A phase II trial of trebananib (AMG 386; IND#111071), a selective angiopoietin 1/2 neutralizing peptibody, in patients with persistent/recurrent carcinoma of the endometrium: An NRG/Gynecologic Oncology Group trial

Locally advanced and metastatic endometrial cancer: Current and emerging therapies

Until recently, patients diagnosed with locally advanced and metastatic endometrial cancer faced significant challenges in their treatment due to limited options and poor prognostic outcomes. The sequencing of tumors has been a major advancement in its management. It has led to The Cancer Genome Atlas classification currently used in clinical practice and the initiation of several clinical trials for innovative treatments targeting principally signaling pathways, immune checkpoints, DNA integrity, growth factors, hormonal signaling, and metabolism. Numerous clinical trials are investigating a combinatorial approach of these targeted therapies to counter tumoral resistance, cellular compensatory mechanisms, and tumor polyclonality. This review provides a comprehensive overview of historical, current, and promising therapies in advanced and metastatic endometrial cancer. It particularly highlights clinical research on targeted and hormonal therapies, but also immunotherapy, reflecting the evolving landscape of treatment modalities for this disease.

Antiangiogenic properties of BthMP, a P-I metalloproteinase from Bothrops moojeni snake venom by VEGF pathway in endothelial cells

Angiogenesis is a process that is controlled by a delicate combination of proangiogenic and antiangiogenic molecules and can be disrupted in various illnesses, including cancer. Non-cancerous diseases can also have an abnormal or insufficient vascular growth, inflammation and hypoxia, which exacerbate angiogenesis. These conditions include atherosclerosis, psoriasis, endometriosis, asthma, obesity and AIDS. Based on that, the present work assessed the in vitro and ex vivo antiangiogenic properties stemming from BthMP, a P-I metalloproteinase from Bothrops moojeni snake venom, via the VEGF pathway. BthMP at a concentration of 5 and 40 μg/mL showed no toxicity to endothelial cells (HUVEC) in the MTT assay and was not able to induce necrosis and colony proliferation. Interestingly, BthMP inhibited adhesion, migration and invasion of HUVECs in Matrigel and arrested in vitro angiogenesis by reducing the average number of nodules in toxin-treated cells by 9.6 and 17.32 at 5 and 40 μg/mL, respectively, and the number of tubules by 15.9 at 5 μg/mL and 21.6 at 40 μg/mL in a VEGF-dependent way, an essential proangiogenic property. Furthermore, BthMP inhibited the occurrence of the angiogenic process in an ex vivo aortic ring test by decreasing new vessel formation by 52% at 5 μg/mL and by 66% at 40 μg/mL and by increasing the expression of an antiangiogenic gene, SFLT-1, and decreasing the expression of the proangiogenic genes VEGFA and ANGPT-1. Finally, this toxin reduces the production of nitric oxide, a marker that promotes angiogenesis and VEGF modulation, and decreases the protein expression of VEGFA in the supernatant of the HUVEC culture by about 30 %. These results suggest that BthMP has a promising antiangiogenic property and proves to be a biotechnological mechanism for understanding the antiangiogenic responses induced by snake venom metalloproteinases, which could be applied to a variety of diseases that exhibit an imbalance of angiogenesis mechanisms.

New insights for gynecological cancer therapies: from molecular mechanisms and clinical evidence to future directions

Advanced and recurrent gynecological cancers lack effective treatment and have poor prognosis. Besides, there is urgent need for conservative treatment for fertility protection of young patients. Therefore, continued efforts are needed to further define underlying therapeutic targets and explore novel targeted strategies. Considerable advancements have been made with new insights into molecular mechanisms on cancer progression and breakthroughs in novel treatment strategies. Herein, we review the research that holds unique novelty and potential translational power to alter the current landscape of gynecological cancers and improve effective treatments. We outline the advent of promising therapies with their targeted biomolecules, including hormone receptor-targeted agents, inhibitors targeting epigenetic regulators, antiangiogenic agents, inhibitors of abnormal signaling pathways, poly (ADP-ribose) polymerase (PARP) inhibitors, agents targeting immune-suppressive regulators, and repurposed existing drugs. We particularly highlight clinical evidence and trace the ongoing clinical trials to investigate the translational value. Taken together, we conduct a thorough review on emerging agents for gynecological cancer treatment and further discuss their potential challenges and future opportunities.

Bayesian optimal phase II designs with dual-criterion decision making

The conventional phase II trial design paradigm is to make the go/no-go decision based on the hypothesis testing framework. Statistical significance itself alone, however, may not be sufficient to establish that the drug is clinically effective enough to warrant confirmatory phase III trials. We propose the Bayesian optimal phase II trial design with dual-criterion decision making (BOP2-DC), which incorporates both statistical significance and clinical relevance into decision making. Based on the posterior probability that the treatment effect reaches the lower reference value (statistical significance) and the clinically meaningful value (clinical significance), BOP2-DC allows for go/consider/no-go decisions, rather than a binary go/no-go decision. BOP2-DC is highly flexible and accommodates various types of endpoints, including binary, continuous, time-to-event, multiple, and coprimary endpoints, in single-arm and randomized trials. The decision rule of BOP2-DC is optimized to maximize the probability of a go decision when the treatment is effective or minimize the expected sample size when the treatment is futile. Simulation studies show that the BOP2-DC design yields desirable operating characteristics. The software to implement BOP2-DC is freely available at www.trialdesign.org.

Diagnostic and Therapeutic Values of Angiogenic Factors in Endometrial Cancer

Endometrial cancer (EC) is the most frequent gynecological malignancy in developed countries and requires a relatively invasive diagnostic evaluation and operative therapy as the primary therapeutic approach. Angiogenesis is one of the main processes needed for cancer growth and spread. The production of angiogenic factors (AFs) appears early in the process of carcinogenesis. The detection of AFs in plasma and tissue and a better understanding of the angiogenic properties of EC may contribute not only to earlier but also more specific diagnosis and consequently tailored and individual therapeutic approaches. AFs and their receptors also have high potential as binding sites for targeted cancer therapy. In this review, we discuss angiogenesis in EC and the characteristics of the AFs that most contribute to angiogenesis in EC. We also highlight therapeutic strategies that target angiogenesis as potential EC therapy.

Recurrent Endometrial Cancer: Local and Systemic Treatment Options

The treatment of recurrent endometrial cancer is a challenge. Because of earlier treatments and the site of locoregional recurrence, in the vaginal vault or pelvis, morbidity can be high. A total of about 4 to 20% of the patients with endometrial cancer develop a locoregional recurrence, mostly among patients with locally advanced disease. The treatment options are dependent on previous treatments and the site of recurrence. Local and locoregional recurrences can be treated curatively with surgery or (chemo)radiotherapy with acceptable toxicity and control rates. Distant recurrences can be treated with palliative systemic therapy, i.e., first-line chemotherapy or hormonal therapy. Based on the tumor characteristics and molecular profile, there can be a role for immunotherapy. The evidence on targeted therapy is limited, with no approved treatment in the current guidelines. In selected cases, there might be an indication for local treatment in oligometastatic disease. Because of the novel techniques in radiotherapy, disease control can often be achieved at limited toxicity. Further studies are warranted to analyze the survival outcome and toxicity of newer treatment strategies. Patient selection is very important in deciding which treatment is of most benefit, and better prediction models based on the patient- and tumor characteristics are necessary.

Pharmacological Treatment of Advanced, Persistent or Metastatic Endometrial Cancer: State of the Art and Perspectives of Clinical Research for the Special Issue "Diagnosis and Management of Endometrial Cancer"

Patients with metastatic or recurrent endometrial cancer (EC) not suitable for surgery and/or radiotherapy are candidates for pharmacological treatment frequently with unsatisfactory clinical outcomes. The purpose of this paper was to review the results obtained with chemotherapy, hormonal therapy, biological agents and immune checkpoint inhibitors in this clinical setting. The combination of carboplatin (CBDCA) + paclitaxel (PTX) is the standard first-line chemotherapy capable of achieving objective response rates (ORRs) of 43-62%, a median progression-free survival (PFS) of 5.3-15 months and a median overall survival (OS) of 13.2-37.0 months, respectively, whereas hormonal therapy is sometimes used in selected patients with slow-growing steroid receptor-positive EC. The combination of endocrine therapy with m-TOR inhibitors or cyclin-dependent kinase 4/6 inhibitors is currently under evaluation. Disappointing ORRs have been associated with epidermal growth factor receptor (EGFR) inhibitors, HER-2 inhibitors and multi-tyrosine kinase inhibitors used as single agents, and clinical trials evaluating the addition of bevacizumab to CBDCA + PTX have reported conflicting results. Immune checkpoint inhibitors, and especially pembrolizumab and dostarlimab, have achieved an objective response in 27-47% of highly pretreated patients with microsatellite instability-high (MSI-H)/mismatch repair (MMR)-deficient (-d) EC. In a recent study, the combination of lenvatinib + pembrolizumab produced a 24-week response rate of 38% in patients with highly pretreated EC, ranging from 64% in patients with MSI-H/MMR-d to 36% in those with microsatellite stable/MMR-proficient tumors. Four trials are currently investigating the addition of immune checkpoint inhibitors to PTX + CBDCA in primary advanced or recurrent EC, and two trials are comparing pembrolizumab + lenvatinib versus either CBDCA + PTX as a first-line treatment of advanced or recurrent EC or versus single-agent chemotherapy in advanced, recurrent or metastatic EC after one prior platinum-based chemotherapy.

Angiopoietin inhibitors: A review on targeting tumor angiogenesis

Angiogenesis is the process of formation of new blood vessels from existing ones. Vessels serve the purpose of providing oxygen, nutrients and removal of waste from the cells. The physiological angiogenesis is a normal process and is required in the embryonic development, wound healing, menstrual cycle. For homeostasis, balance of pro angiogenic factors and anti angiogenic factors like is important. Their imbalance causes a process known as "angiogenic switch" which leads to various pathological conditions like inflammation, tumor and restenosis. Like normal cells, tumor cells also require oxygen and nutrients to grow which is provided by tumor angiogenesis. Hence angiogenic process can be inhibited to prevent tumor growth. This gives rise to study of anti angiogenic drugs. Currently approved anti angiogenic drugs are mostly VEGF inhibitors, but VEGF inhibitors have certain limitations like toxicity, low progression free survival (PFS), and resistance to anti VEGF therapy. This article focuses on angiopoietins as alternative and potential targets for anti angiogenic therapy. Angiopoietins are ligands of Tie receptor and play a crucial role in angiogenesis, their inhibition can prevent many tumor growths even on later stages of development. We present current clinical and preclinical stages of angiopoietin inhibitors. Drugs studied in the article are selective as well as non-selective inhibitors of angiopoietin 2 like Trebananib (AMG 386), AMG 780, REGN 910, CVX 060, MEDI 3617 and dual inhibitors of angiopoietin 2 and VEGF like Vanucizumab and RG7716. The angiopoietin inhibitors show promising results alone and in combination with VEGF inhibitors in various malignancies.

Angiogenesis in endometrial carcinoma: Therapies and biomarkers, current options, and future perspectives

Endometrial carcinoma is the most common gynecologic malignancy and the fourth most prevalent cancer in women in the modern world. Despite a relatively high chance of surgical cure, for patients with advanced or recurrent disease there are few therapeutic options. Angiogenesis has been extensively studied ever since vascular endothelial growth factor (VEGF) was discovered in the 1980s. Several clinical trials of anti-angiogenic therapy in endometrial carcinoma have been conducted, with mixed results, and many researchers have tried to determine prognostic and therapeutic biomarkers. Recent trials, which shed new light on possible treatment biomarkers and efficacious combination therapies, are reviewed in this text. While we are still far from effectively tailoring anti-angiogenic treatment to each patient, these data have provided valuable insight and have put us on track for the discovery of novel opportunities for angiogenesis therapy in endometrial carcinoma.

Angiogenesis in gynecological cancers and the options for anti-angiogenesis therapy

Angiogenesis is required in cancer, including gynecological cancers, for the growth of primary tumors and secondary metastases. Development of anti-angiogenesis therapy in gynecological cancers and improvement of its efficacy have been a major focus of fundamental and clinical research. However, survival benefits of current anti-angiogenic agents, such as bevacizumab, in patients with gynecological cancer, are modest. Therefore, a better understanding of angiogenesis and the tumor microenvironment in gynecological cancers is urgently needed to develop more effective anti-angiogenic therapies, either or not in combination with other therapeutic approaches. We describe the molecular aspects of (tumor) blood vessel formation and the tumor microenvironment and provide an extensive clinical overview of current anti-angiogenic therapies for gynecological cancers. We discuss the different phenotypes of angiogenic endothelial cells as potential therapeutic targets, strategies aimed at intervention in their metabolism, and approaches targeting their (inflammatory) tumor microenvironment.

Targeted therapies in gynecological cancers: a comprehensive review of clinical evidence

Advanced and recurrent gynecological cancers are associated with poor prognosis and lack of effective treatment. The developments of the molecular mechanisms on cancer progression provide insight into novel targeted therapies, which are emerging as groundbreaking and promising cancer treatment strategies. In gynecologic malignancies, potential therapeutic targeted agents include antiangiogenic agents, poly (ADP-ribose) polymerase (PARP) inhibitors, tumor-intrinsic signaling pathway inhibitors, selective estrogen receptor downregulators, and immune checkpoint inhibitors. In this article, we provide a comprehensive review of the clinical evidence of targeted agents in gynecological cancers and discuss the future implication.

Therapeutic Targets and Opportunities in Endometrial Cancer: Update on Endocrine Therapy and Nonimmunotherapy Targeted Options

Worldwide, the incidence of endometrial cancer is increasing. Although the prognosis remains good for patients diagnosed with early-stage disease, for those diagnosed with recurrent or metastatic disease, options have been limited, and prognosis is short. Optimizing and identifying new well-tolerated treatments for women living with endometrial cancer is a top priority. A new era is dawning where we are starting to see the integration of clinically relevant genomic and pathologic data to inform and refine treatment strategies for women with endometrial cancer. Here, we focus on reviewing nonimmunotherapy-based targeted treatment options and emerging directions for women with endometrial cancer.

Model-Assisted Designs for Early-Phase Clinical Trials: Simplicity Meets Superiority

Drug development enterprise is struggling because of prohibitively high costs and slow progress. There is urgent need for adoption of novel adaptive designs to improve the efficiency and success of clinical trials. A major barrier is that many conventional designs are inadequate for modern drug development, yet most novel adaptive designs are difficult to understand, require complicated statistical modeling, demand complex computation, and need expensive infrastructure for implementation. The objective of this article is to introduce and review a class of novel adaptive designs, known as model-assisted designs, to remove this barrier and increase the use of novel adaptive designs. Model-assisted designs enjoy superior performance comparable to more complicated, model-based adaptive designs, but their decision rule can be pretabulated and included in the protocol-thus implemented as simply as the conventional designs. We review state-of-the-art model-assisted designs for phase I clinical trials for single-agent, drug-combination and late-onset toxicity scenarios. We also briefly introduce model-assisted designs for phase II trials to handle binary, coprimary endpoints and delayed response. Freely available user-friendly software and trial examples (trialdesign.org) facilitate the adoption of model-assisted designs.

An optimal Bayesian predictive probability design for phase II clinical trials with simple and complicated endpoints

Most existing phase II clinical trial designs focus on conventional chemotherapy with binary tumor response as the endpoint. The advent of novel therapies, such as molecularly targeted agents and immunotherapy, has made the endpoint of phase II trials more complicated, often involving ordinal, nested, and coprimary endpoints. We propose a simple and flexible Bayesian optimal phase II predictive probability (OPP) design that handles binary and complex endpoints in a unified way. The Dirichlet-multinomial model is employed to accommodate different types of endpoints. At each interim, given the observed interim data, we calculate the Bayesian predictive probability of success, should the trial continue to the maximum planned sample size, and use it to make the go/no-go decision. The OPP design controls the type I error rate, maximizes power or minimizes the expected sample size, and is easy to implement, because the go/no-go decision boundaries can be enumerated and included in the protocol before the onset of the trial. Simulation studies show that the OPP design has satisfactory operating characteristics.

Angiopoietin-1 and Angiopoietin-2 Inhibitors: Clinical Development

PURPOSE OF REVIEW

The purpose of this review is to discuss the current understanding of the Tie2-angiopoietin system and its role in tumor growth and metastasis. This review also focuses on preclinical and clinical data published to date that have evaluated Tie2-angiopoietin inhibition.

RECENT FINDINGS

Tie2 inhibition has shown significant promise in preclinical models, notable for decreased tumor burden and fewer sites of metastatic disease across various malignancies. However, data from human clinical trials have shown more mixed results. Trebananib, rebastanib, and MEDI3617 are the three Tie2-angiopoietin inhibitors that have been most widely evaluated in phase I and II trials. Further investigation into these therapies is ongoing. The Tie2-angiopoietin pathway continues to show promise in preclinical and some clinical trials, including studies on recurrent or metastatic breast and renal cell carcinomas. Further evaluation of these therapies, however, is warranted to better understand their optimal clinical utility.

Clinical and prognostic significance of circulating levels of angiopoietin-1 and angiopoietin-2 in hepatocellular carcinoma

Angiopoietin-1 (Ang-1) and angiopoietin-2 (Ang-2) play critical roles in angiogenesis in hepatocellular carcinoma (HCC). In addition, recent data suggest that Ang-1/Ang-2 are involved in regulating the immune response. The aim of our study was to explore the clinical prognostic significance of plasma Ang-1 and Ang-2 in HCC. We prospectively enrolled and collected data and blood samples from 767 HCC patients treated at MD Anderson Cancer Center between 2001 and 2014. Controls consisted of cirrhotic patients (n = 75) and healthy volunteers (n = 200). The cutoff value was the median level of each angiogenic factor. Overall survival (OS) was estimated by Kaplan–Meier curves and compared by the log-rank test. Higher plasma Ang-2 was significantly associated with advanced clinicopathologic features of advanced HCC and lower OS. Median OS was 61.8 months (95% confidence interval [CI], 45.1–78.5 months) for low Ang-2 compared with 28.5 months (95% CI, 24.8–32.1 months) for high Ang-2 (p < 0.001). In contrast, higher Ang-1 was associated with longer OS. Median OS was 37.2 months (95% CI, 31.0–43.4 months) for high Ang-1 compared with 26.2 months (95% CI, 22.2–30.3 months) for those with low Ang-1 (p = 0.043). In conclusion, our findings indicate that plasma Ang-1 and Ang-2 levels are potential diagnostic and prognostic biomarkers in HCC.

Management Strategies for Recurrent Endometrial Cancer

INTRODUCTION

Endometrial cancer is the most common gynecologic malignancy in the developed world, and its incidence is increasing. Mortality from this cancer has not improved in recent decades and is primarily driven by high-grade carcinomas that are more likely to present at an advanced stage and ultimately are more likely to recur. The prognosis for recurrent endometrial cancer is poor, especially for the 50% of these women that present with extrapelvic disease recurrence. As a standard of care, recurrent disease has been treated with platinum-based chemotherapy; however, new therapies are emerging as we identify drivers of proliferation and metastasis at the cellular and molecular levels. Areas Covered: We review currently available data for the management of recurrent endometrial cancer, with a focus on systemic treatment of recurrent disease. We discuss the available evidence for first-line, second-line, and subsequent systemic therapy and discuss emerging therapeutic targets including their biologic plausibility and early clinical data. Expert Commentary: Endometrial cancer, though prevalent, remains underfunded and understudied. Recurrent and metastatic disease remains difficult to treat, and prospective randomized data are limited. Our ability to reduce mortality due to this cancer is dependent on identifying new and effective therapeutic strategies for recurrent disease.

Strategies for clinical development of monoclonal antibodies beyond first-in-human trials: tested doses and rationale for dose selection

BACKGROUND

Our previous survey on first-in-human trials (FIHT) of monoclonal antibodies (mAbs) showed that, due to their limited toxicity, the recommended phase II dose (RP2D) was only tentatively defined.

METHODS

We identified, by MEDLINE search, articles on single-agent trials of mAbs with an FIHT included in our previous survey. For each mAb, we examined tested dose(s) and dose selection rationale in non-FIHTs (NFIHTs). We also assessed the correlation between doses tested in the registration trials (RTs) of all FDA-approved mAbs and the corresponding FIHT results.

RESULTS

In the 37 dose-escalation NFIHTs, the RP2D indication was still poorly defined. In phase II-III NFIHTs (n=103 on 37 mAbs), the FIHT RP2D was the only dose tested for five mAbs. For 16 mAbs, only doses different from the FIHT RP2D or the maximum administered dose (MAD) were tested and the dose selection rationale infrequently indicated. In the 60 RTs on 27 FDA-approved mAbs with available FIHT, the FIHT RP2D was tested only for two mAbs, and RT doses were much lower than the FIHT MAD.

CONCLUSIONS

The rationale beyond dose selection in phase II and III trials of mAbs is often unclear in published articles and not based on FIHT data.

Paclitaxel, Carboplatin, and Bevacizumab in Advanced and Recurrent Endometrial Carcinoma

OBJECTIVE

The aim of this study was to evaluate the efficacy of adding bevacizumab to paclitaxel and carboplatin and as maintenance in a larger cohort of patients with advanced or recurrent endometrial carcinoma.

METHODS

We retrospectively identified endometrial cancer patients treated with paclitaxel (175 mg/m per 3 hours), carboplatin (area under the curve, 5) and bevacizumab (15 mg/kg) and maintenance bevacizumab treated in a post-protocol treatment cohort and evaluated them with our previously published phase 2 trial of this regimen.

RESULTS

Twenty-seven additional patients were identified; 19 received the regimen as first-line therapy, and 8 received the regimen as second-line therapy after prior paclitaxel and carboplatin. The 19 patients who received first-line therapy were analyzed alone and with the 15 patients enrolled on protocol. The 2 cohorts were similar with respect to risk factors. Overall survival curves were not statistically different between the protocol and the postprotocol patients (log-rank test; P > 0.1). Collectively, a total of 266 courses (median, 6 courses; range, 1-20 courses) of carboplatin, paclitaxel, and bevacizumab combination therapy and 305 courses (median, 16 courses; range, 0-45courses) of bevacizumab maintenance therapy were administered as first-line therapy. Collectively, the median progression-free survival was 20 months, and median overall survival was 56 months. Among 29 patients with measurable disease, the response rate was 82.8% (95% confidence interval, 69.0%-96.5%; 15 complete responses and 9 partial responses). Among the 8 patients who received paclitaxel and carboplatin and bevacizumab as second-line therapy after paclitaxel and carboplatin, the response rate was 87.5% (6 complete responses, 1 partial response). Their median progression-free survival and median overall survival were not reached after a median follow-up of 23.5 months.

CONCLUSIONS

Although there are inherent limitations to small retrospective studies, this second analysis confirms the high response rate, progression-free survival, and overall survival in the bevacizumab, paclitaxel, and carboplatin regimen as first-line therapy in advanced and recurrent endometrial carcinoma.

Peptibodies: An elegant solution for a long-standing problem

Chimeric proteins composed of a biologically active peptide and a fragment crystallizable (Fc) domain of immunoglobulin G (IgG) are known as peptibodies. They present an extended half-life due to neonatal Fc receptor (FcRn) salvage pathway, a decreased renal clearance rate owing to its increased size (≈70 kDa) and, depending on the peptide used in the design of the peptibody, an active-targeting moiety. Also, the peptides therapeutic activity is boosted by the number of peptides in the fusion protein (at least two peptides) and to some peptides' alterations. Peptibodies are mainly obtained through recombinant DNA technology. However, to improve peptide properties, "unnatural" changes have been introduced to the original peptides' sequence, for instance, the incorporation of D- or non-natural amino acid residues or even cyclization thus, limiting the application of genetic engineering in the production of peptibodies, since these peptides must be obtained via chemical synthesis. This constrains prompted the development of new methods for conjugation of peptides to Fc domains. Another challenge, subject of intense research, relates to the large-scale production of such peptibodies using these new techniques, which can be minimized by their proved value. To date, two peptibodies, romiplostim and dulaglutide, have been approved and stay as the standard of care in their areas of action. Furthermore, a considerable number of peptibodies are currently in preclinical and clinical development.

Phase 2 and biomarker study of trebananib, an angiopoietin-blocking peptibody, with and without bevacizumab for patients with recurrent glioblastoma

BACKGROUND

Angiopoietins contribute to tumor angiogenesis and may be upregulated as a compensatory factor after vascular endothelial growth factor (VEGF) blockade. The authors performed a phase 2 and biomarker study to evaluate trebananib, an angiopoietin 1 and angiopoietin 2 blocking peptibody, with and without bevacizumab in patients with recurrent glioblastoma.

METHODS

Forty-eight patients who had bevacizumab-naive, recurrent glioblastoma were treated with trebananib (30 mg/kg weekly) as single agent (n = 11) or combined with bevacizumab (n = 37). The primary endpoint was 6-month progression-free survival rate as determined by investigator review. Circulating biomarker levels were assessed before and after study therapy.

RESULTS

Trebananib was well tolerated as monotherapy and did not enhance bevacizumab-associated toxicity. Trebananib had no single-agent activity, and all treated patients exhibited progressive disease within 2 months. The 6-month progression-free survival rate for trebananib plus bevacizumab was 24.3% (95% confidence interval [CI], 12.1%-38.8%); whereas the median overall survival was 9.5 months (95% CI, 7.5-4.7 months), and the 12-month overall survival rate was 37.8% (95% CI, 22.6%-53.0%). Baseline and post-treatment changes in circulating vascular VEGF and interleukin-8 levels were correlated with survival among patients who received trebananib plus bevacizumab.

CONCLUSIONS

Angiopoietin 1 and angiopoietin 2 inhibition with trebananib was ineffective as monotherapy and did not enhance the ability of VEGF blockade with bevacizumab to improve the outcomes of patients with recurrent glioblastoma. Cancer 2018;124:1438-48. © 2017 American Cancer Society.

Treatment strategies for endometrial cancer: current practice and perspective

PURPOSE OF REVIEW

Endometrial cancer incidence is increasing in North America and is a major cause of morbidity and mortality in women. We review recent literature published on treatment of endometrial cancer and highlight areas of active interest.

RECENT FINDINGS

There has been movement toward minimal invasive surgery at diagnosis; lymph node staging remains controversial and continues to be investigated. Progress has been made to establish consensus on endometrial cancer risk classification to promote consistency for future trial design. Molecular characterization of endometrial cancer and its integration into clinicopathological profiling to develop predictive biomarkers for treatment selection are active areas of research. Optimal adjuvant treatment strategy in high-risk endometrial cancer remains to be defined with recognition of treatment-related toxicity. Despite encouraging results in drug development for treatment of advanced/recurrent endometrial cancer, no targeted therapies beyond hormonal therapy are approved. There is an urgent need for scientifically validated therapy with predictive biomarkers.

SUMMARY

Our understanding of endometrial cancer has evolved through improvements in molecular biology, allowing improved definition of target-specific therapies. The precise role and sequence of conventional and targeted therapies, including immunotherapy, will require careful attention to the design of clinical trials with translational emphasis to allow the discovery, validation, and implementation of predictive biomarkers into clinical care.

Clinical trials in gynecologic oncology: Past, present, and future

The Gynecologic Oncology Group has historically performed ground-breaking, practice-changing clinical trials in women's cancers. The current standard of care for initial treatment of ovarian, endometrial, cervical, and trophoblastic cancers was determined by clinical trials completed within this cooperative group structure. For example, trial GOG-0111 set the standard for combining platinum and taxane chemotherapy in ovarian cancer, and more recently GOG-0240 provided evidence for adding bevacizumab to chemotherapy for women with advanced cervical cancer. The landscape of clinical trial design has markedly changed in recent decades, with a clear emphasis on streamlining drug development towards specific patient populations and indications for investigational agents. Translational science in gynecologic cancers can set the stage for rapid and efficient introduction of new therapies for our patients. The gynecologic oncology community of researchers and clinicians is well positioned to enter into the new era of drug development, with breakthrough discoveries increasing each year. It is clear that we must incorporate smarter clinical trial design to get the right drugs to the right patients expeditiously, so we can continue to improve outcome for women with gynecologic cancers.

New therapies for advanced, recurrent, and metastatic endometrial cancers

Endometrial cancer is the most common gynecologic malignancy in the United States, accounting for 6% of cancers in women. In 2017, an estimated 61,380 women were diagnosed with endometrial cancer, and approximately 11,000 died from this disease. From 1987 to 2008, there was a 50% increase in the incidence of endometrial cancer, with an approximate 300% increase in the number of associated deaths. Although there are many chemotherapeutic and targeted therapy agents approved for ovarian, fallopian tube and primary peritoneal cancers, since the 1971 approval of megestrol acetate for the palliative treatment of advanced endometrial cancer, only pembrolizumab has been Food and Drug Administration (FDA)-approved for high microsatellite instability (MSI-H) or mismatch repair deficient (dMMR) endometrial cancer; this highlights the need for new therapies to treat advanced, recurrent, metastatic endometrial cancer. In this review, we discuss current and emerging treatment options for endometrial cancer, including chemotherapy, targeted therapy, and immunotherapy. The National Cancer Institute (NCI) and others are now focusing their efforts on the design of scientifically rational targeted therapy and immunotherapy trials for specific molecular phenotypes of endometrial cancer. This is essential for the advancement of cancer care for women, which is threatened by a severe enrollment decline of approximately 80% for gynecologic oncology clinical trials.

Efficacy of combination chemotherapy using irinotecan and nedaplatin for patients with recurrent and refractory endometrial carcinomas: preliminary analysis and literature review

PURPOSE

We aimed to retrospectively evaluate the efficacy and toxicity of an irinotecan hydrochloride (CPT) and nedaplatin (N) combination therapy for recurrent and refractory endometrial carcinoma, administered based on UGT1A1 genotype.

METHODS

Between 2009 and 2017, 21 patients who received CPT-N therapy for recurrent endometrial carcinoma as second- or third-line chemotherapy at our hospital were identified. The CPT-N regimen included 40-70 mg/m² of CPT-11 on days 1, 8, and 15, and 50 mg/m² of nedaplatin on day 1, q4 weeks.

RESULTS

The median patient age was 63 years. The number of prior chemotherapeutic regimens ranged from 1 to 2. Two patients had prior pelvic irradiation. The response rate [ratio of complete remission (CR) to partial remission (PR)] of CPT-N therapy was 3 of 21 (14.3%), and clinical benefit rate (CBR) [the combined percentages of CR, PR, and stable disease (SD)] was 9 of 21 (42.8%). Toxicities included grade 3 neutropenia [4 (19.0%) cases], grade 3 febrile neutropenia [2 (9.5%) cases], and grade 3 diarrhea [3 (14.3%) cases]; all resolved with conservative treatment. Patients with a wild-type UGT1A1 status received higher doses of CPT-11 (p = 0.048) and had similar RR and CBR compared to those with a UGT1A1*6 and *28 status. There were no significant differences in frequencies of hematological or non-hematological toxicities, regardless of UGT1A1 status.

CONCLUSIONS

The CPT-N regimen for recurrent and refractory endometrial carcinoma had tolerable side effects and significant efficacy. This regimen is a viable treatment option for endometrial carcinoma.

Chemotherapy for Endometrial Cancer in Adjuvant and Advanced Disease Settings

: Level I evidence exists for use of adjuvant chemotherapy in stage IIIC endometrial cancer (positive lymph nodes), although results of randomized trials have varied. Chemotherapy is also often recommended for high-risk subsets of stage I disease, such as serous carcinomas, although prospective trial data to validate this practice are lacking. Carboplatin plus paclitaxel is the current standard regimen, based on extrapolation of data from the metastatic setting. Several clinical trials have compared adjuvant pelvic radiotherapy alone to a combination of radiotherapy and chemotherapy with mixed results. One of the largest of these trials, Postoperative Radiation Therapy in Endometrial Carcinoma 3 (PORTEC-3), has completed accrual and is awaiting data maturation. Metastatic disease is not curable. For tumors of low-grade endometrioid histology with a prolonged time to recurrence, endocrine therapy with a progestin-based regimen is appropriate. Chemotherapy will be used in most other cases, and the standard first-line regimen is carboplatin and paclitaxel. Few chemotherapy agents have been shown to produce meaningful response rates in the second-line setting. Molecularly targeted therapies such as mTOR inhibitors and antiangiogenic agents including bevacizumab have been studied but their role in the armamentarium remains uncertain.

IMPLICATIONS FOR PRACTICE

Following surgical resection and staging for endometrial cancer, adjuvant chemotherapy with carboplatin and paclitaxel can be administered to patients with a high risk for recurrence. This includes patients with stage IIIC disease with positive lymph nodes, and high-risk subsets of stage I disease such as serous carcinomas. In the metastatic setting, endocrine therapy can be considered, particularly for patients with lower-grade disease and a prolonged time to recurrence. Combined therapy with carboplatin and paclitaxel is the standard of care used for front-line chemotherapy. Antiangiogenic agents are clearly active, but how they should be integrated into treatment is not yet determined. Immunotherapy is a promising direction for patients with mismatch repair-deficient or polymerase ε-mutated tumors.

Half-life extended biotherapeutics

INTRODUCTION

Many of the biotherapeutics approved or under development suffer from a short half-life necessitating frequent applications in order to maintain a therapeutic concentration over an extended period of time. The implementation of half-life extension strategies allows the generation of long-lasting therapeutics with improved pharmacokinetic and pharmacodynamic properties.

AREAS COVERED

This review gives an overview of the different half-life extension strategies developed over the past years and their application to generate next-generation biotherapeutics. It focuses on srategies already used in approved drugs and drugs that are in clinical development. These strategies include those aimed at increasing the hydrodynamic radius of the biotherapeutic and strategies which further implement recycling by the neonatal Fc receptor (FcRn).

EXPERT OPINION

Half-life extension strategies have become an integral part of development for many biotherapeutics. A diverse set of these strategies is available for the fine-tuning of half-life and adaption to the intended treatment modality and disease. Currently, half-life extension is dominated by strategies utilizing albumin binding or fusion, fusion to an immunoglobulin Fc region and PEGylation. However, a variety of alternative strategies, such as fusion of flexible polypeptide chains as PEG mimetic substitute, have reached advanced stages and offer further alternatives for half-life extension.

Targeting dormant micrometastases: rationale, evidence to date and clinical implications

In spite of decades of research, cancer survival has increased only modestly. This is because most research is based on models of primary tumors. Slow recognition has begun that disseminated, dormant cancer cells (micrometastatic cells) that are generally resistant to chemotherapy are the culprits in recurrence, and until these are targeted effectively we can expect only slow progress in increasing overall survival from cancer. This paper reviews efforts to understand the mechanisms by which cancer cells can become dormant, and thereby identify potential targets and drugs either on the market or in clinical trials that purport to prevent metastasis. This review targets the most recent literature because several excellent reviews have covered the literature from more than two years ago. The paper also describes recent work in the authors' laboratories to develop a screening-based approach that does not require understanding of mechanisms of action or the molecular target. Success of this approach shows that targeting micrometastatic cells is definitely feasible.