Utilization of Poly(ADP-Ribose) Polymerase Inhibitors in Ovarian Cancer: A Retrospective Cohort Study of US Healthcare Claims Data

Characteristics and real-world outcomes of patients with epithelial ovarian cancer who received niraparib plus bevacizumab first-line maintenance therapy in the COMB1NE study

OBJECTIVE

In the phase 2 OVARIO trial (NCT03326193) investigating niraparib-bevacizumab first-line maintenance, median progression-free survival was 14.2 months (95% confidence interval (CI) 8.6 to 16.8) for patients with homologous recombination (HR)-proficient (HRp) epithelial ovarian cancer, and 12.1 months (95% CI8.0-not evaluated) for patients with undefined HR status. However, real-world data are limited for patients who receive niraparib-bevacizumab first-line maintenance therapy. The COMB1NE study describes real-world clinical outcomes (time to treatment discontinuation; time to next treatment) in patients with epithelial ovarian cancer who received niraparib-bevacizumab first-line maintenance, regardless of first-line bevacizumab use.

METHODS

This real-world, retrospective study used a US nationwide electronic health record-derived deidentified database. Eligible patients were 18 years or older at initial epithelial ovarian cancer diagnosis and initiated niraparib-bevacizumab first-line maintenance (January 1, 2017-September 2, 2022) following first-line treatment. The index date was the start of first-line maintenance. Patients were followed until death, last clinical activity, or end of study, whichever occurred first. Time to treatment discontinuation and time to next treatment, a proxy for real-world progression-free survival, were estimated using the Kaplan-Meier method.

RESULTS

Among 59 included patients, the median age was 67 years (interquartile range (IQR) 61-76), and 81.4% had stage III/IV epithelial ovarian cancer at diagnosis. Overall, 83.1% of patients had BRCA wild-type with either HRp or HR status unknown disease. Median time to treatment discontinuation of first-line maintenance was 11.8 months (95% CI 8.7 to 13.5). Median time to next treatment was 14.1 months (95% CI 11.3 to 16.6). At 6 months after index, 77.9% of patients had not initiated second-line treatment; at 12 months, 61.3% had not.

CONCLUSION

In this real-world study of patients receiving niraparib-bevacizumab first-line maintenance, the majority of whom had HRp/HR status unknown, the median time to next treatment was consistent with observed progression-free survival in patients with similar HR status in the OVARIO study.

Niraparib as maintenance therapy in Japan: a retrospective observational study using a Japanese claims database

OBJECTIVE

Epithelial ovarian cancer (EOC) is the leading cause of female mortality in gynecologic malignancies, with a rising incidence in Japan. This study aimed to validate the treatment patterns and safety of niraparib as maintenance therapy for EOC following initial chemotherapy in clinical practice in Japan.

METHODS

Leveraging claims data between April 2008 and December 2022, this descriptive study comprised EOC-diagnosed patients receiving initial platinum-based chemotherapy, debulking surgery, and niraparib as maintenance therapy. Patient characteristics, prescription status, transfusion details, and laboratory data were assessed and reported as summary statistics and frequencies.

RESULTS

Among 291 patients, the median age was 64.0 years and 94.5% received a 200-mg daily dose of niraparib. At week 12, 78.7% (229/291) continued niraparib treatment, 21.3% (62/291) discontinued, and 52.2% (152/291) required treatment interruptions. Of the 62 patients who discontinued treatment, 27 patients initiated subsequent EOC treatment within 12 weeks following niraparib discontinuation. Blood transfusions were needed in 10.3% (30/291), and of 55 patients with available laboratory data, 61.8% (34/55) had decreased platelet count <100,000/µL, 25.5% (14/55) had decreased hemoglobin level <8 g/dL, and 22.7% (5/22) had decreased neutrophil count <1,000/µL, meeting the criteria for treatment interruption. Among those with thrombocytopenia, 88.2% (30/34) were able to either resume or continue treatment.

CONCLUSION

Niraparib demonstrated favorable tolerability in Japanese patients with advanced EOC, with effective management of thrombocytopenia through dose adjustments and supportive care, supporting its viability as post-chemotherapy maintenance therapy.

Comparison of Adverse Events Between PARP Inhibitors in Patients with Epithelial Ovarian Cancer: A Nationwide Propensity Score Matched Cohort Study

BACKGROUND

Despite improvement in progression-free survival (PFS) with poly (ADP-ribose) polymerase (PARP) inhibitors (PARPi) as maintenance treatment for patients with epithelial ovarian cancer (EOC), a comparative analysis of clinical events of interest (CEIs) of different PARPi is scarce.

OBJECTIVE

This study aimed to compare the safety of different PARPi in patients with EOC.

PATIENTS AND METHODS

Through analyzing the Korean National Health Insurance Service from January 2009 to January 2022, this study involved BRCA-mutated, platinum-sensitive patients with EOC treated with olaparib (tablet), niraparib, and olaparib (capsule) as first-line or second-line maintenance treatment. CEIs were identified using International Statistical Classification of Diseases (ICD) 9/10 codes, with additional outcomes being dose modification and persistence.

RESULTS

In the first-line maintenance treatment [118 niraparib, 104 olaparib (tablet) patients], no significant differences were noted in CEIs, dose reduction, or 6-month discontinuation rate. For second-line maintenance treatment [303 niraparib, 126 olaparib (tablet), and 675 olaparib (capsule) patients], niraparib was associated with a higher risk of hematologic CEIs, particularly anemia, compared with olaparib (tablet) (0.51 [0.26-0.98] and 0.09 [0.01-0.74], respectively), and higher rate of discontinuation rate at 6 months. Of note, patients over 60 years old showed an increased risk of CEIs with niraparib, as indicated by the hazard ratio divergence in restricted cubic spline plots.

CONCLUSIONS

No differences were observed among the PARPi during first-line maintenance treatment. However, in the second-line maintenance treatment, significant differences were observed in the risk of experiencing CEIs, dose alteration possibilities, and discontinuation of PARPi between niraparib and olaparib (tablets). Moreover, our findings suggest that an age of 60 years may be a critical factor in selecting PARPi to reduce CEI incidence.

PARP Inhibitors: Strategic Use and Optimal Management in Ovarian Cancer

Poly (ADP-ribose) polymerase (PARP) inhibitors have become an established part of the anticancer armamentarium. Discovered in the 1980s, PARP inhibitors (PARPis) were initially developed to exploit the presence of BRCA mutations, which disrupt the homologous recombination repair of deoxyribonucleic acid (DNA) via synthetic lethality, an intrinsic vulnerability caused by the cell's dependence on other DNA repair mechanisms for which PARP is an essential contributor. PARPi use expanded with the demonstration of clinical benefit when other mechanisms of high-fidelity DNA damage response were present in cancer cells called homologous repair deficiency (HRD). Recently, new data have resulted in the voluntary withdrawal of later-line treatment indications for all the available PARPis used in ovarian cancer because of a negative impact on overall survival (OS). PARPi switch maintenance to consolidate a response to platinum-based therapy is recommended for earlier treatment lines to have the greatest impact on the chance of cure and length of survival. This article reviews the clinical utility of PARPis and how to integrate them into best practices.

Comparison of survival outcomes between olaparib and niraparib maintenance therapy in BRCA-mutated, newly diagnosed advanced ovarian cancer

INTRODUCTION

This multicenter retrospective cohort study aimed to compare survival outcomes and adverse events between maintenance therapy with two poly (ADP-ribose) polymerase (PARP) inhibitors, olaparib and niraparib, in patients with BRCA-mutated, newly diagnosed advanced epithelial ovarian cancer (EOC) who responded to platinum-based chemotherapy.

METHODS

We enrolled stage III-IV EOC patients with germline and/or somatic BRCA1/2 mutations that had received maintenance therapy with olaparib or niraparib. A 3:1 propensity score matching was conducted using two variables: residual disease size and the presence of germline variants. The primary outcome was progression-free survival (PFS), and the secondary outcomes were time to first subsequent therapy (TFST), overall survival (OS), and treatment-emergent adverse events (TEAEs).

RESULTS

In the propensity score-matched analysis, 80 patients who received olaparib and 31 patients who received niraparib were matched (3:1). In the propensity score-matched cohort, median PFS with olaparib vs. niraparib was not reached vs 31.5 months (HR, 1.08; 95% CI, 0.47-2.52; p = 0.854). The median TFST was not reached vs 31.8 months (HR, 1.20; 95% CI, 0.51-2.81; p = 0.682), and neither olaparib nor niraparib reached the median OS (HR, 0.42; 95% CI, 0.01-17.61; p = 0.649). In terms of the incidence rates of any-grade hematologic or non-hematologic TEAEs, higher rates of thrombocytopenia (p = 0.021) and neutropenia (p = 0.011) were observed in the niraparib group.

CONCLUSION

Advanced EOC patients with BRCA1/2 mutations exhibited no significant difference in OS between olaparib and niraparib, indicating the need to consider individualized strategies for selecting PARP inhibitors based on adverse event profiles.

Health care services utilization in patients with ovarian cancer receiving PARP inhibitor maintenance treatment in a US community oncology setting

OBJECTIVES

The objective of this study was to describe healthcare resource use (HCRU) in addition to treatment patterns and discontinuations, in patients with ovarian cancer (OC) initiating PARP inhibitor (PARPi) maintenance treatment in a US community oncology setting.

METHODS

This was a retrospective study of patients with OC initiating PARPi monotherapy maintenance during 01/01/2017 to 06/30/2019 (followed until 12/31/2019). Patients aged ≥18 years at first diagnosis of OC with ≥2 visits within The US Oncology Network were included. Structured and chart review data as well as claims data were used to describe treatment patterns and HCRU.

RESULTS

Of the 162 charts reviewed, the median age of patients was 66 years and 80% had stage III or IV disease at diagnosis. In the niraparib, rucaparib and olaparib groups, proportions of patients experiencing dose interruptions were 51%, 50%, and 28%, and discontinuations due to toxicity were 37%, 17% and 15%, respectively. Within the first 6 months, mean numbers of total claims were 43.5, 56.4, and 36.0 in the niraparib, rucaparib, and olaparib groups, and laboratory claims were 13.9, 19.4, and 15.6, respectively. Proportions of patients with hospitalizations (niraparib 40%, rucaparib 32%, olaparib 19%; p = 0.03), also differed as did emergency department visits (niraparib 37%, rucaparib 23%, olaparib 16%; p = 0.02).

CONCLUSION

Despite patients initiating niraparib having higher rates of dose management events and toxicity-related discontinuations, outpatient and laboratory utilization were similar across all three PARPi. Adequate monitoring of these medications, with differing toxicities, should be emphasized to potentially decrease dose reductions and toxicities.

PARP Inhibitors in Ovarian Cancer: A Review

Poly(ADP-ribose) polymerase (PARP) inhibitors (PARPis) have transformed the ovarian cancer (OC) treatment landscape. This narrative review provides a comprehensive overview of data for the PARPis olaparib, niraparib, and rucaparib in patients with OC and discusses their role in disease management, with a focus on the use of PARPis as maintenance therapy in the United States (US). Olaparib was the first PARPi to be approved as first-line maintenance monotherapy in the US, with maintenance niraparib subsequently approved in the first-line setting. Data also support the efficacy of rucaparib as first-line maintenance monotherapy. PARPi maintenance combination therapy (olaparib plus bevacizumab) also provides benefit in patients with newly diagnosed advanced OC whose tumors tested positive for homologous recombination deficiency (HRD). Biomarker testing is critical in the newly diagnosed setting to identify patients most likely to benefit from PARPi maintenance therapy and guide treatment decisions. Clinical trial data support the use of PARPis (olaparib, niraparib, rucaparib) as second-line or later maintenance therapy in patients with platinum-sensitive relapsed OC. Although distinct differences in tolerability profile were observed between PARPis, they were generally well tolerated, with the majority of adverse events managed by dose modification. PARPis had no detrimental effect on patients' health-related quality of life. Real-world data support the use of PARPis in OC, although some differences between PARPis are apparent. Data from trials investigating novel combination strategies, such as PARPis plus immune checkpoint inhibitors, are awaited with interest; the optimal sequencing of novel therapies in OC remains to be established.

Managing Adverse Effects Associated With Poly (ADP-ribose) Polymerase Inhibitors in Ovarian Cancer: A Synthesis of Clinical Trial and Real-World Data

The use of poly (ADP-ribose) polymerase (PARP) inhibitor therapy is standard care in the management of patients with various malignancies including ovarian, breast, prostate, and pancreatic cancers. PARP inhibitors have been approved in different settings for patients with specific hereditary pathogenic variants, most notably homologous recombination repair pathways such as BRCA1 and BRCA2 genes. The vast experience with PARP inhibitors (olaparib, niraparib, rucaparib) has been in the management of epithelial ovarian cancer. There have not been any head-to-head comparisons of PARP inhibitors in randomized trials, and we can only perform cross-comparison on the basis of the reported literature. The three approved PARP inhibitors share several common adverse effects because of a class effect including nausea, fatigue, and anemia, but there are notable differences likely because of variations in their poly-pharmacology and off-target effects. Finally, patients included in clinical trials are often younger with a good performance status and less comorbidities than the real-world population, and hence, the potential benefits and adverse effects may not be superimposable. In this review, we describe these differences and discuss strategies to mitigate and manage adverse side effects effectively.

Real-world safety and effectiveness of maintenance niraparib for platinum-sensitive recurrent ovarian cancer: A GEICO retrospective observational study within the Spanish expanded-access programme

AIM

To describe patient characteristics, effectiveness and safety in a real-world population treated with niraparib in the Spanish expanded-access programme.

PATIENTS AND METHODS

This retrospective observational study included women with platinum-sensitive recurrent high-grade serous ovarian cancer who received maintenance niraparib within the Spanish niraparib expanded-access programme. Eligible patients had received ≥2 previous lines of platinum-containing therapy, remained platinum-sensitive after the penultimate line of platinum and had responded to the most recent platinum-containing therapy. Niraparib dosing was at the treating physician's discretion (300 mg/day fixed starting dose or individualised starting dose [ISD] according to baseline body weight and platelet count). Safety, impact of dose adjustments, patient characteristics and effectiveness were analysed using data extracted from medical records.

RESULTS

Among 316 eligible patients, 80% had BRCA wild-type tumours and 66% received an ISD. Median niraparib duration was 7.8 months. The most common adverse events typically occurred within 3 months of starting niraparib. Median progression-free survival was 8.6 (95% confidence interval [CI] 7.6-10.0) months. One- and 2-year overall survival rates were 86% (95% CI 81-89%) and 65% (95% CI 59-70%), respectively. Dose interruptions, dose reductions, haematological toxicities and asthenia/fatigue were less common with ISD than fixed starting dose niraparib, but progression-free survival was similar irrespective of dosing strategy. Subsequent therapy included platinum in 71% of patients who received further treatment.

CONCLUSION

Outcomes in this large real-world dataset of niraparib-treated patients are consistent with phase III trials, providing reassuring evidence of the tolerability and activity of niraparib maintenance therapy for platinum-sensitive recurrent ovarian cancer.

CLINICALTRIALS

GOV REGISTRATION

NCT04546373.

Maintenance therapy for newly diagnosed epithelial ovarian cancer- a review

Epithelial ovarian cancer (EOC) is the most lethal gynaecological cancer among women worldwide, with the 5-year survival rate ranging between 30 and 40%. Due to the asymptomatic nature of the condition, it is more likely to be diagnosed at an advanced stage, requiring an aggressive therapeutic approach. Cytoreductive surgery (CRS) along with systemic chemotherapy with paclitaxel and carboplatin has been the mainstay of the treatment in the frontline management of EOC. In recent years, neo-adjuvant chemotherapy, followed by interval CRS has become an important strategy for the management of advanced EOC. Due to the high rate of recurrence, the oncology community has begun to shift its focus to molecular-targeted agents and maintenance therapy in the frontline settings. The rationale for maintenance therapy is to delay the progression or relapse of the disease, as long as possible after first-line treatment, irrespective of the amount of residual disease. Tumours with homologous recombination deficiency (HRD) including BReast CAncer gene (BRCA) mutations are found to be sensitive to polyadenosine diphosphate-ribose polymerase (PARP) inhibitors and understanding of HRD status has become important in the frontline setting. PARP inhibitors are reported to provide a significant improvement in progression-free survival and have an acceptable safety profile. PARP inhibitors have also been found to act regardless of BRCA status. Recently, PARP inhibitors as maintenance therapy in the frontline settings showed encouraging results in EOC; however, the results from further trials and survival data from ongoing trials are awaited for understanding the role of this pathway in treatment of EOC. This review discusses an overview of maintenance strategies in newly diagnosed EOC along with considerations for maintenance therapy in EOC with a focus on PARP inhibitors.

Adverse Event Profiles of PARP Inhibitors: Analysis of Spontaneous Reports Submitted to FAERS

Background: Several poly ADP ribose polymerase inhibitors (PARPis) are currently approved for the treatment of a variety of cancers. The safety profile of PARPis has not yet been systemically analyzed in the real world. We conducted this pharmacovigilance analysis using the US FDA's Adverse Event Reporting System (FAERS) database to explore the difference in adverse events (AEs) among PARPis. Methods: FAERS data (December 2014 to October 2021) were searched for reports of all FDA-approved PARPis across all indications. We used the standardized MedDRA query (SMQ) generalized search AEs on the preferred term (PT) level based on case reports. After filtering duplicate reports, disproportionality analysis was used to detect safety signals by calculating reporting odds ratios (ROR). Reports were considered statistically significant if the 95% confidence interval did not contain the null value. Results: Within the standardized MedDRA queries, significant safety signals were found, including those for olaparib [blood premalignant disorders (ROR = 17.06)], rucaparib [taste and smell disorders (ROR = 9.17)], niraparib [hematopoietic throbocytopenia (ROR = 28.2)], and talazoparib [hematopoietic erythropenia (ROR = 9.38)]. For AEs on the PT level, we found several significant signals, including platelet count decreased with niraparib (ROR = 52.78); red blood cell count decreased with niraparib (ROR = 70.47) and rucaparib (ROR = 15.09); myelodysplastic syndrome with olaparib (ROR = 35.47); acute myeloid leukaemia with olaparib (ROR = 25.14); blood pressure fluctuation with niraparib (ROR = 20.54); lymphangioleiomyomatosis with niraparib (ROR = 471.20); photosensitivity reaction with niraparib (ROR = 21.77) and rucaparib (ROR = 18.92); renal impairment with rucaparib (ROR = 33.32); and interstitial lung disease with Olaparib (ROR = 11.31). All the detected safety signals were confirmed using signals of disproportionality reporting methods. Conclusion: PARPis differed in their safety profile reports. The analysis of the FAERS database revealed significant safety signals that matched previously published case reports, including serious gastrointestinal, blood and lymphatic system, cardiovascular and respiratory complications, which require individualized drug administration according to patients' conditions.