Pazopanib and Oral Cyclophosphamide in Women With Platinum-Resistant or -Refractory Epithelial Ovarian Cancer

Impact of Bevacizumab on Clinical Outcomes in Patients With Platinum-resistant Relapsed Ovarian Cancer

BACKGROUND/AIM

Over the past several decades, new anti-cancer drugs have been developed for the treatment of epithelial ovarian cancer. The development of drugs has led to changes in improving the prognosis of ovarian cancer patients. One of these drugs, bevacizumab, is used for advanced or recurrent ovarian cancer. In this study, we aimed to evaluate survival improvement in patients with platinum-resistant relapsed epithelial ovarian cancer (PR-ROC) after introduction of bevacizumab in real world experience.

PATIENTS AND METHODS

We retrospectively divided patients with PR-ROC into two groups: bevacizumab plus chemotherapy (BEV-CT group) and chemotherapy alone (CT group). Progression-free survival (PFS), the primary endpoint, between two groups was compared to evaluate whether survival outcomes were improved. In addition, overall survival (OS) was also compared.

RESULTS

A total of 154 patients were included in the study: 57 and 97 patients in the BEV-CT and CT groups, respectively. OS was significantly longer in the BEV-CT group than in the CT group. The use of bevacizumab was identified as a favorable prognostic factor for OS. In a subgroup analysis confined to second-line chemotherapy, PFS and OS were statistically different between groups. More patients in the CT group suffered hematologic adverse events of grade 3 or above than patients in the BEV-CT group.

CONCLUSION

In a real-world clinical setting, introduction of bevacizumab led to improvement of OS in patients with PR-ROC with a tolerable toxicity.

Drug-Resistant Epithelial Ovarian Cancer: Current and Future Perspectives

Epithelial ovarian cancer (EOC) is a complex disease with diverse histological subtypes, which, based on the aggressiveness and course of disease progression, have recently been broadly grouped into type I (low-grade serous, endometrioid, clear cell, and mucinous) and type II (high-grade serous, high-grade endometrioid, and undifferentiated carcinomas) categories. Despite substantial differences in pathogenesis, genetics, prognosis, and treatment response, clinical diagnosis and management of EOC remain similar across the subtypes. Debulking surgery combined with platinum-taxol-based chemotherapy serves as the initial treatment for High Grade Serous Ovarian Carcinoma (HGSOC), the most prevalent one, and for other subtypes, but most patients exhibit intrinsic or acquired resistance and recur in short duration. Targeted therapies, such as anti-angiogenics (e.g., bevacizumab) and PARP inhibitors (for BRCA-mutated cancers), offer some success, but therapy resistance, through various mechanisms, poses a significant challenge. This comprehensive chapter delves into emerging strategies to address these challenges, highlighting factors like aberrant miRNAs, metabolism, apoptosis evasion, cancer stem cells, and autophagy, which play pivotal roles in mediating resistance and disease relapse in EOC. Beyond standard treatments, the focus of this study extends to alternate targeted agents, including immunotherapies like checkpoint inhibitors, CAR T cells, and vaccines, as well as inhibitors targeting key oncogenic pathways in EOC. Additionally, this chapter covers disease classification, diagnosis, resistance pathways, standard treatments, and clinical data on various emerging approaches, and advocates for a nuanced and personalized approach tailored to individual subtypes and resistance mechanisms, aiming to enhance therapeutic outcomes across the spectrum of EOC subtypes.

Efficacy and Safety of Oral Metronomic Chemotherapy in Recurrent Refractory Advanced Gynaecological Cancer: An Experience From the Regional Cancer Centre of Eastern India

INTRODUCTION

The outcome of recurrent/metastatic gynaecological malignancy has drastically improved with the introduction of poly(ADP-ribose) polymerase inhibitors and immunotherapy, but the use of these drugs in routine practice is complicated due to access barriers and their high cost in developing countries. The purpose of this study is to present the clinical response, outcome and safety of oral metronomic chemotherapy (OMCT) in resource-limited, financially constrained populations.

METHODS

This is a retrospective study on patients with advanced gynaecological cancer treated at Chittaranjan National Cancer Institute, Kolkata, India, from 2021 to 2023. The patients were treated with one of these two regimens: a split-dose course of cyclophosphamide (50 mg orally once daily for 21 days) and capecitabine (500 mg twice daily continuous) or a fixed-dose combination (capecitabine 1800 mg and cyclophosphamide 80 mg orally for 14 days in every 21 days) until disease progression or unacceptable toxicities occurred. All data was captured from the hospital's medical records until June 2023. Toxicity data was reported per the Common Terminology Criteria for Adverse Events (CTCAE) v5.1, and progression-free survival (PFS) was estimated using Kaplan-Meier methods.

RESULTS

Among 34 screened patients, 10 were excluded due to noncompliance. This study analysed 24 patients with a median age at diagnosis of 56 years (IQ range 44-75). Sixteen (67%) patients were at stage IV disease with an Eastern Cooperative Oncology Group (ECOG) performance status of 3. Ovarian and cervical cancers were 80% and 20%, respectively; among them, 16 (67%) patients were platinum-refractory. Forty-two per cent of patients received three lines of chemotherapy before OMCT. A split course versus fixed dose was given to 67% versus 33% of the population; the best responses per the Response Evaluation Criteria in Solid Tumours v1.1 were complete response in 12%, partial response in 67% and stable disease in 21%. The most common toxicities were grade I anaemia (54%), grade I chemotherapy-induced nausea and vomiting (46%), grade I fatigue (42%) and grade I neutropenia (21%). Twenty-five per cent of patients were offered next-line systemic therapy after progression. The entire cohort had a median PFS of nine months (95%, CI: 5.2-12.7). Cox regression analysis identified a median PFS of 12 months (95%, CI: 6.2-17.7) among platinum-refractory groups.

CONCLUSION

OMCT was a well-tolerated, affordable regimen with durable clinical response and survival outcome (median PFS of nine months) in recurrent, refractory advanced gynaecological cancer and can be offered to patients at resource-limited centres.

Metronomic chemotherapy in ovarian cancer

Translational research and the development of targeted therapies have transformed the therapeutic landscape in epithelial ovarian cancer over the last decade. However, recurrent ovarian cancer continues to pose formidable challenges to therapeutic interventions, necessitating innovative strategies to optimize treatment outcomes. Current research focuses on the development of pharmaceuticals that target potential resistance pathways to DNA repair pathways. However, the cost and toxicity of some of these therapies are prohibitive and majority of patients lack access to clinical trials. Metronomic chemotherapy, characterized by the continuous administration of low doses of chemotherapeutic agents without long treatment breaks, has emerged as a promising approach with potential implications beyond recurrent setting. It acts primarily by inhibition of angiogenesis and activation of host immune system. We here review the mechanism of action of metronomic chemotherapy, as well as its current role, limitations, and avenues for further research in the management of epithelial ovarian cancer.

Cancer Treatment-Related Cardiovascular Toxicity in Gynecologic Malignancies: JACC: CardioOncology State-of-the-Art Review

Improvements in early detection and treatment of gynecologic malignancies have led to an increasing number of survivors who are at risk of long-term cardiac complications from cancer treatment. Multimodality therapies for gynecologic malignancies, including conventional chemotherapy, targeted therapeutics, and hormonal agents, place patients at risk of cancer therapy-related cardiovascular toxicity during and following treatment. Although the cardiotoxicity associated with some female predominant cancers (eg, breast cancer) have been well recognized, there has been less recognition of the potential adverse cardiovascular effects of anticancer therapies used to treat gynecologic malignancies. In this review, the authors provide a comprehensive overview of the cancer therapeutic agents used in gynecologic malignancies, associated cardiovascular toxicities, risk factors for cardiotoxicity, cardiac imaging, and prevention strategies.

Metronomic Chemotherapy Based on Topotecan or Topotecan and Cyclophosphamide Combination (CyTo) in Advanced, Pretreated Ovarian Cancer

Patients with advanced ovarian cancer (OC) have a detrimental prognosis. The options for systemic treatment of advanced OC in later lines of treatment are limited by the availability of active therapies and their applicability to often fragile, exhausted patients with poor performance status. Metronomic chemotherapy (MC) is a concept of a continuous administration of cytotoxic drugs, which is characterized by multidirectional activity (anti-proliferative, anti-angiogenic, and anti-immunosuppressive) and low toxicity. We have performed a retrospective analysis of consecutive, advanced, chemo-refractory OC patients treated with MC based on single-agent topotecan (1 mg p.o. q2d) or on a topotecan (1 mg q2d) and cyclophosphamide (50 mg p.o. qd) combination (CyTo). Metronomic chemotherapy demonstrated promising activity, with 72% and 86% of patients achieving biochemical or objective disease control and 18% and 27% of patients achieving a biochemical or objective response, respectively. The median PFS in the whole population was 3.65 months, but the median PFS in patients with a biochemical response to MC (18.2% of patients) reached 10.7 months. The study also suggested that overweight or obese patients had significantly better outcomes on MC than patients with BMI <25 kg/m². This article is the first report in the literature on metronomic chemotherapy based on a topotecan + cyclophosphamide combination (CyTo). The CyTo regimen demonstrated safety, clinical activity, and potential broad clinical applicability in advanced OC patients and will be evaluated in a forthcoming clinical trial.

Therapy for Recurrent High-Grade Epithelial Ovarian Cancer—The Current Status and Future Trends

Ovarian malignancy is the seventh most frequently diagnosed cancer among women. The most common type is epithelial ovarian cancer. Several subtypes with distinct biological and molecular properties exist, and there is inconsistency in availability of and access to different modalities of treatment. The standard first-line management is combining surgery and platinum-based chemotherapy. Most of them are diagnosed at an advanced stage due to which they have poor outcomes. The existing screening tests have a low predictive value. Even with the best available upfront treatment, high rates of recurrences are observed. As a result, there have been major advances in the treatment of recurrences with the development of anti-angiogenic agents and PARP inhibitors. It has led to the improvement in survival and quality of life among the relapsed epithelial ovarian cancers. This review is focused on the management of recurrent epithelial ovarian cancers and future directions based on current evidence. The application of a personalized and structured approach will meaningfully bring changes in the paradigm of care in these groups of patients.

Targeting Tyrosine Kinases in Ovarian Cancer: Small Molecule Inhibitor and Monoclonal Antibody, Where Are We Now?

Ovarian cancer is one of the most lethal gynaecological malignancies worldwide. Despite high success rates following first time treatment, this heterogenous disease is prone to recurrence. Oncogenic activity of receptor tyrosine kinases is believed to drive the progression of ovarian cancer. Here we provide an update on the progress of the therapeutic targeting of receptor tyrosine kinases in ovarian cancer. Broadly, drug classes that inhibit tyrosine kinase/pathways can be classified as small molecule inhibitors, monoclonal antibodies, or immunotherapeutic vaccines. Small molecule inhibitors tested in clinical trials thus far include sorafenib, sunitinib, pazopanib, tivantinib, and erlotinib. Monoclonal antibodies include bevacizumab, cetuximab, pertuzumab, trastuzumab, and seribantumab. While numerous trials have been carried out, the results of monotherapeutic agents have not been satisfactory. For combination with chemotherapy, the monoclonal antibodies appear more effective, though the efficacy is limited by low frequency of target alteration and a lack of useful predictive markers for treatment stratification. There remain critical gaps for the treatment of platinum-resistant ovarian cancers; however, platinum-sensitive tumours may benefit from the combination of tyrosine kinase targeting drugs and PARP inhibitors. Immunotherapeutics such as a peptide B-cell epitope vaccine and plasmid-based DNA vaccine have shown some efficacy both as monotherapeutic agents and in combination therapy, but require further development to validate current findings. In conclusion, the tyrosine kinases remain attractive targets for treating ovarian cancers. Future development will need to consider effective drug combination, frequency of target, and developing predictive biomarker.

Pazopanib in rare histologies of metastatic soft tissue sarcoma

Background

Uncommon histopathological subtypes account for less than 5% cases of soft tissue sarcoma (STS) and unclassified STSs comprise another 16%, these are often chemotherapy-resistant, with a dismal outcome in unresectable/metastatic disease. Prospective studies on the use of pazopanib in this cohort of patients are lacking in the literature. Here, we describe the safety and efficacy of pazopanib in rare histologies of advanced STS.

Materials and methods

We conducted a retrospective study at two tertiary cancer centres in India, evaluating 33 cases of rare subtypes of STS, who received pazopanib as per institutional protocol between January 2013 and December 2019. Patients who received pazopanib for unresectable/metastatic disease were enrolled in this study for clinicopathologic features, treatment outcome and evaluation of prognostic factors.

Results

Out of 33 patients, there were seven cases of undifferentiated pleomorphic sarcoma, four cases each of myxofibrosarcoma, epithelioid sarcoma and malignant peripheral nerve sheath tumour, three cases each of haemangiopericytoma and spindle cell sarcoma, two cases of haemangioendothelioma and a case each of clear cell sarcoma, retroperitoneal sarcoma, angiosarcoma and pleomorphic rhabdomyosarcoma-adult type. The objective response rate was 27%. Most of the patients (67%) received pazopanib in second or subsequent lines of therapy. The majority (70%) were started at a lower dose of 400/600 mg and only 43% of these (10/23) could be escalated to a full dose of 800 mg based on tolerance. On univariate analysis, pazopanib’s starting dose didn’t predict progression-free survival (PFS)/overall survival (OS)/response rate. At a median duration of follow-up of 18.8 months (range 1.9–150.4 months), the median PFS and median OS were 10.3 months (95% confidence interval (CI): 5.9–14.8) and 17.8 months (95% CI: 10.7–29.3), respectively. 27% of the patients experienced grade ¾ toxicities, 12% required dose modification of pazopanib and 21% needed permanent discontinuation due to toxicity.

Conclusion

Our study shows that pazopanib is active in rare subtypes of STS.

Platinum-Pemetrexed Chemotherapy for Recurrent Ovarian Cancer (ROC): A Single Center Experience

In this retrospective analysis of 36 patients with recurrent ovarian cancer (ROC) treated with platinum pemetrexed doublet ± bevacizumab, the median age was 54.5 years (47-60) and 33 (91.7%) had serous histology. The overall response rate [ORR = complete (CR)+partial (PR) response] was 83.3%. At a median follow-up of 16 months, the median PFS was 13.8 months (95% CI: 10.849-20.580) and median OS 30.6 months, (95% CI: 21.46 months-NR). The incidence of Grade 3/4 anemia, thrombocytopenia, neutropenia and non-hematological toxicity was 19.4%, 3.9%, 16.6%, and 8.3%. Platinum pemetrexed chemotherapy in ROC is safe and effective treatment option.

Pazopanib based oral metronomic therapy for platinum resistant/refractory epithelial ovarian cancer: A phase II, open label, randomized, controlled trial

BACKGROUND

Treatment of patients with platinum resistant/refractory epithelial ovarian cancer (EOC) is an unmet need. We evaluated the role of oral metronomic therapy in this setting.

PATIENTS AND METHODS

Between October 2017 and September 2019 seventy five patients with platinum resistant/refractory EOC were enrolled. Patients received oral etoposide (50 mg, day 1 to 14, cyclophosphamide 50 mg, day 1 to 28, every 4 weeks (Arm A, n = 38). Patients in Arm- B (n = 37) received Pazopanib (400 mg once daily) in addition to etoposide and cyclophosphamide. Quality of life (QoL) was evaluated using the EORTC questionnaire. Serum VEGF and PDGF were estimated at baseline, after 3rd and 6th cycle. The primary endpoint was progression free survival (PFS). Secondary endpoints were overall survival (OS), toxicity and QoL.

RESULTS

Patients characteristics were well matched. Median PFS was higher in arm B, 5.1 months (95% CI 3.13 to10.33) compared to 3.4 months (95% CI 3.0 to 6.53) in arm A, p = 0.045. Median OS has 'not reached' in Arm B compared to 11.2 months (95% CI, 5.66 - not reached) in arm A, p = 0.032. Therapy was tolerated well; oral mucositis (p = 0.36) and fatigue (p = 0.08) being more in arm B. QoL assessment revealed modest improvement in 'symptom scales' in Arm B. Serum VEGF and PDGF levels decreased with therapy in both arms (Arm A-p < 0.0001, Arm B-p < 0.016).

CONCLUSION

Addition of pazopanib to etoposide and cyclophosphamide could be a novel oral combination for metronomic therapy for platinum resistant/refractory EOC.

TRIAL REGISTRATION

CTRI/2017/10/010219.