Safety and management of niraparib monotherapy in ovarian cancer clinical trials

Tolerability of the niraparib individualized starting dose in the PRIMA/ENGOT-OV26/GOG-3012 trial of niraparib first-line maintenance therapy

PURPOSE

To explore safety and tolerability parameters for the niraparib individualized starting dose (ISD) in patients with newly diagnosed advanced ovarian cancer that responded to platinum-based chemotherapy who participated in the phase 3 PRIMA/ENGOT-OV26/GOG-3012 trial (NCT02655016).

METHODS

The PRIMA protocol was amended so newly enrolled patients received an ISD based on baseline body weight/platelet count. In this ad hoc analysis, the timing, duration, and resolution of the first occurrence of common any-grade hematologic (thrombocytopenia, anemia, neutropenia) and nonhematologic (nausea, asthenia/fatigue, constipation, insomnia, hypertension) treatment-emergent adverse events (TEAEs) were evaluated by treatment arm in the ISD safety population (data cutoff, November 17, 2021; median follow-up, 3.5 years).

RESULTS

Of 733 randomized patients, 255 were enrolled after the ISD protocol amendment and received ≥ 1 dose of study treatment (niraparib, 169; placebo, 86). In the niraparib arm, median times to first events were 22.0-35.0 days for hematologic TEAEs and 7.0-56.0 days for nonhematologic TEAEs. First events resolved in ≥ 89.8% of patients for hematologic TEAEs; for nonhematologic TEAEs, resolution rates ranged from 55.3% (insomnia) to 86.0% (nausea). Median durations of first hematologic TEAEs were ≤ 16.0 days, but for first nonhematologic TEAEs ranged from 18.0 days (nausea) to 134.0 days (insomnia).

CONCLUSION

The niraparib ISD was generally well tolerated and TEAEs were manageable. Common hematologic and nonhematologic TEAEs occurred early and first events of hematologic TEAEs had a short duration (≈ 2 weeks) and a high resolution rate. These findings support close monitoring immediately following niraparib initiation and may help inform patient expectations for niraparib safety.

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.

Tailored Treatment Strategies in First Line Therapy for Ovarian Cancer Patients: A Critical Review of the Literature

BACKGROUND

Ovarian cancer (OC) is a significant cause of cancer-related mortality in women globally, with a five-year survival rate of approximately 49%. Standard therapy involves cytoreductive surgery followed by chemotherapy. Its poor prognosis has driven interest in alternative therapies such as targeted molecular agents like bevacizumab and poly (ADP-ribose) polymerase inhibitors (PARPi).

MATERIALS AND METHODS

This review systematically searched PubMed from January 2018 to December 2023 for studies on PARPi in OC. Emphasis was on identifying relevant Phase III trials, extracting data on study design, patient demographics, and outcomes. Special focus was on assessing PARPi efficacy, safety, impact on quality of life, and ongoing trials, including those on Clinicaltrials.gov.

RESULTS

The efficacy of PARPi in first-line therapy for OC has been extensively studied. Trials like SOLO-1, PRIMA, and ATHENA-MONO have demonstrated significant improvements in progression-free survival (PFS) and overall survival (OS), particularly in patients with BRCA mutations. Additionally, the combination of PARPi with other agents like bevacizumab has shown promising results in extending PFS. However, PARPi treatment is associated with various adverse effects, including hematologic toxicities like anemia, thrombocytopenia, and neutropenia. While most adverse events are manageable, some patients may require dose adjustments or discontinuation of treatment. Importantly, PARPi maintenance therapy has not adversely affected health-related quality of life (HRQoL), with studies reporting similar HRQoL scores between PARPi-treated and placebo-treated patients.

CONCLUSIONS

PARPi offer effective treatment with manageable side effects, suitable even for medically fragile patients. Individualized dosing can optimize benefits while minimizing adverse events. Exploring diverse treatment approaches, particularly in patients with limited life expectancy or high disease burden, could improve outcomes. Ongoing research is investigating alternative therapies and combinations to broaden treatment options. Combining bevacizumab with PARPi may be justified for first-line and recurrent maintenance therapy. Regardless of mutational status, PARPi should be considered for maintenance therapy in newly diagnosed advanced OC. Platinum sensitivity remains crucial for treatment decisions and predicting survival outcomes.

Effects of niraparib dose reduction on short-term outcomes in ovarian cancer patients

OBJECTIVES

Despite the individualized starting dose for maintenance therapy in ovarian cancer, the niraparib dose reduction rate remains high. The aim of this study was to evaluate the impact of niraparib dose reduction on progression-free survival in newly diagnosed primary advanced ovarian cancer and recurrent ovarian cancer patients. We also aimed to compare the reduction rates and the safety of niraparib on primary and relapse groups, and identify which factors may predict dose reduction.

METHODS

Patients with primary or recurrent ovarian cancer in maintenance who received niraparib between 2019 and 2022 were retrospectively evaluated. Niraparib dosing was based on individualized starting dose of 300 or 200 mg/day. The impact of niraparib dose reductions was focused on patients treated with 200 or 100 mg in both groups. Reduction rates, adverse events and predictive factors of reduction were assessed in each study group. The primary endpoint was progression-free survival in primary and relapse groups; the secondary endpoints were the reduction rates, the safety and tolerability of niraparib in both groups.

RESULTS

Of 215 patients identified, 124 (57.7%) primary and 91 (42.3%) recurrent ovarian cancer patients were included. The majority of patients started niraparib at 200 mg/day (92.7% primary and 80.2% relapse group); dose reductions from 300 or 200 mg/day to 200 or 100 mg/day occurred more frequently within cycles 1-3 (67% primary and 45% relapse group, p=0.001). Grade≥3 adverse events were lower in the relapse group (54.8% primary and 35.1% relapse, p=0.001). In both groups, dose modifications over the treatment did not significantly impair median progression-free survival. Univariate and multivariate analysis demonstrated that weight and platinum-doublets were possible risk factors for dose reduction.

CONCLUSIONS

Niraparib dose reduction occurs in almost half of patients within cycles 1-3, although it is significantly more common in the first-line setting. Survival outcomes seem not to be impaired by dose reduction.

Beyond monotherapy: An era ushering in combinations of PARP inhibitors with immune checkpoint inhibitors for solid tumors

The introduction of PARP inhibitors (PARPis) and immune checkpoint inhibitors (ICIs) has marked a significant shift in the treatment landscape for solid tumors. Emerging preclinical evidence and initial clinical trials have indicated that the synergistic application of PARPis and ICIs may enhance treatment efficacy and potentially improve long-term patient outcomes. Nonetheless, how to identify specific tumor types and molecular subgroups most likely to benefit from this combination remains an area of ongoing research. This review thoroughly examines current studies on the co-administration of PARPis and ICIs across various solid tumors. It explores the underlying mechanisms of action, evaluates clinical efficacy, identifies potential responder populations, and delineates common adverse events alongside strategic management approaches. The aim is to offer a detailed understanding of this combination therapy, potentially guiding future therapeutic strategies for solid tumors.

Real world data of niraparib in platinum sensitive relapsed ovarian cancer: A multicenter experience of the MITO group

OBJECTIVE

PARP (poly adenosine diphosphate [ADP]-ribose polymerase) inhibitors are approved as maintenance therapy in platinum sensitive ovarian cancer (OC), in first line and in the recurrent setting, regardless of BRCA mutational status. Real-world data after the introduction of these agents are needed to evaluate whether the benefit observed in phase III randomized clinical trials can be translated into clinical practice. The aim of our study was to provide real-life data on efficacy and safety of niraparib administered as maintenance in platinum sensitive relapsed OC patients (PSROC).

METHODS

This retrospective/prospective observational study included relapsed OC patients that received niraparib as maintenance, at the time of platinum sensitive recurrence within the Italian expanded-access program. Clinical data at the time of diagnosis and at the time of recurrence were collected and analyzed. Median progression free survival (PFS) and overall survival (OS) were calculated as the time from start of niraparib treatment to subsequent radiologically confirmed relapse and death or last contact, respectively.

RESULTS

Among 304 eligible patients, 260 (85%) had BRCA wild-type tumor and 36. (11.9%) were BRCA mutated. Median PFS was 9.1 months (95% CI: 6.9-11.2) and 10.3 months (95% CI: 7.0-13.5) in the BRCAwt and BRCAmut cohorts, respectively. Furthermore, median OS was 41.7 months (95% CI: 31.6-41.9) and 34.6 months (95% CI: N.E.) in the BRCAwt and BRCAmut cohorts, respectively.

CONCLUSION

Data from this large real-life dataset suggested that maintenance with niraparib in the real-life setting of platinum sensitive OC recurrence is effective and well tolerated.

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.

Efficacy and Safety of Niraparib as First-Line Maintenance Treatment for Patients with Advanced Ovarian Cancer: Real-World Data from a Multicenter Study in China

BACKGROUND

Poly (ADP-ribose) polymerase (PARP) inhibitors are a new maintenance therapy option for patients with ovarian cancer (OC).

OBJECTIVE

To evaluate the efficacy and influencing factors of the novel PARP inhibitor niraparib for maintenance treatment of Chinese patients with advanced OC.

PATIENTS AND METHODS

In this retrospective multicenter real-world study patients with advanced OC from 15 hospitals throughout China were enrolled. The primary endpoint was progression-free survival (PFS) and the secondary endpoints included the time to treatment discontinuation and safety. Least Absolute Shrinkage and Selection Operator (LASSO) regression was used to identify possible risk factors for PFS, after which a prediction model was established to evaluate the likelihood of achieving an 18-month PFS. The relationship between the dose of niraparib and PFS was also evaluated.

RESULTS

The PFS rates of 199 patients at 6, 12, 18, 24, and 30 months were 87.4%, 75.9%, 63.6%, 56.1%, and 51.8%, respectively. LASSO regression model revealed that only age < 65 years (P = 0.011), BRCA mutations (P < 0.001), and R0 status after cytoreductive surgery (P = 0.01) were significant factors associated with prolonged PFS times. Based on the LASSO logistic regression analysis, a clinical prediction formula was developed: - 2.412 + 1.396Age≥65yr + 2.374BRCAwt + 1.387R1 + 0.793Interval≥12w + 0.178BMI>24kg/m2 which yielded a cut-off value of 0.091, an area under the curve (AUC) of 0.839 (0.763-0.916), a sensitivity of 94.3%, and an accuracy of 78.5%. A nomogram was then built to visualize the results. The major treatment-emergent adverse events of ≥ grade 3 included a platelet count decrease (19.1%), white blood cell count decrease (15.1%), neutrophil count decrease (13.1%), and anemia (18.6%). The 18-month PFS rates in patients treated with 200 mg niraparib were somewhat higher than in patients treated with 100 mg after 3-months of therapy.

CONCLUSIONS

For Chinese OC patients, niraparib, particularly at a 200 mg individual starting dose, was an effective therapy with easily manageable safety.