Cost-effectiveness of maintenance hormonal therapy in patients with advanced low grade serous ovarian cancer.

OBJECTIVES: To assess the cost-effectiveness of using maintenance hormonal therapy in patients with low grade serous ovarian cancer (LGSC). METHODS: A simulated decision analysis with a Markov decision model over a lifetime horizon was performed using the base case of a 47-year old patient with stage IIIC, LGSC following first-line treatment with primary cytoreductive surgery and adjuvant chemotherapy. Two treatment strategies were analyzed - maintenance daily letrozole until disease progression and routine observation. The analysis was from the perspective of the healthcare payer. Direct medical costs were estimated using public data sources and previous literature and were reported in adjusted 2018 Canadian dollars. The model estimated lifetime cost, quality-adjusted life years (QALY), life years (LY), median overall survival (OS), and number of recurrences with each strategy. Cost-effectiveness was compared using an incremental cost-effectiveness ratio (ICER). A strategy was considered cost-effective when the ICER was less than the willingness to pay (WTP) threshold of $50,000 CAD per QALY. Deterministic sensitivity analysis was performed to assess the impact of changing key clinical and cost variables. RESULTS: Maintenance letrozole was the preferred strategy with an associated lifetime cost of $69,985 CAD ($52,620 USD) and an observed improvement of 0.91 QALYs and 1.55 LYs. The ICER for letrozole maintenance therapy was an additional $11,037 CAD ($8298 USD) per QALY. The modeled median OS was 150 months with maintenance letrozole and 126 months in the observation strategy. The maintenance letrozole strategy resulted in 34% and 17% fewer first recurrences at 5-year and 10-year follow-up, respectively. CONCLUSION: Maintenance letrozole is a cost-effective treatment strategy in patients with advanced LGSC resulting in clinically-relevant improvement in QALYs, LYs, and fewer disease recurrences.

Cost-effectiveness analysis of palbociclib or ribociclib in the treatment of advanced hormone receptor-positive, HER2-negative breast cancer.

PURPOSE: Three CDK4/6 inhibitors, palbociclib (PAL), ribociclib (RIB), and abemaciclib, when combined with letrozole (LET), have been approved as first-line therapy for postmenopausal women with metastatic HR+, HER2- breast cancer. However, an economic evaluation of these newer therapies is currently lacking. The purpose of this article is to evaluate the cost-effectiveness of PAL or RIB for the treatment of advanced HR+, HER2- breast cancer in the United States. METHODS: A Markov simulation model was constructed using data from published clinical trials evaluating PAL and RIB. Three simulated treatment strategies included PAL + LET, RIB + LET, or LET alone. The main outcome measures were simulated progression-free survival (PFS), overall survival (OS), costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios (ICERs). RESULTS: Simulated median OS was 38.9 months for PAL + LET and 33.0 months for LET alone. Simulated median OS for RIB + LET was 43.3 months. Compared to LET alone, PAL + LET provided an additional 0.48 QALYs, on average, with an ICER of $634,000 per QALY gained; RIB + LET provided an additional 0.86 QALYs, on average, with an ICER of $440,000 per QALY gained. At current prices, neither PAL nor RIB was cost-effective, assuming a willingness-to-pay threshold of $100,000 per QALY gained. To reach such a cost-effectiveness threshold, PAL and RIB prices must decrease by approximately 70%. CONCLUSION: Despite significant gains in progression-free survival over letrozole alone, the addition of palbociclib or ribociclib in the treatment of advanced HR+, HER2- breast cancer is not cost-effective in the United States given current drug prices.

Misclassification in Assessment of First Trimester In-utero Exposure to Drugs Used Proximally to Conception: the Example of Letrozole Utilization for Infertility Treatment.

Letrozole is an aromatase inhibitor that has an unapproved use for ovulation induction with infertility. Because of the proximity of this use to conception, we selected letrozole to study the effect of 3 different methods for identifying the pregnancy start date and their impact on exposure misclassification. Using electronic health data from the US Sentinel database (2001-2015), we identified live-birth pregnancies conceived through in-vitro fertilization or intrauterine insemination. The pregnancy start was calculated using 1) a validated algorithm to estimate the last menstrual period (LMP), 2) LMP + 14 days (i.e., conception estimate), and 3) the fertility-procedure date. We identified 47,628 live-births after intrauterine insemination (n = 24,962) and in-vitro fertilization (n = 22,666), in which 2,458 (5.3%) mothers received letrozole. The algorithm-based conception estimate occurred within 14 days of the fertility procedure for 78.3% of pregnancies. Defining pregnancy start as LMP (45.7/1,000 pregnancies) or LMP + 14 days (12.7/1,000 pregnancies) overestimated letrozole exposure during pregnancy by 8.4-fold and 2.3-fold, respectively, compared with defining it at the date of the fertility procedure (5.5/1,000 pregnancies). While most studies of drug utilization in pregnancy use LMP as the conventional pregnancy start, this introduced substantial exposure misclassification in the example of letrozole. LMP + 14 days was less biased. Researchers should carefully consider the impact of the method for identifying the pregnancy start date on the potential for exposure misclassification.

Ribociclib in hormone-receptor-positive advanced breast cancer: Establishing a value-based cost in China.

BACKGROUND: The addition of ribociclib (RIB) to letrozole (LET) significantly increases progression free survival for patients with hormone-receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer (ABC). We identified the range of drug costs for which RIB could be considered cost effective from a Chinese perspective. METHODS: A discrete event simulation model was developed to model the treatment sequences among patients with ABC. Life years (LYs), quality-adjusted LYs (QALYs) and lifetime costs were estimated. Costs were estimated for Chinese health care systems. Three times the per capita gross domestic product (GDP) of China 2016 ($24,360) and three times the per capita GDP of Beijing city 2016 ($53,384) were used as the willingness-to-pay threshold. Probabilistic sensitivity analyses were performed. RESULTS: In the base case analysis, RIB + LET provided an incremental survival benefit of 0.631 LYs and 0.451 QALYs. When RIB costs less than $721 or $1170 per 4 weeks, there was a nearly 90% likelihood that the incremental cost-effectiveness ratio for RIB + LET would be less than $24,360 per QALY or $53,384 per QALY, respectively. CONCLUSION: A value-based price for the cost of RIB is $732 or $1170 per 4 weeks for China and Beijing City, respectively. Our study is helpful to inform the multilateral drug price negotiations in China that may be upcoming for RIB.

Budget impact of including ribociclib in combination with letrozole on US payer formulary: first-line treatment of post-menopausal women with HR+/HER2- advanced or metastatic breast cancer.

OBJECTIVES: The combination of a cyclin-dependent kinase 4 and 6 (CDK 4/6) inhibitor with the aromatase inhibitor letrozole is a safe and effective alternative to letrozole monotherapy for first-line hormone receptor-positive (HR+)/human epidermal growth factor receptor 2-negative (HER2-) breast cancer. This study evaluates the budget impact of using the CDK 4/6 inhibitor ribociclib plus letrozole as a first-line treatment option for postmenopausal women with HR+/HER2- advanced breast cancer, from a United States (US) payer perspective. METHODS: A cohort-based budget impact model was used to calculate the incremental cost of introducing ribociclib plus letrozole over three years for the target population. The analysis compared two scenarios: treatment options excluding or including ribociclib plus letrozole. Market shares were derived from market research and the assumption was the introduction of ribociclib plus letrozole would only displace existing CDK-based therapies. Treatment duration was based on the median time to treatment discontinuation or median progression-free survival for first-line treatment, and on clinical trial data for second- and third-line treatment. Acquisition costs were based on wholesale acquisition costs and considered co-payment. Costs for drug administration and monitoring, subsequent therapy, and relevant adverse events were included. RESULTS: Of 1 million insured members, 263 were eligible for CDK 4/6 inhibitor treatment. Cumulative total savings with ribociclib plus letrozole were $3.01M over three years, corresponding to a cumulative incremental cost saving of $318.11 per member treated per month. CONCLUSIONS: In the US, ribociclib plus letrozole represents a cost-saving first-line treatment option for postmenopausal women with HR+/HER2- advanced breast cancer.