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

INTRODUCTION: We aimed to characterize real-world utilization of poly(ADP-ribose) polymerase (PARP) inhibitors (PARPi) in women with ovarian cancer (OC). METHODS: This retrospective observational study of claims data from US MarketScan® Commercial/Medicare Supplemental databases included women with OC initiating olaparib, niraparib, or rucaparib from January 1, 2017, to May 31, 2019. Patients were observed from first outpatient prescription until at least 30 days' follow-up. Clinical events of interest (CEIs), based on adverse reactions in PARPi prescribing information, were identified from claims using ICD-9/10 codes. Other outcomes included dose modification, persistence, adherence, healthcare resource utilization (HCRU), and cost. RESULTS: Overall, 303, 348, and 162 women with OC received olaparib, niraparib, and rucaparib, respectively. During follow-up, risk of any CEI was higher with niraparib versus olaparib (odds ratio 3.36 [95% confidence interval 2.00-5.65]) and niraparib versus rucaparib (2.09 [1.10-3.95]), with no significant difference between rucaparib and olaparib (1.61 [0.93-2.79]). PARPi dose decreases were observed in 21.1%, 35.1%, and 30.2% of olaparib-, niraparib-, and rucaparib-treated patients, respectively. Persistence (no treatment gaps of more than 90 days) was significantly higher (P < 0.05) with olaparib (62.2%) versus niraparib (35.9%) and rucaparib (48.7%); adherence (medication possession ratio, MPR ≥ 80%) was 80.2% versus 38.6% and 63.2%, respectively (P < 0.001). Inpatient admissions and outpatient service use were higher with niraparib and rucaparib versus olaparib, reflected in mean (± standard deviation) total medical costs (excluding pharmacy) of $5393 ± 8828 for olaparib, $7732 ± 14,054 for niraparib, and $6868 ± 7929 for rucaparib. CONCLUSION: Differences between the licensed PARPi were observed in the risk of experiencing a CEI, likelihood of dose modifications, ability to receive continuous PARPi therapy, HCRU, and costs.

The preferences of women with ovarian cancer for oral versus intravenous recurrence regimens.

OBJECTIVE: To assess preferences of women with ovarian cancer regarding features of available anti-cancer regimens for platinum-resistant, biomarker-positive disease, with an emphasis on oral PARP inhibitor and standard intravenous (IV) chemotherapy regimens. METHODS: A discrete-choice-experiment preferences survey was designed, tested, and administered to women with ovarian cancer, with 11 pairs of treatment profiles defined using seven attributes (levels/ranges): regimen (oral daily, IV weekly, IV monthly); probability of progression-free (PFS) at 6 months (40%-60%); probability of PFS at 2 years (10%-20%); nausea (none, moderate); peripheral neuropathy (none, mild, moderate); memory problems (none, mild); and total out-of-pocket cost ($0 to $10,000). RESULTS: Of 123 participants, 38% had experienced recurrence, 25% were currently receiving chemotherapy, and 18% were currently taking a PARP inhibitor. Given attributes and levels, the relative importance weights (sum 100) were: 2-year PFS, 28; cost, 27; 6-month PFS, 19; neuropathy,14; memory problems, nausea, and regimen, all ≤5. To accept moderate neuropathy, participants required a 49% (versus 40%) chance of PFS at 6 months or 14% (versus 10%) chance at 2 years. Given a 3-way choice where PFS and cost were equal, 49% preferred a monthly IV regimen causing mild memory problems, 47% preferred an oral regimen causing moderate nausea, and 4% preferred a weekly IV regimen causing mild memory and mild neuropathy. CONCLUSIONS: These findings challenge the assumption that oral anti-cancer therapies are universally preferred by patients and demonstrate that there is no "one size fits all" regimen that is preferable to women with ovarian cancer when considering recurrence treatment regimens.

Cost-effectiveness of olaparib as a maintenance treatment for women with newly diagnosed advanced ovarian cancer and BRCA1/2 mutations in the United States.

OBJECTIVE: This study evaluated the cost-effectiveness of olaparib monotherapy in the first-line maintenance setting vs. surveillance in women with newly diagnosed advanced ovarian cancer and a BRCA1/2 mutation from a US third-party payer perspective. METHODS: A three-state (progression free, progressed disease, and death) partitioned survival model over a 50-year lifetime horizon was developed. Piecewise models were applied to data from the phase III trial SOLO1 to extrapolate survival outcomes. Health state utilities and adverse event disutilities were obtained from literature and SOLO1. Treatment costs, adverse event costs, and medical costs associated with health states were obtained from publicly available databases, SOLO1, and real-world data. Time on treatment was estimated using the data from SOLO1. Incremental costs per quality-adjusted life year (QALY) and life year (LY) gained were estimated. One-way deterministic and probabilistic sensitivity analyses were conducted. RESULTS: Over a lifetime horizon, olaparib was associated with an additional 3.63 LYs and 2.93 QALYs, and an incremental total cost of $152,545 vs. surveillance. Incremental cost per LY gained and per QALY gained for olaparib were $42,032 and $51,986, respectively. The incremental cost-effectiveness ratios remained below $100,000 across a range of inputs and scenarios. In the PSA, the probability of olaparib being cost-effective at a $100,000 per QALY threshold was 99%. CONCLUSIONS: Compared to surveillance, olaparib increases both the LYs and QALYs of women with newly diagnosed advanced ovarian cancer and with a germline or somatic BRCA mutation. Olaparib offers a cost-effective maintenance option for these women from a US third-party payer perspective.

Movement of Poly-ADP Ribose (PARP) Inhibition into Frontline Treatment of Ovarian Cancer.

The use of poly (ADP-ribose) polymerase (PARP) inhibitors in the front-line management of advanced ovarian cancer has recently emerged as an exciting strategy with the potential to improve outcomes for patients with advanced ovarian cancer. In this article, we review the results of four recently published Phase III randomised controlled trials evaluating the use of PARP inhibitors in the primary treatment of ovarian cancer (SOLO1, PRIMA, PAOLA-1, and VELIA). Collectively, the studies suggest that PARP maintenance in the upfront setting is most beneficial among patients with BRCA-associated ovarian cancers (hazard ratios range from 0.31 to 0.44), followed by patients with tumours that harbour homologous recombination deficiencies (hazard ratios range from 0.33 to 0.57). All three studies that included an all-comer population were able to demonstrate benefit of PARP inhibitors, regardless of biomarker status. The FDA has approved olaparib for front-line maintenance therapy among patients with BRCA-associated ovarian cancers, and niraparib for all patients, regardless of biomarker status. In determining which patients should be offered front-line maintenance PARP inhibitors, and which agent to use, there are multiple factors to consider, including FDA indication, dosing preference, toxicity, risks versus benefits for each patient population, and cost. There are ongoing studies further exploring the front-line use of PARP inhibitors, including the potential downstream effects of PARP-inhibitor resistance in the recurrent setting, combining PARP-inhibitors with other anti-angiogenic drugs, immunotherapeutic agents, and inhibitors of pathways implicated in PARP inhibitor resistance.

Niraparib maintenance in frontline management of ovarian cancer: a cost effectiveness analysis.

OBJECTIVES: Niraparib maintenance after frontline chemotherapy for advanced ovarian cancer extends progression free survival. The objective of this study was to determine the cost effectiveness of niraparib maintenance therapy in patients with newly diagnosed ovarian cancer. METHODS: Decision analysis models compared the cost of observation versus niraparib maintenance following chemotherapy for five groups: all newly diagnosed ovarian cancer patients (overall), those with homologous recombination deficiency, those harboring BRCA mutations (BRCA), homologous recombination deficiency patients without BRCA mutations (homologous recombination deficiency non-BRCA), and non-homologous recombination deficiency patients. Drug costs were estimated using average wholesale prices. Progression free survival was estimated from published data and used to estimate projected overall survival. Incremental cost effectiveness ratios per quality adjusted life year were calculated. Sensitivity analyses varying the cost of niraparib were performed. The willingness-to-pay threshold was set at US$100 000 per quality adjusted life year saved. RESULTS: For the overall group, the cost of observation was US$5.8 billion versus $20.5 billion for niraparib maintenance, with an incremental cost effectiveness ratio of $72 829. For the homologous recombination deficiency group, the observation cost was $3.0 billion versus $14.8 billion for niraparib maintenance (incremental cost effectiveness ratio $56 329). Incremental cost effectiveness ratios for the BRCA, homologous recombination deficiency non-BRCA, and non-homologous recombination deficiency groups were $58 348, $50 914, and $88 741, respectively. For the overall and homologous recombination deficiency groups, niraparib remained cost effective if projected overall survival was 2.2 and 1.5 times progression free survival, respectively. CONCLUSIONS: For patients with newly diagnosed ovarian cancer, maintenance therapy with niraparib was cost effective. Cost effectiveness was improved when analyzing those patients with homologous recombination deficiency and BRCA mutations. Efforts should continue to optimize poly-ADP-ribose polymerase utilization strategies.

Real world experience of poly (ADP-ribose) polymerase inhibitor use in a community oncology practice.

OBJECTIVE: This study aims to describe the real-world experience, including the clinical and financial burden, associated with PARP inhibitors in a large community oncology practice. METHODS: Retrospective chart review identified patients prescribed olaparib, niraparib or rucaparib for maintenance therapy or treatment of recurrent ovarian, primary peritoneal or fallopian tube cancer across twelve gynecologic oncologists between December 2016 and November 2018. Demographic, financial and clinical data were extracted. One PARP cycle was defined as a single 28-day period. For patients treated with more than one PARPi, each course was described separately. RESULTS: A total of 47 patients and 506 PARP cycles were identified (122 olaparib, 24%; 89 rucaparib, 18%; 294 niraparib, 58%). Incidence of grade ≥ 3 adverse events were similar to previously reported. Toxicity resulted in dose interruption, reduction and discontinuation in 69%, 63% and 29% respectively. Dose interruptions were most frequent for niraparib but resulted in fewer discontinuations (p-value 0.01). Mean duration of use was 7.46 cycles (olaparib 10.52, rucaparib 4.68, niraparib 7.34). Average cost of PARPi therapy was $8018 per cycle. A total of 711 phone calls were documented (call rate 1.4 calls/cycle) with the highest call volume required for care coordination, lab results and toxicity management. CONCLUSIONS: Although the toxicity profile was similar to randomized clinical trials, this real-world experience demonstrated more dose modifications and discontinuations for toxicity management than previously reported. Furthermore, the clinical and financial burden of PARP inhibitors may be significant and future studies should assess the impact on patient outcomes.

Poly (ADP-ribose) polymerase (PARP) inhibitor regimens for ovarian cancer in phase III randomized controlled trials: a network meta-analysis.

INTRODUCTION: We aimed to evaluate poly (ADP-ribose) polymerase (PARP) inhibitor (PARPi) regimens in BRCA-mutated ovarian cancer for patients responsive to front-line platinum (bevacizumab and olaparib, veliparib and chemotherapy, olaparib) or platinum-sensitive relapsed (olaparib, rucaprib, niraparib) patients in phase III randomized controlled trials. METHODS: A network meta-analysis was utilized to generate the direct and indirect comparisons. The primary outcomes for network meta-analysis were efficacy (hazard ratios for progression-free survival in BRCA mutation cohort) and toxicity (odds ratios for all grade 3-4 adverse events). The American Society of Clinical Oncology (ASCO) value framework was used to assess the cost-effectiveness of the PARPi regimens. RESULTS: Network meta-analysis indicated no statistically significant differences in efficacy and toxicity among the assessed upfront or relapsed PARPi regimens (95% CI included 1). The ASCO value framework indicated that current PARPi regimens were similar in clinical benefits, toxicity, and net health benefit in the upfront (bevacizumab and olaparib, veliparib and chemotherapy, olaparib) and relapsed setting (olaparib, rucaprib, niraparib). The addition of bevacizumab to olaparib ($353.72) increased the cost per unit net health benefit for patients compared with olaparib monotherapy ($260.57). The upfront PARPi regimens had lower toxic scores than the regimens used at relapse. CONCLUSIONS: The choice of PARPi regimens both in the upfront and relapsed setting should consider not only efficacy and toxicity but also costs in BRCA mutation patients. Current combining PARPi regimens are not recommended for such patients in the upfront setting from the cost-effective perspective. Upfront PARPi regimens are less toxic than those used at relapse.

Metabolic Stability Assessment of New PARP Inhibitor Talazoparib Using Validated LC-MS/MS Methodology: In silico Metabolic Vulnerability and Toxicity Studies.

BACKGROUND: Talazoparib (BMN673) is a new poly(ADP-ribose) polymerase inhibitor that has been FDA approved for patients suffering from metastatic breast cancer with germline BRCA mutations. METHOD AND RESULTS: In the current study, an accurate and efficient liquid chromatography-tandem mass spectrometry (LC-MS/MS) analytical methodology was developed for TZB estimation in addition to its metabolic stability assessment. TZB and lapatinib (LAP) (which is chosen as an internal standard; IS) were separated using reversed phase elution system (Hypersil C18 column) with an isocratic mobile phase. The linearity range of the established method was 5-500 ng/mL (r2 ≥ 0.999) in the human liver microsomes (HLMs) matrix. Different parameters were calculated to confirm the method sensitivity (limit of quantification was 2.0 ng/mL), and reproducibility (intra- and inter-day precision and accuracy were below 3.1%) of our methodology. For evaluation of TZB metabolic stability in HLM matrix, intrinsic clearance (9.59 µL/min/mg) and in vitro half-life (72.7 mins) were calculated. TZB treatment discontinuations were reported due to adverse events and dose accumulation, so in silico metabolic vulnerability (experimental and in silico) and toxicity assessment (in silico) of TZB were performed utilizing P450 Metabolism and DEREK modules of StarDrop software. CONCLUSION: TZB is slowly metabolized by the liver. TZB was reported to be minimally metabolized by the liver that approved our outcomes. We do recommend that plasma levels be monitored in cases when talazoparib is used for a long period of time, since it is possible for TZB to bioaccumulate after multiple doses to toxic levels. According to our knowledge, the current method is considered the first LC-MS/MS methodology for evaluating TZB metabolic stability. Further drug discovery studies can be done depending on this concept allowing the designing of new series of compounds with more safety profile through reducing side effects and improving metabolic behavior.

Cost-effectiveness of niraparib, rucaparib, and olaparib for treatment of platinum-resistant, recurrent ovarian carcinoma.

BACKGROUND: Olaparib was approved on December 19, 2014 by the US FDA as 4th-line therapy (and beyond) for patients with germline BRCA1/2 mutations; rucaparib was approved on December 19, 2016 as 3rd-line therapy (and beyond) for germline or somatic BRCA1/2-mutated recurrent disease. On October 23, 2019, niraparib was approved for treatment of women with damaging mutations in BRCA1/2 or other homologous recombination repair genes who had been treated with three or more prior regimens. We compared the cost-effectiveness of PARPi(s) with intravenous regimens for platinum-resistant disease. METHODS: Median progression-free survival (PFS) and toxicity data from regulatory trials were incorporated in a model which transitioned patients through response, hematologic complications, non-hematologic complications, progression, and death. Using TreeAge Pro 2017, each PARPi(s) was compared separately to non­platinum-based and bevacizumab-containing regimens. Costs of IV drugs, managing toxicities, infusions, and supportive care were estimated using 2017 Medicare data. Incremental cost-effectiveness ratios (ICERs) were calculated and PFS was reported in quality adjusted life months for platinum-resistant populations. RESULTS: Non­platinum-based intravenous chemotherapy was most cost effective ($6,412/PFS-month) compared with bevacizumab-containing regimens ($12,187/PFS-month), niraparib ($18,970/PFS-month), olaparib ($16,327/PFS-month), and rucaparib ($16,637/PFS-month). ICERs for PARPi(s) were 3-3.5× times greater than intravenous non­platinum-based regimens. CONCLUSION: High costs of orally administered PARPi(s) were not mitigated or balanced by costs of infusion and managing toxicities of intravenous regimens typically associated with lower response and shorter median PFS. Balancing modest clinical benefit with costs of novel therapies remains problematic and could widen disparities among those with limited access to care.

Patient preferences for maintenance PARP inhibitor therapy in ovarian cancer treatment.

OBJECTIVE: To measure preferences of women with ovarian cancer regarding risks, side effects, costs and benefits afforded by maintenance therapy (MT) with a poly ADP ribose polymerase (PARP) inhibitor. METHODS: A discrete-choice experiment elicited preferences of women with ovarian cancer regarding 6 attributes (levels in parentheses) relevant to decisions for MT versus treatment break: (1) overall survival (OS; 36, 38, 42 months); (2) progression-free survival (PFS; 15, 17, 21 months); (3) nausea (none, mild, moderate); (4) fatigue (none, mild, moderate); (5) probability of death from myelodysplastic syndrome/acute myelogenous leukemia (MDS/AML; 0% to 10%); (6) monthly out-of-pocket cost ($0 to $1000). Participants chose between 2 variable MT scenarios and a static scenario representing treatment break, with multiple iterations. Random-parameters logit regression was applied to model choices as a function of attribute levels. RESULTS: 95 eligible participants completed the survey; mean age was 62, 48% had recurrence, and 17% were ever-PARP inhibitor users. Participants valued OS (average importance weight 24.5 out of 100) and monthly costs (24.6) most highly, followed by risk of death from MDS/AML (17.9), nausea (14.7), PFS (10.5) and fatigue (7.8). Participants would accept 5% risk of MDS/AML if treatment provided 2.2 months additional OS or 4.8 months PFS. Participants would require gains of 2.6 months PFS to accept mild treatment-related fatigue and 4.4 months to accept mild nausea. CONCLUSIONS: When considering MT, women with ovarian cancer are most motivated by gains in OS. Women expect at least 3-4 months of PFS benefit to bear mild side effects of treatment.

PARP-inhibitor potpourri: A comparative review of class safety, efficacy, and cost.

Purpose: To summarize similarities and differences in efficacy, safety, and cost of available PARP-inhibitors and offers pearls to distinguish subtle nuances between each agent to help guide therapy. Summary: Currently, four PARP-inhibitors (olaparib, rucaparib, niraparib, and talazoparib) are FDA-approved, with olaparib, rucaparib, and niraparib approved for treatment and/or maintenance or ovarian cancer and olaparib and talazoparib approved for the treatment of recurrent metastatic BRCA-mutant, HER2-negative breast cancer. While the PARP-inhibitor class is generally are well-tolerated, each agent does possess a unique side-effect profile. Niraparib and talazoparib have more prominent hematologic adverse event profiles, while niraparib has an increased risk of cardiac events. In patients using other medications with known drug interactions, niraparib may be the preferred option for patients with ovarian cancer, and talazoparib may be the preferred option for patients with breast cancer because neither of these agents undergo hepatic metabolism. These agents also can incur large financial toxicities for patients, and olaparib currently has the broadest range of options for financial assistance. Conclusion: Although these agents have similar approved indications, efficacy, and toxicity profiles, there are notable differences that may help direct choice of therapy and optimize treatment for patients. It is important to incorporate patient-specific factors to optimize PARP-inhibitor therapy for patients.

Budget impact analysis of niraparib and olaparib for maintenance treatment of platinum-sensitive, recurrent ovarian cancer in the US.

AIMS: This study aimed to evaluate the budget impact of niraparib and olaparib in patients with platinum-sensitive, recurrent ovarian cancer from a US third party payer perspective. MATERIALS AND METHODS: A budget impact model was constructed to assess the additional per member per month (PMPM) costs associated with the introduction of niraparib and olaparib, two poly ADP-ribose polymerase ribose polymerase (PARP) inhibitors recently approved to be used in platinum-sensitive, recurrent ovarian cancer patients with and without a gBRCA mutation. The model assessed both pharmacy costs and medical costs. Pharmacy costs included adjusted drug costs, coinsurance, and dispensing fees. Medical costs included costs associated with disease monitoring and management of adverse events from the treatment. Epidemiological data from the literature were used to estimate the target population size. The analysis used 1-year time frame, and patients were assumed on treatment until disease progression or death. All costs were computed in 2017 USD. One-way sensitivity analyses were conducted to evaluate the model robustness. RESULTS: In a hypothetical plan of 1,000,000 members, 206 patients were estimated to be potential candidates for niraparib or olaparib maintenance treatment after applying all epidemiological parameters. At listed 30-day supply WAC prices of $14,750 for niraparib and $13,482 for olaparib, budget impacts of these two drugs were $0.169 PMPM and $0.156 PMPM, respectively, most of which were contributed by pharmacy costs. Sensitivity analyses suggested that assumptions around market share, platinum-sensitive rate after first treatment, and WAC prices affected results the most. LIMITATIONS: In this model, it was assumed that adopting niraparib and olaparib would not affect utilization of existing medications. Also, the estimated clinical parameters from clinical trials could differ from real-world data.