Population-Level Impact of T-DM1 Use for HER2-Positive Early Breast Cancer According to National Clinical Practice Guidelines in Sweden
Author(s)
Gustav Lanne, MSc1, Melina Arnold, MSc, PhD2, Svenn Alexander Kommandantvold, MASc, MPhil2, Carl-Henrik Shah, PhD, MD1.
1Roche AB, Solna, Sweden, 2Roche Products Ltd, Basel, Switzerland.
1Roche AB, Solna, Sweden, 2Roche Products Ltd, Basel, Switzerland.
OBJECTIVES: Treating early breast cancer (eBC) can prevent or delay the onset of recurrent metastatic disease. Trastuzumab emtansine (T-DM1) has demonstrated reduced disease recurrence compared to trastuzumab in patients with HER2+ eBC and residual disease following completion of neoadjuvant HER2-targeted therapy and surgery. Since 2020, National Clinical Practice Guidelines (NCPG) for HER2-positive eBC in Sweden recommend that all eligible patients receive T-DM1 in the adjuvant setting. The objective of this study is to quantify the population-level impact of increased T-DM1 use on averted metastatic recurrence and associated costs in patients with HER2-positive eBC in Sweden over the coming decade.
METHODS: A multi-year epidemiologic model was used to estimate the number of recurrences, costs, and quality-adjusted life years (QALYs). Incidence and population data were obtained from the Swedish National Registry for Breast Cancer (NKBC) and Statistics Sweden, respectively. Treatment rates were sourced from NKBC and other Swedish registries. Two scenarios were compared: base, steady-state uptake of therapeutic agents, and increased uptake, where treatment is in alignment with NCPG. In the latter scenario, all eligible patients receive T-DM1. Clinical efficacy data for T-DM1 were sourced from the KATHERINE trial and extrapolated over a 10-year time horizon. Country-specific cost inputs were sourced from the literature.
RESULTS: The model predicted that, over 2025-2034, 1,289 patients would receive T-DM1 in the adjuvant setting under a steady-state uptake scenario, compared to 4,075 patients in a scenario with increased uptake of T-DM1. Compared with the steady-state scenario, in the increased uptake scenario an additional 342 metastatic recurrences would be averted, yielding healthcare savings of 123 mSEK, productivity gains of 282 mSEK, and informal care cost savings of 20 mSEK. The increased uptake would result in a gain of 9,747 life years.
CONCLUSIONS: Increased T-DM1 use following NCPG would yield substantial population-level clinical and societal value in Sweden.
METHODS: A multi-year epidemiologic model was used to estimate the number of recurrences, costs, and quality-adjusted life years (QALYs). Incidence and population data were obtained from the Swedish National Registry for Breast Cancer (NKBC) and Statistics Sweden, respectively. Treatment rates were sourced from NKBC and other Swedish registries. Two scenarios were compared: base, steady-state uptake of therapeutic agents, and increased uptake, where treatment is in alignment with NCPG. In the latter scenario, all eligible patients receive T-DM1. Clinical efficacy data for T-DM1 were sourced from the KATHERINE trial and extrapolated over a 10-year time horizon. Country-specific cost inputs were sourced from the literature.
RESULTS: The model predicted that, over 2025-2034, 1,289 patients would receive T-DM1 in the adjuvant setting under a steady-state uptake scenario, compared to 4,075 patients in a scenario with increased uptake of T-DM1. Compared with the steady-state scenario, in the increased uptake scenario an additional 342 metastatic recurrences would be averted, yielding healthcare savings of 123 mSEK, productivity gains of 282 mSEK, and informal care cost savings of 20 mSEK. The increased uptake would result in a gain of 9,747 life years.
CONCLUSIONS: Increased T-DM1 use following NCPG would yield substantial population-level clinical and societal value in Sweden.
Conference/Value in Health Info
2025-11, ISPOR Europe 2025, Glasgow, Scotland
Value in Health, Volume 28, Issue S2
Code
EPH182
Topic
Epidemiology & Public Health
Topic Subcategory
Public Health
Disease
Oncology