Clinical Outcomes of Patients with High-risk Metastatic Hormone-naïve Prostate Cancer: A 3-year Interim Analysis of the Observational J-ROCK Study.

BACKGROUND: Androgen deprivation therapy (ADT), administered alone, as combined androgen blockade (CAB) or as ADT plus androgen receptor signalling inhibitors (ARSIs) or ADT plus docetaxel, is the standard treatment for metastatic hormone-naïve prostate cancer (mHNPC) in Japanese real-world practice. OBJECTIVE: To investigate treatment patterns and clinical outcomes in LATITUDE criteria high-risk mHNPC. DESIGN, SETTING, AND PARTICIPANTS: The longitudinal, multicentre, J-ROCK registry study enrolled patients initiating ADT in Japan after May 2019, and categorised them as cohort 1 (ADT or CAB) or cohort 2 (ADT plus ARSIs or docetaxel). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Prostate-specific antigen (PSA) response, progression-free survival (PFS), time to castrate-resistant prostate cancer (CRPC), overall survival (OS), and safety were evaluated. PFS, time to CRPC, and OS were estimated via the Kaplan-Meier method and between-cohort comparisons via multivariate Cox regression models. RESULTS AND LIMITATIONS: In total, 974 patients were included (cohort 1: 38.1%, cohort 2: 61.9%). CAB was preferred (67.4%) to ADT alone in cohort 1, and abiraterone acetate plus prednisolone was used most frequently in cohort 2 (59.4%). The proportion of patients with ≥50%/≥90% PSA decline or who achieved PSA ≤0.2/≤0.1 ng/ml tended to be higher in cohort 2. PFS (adjusted hazard ratio 0.42; 95% confidence interval [CI] 0.31-0.55), time to CRPC (0.28; 95% CI 0.23-0.36), and OS (0.54; 95% CI 0.35-0.82) were longer in cohort 2. In cohorts 1 and 2, adverse drug reactions of special interest (ADRSIs) occurred in 1.3% and 15.1%, and fatal adverse events occurred in 1.9% and 1.7%, respectively. Limitations included nonrandomised design, varying time since marketing authorisation for ARSIs, and limited safety assessments. CONCLUSIONS: ADT plus ARSIs or docetaxel was used more frequently to treat high-risk mHNPC than standard ADT/CAB and was associated with more favourable clinical outcomes. Although ADRSIs were reported more in cohort 2, the safety profile was considered tolerable. PATIENT SUMMARY: Although many treatment options are available for high-risk metastatic prostate cancer, there are limited reports on real-world clinical experience with different therapies outside of the clinical trial setting. In this study, we compared clinical and safety outcomes with different treatment regimens, using a large series of patients with high-risk metastatic hormone-naïve prostate cancer across Japan. We found that androgen deprivation therapy in combination with newer androgen receptor signalling inhibitors resulted in improved response compared with androgen deprivation therapy alone or in combination with a first-generation antiandrogen.

Treatment strategies and outcomes in a long-term registry study of patients with high-risk metastatic hormone-naïve prostate cancer in Japan: An interim analysis of the J-ROCK study.

OBJECTIVE: The prognosis of high-risk metastatic hormone-naïve prostate cancer is poor, and real-world evidence of therapeutic options and sequences is lacking. The J-ROCK study aimed to evaluate the outcomes in a real-world setting in Japan. METHODS: Patients with high-risk metastatic hormone-naïve prostate cancer diagnosed after May 2019 were eligible. Based on their treatment within 3 months after diagnosis, patients were allocated to either cohort 1 (androgen deprivation therapy alone or combined androgen blockade with bicalutamide) or cohort 2 (androgen deprivation therapy with abiraterone acetate+prednisolone, docetaxel, enzalutamide, or apalutamide). RESULTS: In this first interim analysis (cut-off January 2021), 410 patients were enrolled, including 163 patients in cohort 1 and 247 in cohort 2. The median follow-up period was 7.6 (range 0.1-20.5) months. A higher proportion of patients in cohort 2 (42.5%) achieved nadir prostate-specific antigen levels ≤0.2 ng/ml within a year, compared with cohort 1 (22.1%). Prostate-specific antigen-progression-free survival was also more favorable in cohort 2 (adjusted hazard ratio 0.629 [95% confidence interval 0.345-1.147]). CONCLUSIONS: The higher proportion of cohort 2 suggest a paradigm shift has occurred in the real-world treatment of high-risk metastatic hormone-naïve prostate cancer in Japan. Some factors including prostate-specific antigen may affect treatment selection but need further observation. Most patients in cohort 2 received abiraterone acetate+prednisolone. The proportion of patients in cohort 1 receiving combined androgen blockade was lower than previously reported in Japan. This analysis suggest that more intensive therapy tends to prolong prostate-specific antigen-progression-free survival in patients with high-risk metastatic hormone-naïve prostate cancer.

Safety and efficacy of apalutamide in Japanese patients with metastatic castration-sensitive prostate cancer receiving androgen deprivation therapy: Final report for the Japanese subpopulation analysis of the randomized, placebo-controlled, phase III TITAN study.

OBJECTIVES: The TITAN study is a randomized, double-blind, placebo-controlled, multinational trial that evaluated apalutamide with androgen deprivation therapy in patients with metastatic castration-sensitive prostate cancer. At the first interim analysis in the Japanese subpopulation (median follow-up 25.7 months), there was an improvement in overall survival and radiological progression-free survival with apalutamide versus placebo. Here, we report the final analysis results for the Japanese subpopulation. METHODS: Patients were randomized 1:1 to receive apalutamide 240 mg or placebo. After the first interim analysis, protocol treatment was unblinded, and crossover was allowed. Efficacy and safety were evaluated in the preplanned, event-driven final analysis. RESULTS: Fifty-one patients were Japanese (apalutamide n = 28; placebo n = 23). After a median follow-up of 46.0 months, the median overall survival was not reached neither in the apalutamide nor the placebo group; the hazard ratio was 0.45, favoring apalutamide, which was consistent with the overall population. Hazard ratios for time to cytotoxic chemotherapy (0.39), time to pain progression (0.87), and time to chronic opioid use (0.82) also favored apalutamide and were comparable with those of the overall population. Time to prostate-specific antigen progression and progression-free survival 2, respectively, was favored in the apalutamide group (0.21 and 0.44). Apalutamide was associated with higher incidences of rash and fracture in the Japanese subpopulation compared with the overall population. CONCLUSIONS: The efficacy of apalutamide with androgen deprivation therapy in Japanese patients was consistent with efficacy demonstrated in the overall population. No new safety concerns emerged with long-term follow-up.

Effects of sediment influx on the settlement and survival of canopy-forming macrophytes.

Kelp forests on coastal rocky shores are negatively impacted by sudden sediment loads that can occur with storms and floods. Using laboratory experiments, we studied the effects of sediment deposition on the survival of the large brown alga Eisenia bicyclis juveniles (zoospores and gametophytes) to quantify the potential impacts of particulate matter on kelp forests. The zoospore adhesion rate and the gametophyte survival and growth rates all declined markedly with increasing sediment load, particularly with smaller particle diameter. Using experimental results, we derived an equation to calculate the rate of initial kelp depletion with sediment load based on the quantity and size distribution of sediment particles. The equation enabled the estimation of E. bicyclis depletion rates in the field by measurement of particle quantity and diameter distribution of sediments on the reef substrate.