A Flexible Ensemble Learning Method for Survival Extrapolation.

OBJECTIVES: Survival extrapolation is an important statistical concept for estimating long-term survival from short-term clinical trial data. It is widely used in health technology assessment (HTA). Survival extrapolation is often performed by fitting one or two parametric models selected based on experience or selecting a model based on some goodness of fit statistics from a predefined collection of models. The main challenge in survival extrapolation is that the result is sensitive to model misspecification. In this study, we aim to propose a new approach that has a robust performance for survival extrapolation. METHODS: We propose a new method called Ensemble Learning for Survival Extrapolation (ELSE). Instead of selecting one best model from a predefined collection, ELSE builds an ensemble model based on a collection of models from the model library. Under this framework, we construct a point estimate of the long-term survival with a weighted average of the estimates of all candidate models and derive confidence intervals using nonparametric bootstrap. RESULTS: With our extensive numerical simulation studies, the proposed ELSE method shows better performance than the traditionally used model selection procedure based on Akaike Information Criterion (AIC). With a real data application to the Therapeutically Applicable Research to Generate Effective Treatment Wilms Tumor project (TARGET-WT) data, the ELSE method produces better survival extrapolation results in point estimate accuracy and confidence interval coverage. CONCLUSIONS: We developed an ensemble learning method for survival extrapolation (ELSE) which is robust for the underline data model and has good real data performance.

Endometriosis-Related Pain Reduction During Bleeding and Nonbleeding Days in Women Treated with Elagolix.

OBJECTIVE: In this post hoc analysis, we evaluated the impact of elagolix on dysmenorrhea and nonmenstrual pelvic pain across menstrual period (bleeding days) and nonmenstrual (nonbleeding) days. METHODS: Data from two randomized, 6-month, placebo-controlled trials (Elaris Endometriosis (EM)-I and EM-II) of elagolix (150 mg once daily (QD) and 200 mg twice daily (BID)) in premenopausal women with moderate to severe endometriosis-associated pain (N = 1686) were pooled. Women recorded the presence of menstrual period and severity of dysmenorrhea or nonmenstrual pelvic pain in a daily electronic diary. RESULTS: At baseline, women in the placebo group and both elagolix treatment groups reported moderate or severe dysmenorrhea, on average, 81% of their menstrual period days and moderate/severe nonmenstrual pelvic pain, on average, 56% of their nonmenstrual (nonbleeding) days. Compared with placebo at month 6, elagolix-treated women had a significantly lower mean (standard deviation (SD)) percentage of menstrual period days with moderate or severe dysmenorrhea (elagolix 150 mg QD = 52.4 (38.9), p = 0.002; elagolix 200 mg BID = 38.5 (43.6), p < 0.001, placebo = 61.3 (33.7)) and a significantly lower mean (SD) percentage of nonmenstrual (nonbleeding) days with moderate or severe nonmenstrual pelvic pain (elagolix 150 mg QD = 31.1 (35.8), p < 0.001; elagolix 200 mg BID = 19.7 (29.9), p < 0.001; placebo = 35.6 (33.9)). CONCLUSION: Following 6 months of elagolix treatment, women who still menstruated had a lower proportion of menstrual period days with moderate or severe dysmenorrhea compared with placebo, demonstrating pain reduction despite continued menses. Additionally, pain did not shift from dysmenorrhea to nonmenstrual pelvic pain, as the percentage of days with moderate or severe nonmenstrual pelvic pain was also reduced for elagolix-treated women compared with placebo. TRIAL REGISTRATION: The Elaris EM-I study is registered with the US National Library of Medicine, www.ClinicalTrials.gov, NCT01620528. The Elaris EM-II study is registered with the US National Library of Medicine, www.ClinicalTrials.gov, NCT01931670. Both studies are registered with the EU Clinical Trial Register, www.clinicaltrialsregister.ed, 2011-004295-11.

Health-Related Quality-of-Life Analysis From KEYNOTE-045: A Phase III Study of Pembrolizumab Versus Chemotherapy for Previously Treated Advanced Urothelial Cancer.

Purpose In the phase III KEYNOTE-045 study ( ClinicalTrials.gov identifier: NCT02256436), pembrolizumab significantly prolonged overall survival compared with investigator's choice of chemotherapy in patients with previously treated advanced urothelial cancer. Here, we report the results of health-related quality-of-life (HRQoL) analyses from the KEYNOTE-045 trial. Patients and Methods Patients were randomly assigned 1:1 to pembrolizumab 200 mg or investigator's choice of docetaxel 75 mg/m2, paclitaxel 175 mg/m2, or vinflunine 320 mg/m2 administered intravenously every 3 weeks. Key prespecified HRQoL analyses were time to deterioration (TTD) and mean change from baseline to week 15 in European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire C30 global health status/quality-of-life score. Results Of 542 patients who were randomly assigned, 519 were included in HRQoL analyses (pembrolizumab, n = 266; chemotherapy, n = 253). HRQoL compliance was > 95% at baseline and approximately 88% at week 15 for both groups. Pembrolizumab prolonged TTD in global health status/quality-of-life score compared with chemotherapy (median, 3.5 months v 2.3 months; hazard ratio, 0.72; nominal one-sided P = .004). Mean (95% CI) change from baseline to week 15 in global health status/quality-of-life score was 0.69 (-2.40 to 3.77) with pembrolizumab and -8.36 (-11.84 to -4.89) with chemotherapy (mean difference, 9.05 points; 95% CI, 4.61 to 13.50; nominal two-sided P < .001). Conclusion Pembrolizumab prolonged TTD in HRQoL compared with chemotherapy. Patients who were treated with pembrolizumab had stable or improved global health status/quality of life, whereas those who were treated with investigator's choice of chemotherapy experienced declines in global health status/quality of life. Combined with efficacy and safety outcomes, these data support pembrolizumab as standard of care for patients with platinum-refractory advanced urothelial cancer.

Pembrolizumab as Second-Line Therapy for Advanced Urothelial Carcinoma.

BACKGROUND: Patients with advanced urothelial carcinoma that progresses after platinum-based chemotherapy have a poor prognosis and limited treatment options. METHODS: In this open-label, international, phase 3 trial, we randomly assigned 542 patients with advanced urothelial cancer that recurred or progressed after platinum-based chemotherapy to receive pembrolizumab (a highly selective, humanized monoclonal IgG4κ isotype antibody against programmed death 1 [PD-1]) at a dose of 200 mg every 3 weeks or the investigator's choice of chemotherapy with paclitaxel, docetaxel, or vinflunine. The coprimary end points were overall survival and progression-free survival, which were assessed among all patients and among patients who had a tumor PD-1 ligand (PD-L1) combined positive score (the percentage of PD-L1-expressing tumor and infiltrating immune cells relative to the total number of tumor cells) of 10% or more. RESULTS: The median overall survival in the total population was 10.3 months (95% confidence interval [CI], 8.0 to 11.8) in the pembrolizumab group, as compared with 7.4 months (95% CI, 6.1 to 8.3) in the chemotherapy group (hazard ratio for death, 0.73; 95% CI, 0.59 to 0.91; P=0.002). The median overall survival among patients who had a tumor PD-L1 combined positive score of 10% or more was 8.0 months (95% CI, 5.0 to 12.3) in the pembrolizumab group, as compared with 5.2 months (95% CI, 4.0 to 7.4) in the chemotherapy group (hazard ratio, 0.57; 95% CI, 0.37 to 0.88; P=0.005). There was no significant between-group difference in the duration of progression-free survival in the total population (hazard ratio for death or disease progression, 0.98; 95% CI, 0.81 to 1.19; P=0.42) or among patients who had a tumor PD-L1 combined positive score of 10% or more (hazard ratio, 0.89; 95% CI, 0.61 to 1.28; P=0.24). Fewer treatment-related adverse events of any grade were reported in the pembrolizumab group than in the chemotherapy group (60.9% vs. 90.2%); there were also fewer events of grade 3, 4, or 5 severity reported in the pembrolizumab group than in the chemotherapy group (15.0% vs. 49.4%). CONCLUSIONS: Pembrolizumab was associated with significantly longer overall survival (by approximately 3 months) and with a lower rate of treatment-related adverse events than chemotherapy as second-line therapy for platinum-refractory advanced urothelial carcinoma. (Funded by Merck; KEYNOTE-045 ClinicalTrials.gov number, NCT02256436 .).

Effect of angiotensin receptor blockade on insulin sensitivity and endothelial function in abdominally obese hypertensive patients with impaired fasting glucose.

AngII (angiotensin II) may contribute to cardiovascular risk in obesity via adverse effects on insulin sensitivity and endothelial function. In the present study, we examined the effects of ARB (angiotensin receptor blocker) therapy (losartan, 100 mg/day) on insulin sensitivity and endothelial function in 53 subjects with stage I hypertension, abdominal obesity and impaired fasting glucose. The study design was a randomized double-blinded parallel design placebo-controlled multi-centre trial of 8 weeks duration. We used the hyperinsulinaemic-euglycaemic clamp technique to measure insulin sensitivity (expressed as the 'M/I' value) and RH-PAT (reactive hyperaemia-peripheral arterial tonometry) to measure endothelial function. Additional measures included HOMA (homoeostasis model assessment)-B, an index of pancreatic ß-cell function, and markers of inflammation [e.g. CRP (C-reactive protein)] and oxidative stress (e.g. F2-isoprostanes). ARB therapy did not alter insulin sensitivity [5.2 (2.7) pre-treatment and 4.6 (1.6) post-treatment] compared with placebo therapy [6.1 (2.9) pre-treatment and 5.3 (2.7) post-treatment; P value not significant], but did improve the HOMA-B compared with placebo therapy (P=0.05). ARB therapy also did not change endothelial function [RH-PAT, 2.15 (0.7) pre-treatment and 2.11 (0.7) post-treatment] compared with placebo therapy [RH-PAT, 1.81 (0.5) pre-treatment and 1.76 (0.7) post-treatment; P value not significant]. Markers of inflammation and oxidative stress were not significantly changed by ARB therapy. In conclusion, ARB therapy did not alter peripheral insulin sensitivity or endothelial function in this cohort of patients with essential hypertension, abdominal obesity and impaired fasting glucose, but did improve pancreatic ß-cell function.

Effects of the renin inhibitor MK-8141 (ACT-077825) in patients with hypertension.

The renin inhibitor MK-8141 (ACT-077825) demonstrates substantial immunoreactive active renin (ir-AR) increase (sevenfold) without a persistent plasma renin activity (PRA) decrease. The present study assessed the antihypertensive efficacy of MK-8141 in hypertensive patients. In this double-blind, placebo- and active comparator-controlled study, 195 patients with hypertension (trough sitting diastolic blood pressure ≥92 to <105 mm Hg, trough sitting systolic blood pressure <170 mm Hg, and 24-hour mean diastolic blood pressure [DBP] ≥80 mm Hg) were randomized to one of four treatments (stratified by race, black versus others): MK-8141 250 mg, MK-8141 500 mg, enalapril 20 mg, or placebo. Blood pressure was measured at trough and as 24-hour ambulatory blood pressure monitoring. The primary end point was change from baseline in 24-hour mean ambulatory DBP measured after 4 weeks. At week 4, the change from baseline in 24-hour mean (95% CI) ambulatory DBP compared with placebo was -1.6 mm Hg (-4.2, 1.1), -1.1 mm Hg (-3.9, 1.6), and -4.9 (-7.5, -2.2) for MK-8141 250 mg, MK-8141 500 mg, and enalapril 20 mg, respectively. Only mean ambulatory DBP-lowering with enalapril 20 mg was statistically significant. Enalapril, but not MK-8141, also significantly lowered 24-hour mean ambulatory systolic blood pressure (SBP) compared with placebo (-6.7 mm Hg [-10.5, -2.8]). Neither enalapril nor MK-8141 significantly lowered trough DBP and SBP compared with placebo. MK-8141 was generally well tolerated. In patients with hypertension, MK-8141 (ACT-077825) did not produce significant blood pressure-lowering efficacy despite a demonstrated effect of the drug on ir-AR, in the absence of durable PRA suppression.