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Introduction: In the United States, a total of 268,490 men were found to have prostate cancer in 2022, thus making it the most common cancer in men, accounting for 27% of all cancers in the male population. Among all cancers in men, it was the fifth leading cause of death, with 34,500 deaths and a mortality rate of 11%. In 2019, the total number of cases was 94,748, making it the leading cancer in males, accounting for 11% of all male cancers. In terms of mortality, it ranked seventh, with 13,217 deaths and a mortality rate of 1.6%. However, new treatment options for metastatic castration-sensitive prostate cancer (mCSPC) have emerged. Docetaxel has been shown to be effective for both mCSPC and castration-resistant prostate cancer (CRPC). Upfront docetaxel has not been approved in Japan, nor has it been validated in large-scale studies. Furthermore, several agents can be used after docetaxel treatment, but it is unclear which is the most effective. We used a large Japanese health insurance database to determine which agent would be the most effective as a next-line therapy in patients who had received docetaxel. Materials and Methods: We used data from medical institutions using the Diagnosis Procedure Combination (DPC), which provides a comprehensive evaluation of medical classifications. The Medical Data Vision database covers approximately 23% of DPC hospitals in Japan. This study analyzed 2938 patients with mCSPC who received docetaxel, followed by CRPC, between April 2008 and December 2021. The study focused on three agents: enzalutamide, abiraterone acetate, and cabazitaxel. Other agents were excluded due to the small number of patients. The following data were analyzed: age, date of CRPC diagnosis, presence of bone metastasis, drug type, and prognosis. Results: This study included 1997 patients with CRPC after upfront docetaxel therapy for mCSPC (enzalutamide [ENZ] group, n = 998; abiraterone acetate [ABI] group, n = 617; and cabazitaxel [CBZ] group, n = 382). The overall survival (OS) time from drug initiation was 456 days in the enzalutamide group, which was significantly longer than that in the cabazitaxel group (p = 0.017, HR 0.94) (ENZ: ABI p = 0.54, HR 0.94; ABI: CBZ p = 0.14, HR 0.75). OS was also compared for the third-line drug in the group that received enzalutamide as the second-line drug, the group that used abiraterone acetate as the third-line drug (ENZ-ABI group), and the group that used abiraterone acetate as the second-line drug. OS from the start of the third-line drug was compared between the ENZ–ABI group and the ABI–ENZ group, which received enzalutamide as the third-line drug, but showed no significant difference (269 vs. 281 days, p = 0.85; HR 1.03). Conclusion: ENZ was shown to prolong OS relative to cabazitaxel after the cessation of docetaxel. ENZ was associated with a longer duration of drug use than ABI and CBZ. [ABSTRACT FROM AUTHOR]

The final analysis of the phase 3 Targeted Investigational Treatment Analysis of Novel Anti-androgen (TITAN) trial showed improvement in overall survival (OS) and other efficacy endpoints with apalutamide plus androgen deprivation therapy (ADT) versus ADT alone in patients with metastatic castration-sensitive prostate cancer (mCSPC). As ethnicity and regional differences may affect treatment outcomes in advanced prostate cancer, a post hoc final analysis was conducted to assess the efficacy and safety of apalutamide in the Asian subpopulation. Event-driven endpoints were OS, and time from randomization to initiation of castration resistance, prostate-specific antigen (PSA) progression, and second progression-free survival (PFS2) on first subsequent therapy or death. Efficacy endpoints were assessed using the Kaplan–Meier method and Cox proportional-hazards models without formal statistical testing and adjustment for multiplicity. Participating Asian patients received once-daily apalutamide 240 mg (n = 111) or placebo (n = 110) plus ADT. After a median follow-up of 42.5 months and despite crossover of 47 placebo recipients to open-label apalutamide, apalutamide reduced the risk of death by 32% (hazard ratio [HR]: 0.68; 95% confidence interval [CI]: 0.42–1.13), risk of castration resistance by 69% (HR: 0.31; 95% CI: 0.21–0.46), PSA progression by 79% (HR: 0.21; 95% CI: 0.13–0.35) and PFS2 by 24% (HR: 0.76; 95% CI: 0.44–1.29) relative to placebo. The outcomes were comparable between subgroups with low- and high-volume disease at baseline. No new safety issues were identified. Apalutamide provides valuable clinical benefits to Asian patients with mCSPC, with an efficacy and safety profile consistent with that in the overall patient population. [ABSTRACT FROM AUTHOR]

Background: Metastatic castration‐resistant prostate cancer (mCRPC) is a genetically heterogeneous disease with a poor prognosis. The prevalence of mutations in homologous recombination repair (HRR) pathway genes, including BRCA1/2, as well as treatment patterns and clinical outcomes, are not well characterized among Japanese men with mCRPC. Methods: This multicenter, noninterventional cohort study enrolled Japanese men with mCRPC from 24 institutions between 2014 and 2018. Mutations in the 15 HRR‐related genes were assessed using archival primary or metastatic tumor samples. Patterns of sequential therapies for mCRPC were investigated. Patients were followed up for survival evaluation including prostate‐specific antigen progression‐free survival (PSA‐PFS) and overall survival (OS). Results: Of the 143 patients analyzed, HRR‐related mutations were detected in 51 patients (35.7%). The most frequently mutated genes were CDK12 (N = 19, 13.3%), followed by BRCA2 (N = 18, 12.6%), ATM (N = 8, 5.6%), and CHEK2 (N = 3, 2.1%). The most common type of first‐line therapy for mCRPC was next‐generation hormonal agents (NHA, 44.4%), followed by first‐generation antiandrogens (FGA, 30.3%), and taxanes (22.5%). Commonly prescribed first−/second‐line sequential regimens included FGA/NHA (17.6%), NHA/NHA (15.5%), and NHA/taxanes (14.1%). The median PSA‐PFS and OS for the entire cohort were 5.6 and 26.1 months, respectively. Patients carrying BRCA1/2 mutations had numerically shorter PSA‐PFS (median 3.3 vs. 5.9 months) and OS (median 20.7 vs. 27.3 months) than those without mutations. Conclusions: In conclusion, approximately one‐third of Japanese patients with mCRPC carried mutations in HRR‐related genes in this study. The real‐world outcomes of mCRPC are poor with conventional therapy, warranting an expansion of treatment options based on genetic abnormalities of the disease. [ABSTRACT FROM AUTHOR]