UNLABELLED: focused on patients living with metastatic cancer. We examined the feasibility of the SleepNow intervention combining cognitive behavioral therapy for insomnia (CBT-I) with physical exercise in men with metastatic prostate cancer (mPCa). PATIENTS/MATERIAL AND METHODS: We conducted a feasibility randomized trial in patients under treatment for castration resistant mPCa with insomnia (Insomnia Severity Index [ISI] score ≥ 8). Patients were randomized 1:1 to either SleepNow or usual care. SleepNow is a manualized 12-week program consisting of bi-weekly sessions of physical exercise and four nurse-led sessions of CBT-I. Patients in usual care received no insomnia treatment. We assessed feasibility and measured objective and patient-reported outcomes at baseline and 3-months follow-up. Changes in both groups were compared using the Wilcoxon test. RESULTS: We randomized 12 patients (5 intervention and 7 control
age range = 59-81 years, mean Gleason score = 7.75, mean time since diagnosis ≈ 7 years). Intervention patients reported high satisfaction, all attended at least three CBT-I sessions (75%) and four completed at least 20 of the 24 training sessions. The intervention group showed improvements in insomnia, sleep quality, fatigue, anxiety, depression and health-related quality-of-life but between-group differences were not statistically significant. INTERPRETATION: The SleepNow intervention is the first to combine nurse-delivered CBT-I and physical exercise and was acceptable and potentially efficacious. Our results are important for targeting sleep interventions to the growing population of patients living long term with metastatic cancer.