A Critical Appraisal and Recommendations for Cost-Effectiveness Studies of Poly(ADP-Ribose) Polymerase Inhibitors in Advanced Ovarian Cancer

Cost-Effectiveness Analysis of Biomarker Testing to Guide First-Line PARP Inhibitor Maintenance for Patients with Advanced Ovarian Cancer After Response to First-Line Platinum Chemotherapy in the USA

BACKGROUND

Poly(ADP-ribose) polymerase inhibitor maintenance treatments are available for platinum-sensitive advanced ovarian cancer. Olaparib (O) is available for BRCA mutation patients or in combination with bevacizumab (O+B) for patients with homologous recombination deficiency (HRD+); niraparib (N) is available for all patients.

OBJECTIVE

This study aimed to evaluate the cost effectiveness of biomarker testing and maintenance treatments (mTx) with poly(ADP-ribose) polymerase inhibitor in platinum-sensitive advanced ovarian cancer in the USA.

PATIENTS AND METHODS

Ten strategies were evaluated (S1-S10), representing biomarker testing (none, BRCA or HRD), and mTx (O, O+B, N or B). PAOLA-1 data were used to build a model estimating progression-free survival (PFS), second PFS (PFS2) and overall survival for O+B. PFS was modelled through mixture cure models; PFS2 and overall survival were modelled by standard parametric models. Hazard ratios of PFS for O+B versus B, N and O were obtained from the literature to estimate PFS for B, N and O. PFS2 and OS for B, N and O were informed by PFS benefits.

RESULTS

S2 (no testing, B) had the lowest cost while S10 (HRD testing, O+B for HRD+ and B for HRD-) had the highest quality-adjusted life-years (QALYs). All niraparib strategies were dominated. S2, S4 (BRCA testing, O for BRCA+ and B for BRCA-), S6 (BRCA testing, olaparib plus bevacizumab for BRCA+ and bevacizumab for BRCA-) and S10 were the non-dominated strategies with an incremental cost-effectiveness ratio of $29,095/QALY, $33,786/QALY and $52,948/QALY for S4 versus S2, S6 versus S4 and S10 versus S6, respectively.

CONCLUSIONS

Homologous recombination deficiency testing followed by O+B for HRD+ and B for HRD- is a highly cost-effective strategy for patients with platinum-sensitive advanced ovarian cancer. A HRD biomarker-guided approach provides most QALYs with good economic value.

Cost-effectiveness of PARP inhibitors in malignancies: A systematic review

OBJECTIVES

Poly (ADP-ribose) polymerase inhibitor (PARPi) have become a mainstay for the treatment of BRCA-mutant malignancies. PARPis are likely to be more effective but also bring an increase in costs. Thus, we aimed at evaluating the cost effectiveness of PARPis in the treatment of malignancies.

METHODS

Studies of cost effectiveness of PARPis were searched from PubMed, Web of Science, and Cochrane Library. Key information was extracted from the identified studies and reviewed. Quality of the included studies was evaluated using Quality of Health Economic Studies (QHES) instrument. Modeling techniques, measurement of parameters and uncertainty analysis were analyzed across studies. Interventions and cost-effectiveness results were reported stratified by patient population.

RESULTS

Among the 25 studies identified, we included 17 on ovarian cancer, 2 on breast cancer, 3 on pancreatic cancer, and 3 on prostate cancer that involved olaparib, niraparib, rucaparib, and talazoparib. All studies had a QHES score of above 75. In the maintenance therapy of ovarian cancer, additional administration of olaparib was cost-effective for newly diagnosed patients after first-line platinum-based chemotherapy but was not cost-effective for platinum-sensitive recurrent patients in majority studies. However, the economic value of other PARPis in ovarian cancer as well as all PARPis in other tumors remained controversial. Cost-effectiveness of PARPi was primarily impacted by the costs of PARPi, survival time, health utility and discount rate. Moreover, genetic testing improved the cost-effectiveness of PARPi treatment.

CONCLUSIONS

PARPi is potentially cost-effective for patients with ovarian, pancreatic, or prostate cancer. Genetic testing can improve the cost-effectiveness of PARPi.

Cost-Effectiveness Analysis of Olaparib in Combination with Bevacizumab Compared with Bevacizumab Monotherapy for the First-Line Maintenance Treatment of Homologous Recombination Deficiency-Positive Advanced Ovarian Cancer

BACKGROUND

In the PAOLA-1 trial, olaparib plus bevacizumab demonstrated significant clinical benefit following partial or complete response to platinum-based chemotherapy in homologous recombination deficiency (HRD)-positive ovarian cancer. Our study evaluated the cost effectiveness of olaparib plus bevacizumab compared with bevacizumab alone as a maintenance treatment for women in this population.

METHODS

Our model was a cohort-level partitioned survival model with a lifetime horizon from a US healthcare system perspective. Its four health states were progression-free, post first progression, post second progression, and death, modeled using time to first progression (PFS1), second progression (PFS2), and overall survival (OS) from PAOLA-1. We modeled PFS1 through mixture survival modeling, and PFS2 and OS by fitting standard parametric models. Time-on-treatment was sourced directly from PAOLA-1, with treatment capped at 24 months for olaparib and 15 months for bevacizumab. Costs included drug acquisition and administration, adverse events, disease management, biomarker testing, and subsequent treatments. Deterministic and probabilistic sensitivity analyses tested the results.

RESULTS

Compared with bevacizumab alone, olaparib plus bevacizumab increased quality-adjusted life-years (QALYs; +2.89) and life-years (LYs; +3.43) at an incremental cost of $164,209, leading to an incremental cost-effectiveness ratio of $56,863 per QALY. Olaparib plus bevacizumab had a 97.0% probability of being cost effective compared with bevacizumab alone at a willingness-to-pay threshold of $100,000 per QALY.

CONCLUSION

The addition of olaparib to bevacizumab led to clinically significant increases in progression-free survival, resulting in substantial predicted LYs and QALYs gained, while being cost effective in the maintenance treatment of advanced ovarian cancer with HRD in the US.

Cost-Effectiveness of Poly ADP-Ribose Polymerase Inhibitors in Cancer Treatment: A Systematic Review

Background: PARP inhibitors have shown significant improvement in progression-free survival, but their costs cast a considerable financial burden. In line with value-based oncology, it is important to evaluate whether drug prices justify the outcomes.

Objectives: The aim of the study was to systematically evaluate PARP inhibitors on 1) cost-effectiveness against the standard care, 2) impact on cost-effectiveness upon stratification for genetic characteristics, and 3) identify factors determining their cost-effectiveness, in four cancer types.

Methods: We systematically searched PubMed, EMBASE, Web of Science, and Cochrane Library using designated search terms, updated to 31 August 2021. Trial-based or modeling cost-effectiveness analyses of four FDA-approved PARP inhibitors were eligible. Other studies known to authors were included. Reference lists of selected articles were screened. Eligible studies were assessed for methodological and reporting quality before review.

Results: A total of 20 original articles proceeded to final review. PARP inhibitors were not cost-effective as recurrence maintenance in advanced ovarian cancer despite improved performance upon genetic stratification. Cost-effectiveness was achieved when moved to upfront maintenance in a new diagnosis setting. Limited evidence indicated non–cost-effectiveness in metastatic breast cancer, mixed conclusions in metastatic pancreatic cancer, and cost-effectiveness in metastatic prostate cancer. Stratification by genetic testing displayed an effect on cost-effectiveness, given the plummeting ICER values when compared to the “treat-all” strategy. Drug cost was a strong determinant for cost-effectiveness in most models.

Conclusions: In advanced ovarian cancer, drug use should be prioritized for upfront maintenance and for patients with BRCA mutation or BRCAness at recurrence. Additional economic evaluations are anticipated for novel indications.