Abstract PO4-10-06: Cost-effectiveness analysis of ribociclib in the treatment for premenopausal or perimenopausal women with HR+/HER2− advanced breast cancer: a public health care system perspective in Mexico
Authors: Campos-Gomez Saúl , Piña Christian Pichardo 
Published: May 2024

BACKGROUND: Ribociclib (RIB) an inhibitor of cyclin-dependent kinase 4 and 6 for the treatment of advanced breast cancer (ABC), has demonstrated significant efficacy in prolonging progression-free survival and overall survival when added to endocrine therapy (ET). Because of the high-cost perception of this therapeutic class, it is crucial to assess their relative value compared to existing standards of care in the local setting.

Chemotherapy is used as the first line of treatment in a conservative case in almost three-quarters of ABC patients with positive hormone receptors in the Public Health System in Mexico. Additionally, the high use of chemotherapy presents additional clinical and economic challenges for the Institute. Among the clinical challenges, the toxicity associated with chemotherapy regimens stands out.

We evaluated the cost-effectiveness of the inclusion of RIB+ ET to usual care in the treatment of premenopausal or perimenopausal ABC from the perspective of the Public Health System in Mexico. Direct medical costs were considered.

METHODS: We developed a partitioned survival model to simulate time to cancer progression and to compare lifetime clinical benefit and cost of standard alternative treatment strategies for patients with metastatic disease. Per approved indication, endocrine treatment-naive patients were assigned to RI plus ET or usual care (different chemotherapy schemes). Costs in Mexican Pesos (MXN) were estimated from the perspective of the Public Health System in Mexico.

Costs and clinical benefits were discounted at 5% annually. The model assumptions were informed based on published clinical trial data from the randomized Phase III MONALEESA-7 trial and other peer-reviewed studies and indirect treatment comparisons. We carried out one-way and probabilistic sensitivity analyses to assess the robustness of our results to the changes in model assumptions.

RESULTS: Ribociclib reduced monthly direct medical costs associated with the administration of breast cancer treatment and the management of adverse events. Direct drug acquisition costs per month of ribociclib were in the range of the cost of current available and used therapies. Indirect treatment comparisons did not show statistical significance of the benefit of ribociclib vs. standard of care, primarily due to heterogeneity leading to a mixed evaluation vs. two comparator groups according to the statistical significance of the survival improvement.

Ribociclib is a 100% oral therapy with a manageable safety profile with dosage adjustments, so it does not require institutional resources for its administration or for managing adverse events. Its consolidated cost at 28 days of treatment is up to 40% less than combined chemotherapy regimens and up to 30% less than monotherapy schemes.

Average cost-effectiveness for progression-free survival for ribociclib is among the lowest considering chemotherapy options even though generic versions are available for many of them. For the comparators with comparable efficacy, ribociclib was cost-saving at current public market prices. For the comparators where ribociclib showed a significant benefit, the incremental cost-effectiveness ratio of ribociclib vs. standard of care is also below the threshold of 3 GDPs per capita vs. most options, leading to cost-effectiveness. A longer treatment duration due to progression delay was a main driver of incremental cost.

CONCLUSIONS: Ribociclib is cost-saving or cost-effective vs. standard of care in the Public Health System in Mexico. Other variables must be considered to inform clinical and funding decisions, such as disease burden and humanistic impact on this young, economically active population.

Citation Format: Saúl Campos-Gomez, Christian Pichardo Piña. Cost-effectiveness analysis of ribociclib in the treatment for premenopausal or perimenopausal women with HR+/HER2− advanced breast cancer: a public health care system perspective in Mexico [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO4-10-06.