Timing isn't everything: an analysis of when to start salvage chemotherapy in ovarian cancer

Current Advances in PD-1/PD-L1 Blockade in Recurrent Epithelial Ovarian Cancer

Immunotherapies have revolutionized the treatment of a variety of cancers. Epithelial ovarian cancer is the most lethal gynecologic malignancy, and the rate of advanced tumor progression or recurrence is as high as 80%. Current salvage strategies for patients with recurrent ovarian cancer are rarely curative. Recurrent ovarian cancer is a “cold tumor”, predominantly due to a lack of tumor antigens and an immunosuppressive tumor microenvironment. In trials testing programmed death-1 (PD-1)/programmed death ligand 1 (PD-L1) blockade as a monotherapy, the response rate was only 8.0-22.2%. In this review, we illustrate the status of cold tumors in ovarian cancer and summarize the existing clinical trials investigating PD-1/PD-L1 blockade in recurrent ovarian cancer. Increasing numbers of immunotherapy combination trials have been set up to improve the response rate of EOC. The current preclinical and clinical development of immunotherapy combination therapy to convert an immune cold tumor into a hot tumor and their underlying mechanisms are also reviewed. The combination of anti-PD-1/PD-L1 with other immunomodulatory drugs or therapies, such as chemotherapy, antiangiogenic therapies, poly (ADP-ribose) polymerase inhibitors, adoptive cell therapy, and oncolytic therapy, could be beneficial. Further efforts are merited to transfer these results to a broader clinical application.

Case Report: Niraparib-Related Pulmonary Embolism During the Treatment of BRCA Mutant Advanced Ovarian Cancer

Niraparib, an oral, potent, highly selective poly (ADP-ribose) polymerase (PARP) inhibitor, has promising clinical benefit for maintenance treatment of patients with ovarian cancer in partial response to platinum-based chemotherapy, especially in patients with BRCA mutation. In publicly available niraparib treatment-related adverse events, gastrointestinal disorders and hematological toxicities were most commonly reported with manageable safety profile. Herein, we first describe a severe and never-reported pulmonary embolism (PE) associated with the use of niraparib in a patient with BRCA mutation advanced high-grade serous ovarian cancer and received anticoagulant therapy after PE. There have been no reports of PE caused by the use of niraparib in patients with advanced high-grade serous ovarian cancer; knowledge of the occurrence of PE after the use of niraparib may assist other clinicians in managing this rare but potentially serious toxic effect.

Efficacy and Prognostic Factors for PARP Inhibitors in Patients With Ovarian Cancer

Background: The prognostic factors for efficacy of poly(ADP-ribose) polymerase (PARP) inhibitors in ovarian cancer remain unknown. The purpose of this study is to evaluate the efficacy of PARP inhibitors and to explore their prognostic factors in ovarian cancer. Methods: PubMed, Embase, and conference databases were searched for relevant prospective clinical trials. The primary outcomes included overall survival (OS), progression-free survival (PFS), and their prognostic factors. Secondary outcomes included PFS2, time to first subsequent therapy (TFST), time to second subsequent therapy (TSST), chemotherapy-free interval (CFI), and their prognostic factors. Hazard ratio (HR) with a 95% confidence interval (CI) was used as an effect measure. Results: PARP inhibitors significantly prolonged PFS in patients with ovarian cancer regardless of their BRCA and HRD status (HR = 0.44, 95% CI = 0.36-0.55). BRCA mutation, HRD-positive status, and sensitivity to platinum represented effective prognostic factors for PFS (Pinteraction < 0.01 and within-trial interaction HR < 1). Other clinicopathological factors did not predict the benefit of PFS (Pinteraction > 0.10). Moreover, PARP inhibitors significantly increased PFS2, TFST, TSST, and CFI, with significant BRCA-related differences. However, HRD-related differences could not be evaluated due to the lack of eligible studies. Furthermore, PARP inhibitors did not translate into prolonged OS, although there was a benefit associated with OS (HR = 0.84, 95% CI = 0.70-1.02). PARP inhibitors used as maintenance therapy after first or subsequent line therapy improved OS (HR = 0.77, 95% CI = 0.63-0.93). Conclusions: PARP inhibitors can significantly prolong PFS, PFS2, TFST, TSST, and CFI in ovarian cancer patients. BRCA mutation, HRD-positive status, and sensitivity to platinum are effective prognostic factors for the efficacy of PARP inhibitors. However, despite the PFS improvement, this does not translate into prolonged OS for patients.

Management and Treatment of Recurrent Epithelial Ovarian Cancer

Most women with advanced epithelial ovarian cancer will experience many episodes of recurrent disease with progressively shorter disease-free intervals. For women whose disease continues to respond to platinum-based drugs, the disease can often be controlled for 5 years or more. Enormous progress has been made in the management of this disease, and new targeted treatments such as antiangiogenic drugs, poly(adenosine diphosphate-ribose) polymerase inhibitors, and immune checkpoint inhibitors offer potential for improved survival. A variety of combination strategies are being evaluated to leverage these agents. The role of secondary cytoreduction remains a topic of active investigation.

Cost-Effectiveness of Niraparib and Olaparib as Maintenance Therapy for Patients with Platinum-Sensitive Recurrent Ovarian Cancer

BACKGROUND

The recent approval of olaparib and niraparib as maintenance therapy can significantly affect the management of ovarian cancer. Clinical benefits, however, come with trade-offs in adverse events and costs.

OBJECTIVE

To evaluate the cost-effectiveness of new ovarian cancer poly-ADP ribose polymerase (PARP) inhibitor therapies, olaparib and niraparib, as maintenance therapy for patients with platinum-sensitive recurrent ovarian cancer.

METHODS

A decision tree model was constructed to evaluate the costs and effectiveness of olaparib and niraparib compared with placebo from a U.S. health care sector perspective. Costs included drug costs and costs of disease monitoring and management of adverse events throughout the treatment course. Costs were estimated from RED BOOK, Medicare reimbursement rates, and the literature and reported in 2017 U.S. dollars. Clinical effectiveness was measured in progression-free survival (PFS) life-years based on clinical trial results (NCT00753545, NCT01874353, and NCT01847274). The incremental cost-effectiveness ratio (ICER) was computed by dividing the incremental cost by the incremental effectiveness.

RESULTS

At base case, niraparib was the more effective treatment option with slightly higher PFS, followed by olaparib. The ICERs for niraparib and olaparib compared with common baseline placebo were $235K and $287K per PFS life-year, respectively, with olaparib extended-dominated by niraparib. Both drugs were associated with lower ICERs in patients with a gBRCA mutation than in patients without a gBRCA mutation. One-way sensitivity analysis suggested that drug prices and PFS could affect ICERs significantly, but the ICERs remained above $100K per PFS life-year within the plausible ranges of all parameters. Probabilistic sensitivity analysis suggested that niraparib was associated with higher net benefits compared with placebo only when willingness-to-pay (WTP) values were above $210K per PFS life-year thresholds.

CONCLUSIONS

PARP inhibitors niraparib and olaparib will extend PFS in platinum-sensitive recurrent ovarian cancer patients but are also associated with high drug acquisition costs. The base case ICERs were around or above $250K per PFS life-year in this model. No formal cost-effectiveness WTP threshold for health technology assessment exists in the United States. At a reference WTP of $100K per PFS life-year, the PARP inhibitors may not be cost-effective options.

DISCLOSURES

This study was unfunded. The authors have nothing to disclose.

Rucaparib maintenance treatment for recurrent ovarian carcinoma after response to platinum therapy (ARIEL3): a randomised, double-blind, placebo-controlled, phase 3 trial

BACKGROUND

Rucaparib, a poly(ADP-ribose) polymerase inhibitor, has anticancer activity in recurrent ovarian carcinoma harbouring a BRCA mutation or high percentage of genome-wide loss of heterozygosity. In this trial we assessed rucaparib versus placebo after response to second-line or later platinum-based chemotherapy in patients with high-grade, recurrent, platinum-sensitive ovarian carcinoma.

METHODS

In this randomised, double-blind, placebo-controlled, phase 3 trial, we recruited patients from 87 hospitals and cancer centres across 11 countries. Eligible patients were aged 18 years or older, had a platinum-sensitive, high-grade serous or endometrioid ovarian, primary peritoneal, or fallopian tube carcinoma, had received at least two previous platinum-based chemotherapy regimens, had achieved complete or partial response to their last platinum-based regimen, had a cancer antigen 125 concentration of less than the upper limit of normal, had a performance status of 0-1, and had adequate organ function. Patients were ineligible if they had symptomatic or untreated central nervous system metastases, had received anticancer therapy 14 days or fewer before starting the study, or had received previous treatment with a poly(ADP-ribose) polymerase inhibitor. We randomly allocated patients 2:1 to receive oral rucaparib 600 mg twice daily or placebo in 28 day cycles using a computer-generated sequence (block size of six, stratified by homologous recombination repair gene mutation status, progression-free interval after the penultimate platinum-based regimen, and best response to the most recent platinum-based regimen). Patients, investigators, site staff, assessors, and the funder were masked to assignments. The primary outcome was investigator-assessed progression-free survival evaluated with use of an ordered step-down procedure for three nested cohorts: patients with BRCA mutations (carcinoma associated with deleterious germline or somatic BRCA mutations), patients with homologous recombination deficiencies (BRCA mutant or BRCA wild-type and high loss of heterozygosity), and the intention-to-treat population, assessed at screening and every 12 weeks thereafter. This trial is registered with ClinicalTrials.gov, number NCT01968213; enrolment is complete.

FINDINGS

Between April 7, 2014, and July 19, 2016, we randomly allocated 564 patients: 375 (66%) to rucaparib and 189 (34%) to placebo. Median progression-free survival in patients with a BRCA-mutant carcinoma was 16·6 months (95% CI 13·4-22·9; 130 [35%] patients) in the rucaparib group versus 5·4 months (3·4-6·7; 66 [35%] patients) in the placebo group (hazard ratio 0·23 [95% CI 0·16-0·34]; p<0·0001). In patients with a homologous recombination deficient carcinoma (236 [63%] vs 118 [62%]), it was 13·6 months (10·9-16·2) versus 5·4 months (5·1-5·6; 0·32 [0·24-0·42]; p<0·0001). In the intention-to-treat population, it was 10·8 months (8·3-11·4) versus 5·4 months (5·3-5·5; 0·36 [0·30-0·45]; p<0·0001). Treatment-emergent adverse events of grade 3 or higher in the safety population (372 [99%] patients in the rucaparib group vs 189 [100%] in the placebo group) were reported in 209 (56%) patients in the rucaparib group versus 28 (15%) in the placebo group, the most common of which were anaemia or decreased haemoglobin concentration (70 [19%] vs one [1%]) and increased alanine or aspartate aminotransferase concentration (39 [10%] vs none).

INTERPRETATION

Across all primary analysis groups, rucaparib significantly improved progression-free survival in patients with platinum-sensitive ovarian cancer who had achieved a response to platinum-based chemotherapy. ARIEL3 provides further evidence that use of a poly(ADP-ribose) polymerase inhibitor in the maintenance treatment setting versus placebo could be considered a new standard of care for women with platinum-sensitive ovarian cancer following a complete or partial response to second-line or later platinum-based chemotherapy.

FUNDING

Clovis Oncology.

Reducing excessive toxicity in ovarian cancer treatment: a personalized approach

The management of ovarian cancer is not only multifactorial, but also patient-specific. Different treatment modalities lead to varying levels of toxicity and individual patient responses, necessitating a personalized approach to each treatment plan. Surgical treatment along with first-line and salvage chemotherapies, are standard modalities but recent innovations in chemotherapy delivery and innovative therapy with mechanism of action are reviewed in this article. Extensive experience with standard chemotherapy has outlined algorithms for managing various toxicities. The focus of treatment may ultimately point towards palliative care and clinicians must be comfortable and well versed in addressing this important option. Overall, management of ovarian cancer requires a multi-faceted approach, keeping the patients’ overall health, curative goals and well-being at the forefront. It is nearly impossible to detail exact management plans for every possible toxicity for every patient; formulating personalized treatment plans should be based on evidence and clinician experience, all part of the art of medicine. The objective of this article is to highlight the most frequently encountered and most limiting toxicities of current standard therapies for epithelial ovarian cancer.

Phase II study of combination chemotherapy with etoposide and ifosfamide in patients with heavily pretreated recurrent or persistent epithelial ovarian cancer

The aim of this trial was to investigate the efficacy and toxicity of combination chemotherapy with etoposide and ifosfamide (ETI) in the management of heavily pretreated recurrent or persistent epithelial ovarian cancer (EOC). Patients with recurrent or persistent EOC who had measurable disease and at least two prior chemotherapy participating in this phase II trial were to receive etoposide at a dose of 100 mg/m(2)/day intravenously (IV) on days 1 to 3 in combination with ifosfamide 1 g/m(2)/day IV on days 1 to 5, every 21 days. Thirty-seven patients were treated; about 78% had previously received more than two separate regimens. The response rate (RR) was 18.9% and median duration of response was 7 months (range, 1-15). Treatment free interval prior to ETI (TFI) has significant correlation with RR rate (P=0.034). Patients (n=6) with TFI > or =6 months had 50% of RR, while patients (n=31) with TFI <6 months had 12.9%. Median survival was 9 months at a median follow-up of 9.2 months. Grade 3 or 4 toxicities included neutropenia in 20.1% of the 139 cycles of ETI, anemia in 7.2% and thrombocytopenia in 8.6%. The ETI produces relatively low toxicity and modest activity in heavily pretreated recurrent or persistent EOC. This is significant in patients with TFI > or =6 months.

A review of the current evidence for maintenance therapy in ovarian cancer

OBJECTIVES

Ovarian cancer (OC) typically is diagnosed at advanced stages, in which the primary goal of therapy is to prolong progression-free survival (PFS) and overall survival (OS). In recent years, maintenance therapy has been tested for this purpose in advanced OC (AOC). Literature on maintenance therapy in AOC was systematically reviewed to assess current knowledge regarding the impact of this therapeutic approach.

METHODS

A MEDLINE search was performed 2/2009 for articles published 1/2001-1/2009 pertaining to OC maintenance therapy guidelines, patterns, and outcomes. A second search used keywords specific to maintenance and included primary studies published in the last 10 years. Of 406 sources identified, 36 primary studies and 16 review articles were included in this systematic review. A third search used the keyword "consolidation" to find maintenance articles not identified through other searches; of 48 additional sources, 13 primary studies and 6 reviews were included. A fourth search of non-MEDLINE-indexed sources yielded 14 additional relevant publications from the same time period.

RESULTS

Among practice guidelines identified, only the National Comprehensive Cancer Network (NCCN) 2008 guidelines provide recommendations regarding maintenance therapy, assigning it a category 2B recommendation. No studies were identified that reported current treatment patterns or economic outcomes in maintenance therapy; quality of life data were reported in one study. A variety of agents have been tested for maintenance, with paclitaxel the most commonly evaluated. The Southwest Oncology Group-Gynecologic Oncology Group 178 trial has found that 12 cycles of paclitaxel extend PFS (by 7 months) compared to 3 months paclitaxel, but could not adequately evaluate OS.

CONCLUSIONS

Maintenance therapy may improve clinical outcomes in AOC, but additional research is needed to demonstrate an OS advantage. Future studies should investigate the long-term clinical benefit of maintenance treatment and its impact on resource utilization and health-related quality of life.

Hexamethylmelamine as consolidation treatment for patients with advanced epithelial ovarian cancer in complete response after first-line chemotherapy

The aim of this study was to assess the efficacy of consolidation therapy with hexamethylmelamine (HMM) in patients with advanced epithelial ovarian cancer (EOC). Patients treated at our hospital between January 1997 and November 2006 and in documented clinical complete response from advanced ovarian cancer following front-line platinum-based therapy were retrospectively analyzed. The patients treated with HMM were compared to the patients of matched counterpart without consolidation therapy. Of 102 patients enrolled, 49 were treated with HMM and 53 received no consolidation treatment. For patients with HMM and observed patients, the mean age were 54.6 and 55.6 yr; the distribution of stage was similar (P=0.977); the optimal surgery was performed in 36 (73.5%) and 44 (83%) (P=0.336); the recurrence rate were 27 (55.1%) and 33 (62.3%) (P=0.463); and the median progression-free survival were 38 months and 21 months for patients with HMM and observed patients (P=0.235). No treatment-related adverse events were reported during the follow-up period. Although this study failed to show the significant survival benefit of consolidation therapy with HMM in patients with advanced EOC, we consider that our study can contribute data to investigate the effectiveness of consolidation therapy in epithelial ovarian cancer.

Pilot Phase 2 Trial of 4 Months of Maintenance Pegylated Liposomal Doxorubicin in Patients with Advanced Ovarian Cancer after Complete Response to Platinum and Paclitaxel-Based Chemotherapy

BACKGROUND/AIMS

Stages III and IV ovarian and peritoneal cancer patients are commonly treated with combination chemotherapy after surgical debulking. This phase II trial investigated the use of pegylated liposomal doxorubicin as consolidation chemotherapy for these patients.

METHODS

Women with stage III or IV ovarian or primary peritoneal carcinoma demonstrating no clinical evidence of disease after primary therapy were eligible for enrollment. Patients received 4 cycles of 40 mg/m(2) IV of pegylated liposomal doxorubicin every 28 days.

RESULTS

Twelve patients were enrolled. There were 6 stage IIIC and 6 stage IV patients. Ten patients received 4 cycles. Two patients had dose limiting skin toxicity manifest as hand-foot syndrome and received only 3 cycles. Forty-six of a planned 48 cycles were administered. Median disease-free survival from registration is 10 months with a mean of 18 months. Median overall survival has not yet been reached. Four patients are disease-free, two have relapsed and six have died from disease progression.

CONCLUSION

Pegylated liposomal doxorubicin is a well-tolerated choice for consolidation chemotherapy in patients with ovarian or primary peritoneal carcinoma.

Consolidation therapy in ovarian cancer: where do we stand?

PURPOSE OF REVIEW

The goal of consolidation chemotherapy in ovarian cancer is to maximize the benefit of primary therapy and improve progression-free and overall survival. Consolidation has been tested with multiple treatment modalities including cytotoxic chemotherapy, radiation and biological therapies. A review of recently published clinical trials is presented.

RECENT FINDINGS

Consolidation therapy is not a new concept. More than 30 clinical trials utilizing consolidation therapy have been published in the last two decades. The natural history of many patients who participate in consolidation trials is often favorable, making the effect of consolidation treatments difficult to interpret. Small phase II studies have suggested improved outcomes compared with historical controls, but randomized trials have yet to show a distinct survival advantage with consolidation therapy.

SUMMARY

The role of consolidation therapy in ovarian cancer is evolving. Although it is recognized that ovarian cancer patients commonly suffer recurrences after initial response, it is not clear that current therapies alter this course. Future clinical designs should include appropriate control groups. Novel therapies should be studied in randomized controlled trials with sufficient power to detect relevant clinical differences, the most important being overall survival. Toxicity and ease of administration must be considered against the benefits of therapy.