Failure to reach study enrollment milestones

Investigators propose a double-blind, placebo-controlled trial evaluating the use of the use of Suvorexant in breast cancer survivors on selective estrogen receptor modulators or aromatase inhibitors with sleep disturbance to assess the impact on insomnia symptoms and quality of life. Breast cancer survivors have an increased risk of insomnia for which Suvorexant has the has the potential ability to impact to improve sleep related outcomes and cancer survivorship outcomes. Breast cancer survivors with sleep disturbance based on an Insomnia Severity Index Score (ISI) >15 will be randomized to either Suvorexant or placebo, with both arms receiving education on sleep hygiene.

Cancer survivors have an incidence of sleep disturbance and insomnia higher than the general population, with significant potential implications on health outcomes including in survivorship domains and mortality outcomes. Available pharmacologic options for management of sleep disturbance are limited in efficacy and in their side effects. Investigators propose a double-blind placebo-controlled trial evaluating the use of the use of Suvorexant in breast cancer survivors on selective estrogen receptor modulators or aromatase inhibitors with sleep disturbance to assess the impact on insomnia symptoms and quality of life. Evaluation of breast cancer survivors on endocrine therapy uses a study population with high 5-year survival rate while retaining the capacity for recruitment and creating an opportunity to explore potential effects on vasomotor symptoms. Suvorexant has the potential to have a significant impact in cancer survivors not only on sleep related outcomes but also on cancer survivorship outcomes.

The purpose of the research study is to evaluate the ability of Suvorexant, a medication approved by the Food and Drug Administration (FDA) for insomnia, to treat sleep disturbance in breast cancer survivors on endocrine therapy.

Inclusion Criteria:

• Adult post menopausal breast cancer survivors (female, > 18 years old)
• current selective estrogen modulator or aromatase inhibitor use
• at least 6 weeks beyond completion of definitive treatment for breast cancer
• less than 5 years from time of diagnosis.

Exclusion Criteria:

• less than 6-month life expectancy
• current steroid use
• severe depression or anxiety
• severe hepatic impairment
• concurrent use of moderate or strong CYP3A inhibitors
• current receipt of hospice care
• severe mental illness
• current use of greater than 40 morphine milligram equivalents daily
• diagnosis of obstructive sleep apnea, narcolepsy or other sleep related illness other than insomnia
• pregnancy
• treatment with alternate pharmacotherapy for insomnia at the time of trial initiation
• menstrual cycle within the past year

Adult women with history of breast cancer on a selective estrogen modulators or aromatase inhibitors with symptoms of insomnia as characterized by an ISI score of 15 or more will be included in the study population.