Prostate-specific Antigen Progression Research Articles

[177Lu]Lu-PSMA-617 plus enzalutamide in patients with metastatic castration-resistant prostate cancer (ENZA-p): an open-label, multicentre, randomised, phase 2 trial

Enzalutamide and lutetium-177 [177Lu]Lu-prostate-specific membrane antigen (PSMA)-617 both improve overall survival in patients with metastatic castration-resistant prostate cancer. Androgen and PSMA receptors have a close intracellular relationship, with data suggesting complementary benefit if targeted concurrently. In this study, we assessed the activity and safety of enzalutamide plus adaptive-dosed [177Lu]Lu-PSMA-617 versus enzalutamide alone as first-line treatment for metastatic castration-resistant prostate cancer. ENZA-p was an open-label, randomised, controlled phase 2 trial done at 15 hospitals in Australia. Participants were men aged 18 years or older with metastatic castration-resistant prostate cancer not previously treated with docetaxel or androgen receptor pathway inhibitors for metastatic castration-resistant prostate cancer, gallium-68 [68Ga]Ga-PSMA-PET-CT (PSMA-PET-CT) positive disease, Eastern Cooperative Oncology Group performance status of 0-2, and at least two risk factors for early progression on enzalutamide. Participants were randomly assigned (1:1) by a centralised, web-based system using minimisation with a random component to stratify for study site, disease burden, use of early docetaxel, and previous treatment with abiraterone acetate. Patients were either given oral enzalutamide 160 mg daily alone or with adaptive-dosed (two or four doses) intravenous 7·5 GBq [177Lu]Lu-PSMA-617 every 6-8 weeks dependent on an interim PSMA-PET-CT (week 12). The primary endpoint was prostate-specific antigen (PSA) progression-free survival, defined as the interval from the date of randomisation to the date of first evidence of PSA progression, commencement of non-protocol anticancer therapy, or death. The analysis was done in the intention-to-treat population, using stratified Cox proportional hazards regression. This trial is registered with ClinicalTrials.gov, NCT04419402, and participant follow-up is ongoing. 162 participants were randomly assigned between Aug 17, 2020, and July 26, 2022. 83 men were assigned to the enzalutamide plus [177Lu]Lu-PSMA-617 group, and 79 were assigned to the enzalutamide group. Median follow-up in this interim analysis was 20 months (IQR 18-21), with 32 (39%) of 83 patients in the enzalutamide plus [177Lu]Lu-PSMA-617 group and 16 (20%) of 79 patients in the enzalutamide group remaining on treatment at the data cutoff date. Median age was 71 years (IQR 64-76). Median PSA progression-free survival was 13·0 months (95% CI 11·0-17·0) in the enzalutamide plus [177Lu]Lu-PSMA-617 group and 7·8 months (95% CI 4·3-11·0) in the enzalutamide group (hazard ratio 0·43, 95% CI 0·29-0·63, p<0·0001). The most common adverse events (all grades) were fatigue (61 [75%] of 81 patients), nausea (38 [47%]), and dry mouth (32 [40%]) in the enzalutamide plus [177Lu]Lu-PSMA-617 group and fatigue (55 [70%] of 79), nausea (21 [27%]), and constipation (18 [23%]) in the enzalutamide group. Grade 3-5 adverse events occurred in 32 (40%) of 81 patients in the enzalutamide plus [177Lu]Lu-PSMA-617 group and 32 (41%) of 79 patients in the enzalutamide group. Grade 3 events that occurred only in the enzalutamide plus [177Lu]Lu-PSMA-617 group included anaemia (three [4%] of 81 participants) and decreased platelet count (one [1%] participant). No grade 4 or 5 events were attributed to treatment on central review in either group. The addition of [177Lu]Lu-PSMA-617 to enzalutamide improved PSA progression-free survival providing evidence of enhanced anticancer activity in patients with metastatic castration-resistant prostate cancer with risk factors for early progression on enzalutamide and warrants further evaluation of the combination more broadly in metastatic prostate cancer. Prostate Cancer Research Alliance (Movember and Australian Federal Government), St Vincent's Clinic Foundation, GenesisCare, Roy Morgan Research, and Endocyte (a Novartis company).

Radiographic Progression Without Corresponding Prostate-specific Antigen Progression in Patients with Metastatic Castration-sensitive Prostate Cancer Receiving Apalutamide: Secondary Analysis of the TITAN Trial

Background and objectiveIn prostate cancer treated with androgen deprivation therapy (ADT), the initial sign of treatment resistance is often prostate-specific antigen (PSA) progression, followed by radiographic progression. However, the association between these two forms of progression remains unclear, especially in patients with metastatic castration-sensitive prostate cancer (mCSPC) treated with androgen receptor pathway inhibitors. We sought to evaluate the association between radiographic progression, PSA progression, and outcomes of apalutamide therapy in mCSPC. MethodsWe analyzed individual participant-level data for patients randomized within the TITAN trial who experienced radiographic progression during follow-up (N = 326). This study investigated radiographic progression without simultaneous or preceding PSA progression, as defined by the Prostate Cancer Working Group 2 (discordant progression), and explored the association of such progression with radiographic progression-free survival. Key findings and limitationsAmong the patients who developed radiographic progression, 115 (35.3%) had been treated with apalutamide plus ADT (the apalutamide group) and 211 (64.7%) with placebo plus ADT (the placebo group). Discordant progression occurred in 52.2% of patients (60 of 115) in the apalutamide group and 27.5% (58 of 211) in the placebo group (p < 0.001). A multivariable logistic regression analysis showed that discordant progression was associated with apalutamide treatment. We found evidence of an association between discordant progression and shorter radiographic progression-free survival. Conclusions and clinical implicationsThis study found that nearly half of the patients with mCSPC treated with apalutamide who experienced radiographic progression developed it without corresponding PSA progression, suggesting that heavy reliance on PSA monitoring may be inadequate for assessing disease activity in this context. Patient summaryIn patients who have metastatic castration-sensitive prostate cancer (mCSPC) and are being treated with apalutamide, radiographic images may show cancer progression even if prostate-specific antigen tests indicate no change. This highlights the importance of regular imaging when using apalutamide to manage mCSPC.

Enzalutamide Maintenance Following Docetaxel in Metastatic Castration-Naive Prostate Cancer: A Pilot Feasibility Study

Purpose: To assess the feasibility and short-term efficacy of maintenance enzalutamide following first-line docetaxel plus androgen deprivation therapy (ADT) in patients with high-volume, metastatic castration-naive prostate cancer (mCNPC).Materials and Methods: The present study included 38 consecutive patients with mCNPC who did not have disease progression with ADT plus docetaxel between October 2022 and October 2023. Patients received a switch maintenance therapy with enzalutamide until progression, unacceptable toxicity, or patient withdrawal. Endpoints included time to prostate-specific antigen (PSA) progression and safety.Results: Among the 38 patients, the median age was 68 years, and the most frequently observed metastatic site was bone (n=36), followed by lymph nodes (n=28), lung (n=8), and liver (n=1). The median duration of firstline docetaxel was 2.8 months (range, 2.7–5.0 months). At the time of commencing maintenance enzalutamide, the median PSA was 3.2 ng/mL (range, 0.01–258 ng/mL). Maintenance enzalutamide was generally welltolerated. A total of 11 patients (28%) discontinued enzalutamide, and the main reasons included adverse events (prolonged fatigue of grade 1 or 2, n=6), disease progression (n=3) and financial burdens (n=2). Median time to PSA progression was not reached, and 93% were PSA progression-free at 12 months.Conclusions: Maintenance enzalutamide is a feasible treatment option with potential clinical benefit for patients with high-volume mCNPC who were progression-free after first-line ADT+docetaxel.

A Signal-finding Study of Abemaciclib in Heavily Pretreated Patients with Metastatic Castration-Resistant Prostate Cancer: Results from CYCLONE 1.

Cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitors radically changed the treatment paradigm for breast cancer. Similar to estrogen receptor in breast cancer, androgen receptor signaling activates cyclin D-CDK4/6, driving proliferation and resistance to hormonal manipulation in prostate cancer. This study was designed to detect signals of clinical activity for abemaciclib in treatment-refractory metastatic castration-resistant prostate cancer (mCRPC). Eligible patients had progressive mCRPC, measurable disease, and previously received ≥1 novel hormonal agent(s) and 2 lines of taxane chemotherapy. Abemaciclib 200 mg BID was administered on a continuous dosing schedule. Primary endpoint was objective response rate (ORR) without concurrent bone progression. This study was designed to detect a minimum ORR of 12.5%. At trial entry, forty (90.9%) of 44 patients had objective radiographic disease progression, four (9.1%) had prostate-specific antigen (PSA)-only progression, and 20 (46.5%) had visceral metastases (of these, 60% had liver metastases). Efficacy analyses are as follows: ORR without concurrent bone progression: 6.8%; disease control rate: 45.5%; median time to PSA progression: 6.5 months (95% CI: 3.2, NA); median radiographic PFS; 2.7 months (95% CI: 1.9, 3.7); and median OS: 8.4 months (95% CI: 5.6, 12.7). Most frequent grade ≥3 TEAEs were neutropenia (25.0%), anemia, and fatigue (11.4% each). No grade 4 or 5 AEs were related to abemaciclib. Abemaciclib monotherapy was well tolerated and showed clinical activity in this heavily pretreated population, nearly half with visceral metastases. This study is considered preliminary proof-of-concept and designates CDK4/6 as a valid therapeutic target in prostate cancer.

Comparison of Short-Term Outcomes and Safety Profiles between Androgen Deprivation Therapy+Abiraterone/Prednisone and Androgen Deprivation Therapy+Docetaxel in Patients with De Novo Metastatic Hormone-Sensitive Prostate Cancer.

This study aimed to compare the short-term outcomes and safety profiles of androgen-deprivation therapy (ADT)+abiraterone/prednisone with those of ADT+docetaxel in patients with de novo metastatic hormone-sensitive prostate cancer (mHSPC). A web-based database system was established to collect prospective cohort data for patients with mHSPC in Korea. From May 2019 to November 2022, 928 patients with mHSPC from 15 institutions were enrolled. Among these patients, data from 122 patients who received ADT+abiraterone/prednisone or ADT+docetaxel as the primary systemic treatment for mHSPC were collected. The patients were divided into two groups: ADT+abiraterone/prednisone group (n=102) and ADT+docetaxel group (n=20). We compared the demographic characteristics, medical histories, baseline cancer status, initial laboratory tests, metastatic burden, oncological outcomes for mHSPC, progression after mHSPC treatment, adverse effects, follow-up, and survival data between the two groups. No significant differences in the demographic characteristics, medical histories, metastatic burden, and baseline cancer status were observed between the two groups. The ADT+abiraterone/prednisone group had a lower prostate-specific antigen (PSA) progression rate (7.8% vs. 30.0%; p=0.011) and lower systemic treatment discontinuation rate (22.5% vs. 45.0%; p=0.037). No significant differences in adverse effects, oncological outcomes, and total follow-up period were observed between the two groups. ADT+abiraterone/prednisone had lower PSA progression and systemic treatment discontinuation rates than ADT+docetaxel. In conclusion, further studies involving larger, double-blinded randomized trials with extended follow-up periods are necessary.

Relugolix vs. Leuprolide Effects on Castration Resistance-Free Survival from the Phase 3 HERO Study in Men with Advanced Prostate Cancer.

Background: Relugolix is an oral GnRH receptor antagonist approved for men with advanced prostate cancer. Relugolix treatment has demonstrated an ability to lower testosterone to sustained castration levels in the phase 4 HERO study. Herein, we describe the results of a secondary endpoint of castration resistance-free survival (CRFS) during 48 weeks of treatment and profile patients with castration-resistant prostate cancer (CRPC). Methods: Subjects were 2:1 randomized to either relugolix 120 mg orally once daily (after a single 360 mg loading dose) or 3-monthly injections of leuprolide for 48 weeks. CRFS, defined as the time from the date of first dose to the date of confirmed prostate-specific antigen progression while castrated or death due to any reason was conducted in the metastatic disease population and the overall modified intention-to-treat (mITT) populations. Results: The CRFS analysis (mITT population) included 1074 men (relugolix: n = 717; leuprolide: n = 357) with advanced prostate cancer as well as 434 men (relugolix: n = 290; leuprolide: n = 144) with metastatic prostate cancer. In the metastatic disease populations, CRFS rates were 74.3% (95% CI: 68.6%, 79.2%) and 75.3% (95% CI: 66.7%, 81.9%) in the relugolix and leuprolide groups, respectively (hazard ratio: 1.03 [0.68, 1.57]; p = 0.84) at week 48. Results in the overall mITT population were similar to the metastatic population. No new safety findings were identified. Conclusions: In men with metastatic disease or in the overall population of the HERO study, CRFS assessed during the 48-week treatment with relugolix was not significantly different than standard-of-care leuprolide. Relugolix had similar efficacy for men with/without CRFS progression events.

Prospective Assessment of Bone Metabolism Biomarkers and Survival in Metastatic Castration-resistant Prostate Cancer Patients Treated with Radium-223: The PRORADIUM Study

BackgroundRadium-223 is an active therapy option for bone metastatic castration-resistant prostate cancer (mCRPC). The lack of adequate biomarkers for patient selection and response assessment are major drawbacks for its use. ObjectiveTo assess the prognostic value of bone metabolism biomarkers (BMBs) in ra-223–treated mCRPC patients. Design, setting, and participantsA prospective cohort study of mCRPC patients treated with Ra-223 (PRORADIUM study: NCT02925702) was conducted. Outcome measurements and statistical analysisThe main objective of the study was to evaluate the association between high (≥median) baseline values in at least three bone formation (bone alkaline phosphatase [BAP] and C-terminal type-I collagen propeptide) and bone resorption (N-terminal telopeptide and pyridinoline) biomarkers, and survival. The independent prognostic value of each BMB was also assessed. The association with time to radiographic, clinical, and prostate-specific antigen (PSA) progression; time to skeletal-related events; and PSA response were secondary objectives. Multivariable (MV) Cox-regression models were evaluated. Results and limitationsA total of 169 patients were included. Of the patients, 70.4% received Ra-223 in second/third line; 144 (85.2%) were Eastern Cooperative Oncology Group 0–1, 126 (74.6%) were in pain, and 80 (47.5%) had more than ten bone metastases. Sixty-seven (39.6%) patients had elevation in at least three BMBs. The median overall survival was 12.1 mo (95% confidence interval [CI]: 10–14.7). No association was observed with other treatment-related secondary outcome parameters. Patients with high values in three or more BMBs had significantly worse survival (9.9 vs 15.2 mo; hazard ratio [HR]: 1.8 [95% CI: 1.3–2.5]; p < 0.001) in the univariate analysis, but not independent in the MV analysis (HR: 1.33; 95% CI: 0.89–2; p = 0.181). High baseline BAP was the only biomarker associated with survival in the MV model (HR: 1.89; 95% CI: 1.28–2.79; p = 0.001). Addition of BAP to the MV clinical model increased the area under the receiver operating characteristic curve 2-yr value from 0.667 to 0.755 (p = 0.003). ConclusionsBiomarkers of bone formation, especially BAP, have prognostic value in mCRPC patients treated with radium-223. Its predictive value remains to be assessed, ideally in prospective, adequately powered, randomised clinical trials. Patient summaryIn this study, we evaluate the role of bone metabolism biomarkers to help improve the use of radium-223 as therapy for advanced prostate cancer. We found that bone alkaline phosphatase may be a suitable tool.

The efficacy of STRATAFIX® spiral PDS for vesicourethral anastomosis during robot-assisted laparoscopic radical prostatectomy: a single-center retrospective study.

To investigate the efficacy of continuous suturing using barbed suture for vesicourethral anastomosis (VUA) during robot-assisted laparoscopic radical prostatectomy (RARP). Seventy-three consecutive patients who underwent RARP by a single surgeon between 2020 and 2022 were retrospectively divided based on the suture type used for VUA: group A, 3-0 poliglecaprone-25 RB-1 needle (Monocryl®), n = 46; group B, 3-0 spiral polydioxanone (PDS) barbed suture with RB-1 needle (STRATAFIX®), n = 27. There was no significant difference in patient background characteristics between groups, including age, body mass index, and clinical stage. However, group B had a significantly shorter operative time, console time, hospital stay, and duration of urethral catheterization. The VUA time was significantly shorter in group B than in group A (17.9min vs. 10.6min; p < 0.001). Only 1 case of minor leakage was observed during the intraoperative leak test (1 patient in group A). There was no significant difference in the number of pads used at 1, 3,6months and 1year postoperatively. There were no urethral strictures, and there was no significant difference in pathologic results or postoperative prostate-specific antigen progression between groups. Our study suggests that the use of barbed suture during VUA for RARP is associated with reduced VUA time.

Prognostic Value of End-of-Treatment PSMA PET/CT in Patients Treated with 177Lu-PSMA Radioligand Therapy: A Retrospective, Single-Center Analysis.

Our objective was to evaluate the prognostic value of end-of-treatment prostate-specific membrane antigen (PSMA) PET/CT (PSMA-PET) in patients with metastatic castration-resistant prostate cancer (mCRPC) treated with 177Lu-PSMA radioligand therapy (PSMA-RLT). Methods: This was a single-center retrospective study. mCRPC patients who underwent PSMA-RLT with available baseline PSMA-PET (bPET) and end-of-treatment PSMA-PET (ePET) within 6 mo of the last PSMA-RLT cycle were eligible. Overall survival (OS) and prostate-specific antigen (PSA) progression status at the time of ePET (by Prostate Cancer Clinical Trials Working Group 3 criteria) were collected. PSMA-PET tumor segmentation was performed to obtain whole-body PSMA tumor volume (PSMA-VOL) and define progressive (≥20% increase) versus nonprogressive disease. Pairs of bPET and ePET were interpreted for appearance of new lesions. Response Evaluation Criteria in PSMA-PET/CT (RECIP) 1.0 were also applied to define progressive versus nonprogressive disease. The associations between changes in PSMA-VOL, new lesions, RECIP 1.0, and PSA progression status at the time of ePET with OS were evaluated by Kaplan-Meier analysis. Results: Twenty mCRPC patients were included. The median number of treatment cycles was 3.5 (interquartile range [IQR], 2-4). The median time between bPET and cycle 1 of PSMA-RLT was 1.0 mo (IQR, 0.7-1.8 mo). The median time between the last cycle of PSMA-RLT and ePET was 1.9 mo (IQR, 1.2-3.5 mo). Twelve of 20 patients (60%) had died at the last follow-up. The median follow-up time from ePET for survivors was 31.2 mo (IQR, 6.8-40.7 mo). The median OS from ePET was 11.4 mo (IQR, 6.8-30.7 mo). Patients with new lesions on ePET had shorter OS than those without new lesions (median OS, 10.7 mo [95% CI, 9.2-12.2] vs. not reached; P = 0.002). Patients with progressive PSMA-VOL had shorter OS than those with nonprogressive PSMA-VOL (median OS, 10.7 mo [95% CI: 9.7-11.7 mo] vs. not reached; P = 0.007). Patients with progressive RECIP had shorter OS than those with nonprogressive RECIP (median OS, 10.7 mo [95% CI, 9.7-11.7 mo] vs. not reached; P = 0.007). PSA progression at the time of ePET was associated with shorter OS (median, 10.9 mo [95% CI, 9.4-12.4 mo] vs. not reached; P = 0.028). Conclusion: In this retrospective study of 20 mCRPC patients treated with PSMA-RLT, progression on ePET by the appearance of new lesions, changes in PSMA-VOL, and RECIP 1.0 was prognostic for OS. Validation in larger, prospective multicentric clinical trials is warranted.

Correlation between E-cadherin/β-catenin, Vimentin expression, clinicopathologic features and drug resistance prediction in naïve prostate cancer: A molecular and clinical study.

Although epithelial-mesenchymal markers play an important role in prostate cancer (PC), further research is needed to better understand their utility in diagnosis, cancer progression prevention, and treatment resistance prediction. Our study included 111 PC patients who underwent transurethral resection, as well as 16 healthy controls. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to examine the expression of E-cadherin, β-catenin, and Vimentin. We found that E-cadherin and β-catenin were underexpressed in primary PC tissues. E-cadherin expression was found to be inversely associated with prostate-specific antigen progression (PSA-P; serum marker of progression; p = 0.01; |r| = 0.262). Furthermore, the underexpression of two markers, E-cadherin and β-catenin, was found to be associated with advanced tumor stage and grade (p < 0.05). On the other hand, Vimentin was overexpressed in PC patients with a fold change of 2.141, and it was associated with the diagnosis, prognosis, and prediction of treatment resistance to androgen deprivation therapy (p = 0.002), abiraterone-acid (p = 0.001), and taxanes (p = 0.029). Moreover, the current study highlighted that poor survival could be significantly found in patients who progressed after primary surgery, did not use drugs, and expressed these genes aberrantly. In Cox regression multivariate analysis (p < 0.05), a positive correlation between the Vimentin marker and coronary heart disease in PC patients was identified (p = 0.034). In summary, the present study highlights the diagnostic (p < 0.001), prognostic (p < 0.001), and therapeutic potential of Vimentin in primary PC (p < 0.05), as well as its implications for cardiovascular disease. Furthermore, we confirm the potential prognostic value of E-cadherin and β-catenin.

Apalutamide plus androgen deprivation therapy in clinical subgroups of patients with metastatic castration-sensitive prostate cancer: A subgroup analysis of the randomised clinical TITAN study

BackgroundWhether disease burden in patients with metastatic castration-sensitive prostate cancer (mCSPC) predicts treatment outcomes is unknown. We assessed apalutamide treatment effect in TITAN patients with mCSPC by disease volume, metastasis number and timing of metastasis presentation. MethodsThese protocol-defined and post hoc analyses of the phase III randomised TITAN study evaluated clinical outcomes in patients receiving 240 mg/day apalutamide (n = 525) or placebo (n = 527) plus androgen-deprivation therapy (ADT). Subgroups were defined by volume (high: visceral and ≥1 bone metastases or ≥4 bone lesions with ≥1 beyond vertebral column/pelvis), development of metastases per conventional imaging (synchronous: at initial diagnosis; metachronous: after localised disease) and oligometastases (≤5 bone-only metastases) or polymetastases (>5 in bone ± other locations or ≤5 in bone plus other locations). Overall survival (OS), radiographic or second progression-free survival, and time to prostate-specific antigen progression or castration resistance were assessed using Cox proportional hazards models. ResultsOf 1052 patients, 63%, 81%, 54%, 27%, 5.7%, and 8.0% had high-volume, synchronous, synchronous/high-volume, synchronous/low-volume, metachronous/high-volume, and metachronous/low-volume disease, respectively. The OS benefit favoured apalutamide plus ADT versus ADT alone in synchronous/high-volume (hazard ratio = 0.68 [95% confidence interval: 0.53–0.87]; p = 0.002), synchronous/low-volume (0.65 [0.40–1.05]; p = 0.08), metachronous/high-volume (0.69 [0.33–1.44]; p = 0.32) and metachronous/low-volume (0.22 [0.09–0.55]; p = 0.001) subgroups. Apalutamide improved other clinical outcomes regardless of subgroup, with similar safety profiles. Most favourable outcomes were observed in oligometastatic disease. ConclusionTITAN patients derived a robust benefit with apalutamide plus ADT regardless of disease volume and timing of metastasis presentation without differences in safety, supporting early apalutamide intensification in mCSPC. Clinical Trial RegistrationNCT02489318.

Circulating Tumor DNA Analysis on Metastatic Prostate Cancer with Disease Progression.

The positivity rate of circulating tumor DNA (ctDNA) next-generation sequencing (NGS) varies among patients with metastatic prostate cancer (mPC), complicating its incorporation into regular practice. This retrospective study analyzed the ctDNA sequencing results of 100 mPC patients from May 2021 to March 2023 to identify the factors associated with positive ctDNA. Three custom gene panels were used for sequencing. Overall, 63% of the patients exhibited tier I/II somatic alterations, while 12% had pathogenic/likely pathogenic germline alterations. The key genes that were altered included AR, TP53, RB1, PTEN, and APC. Mutations in BRCA1/2, either germline or somatic, were observed in 21% of the patients. Among the metastatic castration-resistant prostate cancer (mCRPC) patients, the ctDNA-positive samples generally showed higher median prostate-specific antigen (PSA) levels and were more likely to be at the radiographic and clinical progressive disease stages, although they were not significantly associated with PSA progression. Our results suggest that ctDNA analysis could detect meaningful genetic changes in mPC patients, especially during disease progression.

Risk-stratified multi-round PSA screening for prostate cancer integrating the screening reference level and subgroup-specific progression indicators

BackgroundAlthough prostate-specific antigen (PSA) is widely used in prostate cancer (PCa) screening, nearly half of PCa cases are missed and less than one-third of cases are non-lethal. Adopting diagnostic criteria in population-based screening and ignoring PSA progression are presumed leading causes.MethodsA total of 31,942 participants with multi-round PSA tests from the PLCO trial were included. Time-dependent receiver-operating-characteristic curves and area under curves (tdAUCs) were performed to determine the screening reference level and the optimal subgroup-specific progression indicator. Effects of risk-stratified multi-round PSA screening were evaluated with multivariable Cox regression and measured with hazard ratio [HR (95%CIs)].ResultsAfter a median follow-up of 11.6 years, a total of 3484 PCa cases and 216 PCa deaths were documented. The tdAUC of 10-year incidence PCa with PSA was 0.816, and the cut-off value was 1.61 ng/ml. Compared to subgroup with stable negative PSA in both first-round (FR) and last-round (LR) tests [FR(−)/LR(−)], HRs (95%CI) of PCa incidence were 1.66 (1.20–2.29), 8.29 (7.25–9.48), and 14.52 (12.95–16.28) for subgroups with loss of positive PSA[FR(+)/LR(−)], gain of positive PSA[FR(−)/LR(+)], and stable positive PSA[FR(+)/LR(+)]; while HRs(95%CI) of PCa mortality were 1.47 (0.52–4.15), 5.71 (3.68–8.86), and 5.01 (3.41–7.37). After excluding regressive PSA [(namely FR(+)/LR(−)], absolute velocity was the shared optimal progression indicator for subgroups with FR(−)/LR(−), FR(−)/LR(+), and FR(+)/LR(+), with tdAUCs of 0.665, 0.681 and 0.741, and cut-off values of 0.07, 0.21, and 0.33 ng/ml/year. After reclassifying participants into groups with positive and negative progression based on subgroup-specific progression indicators, incidence HR (95%CI) were 2.41 (1.87–3.10), 2.91 (2.43–3.48), and 3.16 (2.88–3.46) for positive progression compared to negative progression within subgroups of FR(−)/LR(−), FR(−)/LR(+), and FR(+)/LR(+), while mortality HR (95%CI) were 2.22 (0.91–5.38), 2.37 (1.28–4.38), and 2.98 (1.94–4.59). To improve screening performances by excluding regressive PSA and low-risk positive progression in FR(−)/LR(−), optimized screening strategy not only significantly reduce 32.4% of missed PCa (54.0% [1881/3484] vs. 21.6% [754/3484], P < 0.001), but also detected additional 8.0% of high-grade PCa (Gleason score 7–10: 36.0% [665/1849] vs. 28.0% [206/736], P < 0.001) than traditional screening strategy.ConclusionsRisk-stratified multi-round PSA screening strategy integrating the screening reference level and the optimal subgroup-specific progression indicator of PSA could be recommended as a fundamental strategy to reduce missed diagnosis and improve the detection of high-grade PCa cases.

Real-world analysis of metastatic prostate cancer demonstrates increased frequency of PSA-imaging discordance with visceral metastases and upfront ARAT/docetaxel therapy.

The objective of this study was to evaluate the background and treatment course of patients with metastatic prostate cancer (PC), with a particular focus on radiographic progression in the absence of prostate-specific antigen (PSA) progression. The study population consisted of 229 patients with metastatic hormone-sensitive PC (HSPC), who received prostate biopsy and androgen deprivation therapy at Kobe University Hospital between January 2008 and June 2022. Clinical characteristics were retrospectively evaluated using medical records. PSA progression-free status was defined as ≤1.05 times greater than that from 3 months before. Multivariate analyses were performed using the Cox proportional hazards regression model to identify parameters associated with time to progression on imaging without PSA elevation. A total of 227 patients with metastatic HSPC without neuroendocrine PC were identified. The median follow-up period was 38.0 months, with a median overall survival of 94.9 months. Six patients exhibited disease progression on imaging without PSA elevation during HSPC treatment, three during first-line castration-resistant PC (CRPC) treatment, and two during late-line CRPC treatment. The rate of disease progression without PSA elevation at 3 years after treatment initiation was 7.4%. Multivariate analysis revealed that organ metastases and upfront treatment with docetaxel or androgen receptor axis-targeted therapy were independent prognostic factors for imaging progression without PSA elevation. Disease progression on imaging without PSA elevation occurred not only during HSPC treatment and first-line CRPC treatment, but also during late-line CRPC treatment. Patients with visceral metastases or those treated with upfront androgen receptor axis-targeted or docetaxel may be more prone to such progression.

Associations between sarcopenia and clinical outcomes in men with metastatic castrate-resistant prostate cancer.

12056 Background: Understanding the impact of sarcopenia on clinical outcomes in patients with metastatic cancer will assist clinicians with risk stratification, treatment decision-making, and inform the need for targeted supportive care strategies. Our objective was to comprehensively assess sarcopenia using measures of muscle mass (radiographically) and function (i.e., muscle strength and walking speed) and examine its impact on severe treatment toxicity, time to first emergency room (ER) visit, prostate-specific antigen (PSA) progression, radiographic progression, and overall mortality in men initiating androgen receptor-axis targeted therapy (ARAT) or chemotherapy for mCRPC. Methods: This was a secondary analysis of a prospective observational study of older men with mCRPC at the Princess Margaret Cancer Centre. Sarcopenia was defined as the combination of low muscle strength (grip strength &lt; 35.5kg), slowness (walking speed &lt; 0.8m/s), and low muscle quantity or quality prior to treatment initiation. The skeletal muscle index and skeletal muscle density were assessed through computed tomography scans prior to ARAT or chemotherapy initiation to determine muscle quantity and quality, respectively, using published cut-offs. Severe treatment toxicity, unplanned healthcare use, and disease progression were assessed from treatment initiation until treatment termination or loss to follow up. The associations between sarcopenia and severe treatment toxicity (i.e., grade 3+ toxicity) were assessed using multivariable logistic regression. Survival analyses were used to assess the impact of sarcopenia on the time to first ER visit, PSA progression, radiographic progression, and overall mortality. An interaction term for sarcopenia by treatment was introduced in all multivariable models and when necessary, an analysis by treatment was performed. Results: In total, 110 men participated, of whom 30 (27.3%) had sarcopenia prior to initiating treatment. Sarcopenia was associated with severe treatment toxicity (adjusted odds ratio (aOR) = 6.26, 95%CI = 1.17-33.58, P = 0.032) and time to first ER visit (adjusted hazard ratio (aHR) = 4.41, 95%CI = 1.26-15.43, p = 0.020) in the group that was initiating ARAT but not chemotherapy. Sarcopenia was a significant predictor of radiographic progression (aHR = 2.39, 95%CI = 1.06-5.36, p = 0.035) and overall mortality (aHR = 2.44, 95%CI = 1.17-5.08, p = 0.018) in the entire cohort. Conclusions: Sarcopenia may predict severe treatment toxicity and emergency room visits in men starting ARAT for mCRPC. Additionally, sarcopenia predicts radiographic progression and overall mortality regardless of treatment type in men with mCRPC. Confirmation is needed from large-scale studies. Assessment of sarcopenia can assist clinicians in treatment decision making while identifying high-risk patients that require targeted supportive care strategies.

PSMAddition: A phase 3 trial to compare treatment with 177Lu-PSMA-617 plus standard of care (SoC) and SoC alone in patients with metastatic hormone-sensitive prostate cancer.

TPS5116 Background: Lutetium (177Lu) vipivotide tetraxetan (177Lu-PSMA-617) plus protocol-permitted standard of care (SoC) significantly improved radiographic progression-free survival (rPFS) and overall survival (OS) in patients with prostate-specific membrane antigen (PSMA)-positive metastatic castration-resistant prostate cancer, previously treated with at least one androgen receptor pathway inhibitor (ARPI) and one or two taxanes. Androgen deprivation therapy (ADT) and ARPIs may alter PSMA expression and radiosensitivity. PSMAddition will assess the efficacy and safety of 177Lu-PSMA-617 plus SoC versus SoC alone in adults with metastatic hormone-sensitive prostate cancer (mHSPC). Methods: PSMAddition (NCT04720157) is an international, prospective, open-label, randomized, phase 3 trial, with crossover, in adults with mHSPC. Eligible patients are treatment-naive or minimally treated candidates for hormonal therapy, with PSMA-positive disease (determined by 68Ga-PSMA-11 PET/CT), ECOG performance status of 0 to 2 and adequate major organ function. Patients are excluded if they have rapidly progressing tumors that require chemotherapy. Approximately 1126 patients will be randomized 1:1 to receive 177Lu-PSMA-617 (7.4 GBq every 6 weeks for a maximum of 6 cycles) plus SoC or SoC alone (an ARPI and ADT). Stratification factors are tumor volume (high/low), age (≥ 70/ &lt; 70 years), and previous/planned prostatectomy or radiation treatment of the primary prostate tumor (yes/no). Recruitment for a China extension cohort (40–60 patients) will follow after completion of main study recruitment. The primary endpoint is rPFS, as assessed by blinded independent centralized review. Upon centrally confirmed radiographic progression, participants in the SoC-only arm can cross over to the 177Lu-PSMA-617 arm. The planned sample size provides 95% power to detect a hazard ratio of 0.7 for rPFS after 418 events with an overall one-sided significance level of 0.025. The key secondary endpoint is OS, others include the proportion of patients with a prostate-specific antigen (PSA) decline of ≥ 90% from baseline, time to development of metastatic castration-resistant prostate cancer, composite PFS (radiographic, clinical or PSA progression), safety and tolerability, and health-related quality of life. Imaging and biospecimen (tissue and blood) collection is embedded for correlative analysis. Participants who have received 177Lu-PSMA-617 will have the option to enroll in a separate long-term safety follow-up study. Updated from previous presentation at the 2021 European Society for Medical Oncology Congress, FPN 3035, with permission. Clinical trial information: NCT04720157 .

Darolutamide observational (DAROL) study in patients with nonmetastatic castration-resistant prostate cancer: Second interim analysis.

e17095 Background: In ARAMIS (NCT02200614), darolutamide (DARO) significantly improved metastasis-free survival (MFS) by ~2 years (HR 0.41, 95% CI 0.34–0.50) and reduced the risk of death by 31% (HR 0.69, 95% CI 0.53–0.88) compared with placebo in men with nonmetastatic castration-resistant prostate cancer (nmCRPC), with a favorable tolerability profile. The ongoing DAROL study (NCT04122976) aims to understand the real-world safety and effectiveness of DARO in patients (pts) with nmCRPC. We report results from the pre-planned second interim analysis (IA). Methods: DAROL is a global, open-label, single-arm, non-interventional study in pts aged ≥18 years with confirmed nmCRPC for whom the decision to be treated with DARO is decided pre-enrollment. The primary endpoint is safety, including incidence, severity, and frequency of treatment-emergent adverse events (TEAEs). Secondary endpoints are patient demographics and disease characteristics, treatment duration, MFS, overall survival (OS), time to prostate-specific antigen (PSA) progression, and PSA response. Primary and secondary endpoints are reported after 300 pts completed ≥6 mo of treatment. All treated pts were assessed for safety while efficacy was evaluated in pts who did not violate any eligibility criteria and had ≥1 post-baseline assessment (cut-off October 11, 2022). Results: Of the 300 treated pts, the percentage enrolled in North America/Europe/Asia Pacific/Latin America was 45%/30%/25%/ &lt; 1%, respectively. Median age was 80 years; 51% had a reported Gleason score &gt; 7; 92% had a reported ECOG performance status of 0/1. Median baseline (BL) PSA was 3.9 ng/mL (range 0–248.0), with 21% of pts reporting PSA &lt; 2 ng/mL. Median BL PSA doubling time (PSADT) was 5.3 mo (range 0–36.2), with 42% of pts reporting PSADT &gt; 6 mo. At the data cut-off, median follow-up time was 14.8 mo (interquartile range [IQR] 10.9–19.3) and median treatment duration was 13.4 mo (IQR 9.3–17.8). The incidences of TEAEs and DARO-related TEAEs were generally low (Table), consistent with the safety profile of DARO reported in ARAMIS. Fatigue occurred in ≥5% of pts. For the 263 pts eligible for efficacy analysis, median time to PSA progression was 17.6 mo (95% CI 13.2–19.0); MFS/OS data remain immature. PSA declines from baseline of ≥30%, ≥50%, and ≥90% at any time were observed in 80%, 76%, and 54% of pts, respectively. Conclusions: In the DAROL second IA, under real-world conditions, DARO continued to show a favorable safety profile, consistent with the clinical profile of ARAMIS, with no new safety signals. Clinical trial information: NCT04122976 . [Table: see text]

Efficacy and safety of darolutamide in Chinese patients with metastatic hormone-sensitive prostate cancer (mHSPC): A subpopulation analysis of the phase 3 ARASENS study.

e17076 Background: Darolutamide (DARO) is an androgen receptor inhibitor approved in China for the treatment of nonmetastatic castration-resistant prostate cancer (CRPC). In the global ARASENS trial, DARO significantly increased overall survival (OS) vs placebo (PBO) in patients (pts) with mHSPC. The efficacy and safety of DARO in the Chinese subpopulation of ARASENS are reported here. Methods: In this randomized, double-blind phase 3 trial, 1305 pts with mHSPC were randomized 1:1 to receive DARO 600 mg orally twice daily or PBO, in combination with androgen-deprivation therapy (ADT) and docetaxel. The primary endpoint was OS. Results: In mainland China, 202 pts were randomized to the DARO group (n = 104) or the PBO group (n = 98). Demographics and baseline characteristics were well balanced between treatment groups and comparable to the overall ARASENS population, except for a slightly higher proportion of pts with Gleason score ≥8, higher proportion with metastatic disease at diagnosis, and higher median baseline prostate-specific antigen (PSA) in Chinese pts vs the overall population. The risk of death was reduced by 36% (HR 0.64, 95% CI 0.41–0.99) with DARO vs PBO in Chinese pts (Table). The key secondary endpoint time to CRPC (HR 0.32, 95% CI 0.20–0.50) and the exploratory endpoint time to PSA progression (HR 0.22, 95% CI 0.13–0.37) also favored DARO. In the DARO group, 81% of pts had a maximum PSA decline of ≥90% from baseline (PSA90) at week 12, while 88% had PSA90 and 71% reached PSA &lt; 0.2 ng/mL at any time. Incidences of treatment-emergent adverse events (TEAEs) in Chinese pts were similar between treatment groups and comparable to the overall population. The most common grade 3/4 TEAE in Chinese pts was neutropenia (DARO 64%, PBO 62%), a known toxicity of docetaxel; grade 3/4 febrile neutropenia occurred in 4.0% of Chinese pts compared with 7.6% in the overall population. Conclusions: In the ARASENS subpopulation of Chinese pts with mHSPC, DARO + ADT + docetaxel showed favorable efficacy and safety vs PBO + ADT + docetaxel: OS and clinically relevant secondary endpoints favored DARO vs PBO, and the incidences of TEAEs were similar in the two treatment groups. These results are consistent with the findings reported for the overall population in ARASENS. Clinical trial information: NCT02799602 . [Table: see text]

A prospective trial of apalutamide and abiraterone acetate plus prednisone in Black and White men with metastatic castrate-resistant prostate cancer.

5015 Background: Abi Race was the first prospective parallel cohort study of abiraterone acetate plus prednisone (AAP) in Black and White men with metastatic castrate-resistant prostate cancer (mCRPC) and demonstrated greater prostate-specific antigen (PSA) response, time to PSA progression (TTP) and toxicity rates among Black patients (pts). We designed the PANTHER trial to estimate clinical outcomes among Black and White pts with mCRPC treated with apalutamide, abiraterone, plus prednisone. Methods: This parallel cohort multicenter study treated androgen receptor pathway inhibitor naïve mCRPC pts with oral apalutamide (240 mg/d), abiraterone (1000 mg/d) and prednisone (10 mg/d) (AAAP) continuously until disease progression, unacceptable toxicity or 2 years. The primary endpoint was radiographic progression free survival (rPFS); secondary endpoints were to estimate TTP, overall survival (OS) and best PSA response, among Black and White pts, separately. Exploratory endpoints included safety and correlative biomarkers of outcome by race and ancestry. Results: Between July 2017 and January 2021, we enrolled 43 Black and 50 White pts from 8 sites. Baseline prognostic characteristics were largely similar with some differences. We report an interim analysis as the pts are still followed for OS. At the time of the abstract submission, there were 18 and 36 rPFS events and 15 and 30 deaths in Black and White pts, respectively. We present the time to event endpoint rates at 12 and 24 mos and PSA declines for Black and White pts. Conclusions: We hypothesize that treatment with the combination of AAAP may result in clinical efficacy in Black men with mCRPC. Black pts were underrepresented in the phase III ACIS trial which compared AAP to AAAP and demonstrated longer rPFS but not OS. Further studies of AAAP combination therapy among Black men with advanced prostate cancer are needed to determine potential clinical benefits in this understudied population. Clinical trial information: NCT03098836 . [Table: see text]

LBA02-09 EMBARK: A Phase 3 Randomized Study of Enzalutamide or Placebo Plus Leuprolide Acetate and Enzalutamide Monotherapy in High-risk Biochemically Recurrent Prostate Cancer

Within 10 years following definitive therapy for prostate cancer, ∼20-50% of patients (pts) experience biochemical recurrence (BCR) characterized by rising prostate-specific antigen (PSA) levels. Pts with high-risk BCR have an increased risk of mortality and improved therapies are needed. The objective of EMBARK was to evaluate the efficacy and safety of enzalutamide (enza) + androgen deprivation therapy (ADT) and enza monotherapy (mono) in pts with high-risk BCR. EMBARK is a randomized, phase 3 study of pts with BCR considered high-risk: PSA doubling time ≤9 months and PSA ≥2 ng/mL above nadir post-radiotherapy (RT) or ≥1 ng/mL after radical prostatectomy (RP) ± postoperative RT. Pts were randomized (1:1:1) to enza 160 mg/day + LA (double-blind), placebo (pbo) + LA (double-blind), or enza mono (open-label). LA 22.5 mg was administered every 12 weeks. If the PSA at week 36 was <0.2 ng/mL, therapy was stopped at week 37 and restarted when PSA was ≥2 ng/mL for pts with primary RP, and ≥5 ng/mL for pts without RP. The primary endpoint, determined by blinded, independent central review (BICR), was metastasis-free survival (MFS) with enza + LA vs pbo + LA. Key secondary endpoints were MFS of enza mono vs pbo + LA, time to PSA progression, time to antineoplastic therapy, and overall survival (OS) of enza + LA or enza mono vs pbo + LA. 1068 pts were randomized into the study (enza + LA, n=355; pbo + LA, n=358; enza mono, n=355). After median follow-up of 60.7 months, per BICR, MFS for enza + LA (HR 0.42; 95% CI 0.30-0.61; p<0.0001) and enza mono (HR 0.63; 95% CI 0.46-0.87; p=0.0049) were statistically superior to pbo + LA. Statistically significant improvements were also observed in risk of PSA progression (enza + LA: HR 0.07; 95% CI, 0.03-0.14; enza mono: HR 0.33; 95% CI, 0.23-0.49; both p<0.0001) and time to first use of new antineoplastic therapy (enza + LA: HR 0.36; 95% CI, 0.26-0.49; enza mono: HR 0.54; 95% CI, 0.41-0.71; both p<0.0001). Interim OS data trended in favor enza + LA (HR 0.59; 95% CI, 0.38-0.90; p=0.0142, did not cross interim efficacy boundary) and enza mono (HR 0.77; 95% CI, 0.51-1.15; p=0.1963). Fatigue and hot flash were the most common adverse events; no new safety signals were observed. In pts with high-risk BCR, enza + ADT and enza mono demonstrated a statistically significant and clinically meaningful improvement in MFS vs pbo + ADT. The safety profile of enza was consistent with results from previous clinical studies. NCT02319837. Pfizer Inc. and Astellas Pharma Inc.Conflict of Interest and Disclosure Statement:Neal D. Shore reports grant support and consulting fees from AbbVie, Amgen, Astellas Pharma Inc., AstraZeneca, Bayer, Clovis Oncology, Dendreon Pharmaceuticals LLC, Ferring Pharmaceuticals, GenesisCare, Janssen Oncology, Merck, Myovant Sciences, Pfizer Inc., Sanofi-Genzyme, and Tolmar Pharmaceuticals, Inc. Murilo de Almeida Luz reports receiving speaker honoraria from Astellas Pharma Inc., Bayer, Janssen, Merck Sharp & Dohme, and Pfizer Inc.; being an advisory board member for Astellas Pharma Inc., Bayer, and Janssen; sponsored research from Bayer, Bristol Myers Squibb, Ferring Pharmaceuticals, GlaxoSmithKline, Janssen, and Roche; receiving travel expenses from AstraZeneca, Bayer, Janssen, and Pfizer Inc. Ugo De Giorgi reports serving as a consultant for Janssen, Astellas Pharma Inc., Sanofi, Bayer, Pfizer Inc., Bristol Myers Squibb, Novartis, Ipsen, and Merck Sharp & Dohme. Martin Gleave reports stock or ownership interest in OncoGenex Technologies Inc., Sustained Therapeutics Inc., and Sikta Biopharma; is a consultant to Astellas Pharma Inc., AstraZeneca, Bayer, Genova Diagnostics (GDx), Janssen, Pfizer Inc., Roche, Sanofi, and TerSera Therapeutics LLC; and holds patents for OGX-011, OGX-427, ST-CP, and ST-POP. Geoffrey T. Gotto reports receiving honoraria from Amgen, Astellas Pharma Inc., Bayer, Ferring Pharmaceuticals, Janssen, and Merck; being a consultant or advisory board member for Amgen, Astellas Pharma Inc., Bayer, Janssen, and Merck; providing expert testimony for Janssen; and receiving support for travel, accommodation, and expenses from Janssen. Gabriel P. Haas reports being an employee of and shareholder in Astellas Pharma Inc. Miguel Ramirez-Backhaus reports serving as a consultant or advisory board member for Astellas Pharma Inc., Bayer, Janssen, and Karl Storz; receiving speaker honoraria from Astellas Pharma Inc., Bayer, Janssen, and GP Pharm. Antti Rannikko reports being a board member for the Ida Montin Foundation, and Orion Research Foundation; being an advisory board member for Bayer, Janssen, and Orion Pharma; being a stockholder and clinical advisor for Aqsens Health; being a clinical investigator for Astellas Pharma Inc., Bayer, Janssen, Orion Pharma, and RhoVac AB; and receiving competitive state research funding from HUS Helsinki University Hospital, Finnish Cancer Organizations, and the Jane and Aatos Erkko Foundation. Jamal Tazari, Yiyun Tang, and Fabian Zohren are employees of and shareholders in Pfizer Inc. Swetha Sridharan reports no conflicts of interest. Jennifer Sugg is an employee of Astellas Pharma Inc., and a shareholder in AstraZeneca. Ronald F. Tutrone, Jr. reports being an advisory board member for Bayer; and receiving speaker honoraria from Astellas Pharma Inc., Exosome Diagnostics, Inc., Myovant Sciences, and Pfizer Inc. Balaji Venugopal reports receiving honoraria from Bristol Myers Squibb, Eisai Co., Ltd, EUSA Pharma, Ipsen, Janssen, and Merck; being a consultant or advisory board member for Janssen, Merck Sharp & Dohme Oncology, and Pfizer Inc./EMD Serono; and receiving support for travel, accommodation, and expenses from EUSA Pharma, and Ipsen. Arnauld Villers reports receiving research grants from Astellas Pharma Inc., Ferring Pharmaceuticals, Ipsen, and Janssen. Henry H. Woo reports being an advisory board member for Astellas Pharma Inc., Bayer, Boston Scientific Corporation, and Mundipharma International Ltd; and reports receiving speaker honoraria from AbbVie, Astellas Pharma Inc., Boston Scientific Corporation, and Janssen. Stephen J. Freedland reports being a consultant for Astellas Pharma Inc., AstraZeneca, Bayer, Dendreon Pharmaceuticals LLC, Janssen, Merck, Myovant Sciences, Pfizer Inc., and Sanofi. The authors thank all the patients, their families, and the investigators and investigational site members involved in this study.Editorial Acknowledgement:Medical writing and editorial support was provided by Julie B. Stimmel, PhD, Sinead Stewart and Rosie Henderson, of Onyx (a Prime Global Agency), funded by Pfizer, Inc. and Astellas Pharma Inc., the co-developers of enzalutamide.Submission Category:prostate cancer.Sub-category:Advanced (including drug therapy).