Prostate-specific Antigen Nadir and Cancer-Control Outcomes in Real-world Apalutamide-treated Metastatic Hormone-Sensitive Prostate Cancer Patients: A Single-Center Analysis.

Currently available post hoc phase 3 trial-derived data suggest better cancer-control outcomes in apalutamide-treated metastatic hormone-sensitive prostate cancer (mHSPC) patients achieving an (ultra)low prostate-specific antigen (PSA) nadir. This study aims to validate ultralow PSA nadir cutoffs. Relying on an institutional prostate cancer database, 107 eligible patients were yielded. The currently available PSA nadir cutoffs (SWOG trial: <0.2 ng/ml; ultralow TITAN trial: ≤0.02 vs 0.02-0.2 vs >0.2 ng/ml) and PSA responses (≥99%) were tested for time to castration-resistant prostate cancer (ttCRPC) and overall survival (OS) in mHSPC patients treated with apalutamide. Finally, comparisons were made against abiraterone mHSPC treatment. Overall, 107 mHSPC patients treated with apalutamide at a median age of 68 yr and baseline PSA of 29 ng/ml were included. The highest proportion of included patients (40.2%) achieved an ultralow PSA nadir of ≤0.02 ng/ml. Patients reaching the SWOG 9346-defined PSA nadir of <0.2 ng/ml and ultralow PSA nadir of ≤0.02 ng/ml harbored the longest time to metastatic castration-resistant prostate cancer (mCRPC) and OS (all p < 0.05). Moreover, 80% of mHSPC patients treated with apalutamide achieved a PSA response of ≥99%. These patients also harbored better time to mCRPC and OS outcomes, relative to patients with a <99% PSA response (both p < 0.05). In the second step of analyses, a comparison against abiraterone patients showed a significantly higher rate of achieving an ultralow PSA nadir of ≤0.02 ng/ml: 40.2% versus 8.8% for apalutamide versus abiraterone, resulting in a significantly longer ttCRPC for the apalutamide-treated (37 mo) than for the abiraterone-treated (22 mo) group (p = 0.001), even after multivariable adjustment and in sensitivity analyses for high-risk mHSPC patients only. The study is limited by its retrospective design. In the real-world setting, most mHSPC patients treated with apalutamide achieve an ultralow PSA nadir, which is associated with better cancer-control outcomes. Moreover, a PSA response of ≥99% predicts better outcomes. In head-to-head comparisons, apalutamide achieves better PSA kinetics and ttCRPC outcomes than abiraterone. A prostate-specific antigen (PSA) nadir of <0.02 ng/ml and PSA responses ≥99% are associated with better cancer-control outcomes in metastatic hormone-sensitive prostate cancer patients treated with apalutamide.

Wenzel M ，Cano Garcia C ，Humke C ，Hoeh B ，Steuber T ，Tilki D ，Merseburger AS ，Kluth LA ，Chun FKH ，Mandel P ... -  《European Urology Oncology》

Comparative effectiveness of multiple androgen receptor signaling inhibitor medicines with androgen deprivation therapy for metastatic hormone-sensitive prostate cancer: a study in the real world.

The current treatment strategy for metastatic Hormone-Sensitive Prostate Cancer (mHSPC) is the combination of Androgen Receptor Signaling Inhibitors (ARSIs) medicines with androgen deprivation therapy (ADT). However, there is a lack of real-world data comparing the efficacy of different ARSI pharmaceuticals. Therefore, the objective of this study was to compare the effectiveness and safety of bicalutamide, abiraterone, enzalutamide, and apalutamide in combination with ADT for patients with mHSPC. We retrospectively analyzed 82 patients diagnosed with mHSPC, including 18 patients treated with abiraterone acetate with prednisone, 21 patients with enzalutamide, 20 patients with apalutamide, and 23 patients with bicalutamide. We evaluated PSA progression-free survival (PSA-PFS), imaging progression-free survival (r PFS), castration resistance progression-free survival (CRPC-PFS), and overall survival (OS) using Kaplan-Meier survival analyses. Additionally, we explored relevant factors affecting prognosis through univariate and multivariate Cox risk-proportionality models. PSA response rates at 3, 6, and 12 months, nadir PSA levels (nPSA), and time to nadir (TTN) in different medication subgroups after treatment were documented, and we used one-way ANOVA to determine the effect of these measures on patient prognosis. In comparison with bicalutamide, both enzalutamide and apalutamide have shown significant advantages in delaying disease progression among mHSPC patients. Specifically, enzalutamide has been found to significantly prolong PSA-PFS (HR 2.244; 95% CI 1.366-3.685, p=0.001), rPFS (HR 2.539; 95% CI 1.181-5.461; p= 0.007), CRPC-PFS (HR 2.131; 95% CI 1.295-3.506; p= 0.003), and OS (HR 2.06; 95% CI 1.183-3.585; P=0.005). Similarly, apalutamide has significantly extended PSA-PFS (HR 5.071; 95% CI 1.711-15.032; P= 0.003) and CRPC-PFS (HR 6.724; 95% CI 1.976-22.878; P=0.002) among patients. On the other hand, the use of abiraterone in combination with ADT did not demonstrate a significant advantage in delaying diseases progression when compared with the other three agents in mHSPC patients. There were no significant differences in overall adverse event rates among the four pharmaceuticals in terms of safety. Additionally, the observation of PSA kinetics revealed that enzalutamide, apalutamide, and abiraterone acetate had a significant advantage in achieving deep PSA response (PSA ≤ 0.2 ng/ml) compared with bicalutamide (p=0.007 at 12 months). Enzalutamide and apalutamide exhibited preeminence efficacy, with no substantial difference observed between the two medications. Abiraterone, enzalutamide, and apalutamide were found to significantly reduce and stabilize PSA levels in mHSPC patients more quickly and thoroughly than bicalutamide. Furthermore, enzalutamide and apalutamide were found to significantly prolong survival and delay disease progression in mHSPC patients compared with bicalutamide. It should be noted that abiraterone did not demonstrate a significant advantage in delaying disease compared with enzalutamide and apalutamide. After conducting drug toxicity analyses, it was determined that there were no significant differences among the four drugs.

Lu Y ，Jiang J ，Yang G ，Ding H ，Zheng Q ，Ji L ，Wang Y ，Dong Z ，Zhai Z ，Tian J ，Zhang Y ，Wang J ，Yang L ，Wang Z ... -  《Frontiers in Oncology》

Targeted Investigational Treatment Analysis of Novel Anti-androgen (TITAN) study: ultralow prostate-specific antigen decline with apalutamide plus androgen-deprivation therapy.

To assess the association between achievement of prostate-specific antigen (PSA) levels ≤0.2 ng/mL (henceforth 'ultralow') and clinical outcomes in patients in the 'Targeted Investigational Treatment Analysis of Novel Anti-androgen' (TITAN) study (ClinicalTrials.gov Identifier NCT02489318) with metastatic castration-sensitive prostate cancer (mCSPC). Patients in the TITAN study with mCSPC were randomised to 240 mg/day apalutamide (n = 525) or placebo (n = 527) plus androgen-deprivation therapy. This post hoc analysis assessed the achievement of a PSA level of 0.2->0.02 ng/mL ('ultralow one' [UL1]) and ≤0.02 ng/mL ('ultralow two' [UL2]) vs >0.2 ng/mL with apalutamide treatment and its association with radiographic progression-free survival (rPFS), overall survival (OS), time to castration-resistant PC (TTCRPC), and time to PSA progression (TTPP). The landmark analysis and Kaplan-Meier methods were used. By 3 months, more patients achieved UL1 and UL2 with apalutamide (38% and 23%) vs placebo (15% and 5%). In the apalutamide-treated patients, UL2 vs PSA >0.2 ng/mL at landmark 3 months was associated with significantly longer rPFS (hazard ratio [HR] 0.28, 95% confidence interval [CI] 0.14-0.54), OS (HR 0.24, 95% CI 0.13-0.43), TTCRPC (HR 0.2, 95% CI 0.11-0.38), and TTPP (HR 0.11, 95% CI 0.04-0.27; nominal P values all <0.001); this association was also observed but less pronounced for UL1. Similar findings were observed at 6 months. Early onset of decline to UL2 by 3 months was associated with improved survival vs PSA >0.2 ng/mL anytime (HR 0.12, 95% CI 0.06-0.22; P < 0.001) in apalutamide-treated patients. In this post hoc analysis of TITAN, patients with the deepest PSA decline derived the greatest benefit. These results extend our findings of apalutamide efficacy in the overall TITAN population, underscoring the clinical value of PSA kinetics as a marker for treatment efficacy. Patients with metastatic prostate cancer that is sensitive to ongoing hormonal treatment benefited significantly from the addition of apalutamide compared with placebo. Those who achieved rapid and deep PSA reduction had the greatest survival benefit.

Merseburger AS ，Agarwal N ，Bjartell A ，Uemura H ，Soto AJ ，Bhaumik A ，Böhm J ，Tran N ，Krochmann N ，Nematian-Samani M ，Mundle SD ，Brookman-May SD ，Lopez-Gitlitz A ，McCarthy SA ，Chi K ，Chowdhury S ... -  《-》

Impact of PSA nadir, PSA response and time to PSA nadir on overall survival in real-world setting of metastatic hormone-sensitive prostate cancer patients.

To evaluate the impact of prostate-specific antigen (PSA) nadir, PSA response and time to PSA nadir (TTN) in metastatic hormone-sensitive prostate cancer (mHSPC) patients on overall survival (OS) in the era of combination therapies. Different PSA nadir cut-offs (including ultra-low PSA) were tested for OS analyses. Additionally, PSA response ≥99% was evaluated, as well as TTN categorized as <3 versus 3-6 versus 6-12 versus >12 months. Multivariable Cox regression models predicted the value of PSA nadir cut-offs, PSA response and TTN on OS. Sensitivity analyses were performed in de novo and high volume mHSPC patients. Of 238 eligible patients, PSA cut-offs of <0.2 versus 0.2-4.0 versus >4.0 ng/mL differed significantly regarding median OS (96 vs. 56 vs. 44 months, p < 0.01), as well as in subgroup analyses of de novo mHSPC patients and multivariable Cox regression models. A more stringent PSA cut-off of <0.02 versus 0.02-0.2 versus >0.2 ng/mL also yielded significant median OS differences (not reached vs. 96 vs. 50 months, p < 0.01), even after additional multivariable adjustment. A PSA response ≥99% was also significantly associated with better OS than counterparty with <99% response, even after multivariable adjustment (both p < 0.02). When TTN groups were compared, patients with longer TTN harbored more extended OS than those with short TTN (<3 vs. 3-6 vs. 6-12 vs. >12 months: 34 vs. 50 vs. 67 vs. 96 months, p < 0.01). Virtually similar results were observed in sensitivity analyses for high volume mHSPC patients. In times of combination therapies for mHSPC, a PSA nadir of respectively, <0.2 and <0.02 ng/mL are associated with best OS rates. Moreover, a relative PSA response ≥99% and a longer TTN are clinical important proxies for favorable OS estimates.

Wenzel M ，Hoeh B ，Hurst F ，Koll F ，Cano Garcia C ，Humke C ，Steuber T ，Tilki D ，Traumann M ，Banek S ，Chun FKH ，Mandel P ... -  《-》

Comparison of abiraterone, enzalutamide, and apalutamide for metastatic hormone-sensitive prostate cancer: A multicenter study.

We aimed to assess the differential efficacy and safety of androgen receptor pathway inhibitors (ARPI), such as abiraterone, enzalutamide, and apalutamide, in patients with metastatic hormone-sensitive prostate cancer (mHSPC) in a real-world practice setting. We retrospectively reviewed the records of consequent 668 patients with mHSPC treated with ARPI plus androgen deprivation therapy between September 2015 and December 2023. Based on the LATITUDE criteria, the comparison among abiraterone, enzalutamide, and apalutamide was exclusively conducted in high-risk patients. Prostate-specific antigen (PSA) responses such as the achievement of 95% and 99% PSA decline, overall survival (OS), cancer-specific survival (CSS), time to castration-resistant prostate cancer (CRPC), and the incidence of adverse events (AEs) were compared. All two-group comparisons relied on propensity score matching (PSM) to minimize the effect on possible confounders. In total, 297 patients with high-risk mHSPC treated with abiraterone, 127 with enzalutamide, and 142 with apalutamide were compared. There were no differences in time to CRPC (p = 0.13), OS (p = 0.7), and CSS (p = 0.5) among the three ARPIs. No differences were observed in the achievement rates for 95% PSA decline at 3 months among the three ARPIs, while abiraterone was significantly better in 99% PSA decline achievement compared to apalutamide (72% vs. 57%, p = 0.003). The aforementioned oncologic outcomes were sustained even when performing PSM analyzes. Although skin rash for APA (34%) was the highest incidence of AEs, there were no differences in the rates of severe AEs across the three ARPIs. Enzalutamide resulted in the lowest treatment discontinuation rates (10%) other than disease progression compared to the other regimens. Abiraterone, enzalutamide, and apalutamide have comparable oncologic outcomes in terms of OS, CSS, and time to CRPC in patients with high-risk mHSPC. Our data on differential treatment discontinuation rates, PSA response, and AE profiles can help guide clinical decision-making.

Yanagisawa T ，Fukuokaya W ，Hatakeyama S ，Narita S ，Muramoto K ，Katsumi K ，Takahashi H ，Urabe F ，Mori K ，Tashiro K ，Iwatani K ，Shimomura T ，Habuchi T ，Kimura T ... -  《-》