates a manageable toxicity profile and promising clinical activity in refractory solid tumors harboring CCNE1 amplification, especially in epithelial ovarian cancer. Further study of adavosertib, alone or in combination with other therapeutic agents, in CCNE1-amplified epithelial ovarian cancer is warranted.

Clinical outcomes of leuprolide acetate in the treatment of recurrent ovarian granulosa cell tumors

BACKGROUND

The optimal treatment of recurrent ovarian granulosa cell tumors is not known. Pre-clinical studies and small case series have suggested direct anti-tumor activity of gonadotropin-releasing hormone agonists in the treatment of this disease, but little is known about the efficacy and safety of this approach.

OBJECTIVE

To describe patterns of use and clinical outcomes of leuprolide acetate in a cohort of patients with recurrent granulosa cell tumors.

STUDY DESIGN

This was a retrospective cohort study of patients enrolled in the Rare Gynecologic Malignancy Registry at a large cancer referral center and affiliated county hospital. Patients meeting inclusion criteria had a diagnosis of recurrent granulosa cell tumor and received either leuprolide acetate or traditional chemotherapy as cancer treatment. Outcomes were separately examined for leuprolide acetate used as adjuvant treatment, maintenance therapy, and the treatment of gross disease. Demographic and clinical data were summarized using descriptive statistics. Progression-free survival was calculated from the initiation of treatment to the date of disease progression or death, and compared between groups with the log-rank test. The 6-month clinical benefit rate was defined as the percentage of patients without disease progression 6 months after starting therapy.

RESULTS

Sixty-two patients received a total of 78 leuprolide acetate-containing therapy courses, owing to 16 instances of retreatment. Of these 78 courses, 57 (73%) were for treatment of gross disease, 10 (13%) were adjuvant to tumor reductive surgery, and 11 (14%) were for maintenance therapy. Patients had received a median of two (IQR, 1-3) systemic therapy regimens prior to their first leuprolide acetate treatment. Tumor reductive surgery (100% [62/62]) and platinum-based chemotherapy (81% [50/62]) were common prior to first leuprolide acetate exposure. The median duration of leuprolide acetate therapy was 9.6 months (IQR, 4.8-16.5 months). Nearly half of the therapy courses were single-agent leuprolide acetate (49% [38/78]). Combination regimens most often included an aromatase inhibitor (23% [18/78]). Disease progression was the most common cause of discontinuation (77% [60/78]); only one patient (1%) discontinued leuprolide acetate because of adverse events. In the treatment of gross disease, the 6-month clinical benefit rate for first use of leuprolide acetate was 66% (95% CI, 54-82%). Median progression-free survival was not statistically different compared to that which followed chemotherapy (10.3 months [95% CI, 8.0-16.0 months] vs. 8.0 months [95% CI, 5.0-15.3 months], p=0.3).

CONCLUSION

In a large cohort of patients with recurrent granulosa cell tumors, the 6-month clinical benefit rate of first-time leuprolide acetate treatment of gross disease was 66% and progression-free survival was comparable to patients treated with chemotherapy. Leuprolide acetate regimens were heterogeneous, but significant toxicity was rare. These results support leuprolide acetate as safe and effective for the treatment of relapsed adult granulosa cell tumors in the second line and beyond.

Exploiting metabolic vulnerabilities after anti-VEGF antibody therapy in ovarian cancer

Despite modest clinical improvement with anti-vascular endothelial growth factor antibody (AVA) therapy in ovarian cancer, adaptive resistance is ubiquitous and additional options are limited. A dependence on glutamine metabolism, via the enzyme glutaminase (GLS), is a known mechanism of adaptive resistance and we aimed to investigate the utility of a GLS inhibitor (GLSi). Our in vitro findings demonstrated increased glutamine abundance and a significant cytotoxic effect in AVA-resistant tumors when GLSi was administered in combination with bevacizumab. In vivo, GLSi led to a reduction in tumor growth as monotherapy and when combined with AVA. Furthermore, GLSi initiated after the emergence of resistance to AVA therapy resulted in a decreased metabolic conversion of pyruvate to lactate as assessed by hyperpolarized magnetic resonance spectroscopy and demonstrated robust antitumor effects with a survival advantage. Given the increasing population of patients receiving AVA therapy, these findings justify further development of GLSi in AVA resistance.

Combination of EphA2- and Wee1-Targeted Therapies in Endometrial Cancer

EphA2 tyrosine kinase is upregulated in many cancers and correlated with poor survival of patients, including those with endometrial cancer. EphA2-targeted drugs have shown modest clinical benefit. To improve the therapeutic response to such drugs, we performed a high-throughput chemical screen to discover novel synergistic partners for EphA2-targeted therapeutics. Our screen identified the Wee1 kinase inhibitor, MK1775, as a synergistic partner to EphA2, and this finding was confirmed using both in vitro and in vivo experiments. We hypothesized that Wee1 inhibition would sensitize cells to EphA2-targeted therapy. Combination treatment decreased cell viability, induced apoptosis, and reduced clonogenic potential in endometrial cancer cell lines. In vivo Hec1A and Ishikawa-Luc orthotopic mouse models of endometrial cancer showed greater anti-tumor responses to combination treatment than to either monotherapy. RNASeq analysis highlighted reduced cell proliferation and defective DNA damage response pathways as potential mediators of the combination's effects. In conclusion, our preclinical findings indicate that Wee1 inhibition can enhance the response to EphA2-targeted therapeutics in endometrial cancer; this strategy thus warrants further development.

Predictors of Oncologic Outcome in Patients Receiving Phase I Investigational Therapy for Recurrent or Metastatic Cervical Cancer

Introduction

We aimed to identify clinical, pathologic, and treatment factors that are predictive of response and survival in patients with cervical cancer referred to phase I clinical trials.

Methods

Patients with cervical cancer who received at least one dose of a phase I investigational agent at our institution between 2014 and 2022 were included. The log-rank test was used to analyze differences in progression-free survival (PFS) and overall survival (OS), and multivariable regression analysis was performed.

Results

We included 65 patients with a median age of 41 years (range, 20-74), 3 prior therapies (range, 1-7), and 67.7% squamous carcinoma. The rate of distant metastasis at trial entry was 84.6%. The most common molecular alterations included PIK3CA (46.5%), PD-L1+ (46.2%), EPH (30.0%), and CREBBP (23.1%); 23.1% had received a prior checkpoint inhibitor. Phase I trials were for immunotherapy (58.5%) or targeted therapy (41.5%). The rate of biomarker matching was 21.5%. For all patients, median PFS was 3.6 months (95% CI, 2.0-5.2) and OS was 9.3 months (95% CI, 7.0-10.6). Factors at study entry associated with worse survival were presence of bone metastasis (PFS 1.6 vs 4.4 months: hazard ratio [HR], 2.8; p = 0.001; OS 3.8 vs 10.0 months: HR, 3.9; p < 0.0001) and absolute lymphocyte count below 1000/μL (PFS 1.8 vs 5.2 months: HR, 2.9; p = 0.0004; OS 7.0 vs 10.6 months: HR, 3.2; p = 0.0009). Factors associated only with worse OS were absolute neutrophil count above 4700/μL, hemoglobin below 10.5 g/dL, and smoking status. Grade 3+ treatment-related adverse events were seen in 16.9% of cases.

Conclusion

Bone metastasis and absolute lymphocyte count below normal range at phase I study entry portend poor survival in patients with recurrent or metastatic cervical cancer.

Selinexor in combination with weekly paclitaxel in patients with metastatic solid tumors: Results of an open label, single-center, multi-arm phase 1b study with expansion phase in ovarian cancer

OBJECTIVE

Selinexor is a first-in-class, oral selective inhibitor of nuclear export (SINE) compound which blocks Exportin-1 (XPO1). Our objective was to determine maximum tolerated dose (MTD) and recommended phase II dose (RP2D) of selinexor and weekly paclitaxel.

METHODS

This was an open label, single-center, multi-arm phase 1b study utilizing a "3 + 3" design and a "basket-type" expansion in recurrent solid tumors. Selinexor (60 mg or 80 mg twice weekly orally) and weekly paclitaxel (80 mg IV 2 week on, 1 week off) were one of 13 parallel arms. Efficacy was evaluated using RECIST version 1.1.

RESULTS

All 35 patients treated were evaluable for toxicity and 31 (88%) were evaluable for response. Patient diagnoses included platinum-resistant/refractory ovarian (n = 28), breast (n = 4), prostate (n = 2), and cervical (n = 1) cancer. Patients had a median of four prior therapies (range 1-10), and 47% had a prior taxane in the recurrent setting. There were no DLTs and 60 mg was chosen as the RP2D due to long-term tolerability. Ninety-seven percent of patients had at least one treatment-emergent adverse event (TEAE), and the most common grade ≥ 3 TEAE were neutropenia (46%), anemia (31%), and nausea (21%). Among 24 evaluable patients with ovarian cancer, response rate was 17%, CBR was 58%, and median PFS was 6.8 months (95% CI 3.7, not reached (NR)).

CONCLUSIONS

Oral selinexor in combination with weekly paclitaxel demonstrated promising clinical activity with manageable toxicity. This combination should be considered for further exploration in a randomized study, especially in ovarian malignancies.

Clinical Application of Poly(ADP-Ribose) Polymerase (PARP) Inhibitors in Ovarian Cancer

The treatment of ovarian cancer has remained a clinical challenge despite high rates of initial response to platinum-based chemotherapy. Patients are generally diagnosed at an advanced stage with significant disease burden, which portends to worse survival outcomes. Deficiencies in the homologous recombination (HRD) DNA damage repair (DDR) pathway and mutations in the BRCA1/2 genes have been found in ovarian carcinomas. Moreover, patients with these specific molecular aberrations have demonstrated sensitivity and thus improved response to poly(ADP-ribose) polymerase inhibitor (PARPi) treatment. The results of various clinical trials exploring the use of PARPi in different populations of ovarian cancer patients have shown impressive survival and response outcomes. With expanding indications, the use of PARPi has thus changed the landscape of ovarian cancer treatment. In this chapter, we will describe the different settings of PARPi treatment-frontline maintenance therapy, maintenance therapy for patients with recurrent platinum-sensitive disease, and treatment in the recurrent setting-and discuss treatment considerations and management of toxicities, as well as offer thoughts on future directions.

Adjuvant therapy in women with early stage uterine serous carcinoma: A multi-institutional study

OBJECTIVE

Uterine serous carcinoma is a rare but aggressive subtype of endometrial adenocarcinoma. Our objective was to compare adjuvant treatment strategies for patients with early stage uterine serous carcinoma.

METHODS

This multi-institutional, retrospective cohort study evaluated patients with early stage uterine serous carcinoma. Patients with FIGO Stage IA-II disease after surgery, whose tumors had serous or any mixed serous/non-serous histology were included. Patients with carcinosarcoma were excluded. Clinical data were abstracted from local medical records. Summary statistics, Fisher's exact, and Kruskal-Wallis tests were used to analyze demographic and clinical characteristics. Univariable and multivariable analyses were performed for recurrence-free and overall survival.

RESULTS

There were 737 patients included. Most patients had Stage IA disease (75%), 49% of which had no myometrial invasion. Only 164 (24%) tumors had lymphatic/vascular space invasion. Adjuvant treatment varied: 22% received no adjuvant therapy, 17% had chemotherapy alone, 19% had cuff brachytherapy, 35% had cuff brachytherapy with chemotherapy, and 6% underwent pelvic radiation. Adjuvant treatment was significantly associated with a decreased risk of recurrence (p = 0.04). Compared with no adjuvant therapy, patients who received brachytherapy or brachytherapy/chemotherapy had improved recurrence-free survival (HR 0.59, 95% CI 0.40-0.86; HR 0.65, 95% CI 0.49-0.88, respectively) and overall survival (HR 0.53, 95% CI 0.35-0.79; HR 0.49, 95% CI 0.35-0.69, respectively). Improved survival with brachytherapy and brachytherapy/chemotherapy persisted on multivariable analyses. Chemotherapy alone was also associated with improved overall survival compared with no adjuvant treatment (HR 0.55, 95% CI 0.37-0.81).

CONCLUSIONS

Adjuvant therapy was associated with a decreased risk of recurrence relative to observation alone. Adjuvant cuff brachytherapy with and without chemotherapy was associated with improved survival outcomes in patients with early stage uterine serous carcinoma.

A Randomized, Phase III Trial to Evaluate Rucaparib Monotherapy as Maintenance Treatment in Patients With Newly Diagnosed Ovarian Cancer (ATHENA-MONO/GOG-3020/ENGOT-ov45)

PURPOSE

ATHENA (ClinicalTrials.gov identifier: NCT03522246) was designed to evaluate rucaparib first-line maintenance treatment in a broad patient population, including those without BRCA1 or BRCA2 (BRCA) mutations or other evidence of homologous recombination deficiency (HRD), or high-risk clinical characteristics such as residual disease. We report the results from the ATHENA-MONO comparison of rucaparib versus placebo.

METHODS

Patients with stage III-IV high-grade ovarian cancer undergoing surgical cytoreduction (R0/complete resection permitted) and responding to first-line platinum-doublet chemotherapy were randomly assigned 4:1 to oral rucaparib 600 mg twice a day or placebo. Stratification factors were HRD test status, residual disease after chemotherapy, and timing of surgery. The primary end point of investigator-assessed progression-free survival was assessed in a step-down procedure, first in the HRD population (BRCA-mutant or BRCA wild-type/loss of heterozygosity high tumor), and then in the intent-to-treat population.

RESULTS

As of March 23, 2022 (data cutoff), 427 and 111 patients were randomly assigned to rucaparib or placebo, respectively (HRD population: 185 v 49). Median progression-free survival (95% CI) was 28.7 months (23.0 to not reached) with rucaparib versus 11.3 months (9.1 to 22.1) with placebo in the HRD population (log-rank P = .0004; hazard ratio [HR], 0.47; 95% CI, 0.31 to 0.72); 20.2 months (15.2 to 24.7) versus 9.2 months (8.3 to 12.2) in the intent-to-treat population (log-rank P < .0001; HR, 0.52; 95% CI, 0.40 to 0.68); and 12.1 months (11.1 to 17.7) versus 9.1 months (4.0 to 12.2) in the HRD-negative population (HR, 0.65; 95% CI, 0.45 to 0.95). The most common grade ≥ 3 treatment-emergent adverse events were anemia (rucaparib, 28.7% v placebo, 0%) and neutropenia (14.6% v 0.9%).

CONCLUSION

Rucaparib monotherapy is effective as first-line maintenance, conferring significant benefit versus placebo in patients with advanced ovarian cancer with and without HRD.

Targeting the PI3K Pathway in Gynecologic Malignancies

PURPOSE OF REVIEW

This review explores the PI3K pathway aberrations common in gynecologic malignancies, the relevant therapeutic targets that have been explored to date particularly given their success in endometrial cancers, and predictive biomarkers of response to therapy.

RECENT FINDINGS

Landmark trials have been noted involving this pathway, particularly in endometrial cancers. One phase II trial of the potent orally bioavailable mTOR inhibitor, everolimus, in combination with letrozole demonstrated an unprecedented clinical benefit rate (CBR) of 40% and high objective response rate (RR) of 32% in hormone agnostic endometrial cancers. This was followed by GOG 3007 that compared everolimus and letrozole to hormonal therapy yielding similar response rates but double progression-free survival rates. The phosphoinositide 3-kinase (PI3K) signaling pathway is implicated in tumorigenesis given its regulation over cell growth, cellular trafficking, and angiogenesis. In gynecologic malignancies, alterations in PI3K signaling are common. Therefore, developing modulators of the PI3K pathway and identifying molecular markers to predict response are of great interest for these cancer types.

Contemporary primary treatment of women with stage II-IV low-grade serous ovarian/peritoneal cancer (LGSOC): Determinants of relapse and disease-free survival

OBJECTIVE

The purpose of the present study is to describe a cohort who received contemporary primary treatment for stage II-IV low-grade serous ovarian/peritoneal cancer (LGSOC), including patient characteristics and determinants of relapse and disease-free survival.

METHODS

The study included 99 patients: 1) with pathologically confirmed stage II-IV LGSOC of the ovary or peritoneum, 2) who underwent primary treatment consisting of cytoreductive surgery and either a) platinum/taxane chemotherapy followed by aromatase inhibitor maintenance therapy or b) aromatase inhibitor monotherapy, and 3) for whom there was availability of clinical data. Descriptive statistics were used to characterize clinicodemographic features. Subgroups were compared for PFS and OS. Multivariable Cox regression analyses were performed.

RESULTS

Median PFS for the entire cohort was 56.8 months (95% CI, 41.3-NE), and median OS was 130.7 months (95% CI, 115.0-146.4). Forty-nine of 99 (49.5%) patients have relapsed to date. For these 49 patients, median time from diagnosis to relapse was 29.6 months (95% CI, 24.6-33.1) (range, 5.4-69.1 months). Only 1/49 (2%) patients who relapsed did so >5 years from diagnosis. Fifty (50.0%) patients have not experienced disease progression or relapse. Median follow-up time for these 50 patients is 86.2 months (range, 25.3-169.0). Thirty-three of the 50 (66.0%) have been followed for >5 years from diagnosis. On regression analyses, factors associated with improved patient outcomes-either PFS, OS, or both-included no gross residual disease, normal serum CA 125 at diagnosis, primary peritoneal site, and presence of extensive psammomatous calcifications.

CONCLUSIONS

This is the first report to describe the clinicopathologic features and outcomes of women with stage II-IV LGSOC who received contemporary primary therapy.

Classification of High-Grade Serous Ovarian Cancer Using Tumor Morphologic Characteristics

IMPORTANCE

Despite similar histologic appearance among high-grade serous ovarian cancers (HGSOCs), clinical observations suggest vast differences in gross appearance. There is currently no systematic framework by which to classify HGSOCs according to their gross morphologic characteristics.

OBJECTIVE

To develop and characterize a gross morphologic classification system for HGSOC.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study included patients with suspected advanced-stage ovarian cancer who presented between April 1, 2013, and August 5, 2016, to the University of Texas MD Anderson Cancer Center, a large referral center. Patients underwent laparoscopic assessment of disease burden before treatment and received a histopathologic diagnosis of HGSOC. Researchers assigning morphologic subtype and performing molecular analyses were blinded to clinical outcomes. Data analysis was performed between April 2020 and November 2021.

EXPOSURES

Gross tumor morphologic characteristics.

MAIN OUTCOMES AND MEASURES

Clinical outcomes and multiomic profiles of representative tumor samples of type I or type II morphologic subtypes were compared.

RESULTS

Of 112 women (mean [SD] age 62.7 [9.7] years) included in the study, most patients (84% [94]) exhibited a predominant morphologic subtype and many (63% [71]) had a uniform morphologic subtype at all involved sites. Compared with those with uniform type I morphologic subtype, patients with uniform type II morphologic subtype were more likely to have a favorable Fagotti score (83% [19 of 23] vs 46% [22 of 48]; P = .004) and thus to be triaged to primary tumor reductive surgery. Similarly, patients with uniform type II morphologic subtype also had significantly higher mean (SD) estimated blood loss (639 [559; 95% CI, 391-887] mL vs 415 [527; 95% CI, 253-577] mL; P = .006) and longer mean (SD) operative time (408 [130; 95% CI, 350-466] minutes vs 333 [113; 95% CI, 298-367] minutes; P = .03) during tumor reductive surgery. Type I tumors had enrichment of epithelial-mesenchymal transition (false discovery rate [FDR] q-value, 3.10 × 10-24), hypoxia (FDR q-value, 1.52 × 10-5), and angiogenesis pathways (FDR q-value, 2.11 × 10-2), whereas type II tumors had enrichment of pathways related to MYC signaling (FDR q-value, 2.04 × 10-9) and cell cycle progression (FDR q-value, 1.10 × 10-5) by integrated proteomic and transcriptomic analysis. Abundances of metabolites and lipids also differed between the 2 morphologic subtypes.

CONCLUSIONS AND RELEVANCE

This study identified 2 novel, gross morphologic subtypes of HGSOC, each with unique clinical features and molecular signatures. The findings may have implications for triaging patients to surgery or chemotherapy, identifying outcomes, and developing tailored therapeutic strategies.

Targeting the ALK-CDK9-Tyr19 kinase cascade sensitizes ovarian and breast tumors to PARP inhibition via destabilization of the P-TEFb complex

Poly(ADP-ribose) polymerase (PARP) inhibitors have demonstrated promising clinical activity in multiple cancers. However, resistance to PARP inhibitors remains a substantial clinical challenge. In the present study, we report that anaplastic lymphoma kinase (ALK) directly phosphorylates CDK9 at tyrosine-19 to promote homologous recombination (HR) repair and PARP inhibitor resistance. Phospho-CDK9-Tyr19 increases its kinase activity and nuclear localization to stabilize positive transcriptional elongation factor b and activate polymerase II-dependent transcription of HR-repair genes. Conversely, ALK inhibition increases ubiquitination and degradation of CDK9 by Skp2, an E3 ligase. Notably, combination of US Food and Drug Administration-approved ALK and PARP inhibitors markedly reduce tumor growth and improve survival of mice in PARP inhibitor-/platinum-resistant tumor xenograft models. Using human tumor biospecimens, we further demonstrate that phosphorylated ALK (p-ALK) expression is associated with resistance to PARP inhibitors and positively correlated with p-Tyr19-CDK9 expression. Together, our findings support a biomarker-driven, combinatorial treatment strategy involving ALK and PARP inhibitors to induce synthetic lethality in PARP inhibitor-/platinum-resistant tumors with high p-ALK-p-Tyr19-CDK9 expression.

Intensity-Modulated Radiation Therapy Reduces Patient-Reported Chronic Toxicity Compared With Conventional Pelvic Radiation Therapy: Updated Results of a Phase III Trial

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned coprimary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported.The purpose of this update was to determine differences in patient-reported chronic toxicity and disease outcomes with intensity-modulated radiation therapy (IMRT) compared with conventional pelvic radiation. Patients with cervical and endometrial cancers who received postoperative pelvic radiation were randomly assigned to conventional radiation therapy (CRT) or IMRT. Toxicity and quality of life were assessed using Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events, Expanded Prostate Cancer Index Composite (EPIC) bowel and urinary domains, and Functional Assessment of Cancer Therapy-General. Between 2012 and 2015, 279 eligible patients were enrolled to the study with a median follow-up of 37.8 months. There were no differences in overall survival (P = .53), disease-free survival (P = .21), or locoregional failure (P = .81). One year after RT, patients in the CRT arm experienced more high-level diarrhea frequency (5.8% IMRT v 15.1% CRT, P = .042) and a greater number had to take antidiarrheal medication two or more times a day (1.2% IMRT v 8.6% CRT, P = .036). At 3 years, women in the CRT arm reported a decline in urinary function, whereas the IMRT arm continued to improve (mean change in EPIC urinary score = 0.5, standard deviation = 13.0, IMRT v -6.0, standard deviation = 14.3, CRT, P = .005). In conclusion, IMRT reduces patient-reported chronic GI and urinary toxicity with no difference in treatment efficacy at 3 years.

Targeting the DNA damage response beyond poly(ADP-ribose) polymerase inhibitors: novel agents and rational combinations

PURPOSE OF REVIEW

Poly(ADP-ribose) polymerase (PARP) inhibitors have transformed treatment paradigms in multiple cancer types defined by homologous recombination deficiency (HRD) and have become the archetypal example of synthetic lethal targeting within the DNA damage response (DDR). Despite this success, primary and acquired resistance to PARP inhibition inevitability threaten the efficacy and durability of response to these drugs. Beyond PARP inhibitors, recent advances in large-scale functional genomic screens have led to the identification of a steadily growing list of genetic dependencies across the DDR landscape. This has led to a wide array of novel synthetic lethal targets and corresponding inhibitors, which hold promise to widen the application of DDR inhibitors beyond HRD and potentially address PARP inhibitor resistance.

RECENT FINDINGS

In this review, we describe key synthetic lethal interactions that have been identified across the DDR landscape, summarize the early phase clinical development of the most promising DDR inhibitors, and highlight relevant combinations of DDR inhibitors with chemotherapy and other novel cancer therapies, which are anticipated to make an impact in rationally selected patient populations.

SUMMARY

The DDR landscape holds multiple opportunities for synthetic lethal targeting with multiple novel DDR inhibitors being evaluated on early phase clinical trials. Key challenges remain in optimizing the therapeutic window of ATR and WEE1 inhibitors as monotherapy and in combination approaches.

Molecular Profiles of Serum-Derived Extracellular Vesicles in High-Grade Serous Ovarian Cancer

Patients with high-grade serous ovarian cancer (HGSC) who have no visible residual disease (R0) after primary surgery have the best clinical outcomes, followed by patients who undergo neoadjuvant chemotherapy (NACT) and have a response enabling interval cytoreductive surgery. Clinically useful biomarkers for predicting these outcomes are still lacking. Extracellular vesicles (EVs) have been recognized as liquid biopsy-based biomarkers for early cancer detection and disease surveillance in other disease settings. In this study, we performed extensive molecular characterization of serum-derived EVs and correlated the findings with therapeutic outcomes in patients with HGSC. Using EV-DNA whole-genome sequencing and EV-RNA sequencing, we identified distinct somatic EV-DNA alterations in cancer-hallmark genes and in ovarian cancer genes, as well as significantly altered oncogenic pathways between the R0 group and NACT groups. We also found significantly altered EV-RNA transcriptomic variations and enriched pathways between the groups. Taken together, our data suggest that the molecular characteristics of EVs could enable prediction of patients with HGSC who could undergo R0 surgery or respond to chemotherapy.

Abstract 2484: Hyperpolarized magnetic resonance spectroscopy assessment of the metabolic effects of glutaminase inhibitor therapy in an ovarian cancer model

Introduction: Ovarian cancer accounts for more deaths than any other cancer of the female reproductive system despite advances in targeted drugs such as anti-VEGF antibody (AVA). Additionally, resistance to AVA therapy is nearly ubiquitous given the occurrence of metabolic adaptations such as a dependence on glutamine metabolism via the enzyme glutaminase.

Objectives: To examine the metabolic vulnerability of AVA-resistant cancer with glutaminase inhibitor (GLSi) therapy and to test the utility of hyperpolarized magnetic resonance spectroscopy (HP-MRS) for assessing changes in lactate metabolism associated with GLSi treatment following injection of hyperpolarized [1-13C] pyruvate.

Methods: We used a well-characterized SKOV3ip1 orthotopic mouse model of high-grade serous ovarian cancer with adaptive resistance to AVA (bevacizumab) treatment. Following three weeks of GLSi and bevacizumab treatment, we performed HP-MRS imaging to directly and non-invasively compare metabolic changes between the treatment groups of bevacizumab monotherapy versus a combined treatment of bevacizumab plus GLSi therapy. Upon injection of hyperpolarized [1-13C] pyruvate, we quantitatively assessed a normalized lactate ratio (nLac), defined as the 13C resonance signal of lactate divided by the sum of the pyruvate and lactate signals, sixty seconds after injection. GLSi treatment effect was subsequently compared between GLSi monotherapy, bevacizumab monotherapy and control mice receiving no therapy. This was performed via gross necropsy to assess disease burden and quantification of tumor weight and nodule number.

Results: Significance analysis microarrays (SAM) of bevacizumab treated tumors from the mouse models revealed greater glutamine and glutamate abundance in all tissues suggestive of a glutamine dependence in AVA resistant tumors that could be susceptible to glutaminase inhibition. The in vivo HP-MRS provided a direct and non-invasive investigation of pyruvate metabolism of tumors in situ. Our analysis indicated that the pyruvate-to-lactate conversion was significantly reduced in vivo by GLSi treatment (0.337 vs 0.178, p=0.0002), suggestive of therapeutic efficacy of GLSi in the setting of AVA-resistant tumors. Consistent with this, we observed a statistically significant reduction in tumor weight (0.05g vs 0.62g and 0.64g, p&lt;0.01) and tumor nodule number (n=3.3 vs n=12.8 and n=13.9, p&lt;0.05) in mice treated with a combination of bevacizumab and GLSi compared to the control group, or GLSi monotherapy, respectively.

Conclusions: Using HP-MRS in vivo, we directly monitored metabolic changes occurring after GLSi treatment. These findings are consistent with the notion of glutamine dependence being an important resistance mechanism to AVA therapy and imply potential future use of HP-MRS in monitoring therapeutic efficacy in a clinical realm.

Citation Format: Deanna Glassman, Mark S. Kim, Prasanta Dutta, Charles V. Kingsley, Emine Bayraktar, Yutuan Wu, Elaine Stur, Lingegowda S. Mangala, Katherine Foster, Sanghoon Lee, Timothy A. Yap, Shannon N. Westin, Pratip Bhattacharya, Anil K. Sood. Hyperpolarized magnetic resonance spectroscopy assessment of the metabolic effects of glutaminase inhibitor therapy in an ovarian cancer model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2484.

Abstract 5106: Distinct molecular profiles of serum-derived extracellular vesicles in high-grade serous ovarian cancer

Background: Patients with high-grade serous ovarian cancer (HGSC) who have no visible residual disease (CGR) after primary surgery have the best clinical outcomes, followed by patients who undergo neoadjuvant chemotherapy (NACT) and have response enabling interval cytoreductive surgery. Through comprehensive omics analyses, we previously characterized molecular and cellular profiles of highly clinically defined HGSC from patients who had CGR versus those triaged to NACT. However, clinically useful predictive biomarkers for such distinctions are still lacking. Extracellular vesicles (EVs) have been recognized as liquid biopsy-based biomarkers for early cancer detection and disease surveillance in other disease settings. Here, we performed extensive molecular characterization of serum-derived EVs and correlated them with therapeutic outcomes in patients with HGSC.

Methods: Serum-derived medium/large size EVs from patients with HGSC treated under a systematic surgical algorithm were isolated following standard methods of the International Society for Extracellular Vesicles. Patients had either complete gross resection after primary surgery (R0, n=3); poor response to NACT (NACT-PR, n=4), or excellent response to NACT with carboplatin and paclitaxel (NACT-ER, n=3); tissue and matched germline blood samples have already been comprehensively analyzed (Lee et al, Cell Reports, 2020). The isolated EV-DNA and EV-RNA were subjected to whole-genome sequencing and RNA sequencing, respectively.

Results: We identified somatic EV-DNA alterations in cancer hallmark genes, including FAT1 and KMT2D as the most frequent mutated genes. Interestingly, we found alterations in ovarian cancer-related genes, including BRCA2 and RAD51 in R0; BRCA2 in NACT-ER; TP53, CDK13, CDK12, BRAF, AKT2, and ARID1A in NACT-PR patients. We also identified 26,338 genes expressed in the EV-RNA transcriptomic profiles. The analysis of the enrichment of cancer hallmark pathways showed that the R0 group was more enriched in the interferon α/γ, PI3K/AKT/mTOR signaling, and DNA repair pathways. Interestingly, we also identified 6,757 differentially expressed genes (DEGs) in the CGR versus the NACT groups (absolute log2-fold change ≥2 and adjusted p-value &lt;0.05). Among the DEGs, we identified 67 genes that were cancer hallmark genes, and 21 of them were overexpressed in the NACT group and 46 were overexpressed in the R0 group. Noticeably, 11 DEGs were directly related to ovarian cancer: TP53, PTEN, CCND1, BARD1, PMS2, and MLH3 were significantly overexpressed in the NACT group, while BRCA2, CSMD3, and GABRA6 were overexpressed in the R0 group.

Conclusions: Taken together, our preliminary data suggest that molecular characteristics of EVs could provide an accurate prediction of patients with HGSC who can undergo CGR with surgery and respond to chemotherapy.

Citation Format: Li Zhao, Shaolin Ma, Nicole D. Fleming, Joseph Celestino, Mark S. Kim, Richard A. Hajek, Nicholas B. Jennings, Erika J. Thompson, Hongli Tang, Shannon N. Westin, Amir A. Jazaeri, Jianhua Zhang, P Andrew Futreal, Anil K. Sood, Sanghoon Lee. Distinct molecular profiles of serum-derived extracellular vesicles in high-grade serous ovarian cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5106.

Abstract 5738: Transcriptomic profiles of response to neoadjuvant chemotherapy in patients with high-grade serous ovarian cancer

Background: High-grade serous ovarian cancer (HGSC) is the most aggressive epithelial ovarian cancer, exhibiting tumor heterogeneity, molecular abnormality, and variable clinical outcomes. The heterogeneity and apparent adaptability of the HGSC genome under selective pressure by chemotherapy likely explain the high rates of drug resistance in HGSC. However, the underlying mechanisms of drug resistance are not well understood. Following our previous findings of significant distinct molecular and cellular characteristics in pre-treatment tumor samples from highly clinically annotated HGSC patients who received neoadjuvant chemotherapy (NACT), we examined post-treatment transcriptomic changes associated with excellent or poor responders to NACT in HGSC patients.

Methods: Thirty tumor tissues (pre- and post-treatment) after 3 to 4 cycles of NACT were collected from HGSC patients at interval cytoreductive debulking surgery from the following groups: excellent response to NACT with carboplatin/paclitaxel (post-ER, n=8); poor response to NACT (post-PR, n=8). Primary or metastatic sites for each patient were obtained (n=13, post-ER; n=17, post-PR) and subjected to RNA sequencing. The downstream bioinformatics analysis was then performed and compared with the data from the matched pre-NACT samples from the same patients (Lee et al., Cell Reports, 2020).

Results: We identified a total of 9,764 upregulated and 2,762 downregulated differentially expressed genes (DEGs, absolute log2FC &gt;=2, adj-p&lt;0.05) in the post-NACT samples vs the pre-NACT samples in the ER group. In contrast, 11,246 upregulated and 1,320 downregulated DEGs were found in the NACT-PR group. Ovarian cancer-related genes, including KRAS, NRAS, BRCA1/2, RB1, NF1, MLH1, PIK3CA, MSH2, AKT1, and NOTCH3 were differentially expressed in post-NACT vs pre-NACT in both ER and PR groups. TP53 was exclusively upregulated in post-ER vs pre-ER, and GABRA6 was exclusively upregulated in post-PR vs pre-PR. In signaling pathway analysis, apoptosis and DNA repair-related pathways were exclusively downregulated in post-ER vs pre-ER. Interestingly, the percentage of immune cells − CD8 and macrophages M0 were significantly elevated in post-ER (p&lt;0.05), while γδ T cells and activated dendritic cells were significantly decreased in the post-ER (p&lt;0.05), not in the PR. Neutrophil cells were significantly lower in post-PR vs pre-PR, but not in ER group. We also found that the level of ESR1 decreased significantly in post-ER vs post-PR (p&lt;0.05). The level of PAX8 significantly increased in post-PR vs post-ER (p&lt;0.05).

Conclusions: Our transcriptomic analysis revealed distinct transcripts changes in post-NACT vs pre-NACT tumor tissues from HGSC patients with excellent or poor response to the NACT. These findings could enhance treatment decision-making and rationale for developing alternative therapies for patients with HGSC.

Citation Format: Sanghoon Lee, Li Zhao, Nicole D. Fleming, Joseph Celestino, Richard A. Hajek, Margaret B. Morgan, Yan Liu, Shannon N. Westin, Amir A. Jazaeri, Jinsong Liu, Jianhua Zhang, P Andrew Futreal, Anil K. Sood. Transcriptomic profiles of response to neoadjuvant chemotherapy in patients with high-grade serous ovarian cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5738.

Abstract 4135: Initial clinicopathologic and molecular characterization of minimal residual disease detected by second look laparoscopy after completion of frontline surgery and chemotherapy in patients with advanced stage ovarian cancer

Background: Despite high rates of remission after frontline management, most patients with advanced stage ovarian cancer recur. Second look laparoscopy (SLL) can provide more sensitive detection of minimal residual disease (MRD) allowing for more individualized prognostication and possible therapeutic intervention. It may also assess tumor biology and microenvironment associated with undetectable chemoresistant MRD phase of ovarian cancer. The objective of this study was to determine SLL feasibility, and clinicopathologic and molecular characteristics of MRD after frontline therapy in ovarian cancer.

Methods: SLL was offered to patients with stage III-IV high grade epithelial ovarian cancer who achieved complete response after frontline surgery and 6 cycles of carboplatin and paclitaxel chemotherapy. Patients were offered standard of care or investigational management options based on homologous recombination deficiency (HRD) and MRD status at SLL. Preliminary translational studies included RNAseq for comparison of serial, matched tumor from primary or interval TRS and SLL derived MRD+ biopsies at the time of SLL. In addition, Nanostring analyses of SLL surgical biopsies both with and without residual tumor were performed. Molecular profiling employed hierarchical clustering, principle component analysis, non-parametric testing, and pathway analyses.

Results: Between 4/2017- 7/2021, 39 patients underwent SLL. The majority had stage III disease (74%), high grade serous histology (90%) and underwent neoadjuvant chemotherapy with interval tumor reductive surgery (TRS; 54%). MRD was present in 49% (n=19) of patients and was more frequent among neoadjuvant chemotherapy recipients (73% vs 26%, P=0.015) and patients with homologous recombination proficient tumors (81% vs 25%, P=0.01). Most patients without MRD were dispositioned to observation; 4 patients with HRD received a PARP inhibitor per standard of care. All other patients with MRD received bevacizumab as part of a clinical trial, except for one patient who received a PARP inhibitor. Median follow-up was 6.74 months (range 0.66 - 28.62). Presence of MRD was associated with worse PFS (HR 3.7, 95% CI 1.3- 10.9; 5.5 vs 24.6 months; P= 0.02). Based on transcriptional signature, MRD are immunologically distinct from untreated tumors or those collected at interval TRS (after 3 cycles of chemo) but also displayed heterogeneity with two distinct subclusters.

Conclusions: SLL to assess for MRD has potential to further individualize post-frontline therapy, and identify patients at high risk for progression for early intervention clinical trials. Transcriptional profiling suggests that MRD phase of ovarian cancer is characterized by a distinct, heterogeneous, and evolving tumor and immune microenvironment.

Citation Format: Roni Nitecki, Minghao Dang, Sanghoon Lee, Bryan Fellman, J Alejandro Rauh-hain, Jolyn Taylor, Lois Ramondetta, Michaela Grinsfelder, Lauren Cobb, David M. Boruta, Pamela T. Soliman, Aaron Shafer, Nicole D. Fleming, Shannon N. Westin, Anil K. Sood, Chris Tanguma, Pedro T. Ramrez, Karen H. Lu, Linghua Wang, Amir A. Jazaeri. Initial clinicopathologic and molecular characterization of minimal residual disease detected by second look laparoscopy after completion of frontline surgery and chemotherapy in patients with advanced stage ovarian cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 4135.

Androgen receptor blockade promotes response to BRAF/MEK-targeted therapy

Treatment with therapy targeting BRAF and MEK (BRAF/MEK) has revolutionized care in melanoma and other cancers; however, therapeutic resistance is common and innovative treatment strategies are needed^1,2. Here we studied a group of patients with melanoma who were treated with neoadjuvant BRAF/MEK-targeted therapy ( NCT02231775 , n = 51) and observed significantly higher rates of major pathological response (MPR; ≤10% viable tumour at resection) and improved recurrence-free survival (RFS) in female versus male patients (MPR, 66% versus 14%, P = 0.001; RFS, 64% versus 32% at 2 years, P = 0.021). The findings were validated in several additional cohorts^2-4 of patients with unresectable metastatic melanoma who were treated with BRAF- and/or MEK-targeted therapy (n = 664 patients in total), demonstrating improved progression-free survival and overall survival in female versus male patients in several of these studies. Studies in preclinical models demonstrated significantly impaired anti-tumour activity in male versus female mice after BRAF/MEK-targeted therapy (P = 0.006), with significantly higher expression of the androgen receptor in tumours of male and female BRAF/MEK-treated mice versus the control (P = 0.0006 and P = 0.0025). Pharmacological inhibition of androgen receptor signalling improved responses to BRAF/MEK-targeted therapy in male and female mice (P = 0.018 and P = 0.003), whereas induction of androgen receptor signalling (through testosterone administration) was associated with a significantly impaired response to BRAF/MEK-targeted therapy in male and female patients (P = 0.021 and P < 0.0001). Together, these results have important implications for therapy.

Clinical analysis of pathologic complete responders in advanced-stage ovarian cancer

OBJECTIVE

To determine the clinical characteristics of patients who attained pathologic complete response (pCR) after neoadjuvant chemotherapy (NACT) and to identify specific predictive or prognostic factors associated with pCR.

METHODS

Two distinct populations of patients who underwent NACT followed by interval tumor reductive surgery (TRS) were used in this retrospective study. The first contained 472 patients from a single institution. The second contained only pCR patients (67); those identified from population one, plus 44 obtained through collaborative institutions. Cox analysis and log-rank tests were performed to assess associations between clinical characteristics and pCR outcome, recurrence-free survival (RFS), and overall survival (OS).

RESULTS

The median RFS and OS in our pCR-only population was 24.2 and 80.8 months, respectively, with a median follow-up time of 32.4 months. In our single institution population, 23 patients attained pCR (4.9%) and had longer RFS compared to non-pCR patients with viable microscopic, optimal, or suboptimal residual disease (24.3 vs. 12.1 vs. 11.6 vs. 9.6 months, p = 0.025, 0.012, 0.008, respectively), and longer OS compared to those with optimal or suboptimal residual disease (54.5 vs. 29.4 vs. 25.7 months, p = 0.027, 0.007, respectively). Patients were more than three-fold likely to attain pCR if their CA125 value was normal at the time of surgery (OR 3.54, 95% CI: 1.14-11.05, p = 0.029).

CONCLUSIONS

Women with pCR after NACT have significantly longer RFS compared to those with residual viable tumor at the time of interval tumor-reductive surgery, and CA125 is plausible biomarker for identifying these extreme responders preoperatively.

Phase Ib Dose Expansion and Translational Analyses of Olaparib in Combination with Capivasertib in Recurrent Endometrial, Triple-Negative Breast, and Ovarian Cancer

PURPOSE

On the basis of strong preclinical rationale, we sought to confirm recommended phase II dose (RP2D) for olaparib, a PARP inhibitor, combined with the AKT inhibitor capivasertib and assess molecular markers of response and resistance.

PATIENTS AND METHODS

We performed a safety lead-in followed by expansion in endometrial, triple-negative breast, ovarian, fallopian tube, or peritoneal cancer. Olaparib 300 mg orally twice daily and capivasertib orally twice daily on a 4-day on 3-day off schedule was evaluated. Two dose levels (DL) of capivasertib were planned: 400 mg (DL1) and 320 mg (DL-1). Patients underwent biopsies at baseline and 28 days.

RESULTS

A total of 38 patients were enrolled. Seven (18%) had germline BRCA1/2 mutations. The first 2 patients on DL1 experienced dose-limiting toxicities (DLT) of diarrhea and vomiting. No DLTs were observed on DL-1 (n = 6); therefore, DL1 was reexplored (n = 6) with no DLTs, confirming DL1 as RP2D. Most common treatment-related grade 3/4 adverse events were anemia (23.7%) and leukopenia (10.5%). Of 32 evaluable subjects, 6 (19%) had partial response (PR); PR rate was 44.4% in endometrial cancer. Seven (22%) additional patients had stable disease greater than 4 months. Tumor analysis demonstrated strong correlations between response and immune activity, cell-cycle alterations, and DNA damage response. Therapy resistance was associated with receptor tyrosine kinase and RAS-MAPK pathway activity, metabolism, and epigenetics.

CONCLUSIONS

The combination of olaparib and capivasertib is associated to no serious adverse events and demonstrates durable activity in ovarian, endometrial, and breast cancers, with promising responses in endometrial cancer. Importantly, tumor samples acquired pre- and on-therapy can help predict patient benefit.

ATHENA (GOG-3020/ENGOT-ov45): a randomized, phase III trial to evaluate rucaparib as monotherapy (ATHENA-MONO) and rucaparib in combination with nivolumab (ATHENA-COMBO) as maintenance treatment following frontline platinum-based chemotherapy in ovarian cancer

Background

The optimal treatment strategy for women with newly diagnosed ovarian cancer has yet to be determined. Poly(ADP-ribose) polymerase (PARP) inhibitors have demonstrated substantial improvement in progression-free survival as monotherapy maintenance treatment in the frontline setting versus active surveillance. Furthermore, preclinical and early clinical studies have shown that PARP inhibitors and immune checkpoint inhibitors have synergistic antitumor activity and may provide an additional therapeutic option for patients in this population.

Primary Objectives

In women with newly diagnosed ovarian, fallopian tube, or peritoneal cancer, we wish to assess the efficacy of frontline maintenance treatment with the PARP inhibitor rucaparib versus placebo following response to platinum-based chemotherapy (ATHENA–MONO), and to assess the combination of rucaparib plus nivolumab (a programmed death receptor 1 (PD-1)–blocking monoclonal antibody) versus rucaparib alone (ATHENA–COMBO).

Study Hypothesis

(1) Maintenance therapy with rucaparib monotherapy may extend progression-free survival following standard treatment for ovarian cancer in the frontline setting. (2) The combination of nivolumab plus rucaparib may extend progression-free survival following standard treatment for ovarian cancer in the frontline setting compared with rucaparib alone.

Trial Design

ATHENA is an international, randomized, double-blind, phase III trial consisting of two independent comparisons (ATHENA–MONO and ATHENA–COMBO) in patients with newly diagnosed platinum-sensitive ovarian cancer. Patients are randomized 4:4:1:1 to the following: oral rucaparib+ intravenous nivolumab (arm A); oral rucaparib + intravenous placebo (arm B); oral placebo+ intravenous nivolumab (arm C); and oral placebo + intravenous placebo (arm D). The starting dose of rucaparib is 600 mg orally twice a day and nivolumab 480 mg intravenously every 4 weeks. ATHENA–MONO compares arm B with arm D to evaluate rucaparib monotherapy versus placebo, and ATHENA–COMBO evaluates arm A versus arm B to investigate the effects of rucaparib and nivolumab in combination versus rucaparib monotherapy. ATHENA–MONO and ATHENA–COMBO share a common treatment arm (arm B) but each comparison is independently powered.

Major Inclusion/Exclusion Criteria

Patients ≥18 years of age with newly diagnosed advanced, high-grade epithelial ovarian, primary peritoneal, or fallopian tube cancer who have achieved a response after completion of cytoreductive surgery and initial platinum-based chemotherapy are enrolled. No other prior treatment for ovarian cancer, other than the frontline platinum regimen, is permitted.

Primary Endpoint

The primary endpoint is investigator-assessed progression-free survival by Response Evaluation Criteria in Solid Tumors v1.1.

Sample Size

Approximately 1000 patients have been enrolled and randomized.

Estimated Dates for Completing Accrual and Presenting Results

The trial completed accrual in 2020. While dependent on event rates, primary results of ATHENA–MONO are anticipated in early 2022 and results of ATHENA–COMBO are anticipated to mature at a later date.

Trial Registration

This trial is registered at clinicaltrials.gov (NCT03522246).

Rational Combination of CRM1 Inhibitor Selinexor and Olaparib Shows Synergy in Ovarian Cancer Cell Lines and Mouse Models

CRM1 inhibitors have demonstrated antitumor effects in ovarian and other cancers; however, rational combinations are largely unexplored. We performed a high-throughput drug library screen to identify drugs that might combine well with selinexor in ovarian cancer. Next, we tested the combination of selinexor with the top hit from the drug screen in vitro and in vivo Finally, we assessed for mechanisms underlying the identified synergy using reverse phase protein arrays (RPPA). The drug library screen assessing 688 drugs identified olaparib (a PARP inhibitor) as the most synergistic combination with selinexor. Synergy was further demonstrated by MTT assays. In the A2780luc ip1 mouse model, the combination of selinexor and olaparib yielded significantly lower tumor weight and fewer tumor nodules compared with the control group (P < 0.04 and P < 0.03). In the OVCAR5 mouse model, the combination yielded significantly fewer nodules (P = 0.006) and markedly lower tumor weight compared with the control group (P = 0.059). RPPA analysis indicated decreased expression of DNA damage repair proteins and increased expression of tumor suppressor proteins in the combination treatment group. Collectively, our preclinical findings indicate that combination with selinexor to expand the utility and efficacy of PARP inhibitors in ovarian cancer warrants further exploration.

Immune microenvironment composition in high-grade serous ovarian cancers based on BRCA mutational status

PURPOSE

An in-depth analysis of the tumor microenvironment of ovarian cancer is needed. The purpose of this study was to elucidate the architecture of the immune microenvironment of high-grade serous ovarian cancers (HGSCs) with or without BRCA1 and BRCA2 mutations.

METHODS

A cohort of highly annotated HGSC patients with known germline BRCA1 and BRCA2 status was selected, and pretreatment tumor tissue specimens were analyzed with a multiplexed staining technique aimed at detecting lymphocytes, macrophages, and fibroblasts in the whole tumor area and in specific regions including epithelium, stroma, and perivascular areas.

RESULTS

BRCA1- or BRCA2-mutated tumors showed a more immunogenic microenvironment, characterized by a higher abundance of CD8⁺ and PD-L1⁺ cells, than did tumors with wild-type BRCA1 and BRCA2. High numbers of PD-L1⁺ and PD-L1⁺CD8⁺ cells were prognostic for event-free survival (hazard ratio [HR]: 0.41, 95% CI 0.21-0.79, p = 0.008 and HR 0.49, 95% CI 0.26-0.91, p = 0.025, respectively), as were high numbers of epithelial PD-L1⁺ and FAP⁺PD-L1⁺ cells (HR 0.52, 95% CI 0.28-0.96, p = 0.037 and HR 0.27, 95% CI 0.08-0.87, p = 0.029) and CD8⁺ cells (HR 0.51, 95% CI 0.28-0.93, p = 0.027).

CONCLUSIONS

This study reveals substantial differences between the immune microenvironment composition of germline BRCA-mutated and BRCA wild-type HGSC.

Risk factors for progression or death after first-line platinum-based chemotherapy in real-world patients in the USA with ovarian cancer from 2011 to 2018

Aim: Patient chart data from the USA during the period of January 2011 through October 2018 were used to assess risk factors for progression in advanced ovarian cancer after response to first-line platinum-based chemotherapy. Patients & methods: Patients with stage III/IV ovarian cancer who completed first-line platinum-based chemotherapy after primary or interval debulking surgery were identified from the Flatiron Health database. Cox proportional hazards modeling was used to assess associations between baseline factors and time to next treatment (TTNT) or overall survival (OS). Results: Patients at stage IV or who received interval debulking surgery had shorter TTNT and OS than patients at stage III or who received primary debulking surgery, respectively. OS was worse in patients with residual disease and in BRCA wild-type. Conclusion: Multiple factors were associated with shorter TTNT or OS in this retrospective real-world analysis.

Movement of Poly-ADP Ribose (PARP) Inhibition into Frontline Treatment of Ovarian Cancer

The use of poly (ADP-ribose) polymerase (PARP) inhibitors in the front-line management of advanced ovarian cancer has recently emerged as an exciting strategy with the potential to improve outcomes for patients with advanced ovarian cancer. In this article, we review the results of four recently published Phase III randomised controlled trials evaluating the use of PARP inhibitors in the primary treatment of ovarian cancer (SOLO1, PRIMA, PAOLA-1, and VELIA). Collectively, the studies suggest that PARP maintenance in the upfront setting is most beneficial among patients with BRCA-associated ovarian cancers (hazard ratios range from 0.31 to 0.44), followed by patients with tumours that harbour homologous recombination deficiencies (hazard ratios range from 0.33 to 0.57). All three studies that included an all-comer population were able to demonstrate benefit of PARP inhibitors, regardless of biomarker status. The FDA has approved olaparib for front-line maintenance therapy among patients with BRCA-associated ovarian cancers, and niraparib for all patients, regardless of biomarker status. In determining which patients should be offered front-line maintenance PARP inhibitors, and which agent to use, there are multiple factors to consider, including FDA indication, dosing preference, toxicity, risks versus benefits for each patient population, and cost. There are ongoing studies further exploring the front-line use of PARP inhibitors, including the potential downstream effects of PARP-inhibitor resistance in the recurrent setting, combining PARP-inhibitors with other anti-angiogenic drugs, immunotherapeutic agents, and inhibitors of pathways implicated in PARP inhibitor resistance.

Factors associated with response to neoadjuvant chemotherapy in advanced stage ovarian cancer

OBJECTIVES

To evaluate the factors associated with response to neoadjuvant chemotherapy (NACT) and the ability to undergo interval tumor reductive surgery (iTRS) in patients with advanced ovarian cancer.

METHODS

We performed a retrospective review from April 2013 to March 2019 of patients with advanced stage ovarian cancer triaged to NACT based on our standard triage algorithm. Clinicopathologic and treatment data were analyzed for factors associated with response to NACT, outcomes at iTRS, and their impact on progression-free survival (PFS).

RESULTS

562 patients met inclusion criteria and triaged to NACT following laparoscopy (n = 132) or without laparoscopy (n = 430). 413 patients underwent iTRS (74%). Factors that correlated with a patient reaching iTRS included increasing age (p < 0.001), higher Charlson comorbidity index (p < 0.001), ECOG status 2 or 3 (<0.001), and laparoscopic assessment (<0.001). Patients with CA-125 ≤ 35 U/mL at iTRS had higher rates of complete gross resection (88% vs. 65%, p < 0.001) and improved PFS (16.8 vs. 12.7 months, p < 0.001). Patients receiving dose-dense paclitaxel (76% vs. 60%, p = 0.004) and CA-125 ≤ 35 U/mL at iTRS (85% vs. 66%, p < 0.001) had higher rates of complete radiographic response. On multivariate analysis, germline BRCA 1/2 mutation (p = 0.001), iTRS vs. no surgery (R0, p < 0.001; ≤1 cm, p < 0.001; >1 cm, p < 0.001), dose-dense chemotherapy (p = 0.01), and CA-125 ≤ 35 U/mL at iTRS (p = 0.001) were independent significant factors affecting PFS.

CONCLUSIONS

Normalization of CA-125 at the time of iTRS following NACT may serve as a surrogate marker for prognosis in this high-risk population. Our NACT cohort experienced improved response rates and PFS with dose-dense therapy compared to conventional dosing.

Rationale for combination PARP inhibitor and antiangiogenic treatment in advanced epithelial ovarian cancer: A review

Inhibitors of poly(ADP-ribose) polymerase (PARP) and angiogenesis have demonstrated single-agent activity in women with advanced ovarian cancer. Recent studies have aimed to establish whether combination therapy can augment the response seen with PARP inhibitors or antiangiogenic agents alone. This review provides an overview of PARP inhibitors and antiangiogenics as monotherapy in women with advanced ovarian cancer, explores potential mechanisms of action of PARP inhibitor and antiangiogenic combination treatments, reviews efficacy and safety data from trials evaluating this combination, and outlines ongoing and future trials evaluating this combination, discussing these in the context of the current and future treatment landscape for women with advanced ovarian cancer. Sentinel studies evaluating PARP inhibitor (n = 8), antiangiogenic (n = 4), and combination (n = 7) therapy were identified in women with newly diagnosed (n = 7) and recurrent (n = 12) ovarian cancer. PARP inhibitors included olaparib (n = 9), niraparib (n = 4), rucaparib (n = 1), and veliparib (n = 1). Antiangiogenic agents included bevacizumab (n = 7) and cediranib (n = 4). PARP inhibitors combined with antiangiogenics demonstrated efficacy based on objective response rates and progression-free survival (PFS) in the relapsed disease setting. Maintenance therapy with the PARP inhibitor, olaparib, plus antiangiogenic therapy offered a significant PFS benefit versus the antiangiogenic alone in women with newly diagnosed advanced ovarian cancer who tested positive for homologous recombination deficiency. Combination therapy was tolerated, with no new safety signals reported compared with monotherapy trials. PARP inhibitors and antiangiogenics have changed the landscape of ovarian cancer treatment. The PARP inhibitor plus antiangiogenic combination is a novel treatment option that appears promising in the first-line advanced and recurrent ovarian cancer settings, although the role of this combination in recurrent disease requires further elucidation. Defining which patients are candidates for monotherapy or combination therapy is critical, taking into consideration safety profiles of therapies alone or in combination, and how these treatments should be sequenced in clinical practice.