Explore the vast range of titles available.

In a trial, the median metastasis-free survival among men with nonmetastatic, castration-resistant prostate cancer and a short PSA doubling time was 36.6 months with enzalutamide and 14.7 months with placebo. Falls and heart problems were more common with enzalutamide.

Lutetium-177 [177Lu]Lu-PSMA-617 is a radiolabelled small molecule that delivers β radiation to cells expressing prostate-specific membrane antigen (PSMA), with activity and safety in patients with metastatic castration-resistant prostate cancer. We aimed to compare [177Lu]Lu-PSMA-617 with cabazitaxel in patients with metastatic castration-resistant prostate cancer. We did this multicentre, unblinded, randomised phase 2 trial at 11 centres in Australia. We recruited men with metastatic castration-resistant prostate cancer for whom cabazitaxel was considered the next appropriate standard treatment. Participants were required to have adequate renal, haematological, and liver function, and an Eastern Cooperative Oncology Group performance status of 0–2. Previous treatment with androgen receptor-directed therapy was allowed. Men underwent gallium-68 [68Ga]Ga-PSMA-11 and 2-flourine-18[18F]fluoro-2-deoxy-D-glucose (FDG) PET-CT scans. PET eligibility criteria for the trial were PSMA-positive disease, and no sites of metastatic disease with discordant FDG-positive and PSMA-negative findings. Men were randomly assigned (1:1) to [177Lu]Lu-PSMA-617 (6·0–8·5 GBq intravenously every 6 weeks for up to six cycles) or cabazitaxel (20 mg/m2 intravenously every 3 weeks for up to ten cycles). The primary endpoint was prostate-specific antigen (PSA) response defined by a reduction of at least 50% from baseline. This trial is registered with ClinicalTrials.gov, NCT03392428. Between Feb 6, 2018, and Sept 3, 2019, we screened 291 men, of whom 200 were eligible on PET imaging. Study treatment was received by 98 (99%) of 99 men randomly assigned to [177Lu]Lu-PSMA-617 versus 85 (84%) of 101 randomly assigned to cabazitaxel. PSA responses were more frequent among men in the [177Lu]Lu-PSMA-617 group than in the cabazitaxel group (65 vs 37 PSA responses; 66% vs 37% by intention to treat; difference 29% (95% CI 16–42; p<0·0001; and 66% vs 44% by treatment received; difference 23% [9–37]; p=0·0016). Grade 3–4 adverse events occurred in 32 (33%) of 98 men in the [177Lu]Lu-PSMA-617 group versus 45 (53%) of 85 men in the cabazitaxel group. No deaths were attributed to [177Lu]Lu-PSMA-617. [177Lu]Lu-PSMA-617 compared with cabazitaxel in men with metastatic castration-resistant prostate cancer led to a higher PSA response and fewer grade 3 or 4 adverse events. [177Lu]Lu-PSMA-617 is a new effective class of therapy and a potential alternative to cabazitaxel. Prostate Cancer Foundation of Australia, Endocyte (a Novartis company), Australian Nuclear Science and Technology Organization, Movember, The Distinguished Gentleman's Ride, It's a Bloke Thing, and CAN4CANCER.

Src kinase-mediated interactions between prostate cancer cells and osteoclasts might promote bone metastasis. Dasatinib inhibits tyrosine kinases, including Src kinases. Data suggests that dasatinib kinase inhibition leads to antitumour activity, affects osteoclasts, and has synergy with docetaxel, a first-line chemotherapy for metastatic castration-resistant prostate cancer. We assessed whether dasatinib plus docetaxel in chemotherapy-naive men with metastatic castration-resistant prostate cancer led to greater efficacy than with docetaxel alone. In this double-blind, randomised, placebo-controlled phase 3 study, we enrolled men of 18 years or older with chemotherapy-naive, metastatic, castration-resistant prostate cancer, and adequate organ function from 186 centres across 25 countries. Eligible patients were randomly assigned (1:1) via an interactive voice response system to receive docetaxel (75 mg/m2 intravenously every 3 weeks, plus oral prednisone 5 mg twice daily), plus either dasatinib (100 mg orally once daily) or placebo until disease progression or unacceptable toxicity. Randomisation was stratified by Eastern Cooperative Oncology Group performance status (0–1 vs 2), bisphosphonate use (yes vs no), and urinary N-telopeptide (uNTx) value (<60 μmol/mol creatinine vs ≥60 μmol/mol creatinine). All patients, investigators, and personnel involved in study conduct and data analyses were blinded to treatment allocation. The primary endpoint was overall survival, analysed by intention to treat. The trial is registered with ClinicalTrials.gov, number NCT00744497. Between Oct 30, 2008, and April 11, 2011, 1522 eligible patients were randomly assigned to treatment; 762 patients were assigned to dasatinib and 760 to placebo. At final analysis, median follow-up was 19·0 months (IQR 11·2–25·1) and 914 patients had died. Median overall survival was 21·5 months (95% CI 20·3–22·8) in the dasatinib group and 21·2 months (20·0–23·4) in the placebo group (stratified hazard ratio [HR] 0·99, 95·5% CI 0·87–1·13; p=0·90). The most common grade 3–4 adverse events included diarrhoea (58 [8%] patients in the dasatinib group vs 27 [4%] patients in the placebo group), fatigue (62 [8%] vs 42 [6%]), and asthenia (40 [5%] vs 23 [3%]); grade 3–4 pleural effusions were uncommon (ten [1%] vs three [<1%]). The addition of dasatinib to docetaxel did not improve overall survival for chemotherapy-naive men with metastatic castration-resistant prostate cancer. This study does not support the combination of dasatinib and docetaxel in this population of patients. Bristol-Myers Squibb.

Circulating tumor DNA (ctDNA) in plasma cell free DNA (cfDNA) of cancer patients is associated with poor prognosis, but is challenging to detect from low plasma volumes. In metastatic castration-resistant prostate cancer (mCRPC), ctDNA assays are needed to prognosticate outcomes of patients treated with androgen receptor (AR) inhibitors. We develop a custom targeted cfDNA sequencing assay, named AR -ctDETECT, to detect ctDNA in limiting plasma cfDNA available from mCRPC patients in the Alliance A031201 randomized phase 3 trial of enzalutamide with or without abiraterone. Of 776 patients, 59% are ctDNA-positive, with 26% having high ctDNA aneuploidy and 33% having low ctDNA aneuploidy but displaying AR gain or structural rearrangement, MYC / MYCN gain, or a pathogenic mutation. ctDNA-positive patients have significantly worse median overall survival than ctDNA-negative patients (29.0 months vs. 47.4 months, respectively). Here, we show that mCRPC patients identified as ctDNA-positive using the AR -ctDETECT assay have poor survival despite treatment with potent AR inhibitors in a phase 3 trial. Liquid biopsy assays are important to prognosticate outcomes of metastatic castration-resistant prostate cancer (mCRPC) patients treated with androgen receptor (AR) inhibitors. Here this group reports detecting circulating tumor DNA in limiting plasma cell-free DNA of mCRPC patients as prognostic marker of poor survival after AR treatment.

Background: Advanced prostate cancer is a phenotypically diverse disease that evolves through multiple clinical courses. PSA level is the most widely used parameter for disease monitoring, but it has well-recognized limitations. Unlike in clinical trials, in practice, clinicians may rely on PSA monitoring alone to determine disease status on therapy. This approach has not been adequately tested. Methods: Chemotherapy-naive asymptomatic or mildly symptomatic men ( n= 872) with metastatic castration-resistant prostate cancer (mCRPC) who were treated with the androgen receptor inhibitor enzalutamide in the PREVAIL study were analyzed post hoc for rising versus nonrising PSA (empirically defined as >1.05 vs ⩽1.05 times the PSA level from 3 months earlier) at the time of radiographic progression. Clinical characteristics and disease outcomes were compared between the rising and nonrising PSA groups. Results: Of 265 PREVAIL patients with radiographic progression and evaluable PSA levels on the enzalutamide arm, nearly one-quarter had a nonrising PSA. Median progression-free survival in this cohort was 8.3 months versus 11.1 months in the rising PSA cohort (hazard ratio 1.68; 95% confidence interval 1.26–2.23); overall survival was similar between the two groups, although less than half of patients in either group were still at risk at 24 months. Baseline clinical characteristics of the two groups were similar. Conclusions: Non-rising PSA at radiographic progression is a common phenomenon in mCRPC patients treated with enzalutamide. As restaging in advanced prostate cancer patients is often guided by increases in PSA levels, our results demonstrate that disease progression on enzalutamide can occur without rising PSA levels. Therefore, a disease monitoring strategy that includes imaging not entirely reliant on serial serum PSA measurement may more accurately identify disease progression.

Background and Objectives Oral enzalutamide (160 mg once daily) is approved for the treatment of metastatic castration-resistant prostate cancer (mCRPC). This article describes the pharmacokinetics of enzalutamide and its active metabolite N -desmethyl enzalutamide. Methods Results are reported from five clinical studies. Results In a dose-escalation study ( n  = 140), enzalutamide half-life was 5.8 days, steady state was achieved by day 28, accumulation was 8.3-fold, exposure was approximately dose proportional from 30–360 mg/day, and intersubject variability was ≤30 %. In a mass balance study ( n  = 6), enzalutamide was primarily eliminated by hepatic metabolism. Renal excretion was an insignificant elimination pathway for enzalutamide and N -desmethyl enzalutamide. In a food-effect study ( n  = 60), food did not have a meaningful effect on area under the plasma concentration–time curve (AUC) of enzalutamide or N -desmethyl enzalutamide, and in an hepatic impairment study, AUC of the sum of enzalutamide plus N -desmethyl enzalutamide was similar in men with mild ( n  = 6) or moderate ( n  = 8) impairment (Child–Pugh Class A and B) versus men with normal hepatic function ( n  = 14). In a phase III trial, an exposure-response analysis of steady-state predose (trough) concentrations ( C trough ) versus overall survival ( n  = 1103) showed that active treatment C trough quartiles for 160 mg/day were uniformly beneficial relative to placebo, and no threshold of C trough was associated with a statistically significant better response. Conclusions Enzalutamide has predictable pharmacokinetics, with low intersubject variability. Similar efficacy was observed in patients across the concentration/exposure range associated with a fixed oral dose of enzalutamide 160 mg/day.

We applied mathematical models to clinical trial data available at Project Data Sphere LLC (Cary, NC, USA), a non-profit universal access data-sharing warehouse. Our aim was to assess the rates of cancer growth and regression using the comparator groups of eight randomised clinical trials that enrolled patients with metastatic castration-resistant prostate cancer. In this retrospective analysis, we used data from eight randomised clinical trials with metastatic castration-resistant prostate cancer to estimate the growth (g) and regression (d) rates of disease burden over time. Rates were obtained by applying mathematical models to prostate-specific antigen levels as the representation of tumour quantity. Rates were compared between study interventions (prednisone, mitoxantrone, and docetaxel) and off-treatment data when on-study treatment had been discontinued to understand disease behaviour during treatment and after discontinuation. Growth (g) was examined for association with a traditional endpoint (overall survival) and for its potential use as an endpoint to reduce sample size in clinical trials. Estimates for g, d, or both were obtained in 2353 (88%) of 2678 patients with data available for analysis; g differentiated docetaxel (a US Food and Drug Administration-approved therapy) from prednisone and mitoxantrone and was predictive of overall survival in a landmark analysis at 8 months. A simulated sample size analysis, in which g was used as the endpoint, compared docetaxel data with mitoxantrone data and showed that small sample sizes were sufficient to achieve 80% power (16, 47, and 25 patients, respectively, in the three docetaxel comparator groups). Similar results were found when the mitoxantrone data were compared with the prednisone data (41, 39, and 41 patients in the three mitoxantrone comparator groups). Finally, after discontinuation of docetaxel therapy, median tumour growth (g) increased by nearly five times. The application of mathematical models to existing clinical data allowed estimation of rates of growth and regression that provided new insights in metastatic castration-resistant prostate cancer. The availability of clinical data through initiatives such as Project Data Sphere, when combined with innovative modelling techniques, could greatly enhance our understanding of how cancer responds to treatment, and accelerate the productivity of clinical development programmes. None.

Background Abiraterone is a 17α-hydroxylase/C17-20 lyase inhibitor used for the treatment of metastatic castration-resistant prostate cancer (CRPC). This multi-center, randomized, open-label, active-controlled phase II study compared the pharmacodynamics (PD), pharmacokinetics (PK), and safety of abiraterone acetate tablets (II) (AAT[II]), a new formulation of abiraterone acetate, and ZYTIGA®, the originator abiraterone acetate (OAA), in patients with metastatic CRPC. Methods Patients were randomized 1:1 to receive 300 mg AAT(II) daily plus 5 mg prednisone twice daily or 1000 mg OAA daily plus 5 mg prednisone twice daily for 84 days. The primary endpoint was the serum testosterone level (rounded-up) on Day 9 and/or Day 10. Absolute testosterone concentration, prostate-specific antigen (PSA) concentration, steady-state PK of abiraterone, and safety were also evaluated. Results Sixty-nine patients were enrolled in the study, with 35 assigned to AAT(II) and 34 to OAA. The least squares (LS) mean (standard error) of serum testosterone concentration (rounded-up) on Day 9 and/or Day 10 were 1.075 (0.034) and 1.000 (0.034) in the AAT(II) and OAA groups, respectively. The geometric mean ratio (AAT[II] vs. OAA) was 1.053 (90% confidence interval [CI], 0.998 to 1.110) and the LS mean difference was 0.075 (95% CI, -0.021 to 0.171). The 90% CI fell within the 80.0% to 125.0% equivalence limits, suggesting equivalent PD effect of the two formulations. AAT(II) also exhibited high testosterone inhibition rate (> 90% at all visits) and PSA-50 rate (> 65% on Days 56 and 84), which were comparable to that of OAA. AAT(II) also demonstrated an improved safety profile with lower incidence of adverse events compared to OAA. Conclusions AAT(II) at 300 mg plus prednisone demonstrated equivalent PD as OAA at 1000 mg plus prednisone in reducing serum testosterone on Day 9 and/or Day 10, and the effect was maintained up to the end of the study. Compared to OAA, AAT(II) was given at a much lower dosage and was not affected by food consumption. AAT(II) was well tolerated, and no new safety issues were found. Trial registration ClinicalTrials.gov, NCT04862091.

A novel cancer vaccine consisting of 20 mixed peptides (KRM-20) was designed to induce cytotoxic T lymphocytes (CTL) against twelve different tumor-associated antigens. The aim of this phase II trial was to examine whether KRM-20 in combination with docetaxel and dexamethasone enhances the antitumor effects in patients with castration-resistant prostate cancer (CRPC). In this double-blind, placebo-controlled, randomized phase II study, we enrolled chemotherapy-naïve patients with CRPC from ten medical centers in Japan. Eligible patients were randomly assigned 1:1 centrally to receive either KRM-20 combined with docetaxel and dexamethasone (n = 25) or placebo with docetaxel and dexamethasone (n = 26). The primary endpoint was the difference in prostate-specific antigen (PSA) decline between each treatment. The rates of > 50% PSA decline in the two arms were similar (56.5% versus 53.8%; P = 0.851). Human leukocyte antigen (HLA)-matched peptide-specific immunoglobulin G (P = 0.018) and CTL (P = 0.007) responses in the KRM-20 arm significantly increased after treatment. The addition of KRM-20 did not increase toxicity. There were no between-group differences in progression-free or overall survival (OS). The addition of KRM-20 was safe, and similar PSA decline and HLA-matched peptide-specific CTL and IgG responses increased in combination with docetaxel and dexamethasone in CRPC patients. Subgroup analysis suggested that this treatment is favorable for CRPC patients with ≥ 26% lymphocytes or PSA levels of < 11.2 ng/ml, but further clinical trials comparing OS are required.

Background: Biomarkers of therapeutic response and prognosis are needed to assist in the sequencing of treatments for metastatic castration-resistant prostate cancer (CRPC). Previously in a Phase 1 discovery study, we identified 14 circulating microRNAs that were associated with response to docetaxel chemotherapy or overall survival. We performed a Phase 2 validation study to verify these findings. Methods: Using real-time PCR, the levels of the 14 microRNAs were measured in plasma collected before and after the first cycle of docetaxel from a Phase 2 cohort of 89 patients. Results: The microRNAs were not associated with docetaxel response in the Phase 2 cohort. Higher baseline levels of six microRNAs, predominantly of the miR-200 family, were confirmed to be associated with shorter overall survival. A microRNA signature comprising these six microRNAs predicted high-risk patients in the Phase 2 cohort with a hazard ratio of 4.12 (95% CI 2.20–7.70, P =0.000001). The signature was an independent predictor in multivariable analysis with clinicopathological factors. Conclusions: The association of circulating microRNAs with overall survival suggests their involvement in CRPC progression.