A phase 2 study of dasatinib in recurrent clear cell carcinoma of the ovary, fallopian tube, peritoneum or endometrium: NRG oncology/gynecologic oncology group study 0283.

OBJECTIVE: Gynecologic cancers are traditionally managed according to their presumed site of origin, without regard to the underlying histologic subtype. Clear cell histology is associated with chemotherapy refractoriness and poor survival. Mutations in SWI/SNF chromatin remodeling complex member ARID1A, which encodes for BAF250a protein, are common in clear cell and endometriosis-associated endometrioid carcinomas. High-throughput cell-based drug screening predicted activity of dasatinib, a tyrosine kinase inhibitor, in ARID1A-mutant clear cell carcinoma. METHODS: We conducted a phase 2 clinical trial of dasatinib 140 mg once daily by mouth in patients with recurrent or persistent ovarian and endometrial clear cell carcinoma. Patients with measurable disease were enrolled and then assigned to biomarker-defined populations based on BAF250a immunohistochemistry. The translational endpoints included broad next-generation sequencing to assess concordance of protein expression and treatment outcomes. RESULTS: Twenty-eight patients, 15 of whom had tumors with retained BAF250a and 13 with loss of BAF250a were evaluable for treatment response and safety. The most common grade 3 adverse events were anemia, fatigue, dyspnea, hyponatremia, pleural effusion, and vomiting. One patient had a partial response, eight (28%) had stable disease, and 15 (53.6%) had disease progression. Twenty-three patients had next-generation sequencing results; 13 had a pathogenic ARID1A alteration. PIK3CA mutations were more prevalent in ARID1A-mutant tumors, while TP53 mutations were more prevalent in ARID1A wild-type tumors. CONCLUSIONS: Dasatinib was not an effective single-agent treatment for recurrent or persistent ovarian and endometrial clear cell carcinoma. Studies are urgently needed for this rare gynecologic subtype.

Pre-operative neoadjuvant chemotherapy cycles and survival in newly diagnosed ovarian cancer: what is the optimal number? A Memorial Sloan Kettering Cancer Center Team Ovary study.

OBJECTIVE: Although trials of neoadjuvant chemotherapy in ovarian cancer use 3 neoadjuvant cycles, real-world practice varies. We sought to evaluate the influence of increasing pre-operative cycles on survival, accounting for surgical outcomes. METHODS: We identified 199 women with newly diagnosed ovarian cancer recommended for neoadjuvant chemotherapy who underwent interval debulking surgery from July 2015 to December 2018. Non-parametric tests were used to compare clinical characteristics by neoadjuvant cycles. The Kaplan-Meier method was used to estimate differences in progression-free and overall survival. The log-rank test was used to assess the relationship of covariates to outcome. RESULTS: The median number of neoadjuvant cycles was 4 (range 3-8), with 56 (28%) women receiving ≥5 cycles. Compared with those receiving 3 or 4, women with ≥5 neoadjuvant cycles received fewer or no post-operative cycles (p<0.001) but had no other differences in clinical factors (p>0.05). Complete gross resection rates were similar among those receiving 3, 4, and ≥5 neoadjuvant cycles (68.5%, 70%, and 71.4%, respectively, p=0.96). There were no significant differences in progression-free or overall survival when comparing 3 versus 4 neoadjuvant cycles. However, more cycles (≥5 vs 4) were associated with worse progression-free survival, even after adjustment for BRCA status and complete gross resection (HR 2.20, 95% CI 1.45 to 3.33, p<0.001), and worse overall survival, even after adjustment for histology, response on imaging, and complete gross resection rates (HR 2.78, 95% CI 1.37 to 5.63, p=0.016). The most common reason for receiving ≥5 cycles was extent of disease requiring more neoadjuvant chemotherapy. CONCLUSIONS: Despite maximal cytoreduction, patients receiving ≥5 neoadjuvant cycles have a poorer prognosis than those receiving 3-4 cycles. Future studies should focus on reducing surgical morbidity and optimizing novel therapies in this high-risk group.

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.

Activity of M3814, an Oral DNA-PK Inhibitor, In Combination with Topoisomerase II Inhibitors in Ovarian Cancer Models.

DNA-dependent protein kinase (DNA-PK) has been shown to play a crucial role in repair of DNA double-strand breaks, facilitating nonhomologous end-joining. DNA-PK inhibitors have the potential to block DNA repair and therefore enhance DNA-damaging agents. M3814 is a DNA-PK inhibitor that has shown preclinical activity in combination with DNA-damaging agents, including radiotherapy and topoisomerase II inhibitors. Here we evaluated the activity of M3814 in combination with multiple topoisomerase II inhibitors, doxorubicin, etoposide, and pegylated liposomal doxorubicin (PLD) in vivo, utilizing ovarian cancer xenografts. Using cell lines representative of P53 wild-type ovarian cancer (A2780), and P53 mutant ovarian cancer (SKOV3), cells were implanted in the flank of athymic nude female mice. Mice were treated with vehicle, M3814 alone, topoisomerase II inhibitor alone, and M3814 in combination with topoisomerase II inhibitor, and change in tumor volume over time was documented. The addition of M3814 was well tolerated. We demonstrated that M3814 shows limited efficacy as a single agent in ovarian cancer models. The combination of M3814 with PLD showed enhanced activity over PLD as a single agent. Further study of this combination is warranted.

Integrative Development of a TLR8 Agonist for Ovarian Cancer Chemoimmunotherapy.

Purpose: Immunotherapy is an emerging paradigm for the treatment of cancer, but the potential efficacy of many drugs cannot be sufficiently tested in the mouse. We sought to develop a rational combination of motolimod-a novel Toll-like receptor 8 (TLR8) agonist that stimulates robust innate immune responses in humans but diminished responses in mice-with pegylated liposomal doxorubicin (PLD), a chemotherapeutic that induces immunogenic cell death.Experimental Design: We followed an integrative pharmacologic approach including healthy human volunteers, non-human primates, NSG-HIS ("humanized immune system") mice reconstituted with human CD34+ cells, and patients with cancer to test the effects of motolimod and to assess the combination of motolimod with PLD for the treatment of ovarian cancer.Results: The pharmacodynamic effects of motolimod monotherapy in NSG-HIS mice closely mimicked those in non-human primates and healthy human subjects, whereas the effects of the motolimod/PLD combination in tumor-bearing NSG-HIS mice closely mimicked those in patients with ovarian cancer treated in a phase Ib trial (NCT01294293). The NSG-HIS mouse helped elucidate the mechanism of action of the combination and revealed a positive interaction between the two drugs in vivo The combination produced no dose-limiting toxicities in patients with ovarian cancer. Two subjects (15%) had complete responses and 7 subjects (53%) had disease stabilization. A phase II study was consequently initiated.Conclusions: These results are the first to demonstrate the value of pharmacologic approaches integrating the NSG-HIS mouse, non-human primates, and patients with cancer for the development of novel immunomodulatory anticancer agents with human specificity. Clin Cancer Res; 23(8); 1955-66. ©2016 AACR.

Role of pegylated liposomal doxorubicin in ovarian cancer.

OBJECTIVES: Safe, effective treatments are needed for relapsed ovarian cancer. Goals include improving symptoms, enhancing quality of life, and prolonging survival. The plethora of agents currently available present difficult choices for physicians. The present effort seeks to examine the role of one of these agents, pegylated liposomal doxorubicin. METHODS: A roundtable meeting of experts in the management of ovarian carcinoma was held to build consensus around the present and future role of pegylated liposomal doxorubicin for ovarian cancer and other gynecologic malignancies. RESULTS: Pegylated liposomal doxorubicin is effective and well tolerated in relapsed ovarian cancer. When compared with topotecan in a phase III randomized trial, pegylated liposomal doxorubicin showed several advantages: improved quality of life, fewer severe adverse events, fewer dose modifications, less hematologic support, and lower total cost per patient. In platinum-sensitive patients, pegylated liposomal doxorubicin also produced a survival advantage. Results from prospective and retrospective studies further demonstrate the improved cardiac safety of pegylated liposomal doxorubicin compared to conventional anthracyclines. CONCLUSIONS: Based on survival and toxicity advantages and a once-monthly administration schedule, pegylated liposomal doxorubicin is the first-choice nonplatinum agent for relapsed ovarian cancer. Pegylated liposomal doxorubicin may also have clinical application in combination regimens for platinum-sensitive ovarian cancer, as consolidation/maintenance therapy for ovarian cancer, as a component of first-line therapy for ovarian cancer, and in the treatment of other gynecologic malignancies. Future clinical trials will further define and maximize the role of pegylated liposomal doxorubicin in the treatment of ovarian cancer and other gynecologic malignancies.