Poly(ADP-ribose) polymerase inhibitors as maintenance treatment in patients with newly diagnosed advanced ovarian cancer: a meta-analysis

Prescribers and patients drive maintenance therapy patterns in a community oncology practice: National guidelines versus the real-world experience

Objective

Previous studies have shown that first-line (1L) maintenance therapy (MT) with poly(ADP-ribose) polymerase inhibitors and/or bevacizumab improves outcomes among patients with advanced ovarian cancer (OC); however, these treatments are underutilized. This study aimed to provide a real-world understanding of MTs among patients with advanced OC who received 1L platinum-based chemotherapy (PBC).

Methods

A retrospective chart review using iKnowMed electronic health records to identify patients aged ≥18 years with advanced OC who initiated 1L PBC between January 1, 2018-December 31, 2020. Following 1L PBC, patients could have received MT or active surveillance (AS). Kaplan-Meier methods were used to estimate time to treatment discontinuation (TTD), real-world progression-free survival (rwPFS), and overall survival (OS).

Results

Of the 600 chart-reviewed patients included, 239 (39.8 %) received MT and 315 (52.5 %) received AS. Patients who were <65 years of age, or those with higher-stage disease or those who had received neoadjuvant treatment, were more likely to initiate MT than AS. Genetic testing rates were low across both cohorts. Median (95 % confidence interval [CI]) TTD for the MT cohort was 13.6 months (11.0, 21.2). Median (95 % CI) rwPFS was 26.9 months (21.3, not reached) and 11.3 months (9.5, 13.0) for the 1L MT and AS cohorts, respectively (p < 0.0001). OS at 36 months was 82.4 % in the 1L MT cohort and 58.0 % in the 1L AS cohort.

Conclusions

This study reinforces clinical trial findings that 1L MT improves outcomes in patients with advanced OC; however, genetic testing rates and 1L MT remained low.

Clinical efficacy of plasmid encoding p62/SQSTM1 (Elenagen) in combination with gemcitabine in patients with platinum-resistant ovarian cancer: a randomized controlled trial

Background

The purpose of this trial is to evaluate the safety and efficacy of ELENAGEN, a novel anticancer therapeutic DNA plasmid encoding p62/SQSTM1 protein, as an adjuvant to chemotherapy with gemcitabine (GEM) in patients with advanced platinum-resistant ovarian cancer.

Methods

This open-label prospective randomized study with two arms. GEM (1000 mg/m2) on days 1 and 8 every 3 weeks was administered in both arms: in the Chemo arm (n = 20), GEM was the only treatment, and in the ELENAGEN arm (n = 20), GEM was supplemented with ELENAGEN (2.5 mg i.m. weekly). The primary endpoint was progression-free survival (PFS), and the secondary endpoint was safety. Antitumor activity was assessed by RECIST 1.1, and criteria safety was assessed according to NCI CTCAE version 5.0.

Results

According to the cutoff data, the median follow-up was 13.8 months. There were no serious adverse events related to ELENAGEN treatment. The median PFS was 2.8 and 7.2 months in the Chemo and ELENAGEN arms, respectively (p Log-Rank = 0.03). Notably, at the time of cutoff, 9 patients (45%) in the ELENAGEN arm did not progress, with the longest PFS recorded thus far being 24 months. Subgroup analysis of patients in both arms demonstrated high efficacy of ELENAGEN in patients with worse prognostic factors: high pretreatment levels of CA125 and progression after platinum-free interval <3 months.

Conclusions

The addition of ELENAGEN to gemcitabine is effective in patients with platinum-resistant ovarian cancer, including those with a worse prognosis.

Clinical trial registration

https://www.clinicaltrials.gov/study/NCT05979298, identifier NCT05979298, 2023-08-07.

Comparison of poly (ADP-ribose) polymerase inhibitors (PARPis) as maintenance therapy for newly-diagnosed and platinum-sensitive recurrent ovarian cancer with BRCA mutational status: a systematic review and network meta-analysis

BACKGROUND

Poly(adenosine diphosphate [ADP]-ribose) polymerase inhibitors (PARPi) treatment for ovarian cancer (OC) are ever-changing. This study aimed to compare the efficacy and overall safety of available PARPi as maintenance therapy for BRCA mutation status in patients with newly diagnosed and platinum-sensitive recurrent (PSR) OC patients.

RESEARCH DESIGN AND METHODS

Relevant RCTs were systematically retrieved from PubMed and Embase until 31 May 2022. Progression-free survival (PFS) and overall survival (OS) based on BRCA mutation status and adverse events (AEs) regardless of mutation were efficacy and safety endpoints.

RESULTS

In newly diagnosed BRCAm-OC patients, olaparib (HR: 0.33; 95% confidence interval [CI]: 0.25, 0.43) and other PARPis [niraparib (HR: 0.40; 95% CI: 0.29, 0.55), rucaparib (HR: 0.40; 95% CI: 0.21, 0.76) and veliparib (HR: 0.44; 95% CI: 0.28, 0.69)] had a statistically significant effect on PFS versus placebo. In BRCAm-PSROC patients, Olaparib exhibited significant benefit (HR: 0.69; 95% CI: 0.54, 0.88) for OS compared to other PARPis. In BRCAwt-PSR OC patients, Olaparib showed a favorable OS benefit than other PARPis (HR: 0.84; 95% CI: 0.57,1.22). Overall, safety profile of all PARPis was acceptable.

CONCLUSION

All PARPis showed significant benefit, with olaparib showing greater benefit in newly diagnosed and PSR OC women.

REGISTRATION

CRD42021288932.

Comparison of the Efficacy and Safety of PARP Inhibitors as a Monotherapy for Platinum-Sensitive Recurrent Ovarian Cancer: A Network Meta-Analysis

Background

The present COVID-19 pandemic has tended toward normality. To provide convenient, safe, and effective home treatment programs for patients with recurrent ovarian cancer (ROC), the clinical efficacy and safety of poly (ADP-ribose) polymerase inhibitor (PARPi) (including olaparib, niraparib, and rucaparib) monotherapy as a maintenance treatment for platinum-sensitive ROC were systematically evaluated.

Methods

Numerous electronic databases were systematically searched for randomized controlled trials (RCTs) of PARPi maintenance treatment for ROC that were published before June 2021. The primary endpoints were overall survival (OS) and progression-free survival (PFS), and the secondary endpoint was grade 3-4 adverse effects (AEs). After data extraction and the quality evaluation of the included studies, Bayesian network meta-analysis (NMA) was performed using R software. The ability of each treatment was ranked using the surface under the cumulative ranking (SUCRA) curve.

Results

The analysis included five studies and 1390 patients. The NMA results demonstrated that compared with the placebo, olaparib and niraparib exhibited significant benefits in the gBRCA-mutated population, and respectively reduced the risk of death by 31% (HR = 0.69, 95% CI: 0.53-0.90) and 34% (HR = 0.66, 95% CI: 0.44-0.99). Olaparib, niraparib, and rucaparib were all found to be very effective in prolonging PFS in patients with ROC. All three PARPi treatments increased the number of grade 3-4 AEs in patients with ROC as compared with the placebo.

Conclusions

Overall, olaparib and niraparib maintenance treatment can significantly prolong the OS of patients with gBRCA mutations. Furthermore, the three investigated PARPi monotherapy maintenance treatments can prolong PFS regardless of BRCA mutation status. Although the incidence of AEs in the treatment groups was found to be significantly higher than that in the placebo group, the patients in the treatment group tolerated the treatment. Home oral PARPi treatment can balance tumor treatment and pandemic prevention and control, and is the most convenient, safe, and effective home treatment method available against the background of the current COVID-19 pandemic.

Systematic Review Registration

https://inplasy.com/inplasy-2021-6-0033/.

Quantitative Analysis of the Efficacy of PARP Inhibitors as Maintenance Therapy in Recurrent Ovarian Cancer

Objective: This study aimed to establish a pharmacodynamic model and to screen reasonable covariates to quantitatively describe the efficacy of poly (ADP-ribose) polymerase inhibitors (PARPis) as maintenance treatment for recurrent ovarian cancer (ROC).

Methods: The log normal hazard function model was established by using progression-free survival (PFS) data of 1,169 patients from published randomized trials on FDA-approved PARP inhibitors (olaparib, niraparib, and rucaparib). Monte Carlo simulation was used to compare PFS values in different scenarios, such as monotherapy (administered alone) and combination therapy (PARPis combined with chemo- or target-therapies), different biomarker statuses, and different PARP inhibitors. PFS was also estimated.

Results: The study showed that the median PFS was 8.5 months with monotherapy and 16.0 months with combination therapy. The median PFS of patients with the BRCA mutation, BRCA wild-type, and HRD-positivity were 11.0, 7.5, and 9.0 months in monotherapy, respectively, and 23.0, 14.0 and 17.5 months, in combination therapy, respectively. In addition, the median PFS of olaparib, niraparib, and rucaparib monotherapy were about 9.5, 10.5, and 12.0 months, respectively, and about 19.0, 20.0, and 25 months, respectively, in combination therapy. The median PFS values in combination with cediranib, bevacizumab, and chemotherapy were approximately 17.0, 12.5 and 19.5 months, respectively.

Conclusion: PARPi combination therapy is more effective as maintenance treatment for ROC than monotherapy, and the efficacy of PARPis in combination with chemotherapy is higher than that of the combination with antiangiogenic drugs. We found that the PFS of BRCA wild-type was similar to that of HRD-positive patients, and there was no significant difference in PFS between olaparib, niraparib, and rucaparib, which provides necessary quantitative information for the clinical practice of PARPis in the treatment of ROC.

PARP inhibitors in breast and ovarian cancer with BRCA mutations: a meta-analysis of survival

Objective: To evaluate the efficacy of poly ADP ribose polymerase (PARP) inhibitors (PARPis) in breast and ovarian cancer with BRCA (BReast CAncer susceptibility gene) mutation (BRCAm).

Methods: We conducted a meta-analysis of randomized controlled, phase II or III trials by searching of electronic databases from inception to September 1, 2020. The efficacy of PARPis measured by hazard ratios (HRs) and 95% confidence intervals (95% CIs) for progression free survival (PFS) and overall survival (OS) of patients.

Results: By addition of PARPis to conventional therapy, breast or ovarian cancer patients carrying BRCAm significantly benefited PFS (breast cancer: HR 0.64, 95% CI=0.55-0.75, P<0.001; ovarian cancer: HR 0.33, 95% CI=0.27-0.42, P<0.001), but OS of patients did not increase significantly in these two cancer types (breast cancer: HR 0.87, 95% CI=0.76-1.01, P=0.065; ovarian cancer: HR 0.78, 95% CI=0.61-1.01, P=0.058). For ovarian cancer patients carrying BRCAm, the use of therapy with PARPis yielded longer PFS at the stage of newly diagnosed than the stage of recurrence (22.5 months vs 9.6 months).

Conclusion: PARPis were beneficial to all with BRCAm, but they were "most" beneficial to the ovarian cancer subset when administered early after diagnosis, rather than after recurrence.

Immune Modeling Analysis Reveals Immunologic Signatures Associated With Improved Outcomes in High Grade Serous Ovarian Cancer

Epithelial ovarian cancer (EOC) is the most lethal gynecologic malignancy worldwide, as patients are typically diagnosed at a late stage and eventually develop chemoresistant disease following front-line platinum-taxane based therapy. Only modest results have been achieved with PD-1 based immunotherapy in ovarian cancer patients, despite the fact that immunological responses are observed in EOC patients. Therefore, the goal of this present study was to identify novel immune response genes and cell subsets significantly associated with improved high grade serous ovarian cancer (HGSOC) patient prognosis. A transcriptomic-based immune modeling analysis was employed to determine levels of 8 immune cell subsets, 10 immune escape genes, and 22 co-inhibitory/co-stimulatory molecules in 26 HGSOC tumors. Multidimensional immune profiling analysis revealed CTLA-4, LAG-3, and Tregs as predictive for improved progression-free survival (PFS). Furthermore, the co-stimulatory receptor ICOS was also found to be significantly increased in patients with a longer PFS and positively correlated with levels of CTLA-4, PD-1, and infiltration of immune cell subsets. Both ICOS and LAG-3 were found to be significantly associated with improved overall survival in The Cancer Genome Atlas (TCGA) ovarian cancer cohort. Finally, PVRL2 was identified as the most highly expressed transcript in our analysis, with immunohistochemistry results confirming its overexpression in HGSOC samples compared to normal/benign. Results were corroborated by parallel analyses of TCGA data. Overall, this multidimensional immune modeling analysis uncovers important prognostic immune factors that improve our understanding of the unique immune microenvironment of ovarian cancer.

Comparative Efficacy and Safety of PARP Inhibitors as Maintenance Therapy in Platinum Sensitive Recurrent Ovarian Cancer: A Network Meta-Analysis

This meta-analysis investigated the comparative efficacy and safety of PARP inhibitor monotherapy as maintenance treatment in platinum sensitive recurrent ovarian cancer (ROC). Electronic databases were systematically searched for relevant RCTs. The primary endpoint was PFS. The results were stratified based on three categories: BRCA mutated patients, HRD patients, and overall population. The secondary outcome were discontinuations due to adverse events and grade 3 or 4 adverse events in maintenance phase. Five eligible RCTs were included in the network meta-analysis. For patients with BRCA mutated ovarian cancer, olaparib-throughout (HR = 0.21 with 95% CrI: 0.081-0.55), rucaparib (HR = 0.23 with 95% CrI: 0.16-0.34), olaparib (HR = 0.27 with 95% CrI: 0.20-0.35), and niraparib (HR = 0.26 with 95% CrI: 0.17-0.41) were all highly effective in comparison with placebo at improving PFS. For HRD patients, both rucaparib (HR = 0.32 with 95% CrI: 0.24-0.42) and niraparib (HR = 0.38 with 95% CrI: 0.24-0.60) were all highly effective in comparison with placebo at improving PFS. For the overall population, olaparib-throughout (HR = 0.51 with 95% CrI: 0.34-0.76), rucaparib (HR = 0.37 with 95% CrI: 0.30-0.45), olaparib (HR = 0.35 with 95% CrI: 0.25-0.49), and niraparib (HR = 0.38 with 95% CrI: 0.30-0.48) were all highly effective in comparison with placebo at improving PFS. Regarding grade 3 or 4 adverse events, the incidence of grade 3 or 4 toxicity reactions to rucaparib and niraparib were significantly higher than in the olaparib group. In terms of discontinuations due to adverse events, the treatment discontinuations were not significantly different between the three drugs. In summary, all the included maintenance treatment regimens are effective regardless of BRCA mutational status, and no statistically significant differences between rucaparib, niraparib and Olaparib in terms of PFS. In terms of safety profile, the three drugs present manageable adverse events. Clinicians should consider potential adverse events related to each of these interventions in clinical practice, and the adverse events are generally manageable.

Current Ovarian Cancer Maintenance Strategies and Promising New Developments

While ovarian cancer typically responds well to front line treatment, many patients will relapse within 5 years. Treatment options are less effective at each recurrence highlighting the need for novel maintenance therapies. PolyADP-ribose polymerase (PARP) inhibitors have recently gained approval in ovarian cancer maintenance. Niraparib was approved regardless of BRCA mutation status, however impact on overall survival is limited. Oliparib was approved for BRCA mutant and BRCA wildtype/homologous recombination deficient patients. This review will focus on current frontline ovarian cancer treatment as well molecularly based approaches to ovarian cancer management.

The Perfect Combination: Enhancing Patient Response to PD-1-Based Therapies in Epithelial Ovarian Cancer

Epithelial ovarian cancer (EOC) is the most lethal gynecologic malignancy, with an overall 5-year survival of only 47%. As the development of novel targeted therapies is drastically necessary in order to improve patient survival, current EOC clinical trials have heavily focused on immunotherapeutic approaches, centered upon programmed cell death 1 (PD-1) inhibitors. While PD-1 monotherapies have only exhibited modest responses for patients, it has been theorized that in order to enhance EOC patient response to immunotherapy, combinatorial regimens must be investigated. In this review, unique challenges to EOC PD-1 response will be discussed, along with a comprehensive description of both preclinical and clinical studies evaluating PD-1-based combinatorial therapies. Promising aspects of PD-1-based combinatorial approaches are highlighted, while also discussing specific preclinical and clinical areas of research that need to be addressed, in order to optimize EOC patient immunotherapy response.

PARP inhibitors as maintenance therapy in newly diagnosed advanced ovarian cancer: a meta-analysis

BACKGROUND

Up to 70% of patients with advanced ovarian cancer have a relapse after primary therapy. New agents and approaches are urgently needed to avoid or slow down this recurrence.

OBJECTIVES

To investigate the efficacy of PARP inhibitors (PARPis) as maintenance treatment in patients with newly diagnosed advanced ovarian cancer.

SEARCH STRATEGY

PubMed, MEDLINE, EMBASE, Cochrane Library and Web of Science databases.

SELECTION CRITERIA

All randomised clinical trials (RCTs) that compared PARPis with placebo as first-line maintenance therapy in ovarian cancer.

DATA COLLECTION AND ANALYSIS

Two reviewers extracted data. Pooled hazard ratio (HR) and risk ratio (RR) with 95% confidence interval (CI) were calculated.

MAIN RESULTS

PARPis were associated with significant improvement of progression-free survival (PFS) in advanced epithelial ovarian cancer (AeOC) (HR = 0.53, 95% CI 0.40-0.71; P < 0.0001). The benefit was not only in women with BRCA mutations (HR = 0.35, 95% CI 0.29-0.42; P < 0.00001) and homologous recombination deficiency (HRD) (HR = 0.43, 95% CI 0.32-0.60; P < 0.00001), but also in those with nonmutated BRCA (HR = 0.72, 95% CI 0.63-0.82; P < 0.00001) and even non-HRD (HR = 0.83, 95% CI 0.70-0.99; P = 0.04).

CONCLUSIONS

PARP inhibitors are effective as maintenance therapy among patients with newly diagnosed advanced ovarian cancer after platinum-based chemotherapy, regardless of BRCA mutation or HRD status.

TWEETABLE ABSTRACT

PARPis provide a significant PFS benefit as first-line maintenance therapy in patients with newly diagnosed advanced ovarian cancer.

The biomarker HE4 (WFDC2) promotes a pro-angiogenic and immunosuppressive tumor microenvironment via regulation of STAT3 target genes

Epithelial ovarian cancer (EOC) is a highly lethal gynecologic malignancy arising from the fallopian tubes that has a high rate of chemoresistant recurrence and low five-year survival rate. The ovarian cancer biomarker HE4 is known to promote proliferation, metastasis, chemoresistance, and suppression of cytotoxic lymphocytes. In this study, we sought to examine the effects of HE4 on signaling within diverse cell types that compose the tumor microenvironment. HE4 was found to activate STAT3 signaling and promote upregulation of the pro-angiogenic STAT3 target genes IL8 and HIF1A in immune cells, ovarian cancer cells, and endothelial cells. Moreover, HE4 promoted increases in tube formation in an in vitro model of angiogenesis, which was also dependent upon STAT3 signaling. Clinically, HE4 and IL8 levels positively correlated in ovarian cancer patient tissue. Furthermore, HE4 serum levels correlated with microvascular density in EOC tissue and inversely correlated with cytotoxic T cell infiltration, suggesting that HE4 may cause deregulated blood vessel formation and suppress proper T cell trafficking in tumors. Collectively, this study shows for the first time that HE4 has the ability to affect signaling events and gene expression in multiple cell types of the tumor microenvironment, which could contribute to angiogenesis and altered immunogenic responses in ovarian cancer.