Treatment patterns and outcomes in patients with nonmetastatic castration-resistant prostate cancer in the United States.

Aim: Androgen receptor pathway inhibitors (ARPIs) prolong metastasis-free survival and overall survival in patients with nonmetastatic castration-resistant prostate cancer (nmCRPC). This study aimed to evaluate real-world treatment patterns, utilization and survival outcomes in patients with nmCRPC. Patients & methods: This retrospective cohort study used Optum database electronic health records of patients with nmCRPC from 1 January 2007 to 31 December 2020 in the US. Results: Of 1955 patients, >80% received androgen-deprivation therapy (ADT) alone or ADT + first-generation nonsteroidal antiandrogen (NSAA) as first-line treatment, while only 8.24% received ADT + ARPI. ADT + ARPI remained underutilized even among those with high-risk nmCRPC. Further, ADT + NSAA had no survival benefit compared with ADT alone. Conclusion: Practice-improvement strategies are needed for treatment intensification with ARPIs for patients with nmCRPC. Plain Language Summary Prostate cancer cells often use hormones called androgens to grow and survive. Hormone therapy is a treatment that lowers the amount of these hormones in the body to slow down the cancer's growth. It includes androgen-deprivation therapy (ADT), which can either be used alone or along with nonsteroidal antiandrogens (NSAAs) or with androgen receptor pathway inhibitors (ARPIs). Nonmetastatic castration-resistant prostate cancer (nmCRPC) is defined as prostate cancer that has not spread to other parts of the body but exhibits rising levels of serum prostate-specific antigen despite surgery or ADT to reduce androgens. Research shows that ARPIs can improve survival in patients with nmCRPC, but more data on its use are needed. This study looked at the electronic health records of patients with nmCRPC to review the treatment they had received and their survival. Between 2008 and 2020, most patients received ADT alone or with NSAA. Even though the number of patients receiving ADT with ARPI increased during this period, it remained underused, even in patients with a high risk of cancer spreading to other body parts. Post-2018, even after 2 years of these drugs being available, only about one in five patients received ADT with ARPI. Also, people who received ADT with NSAA did not have a longer survival than patients treated with ADT alone. The study indicates that ARPIs, which could improve survival of patients with nmCRPC, are not being utilized optimally. Strategies that promote early use of ARPIs are needed to improve survival of patients with nmCRPC. In this retrospective observational cohort study, treatment patterns and survival outcomes of patients with nonmetastatic castration-resistant prostate cancer (nmCRPC) were investigated using electronic health records from the Optum clinical database. During the study period between 1 January 2007 and 31 December 2020, patients with nmCRPC defined on the basis of recorded prostate-specific antigen (PSA) values after surgical or medical castration were identified as per the inclusion and exclusion criteria. First-line (1L) regimens included ADT alone, ADT + NSAA ± glucocorticoids (ADT + NSAA), ADT + ARPI ± glucocorticoids ± NSAA (ADT + ARPI) and "other," which included all remaining regimens. Between 2008 and 2020, most patients (>80%) were treated with ADT alone or ADT + NSAA as 1L treatment, and only 8% received ADT + ARPIs, suggesting that despite ARPIs having been approved and included in treatment guidelines, they remain underutilized, even in patients at a high risk of metastasis (PSADT ≤10 months or Gleason score ≥8). Approximately, 55% of patients with nmCRPC developed metastasis during follow-up, and 70% received a new regimen (metastatic 1L treatment); ADT + ARPI was the common metastatic 1L treatment (42%), 2L (44%) and 3L (36.5%) mCRPC regimen. Time to death was shorter in the ADT + NSAA cohort (median OS: 30.87 months, 95% CI: 28.2–35.73) than the ADT-alone cohort (median OS: 41.70, 95% CI: 37.63–45.60) with statistical significance (HR: 1.33, 95% CI: 1.16–1.52), suggesting that despite ADT + NSAA appearing to be associated with worse clinical outcomes than ADT alone, it still had higher utilization than ADT + ARPI. Healthcare professionals should recognize the limited efficacy of NSAA and consider using ARPIs to treat patients with severe disease. Practice-improvement strategies are needed to ensure early treatment with ARPIs in patients with nmCRPC. [ABSTRACT FROM AUTHOR]