ARASENS was a randomized, double-blind, phase 3 trial comparing darolutamide + docetaxel + androgen deprivation therapy (ADT) with placebo + docetaxel + ADT in patients with metastatic hormone-sensitive prostate cancer (mHSPC). To use clinical trial data from ARASENS to understand whether the addition of darolutamide to docetaxel + ADT leads to increased hospitalizations and to estimate the budget impact on the US health care system. We used mixed-effects negative binomial regression to estimate hospitalization and intensive care unit (ICU) admission rates and length of hospital stay (LoHS) counts. Hospitalization rates were estimated per treatment arm for the period during and after administration of docetaxel. Based on these estimates, a budget impact analysis evaluated the hospitalization costs (including ICU admissions) and standalone ICU hospitalization costs for the totality of the US population over a 5-year time horizon. The analysis compared a scenario without darolutamide vs one with darolutamide included in the US payer formulary. Hospitalization estimates were varied in a one-way sensitivity analysis. The first 4 months of treatment (when patients were receiving docetaxel) were associated with increased hospitalizations across both arms. The addition of darolutamide was associated with a numerical reduction in the rate of hospitalization (per year) due to any reason both during docetaxel treatment (1.01 visits per year [95% CI = 0.82-1.20] vs 1.18 visits per year [95% CI = 0.96-1.41]) and after docetaxel treatment (0.28 visits per year [95% CI = 0.23-0.34] vs 0.33 visits per year [95% CI = 0.27-0.40]). Darolutamide was associated with a marginally longer LoHS per hospitalization compared with placebo (+1.90 days per year) both during and after docetaxel treatment. ICU admissions were low in the ARASENS data; admission rates were assumed to be the same during and after docetaxel treatment. ICU admission rate estimates were equivalent across arms (0.02 visits per year [95% CI = 0.01-0.03]). The budget impact per treated member per month represents a cost-neutral option after Year 5 with a cumulative budget impact of -$9.71. The addition of darolutamide to docetaxel + ADT was associated with a numerically lower rate of hospitalization but marginally longer LoHS compared with docetaxel + ADT alone. Darolutamide represents a cost-neutral alternative per treated member per month compared with docetaxel + ADT with regard to hospitalizations at the end of a 5-year time horizon.