Increased survival with enzalutamide in prostate cancer after chemotherapy.

BACKGROUND: Enzalutamide (formerly called MDV3100) targets multiple steps in the androgen-receptor-signaling pathway, the major driver of prostate-cancer growth. We aimed to evaluate whether enzalutamide prolongs survival in men with castration-resistant prostate cancer after chemotherapy. METHODS: In our phase 3, double-blind, placebo-controlled trial, we stratified 1199 men with castration-resistant prostate cancer after chemotherapy according to the Eastern Cooperative Oncology Group performance-status score and pain intensity. We randomly assigned them, in a 2:1 ratio, to receive oral enzalutamide at a dose of 160 mg per day (800 patients) or placebo (399 patients). The primary end point was overall survival. RESULTS: The study was stopped after a planned interim analysis at the time of 520 deaths. The median overall survival was 18.4 months (95% confidence interval [CI], 17.3 to not yet reached) in the enzalutamide group versus 13.6 months (95% CI, 11.3 to 15.8) in the placebo group (hazard ratio for death in the enzalutamide group, 0.63; 95% CI, 0.53 to 0.75; P<0.001). The superiority of enzalutamide over placebo was shown with respect to all secondary end points: the proportion of patients with a reduction in the prostate-specific antigen (PSA) level by 50% or more (54% vs. 2%, P<0.001), the soft-tissue response rate (29% vs. 4%, P<0.001), the quality-of-life response rate (43% vs. 18%, P<0.001), the time to PSA progression (8.3 vs. 3.0 months; hazard ratio, 0.25; P<0.001), radiographic progression-free survival (8.3 vs. 2.9 months; hazard ratio, 0.40; P<0.001), and the time to the first skeletal-related event (16.7 vs. 13.3 months; hazard ratio, 0.69; P<0.001). Rates of fatigue, diarrhea, and hot flashes were higher in the enzalutamide group. Seizures were reported in five patients (0.6%) receiving enzalutamide. CONCLUSIONS: Enzalutamide significantly prolonged the survival of men with metastatic castration-resistant prostate cancer after chemotherapy. (Funded by Medivation and Astellas Pharma Global Development; AFFIRM ClinicalTrials.gov number, NCT00974311.).

Antitumour activity of MDV3100 in castration-resistant prostate cancer: a phase 1-2 study.

BACKGROUND: MDV3100 is an androgen-receptor antagonist that blocks androgens from binding to the androgen receptor and prevents nuclear translocation and co-activator recruitment of the ligand-receptor complex. It also induces tumour cell apoptosis, and has no agonist activity. Because growth of castration-resistant prostate cancer is dependent on continued androgen-receptor signalling, we assessed the antitumour activity and safety of MDV3100 in men with this disease. METHODS: This phase 1-2 study was undertaken in five US centres in 140 patients. Patients with progressive, metastatic, castration-resistant prostate cancer were enrolled in dose-escalation cohorts of three to six patients and given an oral daily starting dose of MDV3100 30 mg. The final daily doses studied were 30 mg (n=3), 60 mg (27), 150 mg (28), 240 mg (29), 360 mg (28), 480 mg (22), and 600 mg (3). The primary objective was to identify the safety and tolerability profile of MDV3100 and to establish the maximum tolerated dose. The trial is registered with ClinicalTrials.gov, number NCT00510718. FINDINGS: We noted antitumour effects at all doses, including decreases in serum prostate-specific antigen of 50% or more in 78 (56%) patients, responses in soft tissue in 13 (22%) of 59 patients, stabilised bone disease in 61 (56%) of 109 patients, and conversion from unfavourable to favourable circulating tumour cell counts in 25 (49%) of the 51 patients. PET imaging of 22 patients to assess androgen-receptor blockade showed decreased (18)F-fluoro-5alpha-dihydrotestosterone binding at doses from 60 mg to 480 mg per day (range 20-100%). The median time to progression was 47 weeks (95% CI 34-not reached) for radiological progression. The maximum tolerated dose for sustained treatment (>28 days) was 240 mg. The most common grade 3-4 adverse event was dose-dependent fatigue (16 [11%] patients), which generally resolved after dose reduction. INTERPRETATION: We recorded encouraging antitumour activity with MDV3100 in patients with castration-resistant prostate cancer. The results of this phase 1-2 trial validate in man preclinical studies implicating sustained androgen-receptor signalling as a driver in this disease. FUNDING: Medivation, the Prostate Cancer Foundation, National Cancer Institute, the Howard Hughes Medical Institute, Doris Duke Charitable Foundation, and Department of Defense Prostate Cancer Clinical Trials Consortium.

A randomized, placebo-controlled trial of latrepirdine in Huntington disease.

OBJECTIVES: To evaluate the safety and tolerability of latrepirdine in Huntington disease (HD) and explore its effects on cognition, behavior, and motor symptoms. DESIGN: Double-blind, randomized, placebo-controlled trial. SETTING: Multicenter outpatient trial. PARTICIPANTS: Ninety-one participants with mild to moderate HD enrolled at 17 US and UK centers from July 18, 2007, through July 16, 2008. INTERVENTION: Latrepirdine, 20 mg 3 times daily (n = 46), or matching placebo (n = 45) for a 90-day treatment period. MAIN OUTCOME MEASURES: The primary outcome variable was tolerability, defined as the ability to complete the study at the assigned drug dosage. Secondary outcome variables included score changes from baseline to day 90 on the Unified Huntington's Disease Rating Scale (UHDRS), the Mini-Mental State Examination (MMSE), and the Alzheimer Disease Assessment Scale-cognitive subscale (ADAS-cog). RESULTS: Latrepirdine was well tolerated (87% of the patients given latrepirdine completed the study vs 82% in the placebo group), and adverse event rates were comparable in the 2 groups (70% in the latrepirdine group and 80% in the placebo group). Treatment with latrepirdine resulted in improved mean MMSE scores compared with stable performance in the placebo group (treatment effect, 0.97 points; 95% confidence interval, 0.10-1.85; P = .03). No significant treatment effects were seen on the UHDRS or the ADAS-cog. CONCLUSIONS: Short-term administration of latrepirdine is well tolerated in patients with HD and may have a beneficial effect on cognition. Further investigation of latrepirdine is warranted in this population with HD.

Effect of dimebon on cognition, activities of daily living, behaviour, and global function in patients with mild-to-moderate Alzheimer's disease: a randomised, double-blind, placebo-controlled study.

BACKGROUND: Although treatments for Alzheimer's disease sometimes improve cognition, functional ability, or behaviour compared with baseline levels, such improvements are inconsistent across studies and measures, and effects diminish over time. More effective treatments are needed. We assessed the safety, tolerability, and efficacy of dimebon in the treatment of patients with mild-to-moderate Alzheimer's disease. METHODS: We enrolled 183 patients with mild-to-moderate Alzheimer's disease (mini-mental state examination [MMSE] scores 10-24) at 11 sites in Russia. Patients were randomly assigned by a computer-generated randomisation scheme to receive oral dimebon, 20 mg three times a day (60 mg/day [n=89]), or matched placebo (n=94). Other antidementia drugs were not allowed. The primary outcome measure assessed cognition, the difference in mean change from baseline to week 26, or last completed observation on the cognitive subscale of the Alzheimer's disease assessment scale (ADAS-cog). All patients and study personnel were blinded throughout the study. We compared dimebon with placebo with an intention-to-treat analysis, with last observation carried forward (ITT-LOCF) imputation. Analyses were repeated on the fully evaluable population, defined as all patients in the intention-to-treat population who had an ADAS-cog at week 26 and at least 80% compliance. 134 patients (68 in dimebon group, 66 in placebo group) enrolled in the 6-month blinded extension phase of the study. This trial is registered with Clinicaltrials.gov, number NCT00377715. FINDINGS: 155 (85%) patients completed the trial (78 [88%] in dimebon group, 77 [82%] in placebo group). Treatment with dimebon resulted in significant benefits in ADAS-cog compared with placebo (ITT-LOCF) at week 26 (mean drug-placebo difference -4.0 [95% CI -5.73 to -2.28]; p<0.0001). Results of the ITT-LOCF and the evaluable population analyses were much the same for all measures. Patients given dimebon were significantly improved over baseline for ADAS-cog (mean difference -1.9 [-2.92 to -0.85]; p=0.0005). Dimebon was well tolerated: dry mouth and depressed mood or depression were the most common adverse events associated with dimebon (12 [14%] patients for each symptom by week 26). The percentage of patients who had adverse events in the two groups did not differ. INTERPRETATION: Dimebon was safe, well tolerated, and significantly improved the clinical course of patients with mild-to-moderate Alzheimer's disease.

Results of PREVENT III: a multicenter, randomized trial of edifoligide for the prevention of vein graft failure in lower extremity bypass surgery.

OBJECTIVE: The PREVENT III study was a prospective, randomized, double-blinded, multicenter phase III trial of a novel molecular therapy (edifoligide; E2F decoy) for the prevention of vein graft failure in patients undergoing infrainguinal revascularization for critical limb ischemia (CLI). METHODS: From November 2001 through October 2003, 1404 patients with CLI were randomized to a single intraoperative ex vivo vein graft treatment with edifoligide or placebo. After surgery, patients underwent graft surveillance by duplex ultrasonography and were followed up for index graft and limb end points to 1 year. A blinded Clinical Events Classification committee reviewed all index graft end points. The primary study end point was the time to nontechnical index graft reintervention or major amputation due to index graft failure. Secondary end points included all-cause graft failure, clinically significant graft stenosis (>70% by angiography or severe stenosis by ultrasonography), amputation/reintervention-free survival, and nontechnical primary graft patency. Event rates were based on Kaplan-Meier estimates. Time-to-event end points were compared by using the log-rank test. RESULTS: Demographics, comorbidities, and procedural details reflected a population with CLI and diffuse atherosclerosis. Tissue loss was the presenting symptom in 75% of patients. High-risk conduits were used in 24% of cases, including an alternative vein in 20% (15% spliced vein and 5% non-great saphenous vein) and 6% less than 3 mm in diameter; 14% of the cases were reoperative bypass grafts. Most (65%) grafts were placed to infrapopliteal targets. Perioperative (30-day) mortality occurred in 2.7% of patients. Major morbidity included myocardial infarction in 4.7% and early graft occlusion in 5.2% of patients. Ex vivo treatment with edifoligide was well tolerated. There was no significant difference between the treatment groups in the primary or secondary trial end points, primary graft patency, or limb salvage. A statistically significant improvement was observed in secondary graft patency (estimated Kaplan-Meier rates were 83% edifoligide and 78% placebo; P = .016) within 1 year. The reduction in secondary patency events was manifest within 30 days of surgery (the relative risk for a 30-day event for edifoligide was 0.45; 95% confidence interval, 0.27-0.76; P = .005). For the overall cohort at 1 year, the estimated Kaplan-Meier rate for survival was 84%, that for primary patency was 61%, that for primary assisted patency was 77%, that for secondary patency was 80%, and that for limb salvage was 88%. CONCLUSIONS: In this prospective, randomized, placebo-controlled clinical trial, ex vivo treatment of lower extremity vein grafts with edifoligide did not confer protection from reintervention for graft failure.

Risk factors, medical therapies and perioperative events in limb salvage surgery: observations from the PREVENT III multicenter trial.

OBJECTIVES: Patients who require infrainguinal revascularization for critical limb ischemia (CLI) are at elevated risk for cardiovascular events. The PREVENT III study was a prospective, randomized, multicenter, phase 3 trial of edifoligide for the prevention of vein graft failure in patients with CLI. We examined the baseline characteristics, perioperative medical therapies, and 30-day incidence of major cardiovascular events in the PREVENT III cohort. METHODS: Demographics, medical and surgical history, mode of presentation for the index limb, procedural details, and concomitant medications were reviewed for all patients enrolled in PREVENT III (N = 1,404). Major adverse cardiovascular events, including death, myocardial infarction, or cerebrovascular event (stroke or transient ischemic attack) were tabulated. Univariate and multivariate analyses were performed to discern factors that were associated with the utilization of medical therapies and with perioperative events. RESULTS: Demographics and comorbidities reflected a population with diffuse, advanced atherosclerosis. Perioperative mortality was 2.7%, and major morbidity included myocardial infarction in 4.7% and stroke/transient ischemic attack in 1.4%. Among this population of CLI patients, 33% were not on antiplatelet therapy at study entry, and 24% were not receiving antithrombotics of any type. In addition, 54% of patients were not receiving lipid-lowering therapy, and 52% were not prescribed beta-blocker medications at study entry. On multivariate analysis, race was a significant determinant of antithrombotic utilization, with African-American patients less frequently treated both at baseline and discharge (adjusted odd ratios, 0.5 and 0.6, P < .0001). Antithrombotic and beta-blocker drug usage increased in the overall cohort from baseline (76% and 48%) to discharge (88% and 60%; P < .0001). Patients treated in a university hospital setting were more likely to be prescribed antiplatelet, lipid-lowering, and beta-blocker medications. Advanced age (>75 years), coronary artery disease (prior myocardial infarction or revascularization), and dialysis-dependent renal failure were associated with an increased 30-day risk of death, myocardial infarction, or stroke. Protective effects of beta-blocker and lipid-lowering medications were noted in these defined subgroups. CONCLUSIONS: A significant percentage of the population that undergoes surgical revascularization for CLI is not prescribed therapies of proven benefit in reducing cardiovascular events. Utilization of antithrombotics and beta-blockers increases during hospitalization for limb salvage surgery but that of lipid-lowering therapy does not. African-American patients appear to be at greater risk for undertreatment with antithrombotics, and the data suggest that patients undergoing leg bypass surgery in a university hospital setting receive more comprehensive medical treatment of atherosclerosis. Treatment guidelines for medical therapy are needed to standardize care and improve outcomes for patients with CLI.