Palbociclib or Ribociclib in First-Line Treatment in Patients With Hormone Receptor–Positive/Human Epidermal Receptor 2–Negative Advanced or Metastatic Breast Cancer? A Perspective Based on Pharmacologic Costs

Cost Effectiveness of CDK4/6 Inhibitors in the First-Line Treatment of HR+/HER2- Metastatic Breast Cancer in Postmenopausal Women in the USA

BACKGROUND AND OBJECTIVE

Cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitors improve progression-free survival when combined with endocrine therapies in patients with hormone receptor-positive/human epidermal growth factor receptor 2-negative metastatic breast cancer. However, the comparative cost effectiveness of utilizing three US Food and Drug Administration-approved CDK4/6 inhibitors is unknown. Therefore, we aimed to evaluate the cost effectiveness of individual CDK4/6 inhibitors (palbociclib, ribociclib, abemaciclib) with letrozole versus letrozole monotherapy in the first-line treatment of hormone receptor-positive/human epidermal growth factor receptor 2-negative metastatic breast cancer in the USA.

METHODS

We constructed a Markov-based decision-analytic model to evaluate the cost effectiveness of CDK4/6 inhibitors plus endocrine therapies over a 40-year lifetime from a third-party payer perspective. The model incorporated health states (progression-free disease, progressive disease, and death), major adverse events (neutropenia), and cancer-specific and all-cause mortality. Using clinical efficacy and quality-of-life scores (utility) data from clinical trials, we estimated quality-adjusted life-years (QALYs) and incremental cost-effectiveness ratios using Medicare charges reported in US dollars per 2022 valuation and a discount rate of 3% applied to costs and outcomes. We performed deterministic and probabilistic sensitivity analyses to evaluate parametric and decision uncertainty.

RESULTS

Compared to letrozole, the model estimated an increase of 5.72, 5.87, and 6.39 in QALYs and costs of $799,178, $788,168, and $741,102 in combining palbociclib, ribociclib, and abemaciclib plus letrozole, respectively. Palbociclib or ribociclib plus letrozole were dominated by abemaciclib plus letrozole. Compared with letrozole, abemaciclib plus letrozole resulted in an incremental cost-effectiveness ratio of $457,538 per QALY with an incremental cost of $553,621 and an incremental QALY gain of 1.21. The results were sensitive to the cost of abemaciclib, disease progression utility, and patients' age.

CONCLUSIONS

At a willingness to pay of $100,000/QALY gained, our model predicts that combining CDK4/6 inhibitors plus letrozole is not cost effective with a marginal increase in QALYs at a high cost. Lowering the cost of these drugs or identifying patients who can receive maximal benefit from CDK4/6 inhibitors would improve the value of this regimen in patients.

Real world evidence study on treatment patterns and health resource utilization in patients with HR+/HER2- locally advanced or metastatic breast cancer in Korea

Objective

To understand current treatment patterns and health care resource utilization (HRU) of women with locally advanced or metastatic breast cancer (advanced breast cancer; ABC) in Korea overall and within patients who had progressed with prior endocrine therapy (as first-line treatment for metastatic disease) and patients with no prior systemic treatment (for advanced disease).

Methods

A chart review was conducted in 109 patients (women ≥ 18 years old with HR+/HER2- ABC diagnosed between 2015 and 2017) from 11 hospitals. Anonymized data on patient characteristics, treatment patterns and HRU was abstracted.

Results

Mean (range) age of all patients was 57.5 (40–81) years. Overall, the most common first-, second- and third-line systemic therapy after diagnosis of ABC were letrozole ± palbociclib (51%), endocrine therapy (ET)±everolimus (42%) or chemotherapy (ChT) (39%), and ChT (68%), respectively. In patients progressed with ET (n = 33) and those with no prior systemic treatment (n = 52), the most common first-line treatments were letrozole (82%) and letrozole + palbociclib (42%), respectively. The percentage of patients with at least one grade 3 or higher adverse event during first-line therapy was 93.1% vs 39.2% in patients on a ChT based regimen (N = 29) vs. ET (N = 74). Overall, oncologist visits, at an annual rate of 9.27 (95% CI: 8.87, 9.69) visits per month, and hospitalizations, with an annual rate of 0.44 (95% CI: 0.36, 0.54), and mean (SD) length of stay of 14.3 (10.32) days, were the key drivers of HRU.

Conclusions

These findings on real world HRU reflected clinical guidelines and severity of ABC. Results can inform future evaluations of new ABC treatments that estimate the health economic impact of their adoption in Korea.

Pharmacoeconomic evaluations of CDK4/6 inhibitors plus endocrine therapy for advanced hormone receptor-positive (HR+) and human epidermal growth factor receptor-2 negative (HER2-) breast cancer: a systematic review

Background

Hormone receptor-positive (HR+) and human epidermal growth factor receptor-2 negative (HER2−) breast cancer is the most common molecular subtype of breast cancer in many countries, and endocrine therapy remains a mainstay in its treatment. Cyclin-dependent kinase (CDK) 4/6 inhibitors are a new class of targeted agents administered orally that are recommended being used in combination with endocrine therapy as first and second line treatments for advanced HR+/HER2− breast cancer. However, their high prices largely hinder using these drugs in real world settings. To offer a new basis for future research, we investigated the cost-effectiveness of combinations of CDK4/6 inhibitors with endocrine therapy in the treatment of advanced HR+/HER2− breast cancer.

Methods

We systematically searched several frequently used databases and identified economic evaluations published from February 2015 to April 2021. The systematic review was performed after retrieving the literatures and extracting data based on inclusion and exclusion criteria. The quality of each selected economic evaluation was assessed by the Consolidated Health Economic Evaluation Reporting Standards (CHEERS).

Results

The literature search yielded 161 articles, among which fourteen studies (15 articles) with CHEER scores ranging from 58.33% to 87.50% entered the final analysis. Markov models were used in most studies. Based on the currently available data, CDK4/6 inhibitors plus endocrine therapy were less cost-effective in first- or second-line treatment of patients with HR+/HER2− advanced breast cancer. However, ribociclib plus letrozole was more cost-effective than palbociclib plus letrozole in the first-line treatment of postmenopausal women. The economic impacts of CDK4/6 inhibitors plus endocrine therapy in non-postmenopausal patients or second-line therapy cannot be fully evaluated due to the limited number of studies. The three most common factors affecting economic outcomes were the prices of CDK4/6 inhibitors, hazard ratios for progression-free survival and overall survival, and health status utility values.

Discussion

CDK4/6 inhibitors plus endocrine therapy have shown significantly improved efficacy outcomes in HR+/HER2− metastatic breast cancer (mBC)/advancer breast cancer (ABC) first-line and second-line treatment for endocrine-sensitive and endocrine-resistant populations, while more potential fields including neoadjuvant and adjuvant settings are being identified to benefit a wider range of breast cancer patients. Meanwhile, risk of severe adverse events that more likely to happen in patients treated with CDK4/6 inhibitors can lead to reduced life quality and higher medical costs patients need to afford. The adverse drug reaction related cost in several economic burden studies were explored to be primarily driven by hospitalizations and outpatient, and assessment of cost associated with CDK4/6 inhibitors adverse events is worth further developing. Drug wastage costs were found higher in palbociclib regimen than ribociclib regimen due to different dosing patterns. Moreover, current economic evaluations showed that ribociclib plus letrozole had better economic benefits than palbociclib plus letrozole for first-line treatment of postmenopausal women with HR+/HER2− ABC.

Social and economic burden of breast cancer in the North East region of Bulgaria

Introduction: Breast cancer is one of the most common malignancies among women and significantly worsens physical, mental and social functioning. The aim is to evaluate the social and economic burden of treatment strategies for breast cancer in the North East region of Bulgaria.Areas covered: A retrospective, observational, population-based study among patients with breast cancer was performed. Patient characteristics, treatment patterns, and costs were assessed during a four-year period (2016-2019). Disability-adjusted life years (DALYs) were calculated to estimate the social burden.Results: Approximately 99% of patients (n = 1,373) were female and the mean age at diagnosis was 60.6 years. The total economic burden of breast cancer during the time of the study was estimated to be 21,076,809.12 BGN where the direct costs were equal to 19,634,509.67 BGN and the total indirect costs due to premature death amounted to 1,442,299.45 BGN. Total DALYs were 110.56 for all patients corresponding to 1,898,340.80 BGN.Conclusions: This study demonstrates the significant social and economic burden of breast cancer as further, more comprehensive regional and national-based studies related to the total economic burden of breast cancer are required.

The introduction of a third CDK4/6 inhibitor does not change the cost-effectiveness profile in first and subsequent-lines after progression or relapse during previous endocrine therapy in patients with hormone receptor positive (HR+)/human epidermal receptor-2 negative (HER-2) advanced or metastatic breast cancer

The aim of this study was to assess the pharmacological costs of CDK4/6-inhibitors (palbociclib, ribociclib and abemaciclib) in hormone receptor positive (HR+)/human epidermal receptor 2-negative (HER2-) advanced or metastatic breast cancer (BC). We have considered pivotal phase III randomized controlled trials (RCTs) of palbociclib, ribociclib and abemaciclib for the treatment of postmenopausal women with HR+/HER2- advanced or metastatic BC in first-line in association with letrozole or anastrozole (scenario 1) and in subsequent-lines after progression or relapse during previous endocrine therapy (scenario 2).The costs of drugs are at the Pharmacy of our Hospital and are expressed in euros (€). Six phase III RCTs, including 3843 patients, were considered. In the scenario 1, abemaciclib resulted the less expensive at the full dose, with 2246 € per month of progression free survival (PFS)-gained. Overall ribociclib resulted the less expensive considering the reduction in dosage (36.1% in MONALEESA-2 trial versus (vs). 36.0% of palbociclib in PALOMA-2 trial vs. 43.4% of abemaciclib in MONARCH-3 trial). The price was the same for palbociclib and abemaciclib both at full and with dose reduction. In the scenario 2, the situation was similar to the scenario 1, but with lowest costs for ribociclib per month PFS-gained both at full dose (2070 €) and at dose reduction (1391 € and 690 € at 400 mg and 200 mg, respectively). Combining pharmacological costs of drugs with the measure of efficacy represented by the PFS, ribociclib was the less expensive in both scenarios.