Treatment patterns in women with breast cancer and endocrine therapy-related menopausal symptoms: a cohort study from the United States, United Kingdom, and Germany.

Objective: To describe treatment patterns for menopausal symptoms in women taking endocrine therapy for breast cancer treatment/prevention from the United States (US), United Kingdom (UK), and Germany.

Methods: We undertook a retrospective cohort study using data from the US Market Scan Commercial Claims and Encounters Data database, and electronic health records from the UK's Clinical Practice Research Database Aurum and the German Disease Analyzer. Women aged 18-65 years with a first prescription/dispensation for endocrine therapy for breast cancer treatment or prevention (index date) from 2010 to 2022 were followed up, and the following treatment classes were evaluated: antidepressants, benzodiazepines, anticonvulsants, antihypertensives, and hormone therapy.

Results: Treatments were recorded in 32.7% (39,137/119,717) US women, 20.4% (8,350/40,956) UK women, and 8.3% (1,031/12,388) German women. Among these, ~80% in the US and UK, and all in Germany, received one treatment class; switches occurred in 20.5% (US) and 16.5% (UK). The most frequent initial treatment classes were antidepressants (31.7% US, 45.3% UK, 38.1% Germany); the second most frequent were benzodiazepines (30.3% US), anticonvulsants (24.3% UK), and hormone therapy (27.2% Germany). Among antidepressants, the most common were venlafaxine (US and Germany), and amitriptyline, sertraline, and citalopram (UK). Six-month continuation rates for antidepressants were 42% (US), 12% (UK), and 7% (Germany); continuation rates for other treatments were even lower.

Conclusions: Continuation rates with available treatments for menopausal symptoms in women receiving endocrine therapy for breast cancer treatment/prevention are very low. This indicates a clear unmet need for safe, effective, and well-tolerated treatments in this patient population.