Health-related Quality of Life at the SPARTAN Final Analysis of Apalutamide for Nonmetastatic Castration-resistant Prostate Cancer Patients Receiving Androgen Deprivation Therapy

Background: In SPARTAN, apalutamide improved metastasis-free and overall survival for patients with nonmetastatic castration-resistant prostate cancer (nmCRPC) with a prostate-specific antigen doubling time of ≤10 mo. Objective: We evaluated health-related quality of life (HRQoL) at the final analysis of the SPARTAN study. Intervention: Patients received apalutamide (240 mg/d) or placebo in 28-d cycles. All patients continued androgen deprivation therapy (ADT). Design, setting, and participants: A total of 1207 patients with nmCRPC were randomized 2:1 to apalutamide or placebo. Outcome measurements and statistical analysis: HRQoL was assessed using Functional Assessment of Cancer Therapy-Prostate (FACT-P) and EQ-5D-3L questionnaires at day 1 of cycle 1 (predose/baseline), cycles 2–6, every two cycles during cycles 7–13, every four cycles thereafter, at the end of treatment, and every 4 mo after progression to 1 yr. Results are presented using descriptive statistics. A mixed model for repeated measures was fitted to estimate the mean scores at each scheduled visit during treatment. Results: At final analysis, with 52 mo follow-up for survival, the median treatment duration was 32.9 mo for apalutamide and 11.5 mo for placebo. Patients had good baseline HRQoL. At each scheduled collection during treatment, >90% per group completed the questionnaires. The change in FACT-P total score from baseline to cycles 21 and 25 significantly favored apalutamide over placebo (p = 0.0138 and 0.0009, respectively). The apalutamide group generally maintained favorable FACT-P (total and subscales) and EQ-5D-3L scores, while placebo scores tended to decline over time (starting in cycles 11–13 and pronounced by cycles 21–25). Notably, patient-reported fatigue did not worsen with apalutamide. Most patients reported being “not at all bothered” by side effects, and bother did not increase over time with apalutamide or placebo. Patients receiving apalutamide had minimal change in side-effect bother following symptomatic adverse events. Conclusions: Final analysis of SPARTAN confirms that HRQoL is preserved in patients with nmCRPC receiving apalutamide plus ADT, but declines in patients receiving placebo plus ADT after approximately 1 yr. Patient summary: Responses from patients with prostate cancer who were included in the SPARTAN study indicated that treatment with apalutamide, even after the most extensive follow-up time possible, did not reduce their quality of life. These results, along with improved survival and longer time to the development of metastases (reported separately), confirm the benefits of apalutamide for patients with nonmetastatic castration-resistant prostate cancer.