OBJECTIVES: To estimate societal costs due to work productivity loss and activity impairment with ribociclib + ET compared with ET alone among premenopausal women with HR+/HER2− ABC from a US perspective.

METHODS: Work Productivity and Activity Impairment: General Health (WPAI:GH) data from 672 patients in the MONALEESA-7 trial were analysed (data cutoff, November 30, 2018). For patients receiving either ribociclib + ET or ET alone, societal costs were derived for progression-free disease, progressed disease, and early mortality, defined by treatment-specific estimates of median progression-free survival (PFS) and median overall survival (OS), using a human capital approach. Mixed-model repeated measures were used to estimate monthly work productivity loss and health-related unemployment (paid work) and activity impairment (unpaid work) up to the national retirement age (66 years). Costs are reported in US dollars ($) and discounted at 3% annually.

RESULTS: From treatment initiation (mean age, 43.15 years) to the national retirement age (66 years), an average premenopausal patient with ABC receiving ribociclib + ET had $33,092 lower societal costs due to work productivity loss, health-related unemployment, and activity impairment compared with ET alone. Societal costs for the average ribociclib + ET patient were $453,625 for paid work (including disease-related unemployment) and $247,244 for unpaid work, compared with $468,649 and $265,313 for ET alone, respectively. For an estimated 11,769 annual new cases of premenopausal HR+/HER2− ABC (SEER data), ribociclib + ET would potentially yield $389.45 million lower societal costs than ET alone.

CONCLUSIONS: Ribociclib + ET is associated with lower societal costs in both paid and unpaid work for HR+/HER2− patients with ABC compared with ET alone, largely driven by differences in health-related unemployment and activity impairment. This is attributed to the statistically significant prolongation of median PFS and OS observed with ribociclib + ET compared with ET alone in the MONALEESA-7 trial.