Considerations in Genomic Therapy Matching-Reply.
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Journal Article↗
Biomedical subjects
John Simes
Publications and source records attributed to John Simes.
Older adults with resectable gastric cancer undergoing perioperative chemotherapy or preoperative chemoradiotherapy plus perioperative chemotherapy: A secondary analysis of the AGITG TOPGEAR phase III trial.
PURPOSE: To evaluate treatment adherence, adverse events, and survival in older (≥70 years) adults undergoing perioperative treatment for gastric cancer. METHODS: Patients with resectable gastric/gastro-esophageal junction adenocarcinoma (ECOG 0-1) enrolled in the phase III TOPGEAR trial were randomized to perioperative chemotherapy (ECF/ECX or FLOT) alone or perioperative chemotherapy plus preoperative chemoradiotherapy (45 Gy in 25 fractions with concurrent fluoropyrimidine). In this exploratory analysis, treatment completion, grade ≥ 3 adverse events (CTCAE v3.0), surgical outcomes, overall survival (OS) and progression-free survival (PFS) were compared between older and younger adults. RESULTS: Of the 574 patients enrolled, 135 (24%) were ≥ 70 years. Older adults more frequently required preoperative chemotherapy dose reductions, omissions, or delays (chemoradiotherapy: 55% vs 35%, p = 0.004; chemotherapy: 60% vs 48%, p = 0.087). Rates of grade ≥ 3 adverse events were comparable between older and younger patients (chemoradiotherapy: 66% vs 67%, p = 0.874; chemotherapy: 68% vs 59%, p = 0.220), but older adults more often had hematologic toxicity and grade ≥ 3 diarrhea in the chemotherapy group (56% vs 37%, p = 0.006; 21% vs 6%, p < 0.001). Resection rates, grade 3/4 surgical complications, number of removed lymph nodes, and 30-/90-day mortality were similar by age. OS and PFS were comparable across age groups, with numerically favorable outcomes for older adults (OS: HR 0.86, 95% CI 0.58-1.26 [chemoradiotherapy]; HR 0.75, 95% CI 0.51-1.11 [chemotherapy]; PFS: HR 0.78, 95% CI 0.53-1.15 [chemoradiotherapy]; HR 0.70, 95% CI 0.47-1.03 [chemotherapy]). CONCLUSIONS: Older adults with gastric cancer achieved comparable oncologic outcomes to younger patients, despite more frequent treatment modifications and higher hematologic toxicity.
Humans↗
Correction to the FIELD study report.
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Letter↗
Predicting toxicities for patients with advanced gastrointestinal stromal tumours treated with imatinib: a study of the European Organisation for Research and Treatment of Cancer, the Italian Sarcoma Group, and the Australasian Gastro-Intestinal Trials Group (EORTC-ISG-AGITG).
The aim of this study was to identify prognostic factors for toxicity to treatment with imatinib. The study was based on 942 patients with gastrointestinal stromal tumours (GIST) randomised to receive imatinib at different doses. The correlation between toxicities occurring with a Common Toxicity Criteria (CTC) grade 2 or more (non-haematological) or grade 3 or 4 (haematological) and imatinib dose, age, sex, performance status, original disease site, site and size of lesions at trial entry, baseline haematological and biological parameters was investigated. Anaemia was correlated with dose and baseline haemoglobin level, and neutropaenia with baseline neutrophil count and haemoglobin level. The risk of non-haematological toxicities was dose dependent and higher in females (oedema, nausea, diarrhoea), and in patients of advanced age (oedema, rash fatigue), poor performance status (fatigue and nausea), prior chemotherapy (fatigue), tumour of identified gastrointestinal origin (diarrhoea) and small lesions (rash). A multivariate risk calculator that can be used in the clinic for individual patients is proposed.
Adult↗
Missing data methods for the assessment of surrogate outcomes and treatment mechanisms in clinical trial substudies.
Hypotheses about the mechanisms of action by which a treatment affects a clinical outcome may prompt consideration of an alternative outcome as a potential surrogate. In many cases, due to costs or other factors, the candidate for surrogacy will only be measured for patients randomized to a substudy within the main trial. In this situation, the substudy patients provide information about links between the true and surrogate outcomes and the treatment, and these links can be exploited, using methods for handling missing covariates, to allow available information for patients not in the substudy to be incorporated into the analysis. The increased precision with which the treatment effect can be estimated using these methods, compared with using substudy data alone, in turn allows more precise estimates of measures of surrogacy. This paper reviews and compares some methods for handling missing covariate data and applies the methodology to a large heart attack trial, in order to investigate the properties of four measures for assessing the extent to which early response to thrombolytic therapy, as measured by an improvement in coronary blood flow, can be regarded as a surrogate for 30-day survival following heart attack. Design issues for substudies intended to assess treatment mechanisms are also considered. In particular, we consider how the precision of surrogate measures varies with the size of the substudy relative to the main trial. The results suggest that for reasonable surrogates, substudies substantially smaller than the main study can extract most of the available information regarding surrogacy.
Biomarkers↗
Outcomes of patients in clinical trials with ST-segment elevation myocardial infarction among countries with different gross national incomes.
AIMS: To evaluate whether there is an association between 30-day mortality in patients with ST-segment elevation myocardial infarction (STEMI) included in clinical trials and country gross national income (GNI). METHODS AND RESULTS: A retrospective analysis of the databases of five randomized trials including 50 310 patients with STEMI (COBALT 7169, GIK-2 2931, HERO-2 17,089, ASSENT-2 17,005, and ASSENT-3 6116 patients) from 53 countries was performed. Countries were divided into three groups according to their GNI based on the World Bank data: low (less than 2900 US dollars), medium (between 2900 US dollars and 9000 US dollars), and high GNI (more than 9000 US dollars per capita). Baseline characteristics, in-hospital management variables, and 30-day outcomes were evaluated. A previously defined logistic regression model was used to adjust for differences in baseline characteristics and to predict mortality. The observed mortality was higher than the predicted mortality in the low (12.1 vs. 11.8%) and in the medium income groups (9.4 vs. 7.9%), whereas it was lower in the high income group (4.9 vs. 5.6%). CONCLUSION: An inverse relationship between mortality and GNI was observed in STEMI clinical trials. Most of the variability in mortality can be explained by differences in baseline characteristics; however, after adjustment, lower income countries have higher mortality than the expected.
Female↗
Survival effects of postmastectomy adjuvant radiation therapy using biologically equivalent doses: a clinical perspective.
BACKGROUND: Postmastectomy radiation therapy reduces locoregional recurrence among women with operable breast cancer, but whether it improves survival has been controversial. We reanalyzed the results from 36 unconfounded trials (i.e., addition of radiation therapy was the sole discriminant between treatments being compared) that were identified in previous meta-analyses, which provided 38 comparisons. METHODS: We used three predefined treatment categories for individual patient data: 1) a biologically equivalent dose (BED) of 40-60 Gy in 2-Gy fractions with an appropriate target volume, 2) an inadequate or excessive dose of radiation therapy, and 3) an inappropriate target volume. Effects of radiation therapy on 5-year and 10-year survival in each of the treatment categories were estimated from a cohort of 13 199 patients from the published rates or, if these were unavailable, from the published survival curves. We also used this categorization to reanalyze data from Early Breast Cancer Trialists' Collaborative Group (EBCTCG) postmastectomy studies. At 10 years, 16 (84%) of the 19 comparisons in our study coincided with those reported by the EBCTCG. All statistical tests were two-sided. RESULTS: Twenty-five of the 38 available comparisons had used optimal and complete radiotherapy (i.e., category 1). Of these 25 comparisons, 17 had 5-year data, and these data showed that adjuvant radiation therapy was associated with a 2.9% absolute increase in survival (odds ratio [OR] of death = 0.87, 95% confidence interval [CI] = 0.79 to 0.96; P = .006). Thirteen category 1 trials had data at 10 years, and these data showed that adjuvant radiation therapy was associated with a statistically significant 6.4% absolute increase in survival (OR of death = 0.78, 95% CI = 0.70 to 0.85; P < .001). No statistically significant change in survival was observed among category 2 (OR of death = 0.91, 95% CI = 0.75 to 1.11) or 3 (OR of death = 0.97, 95% CI = 0.61 to 1.55) trials. Among the 33 EBCTCG studies, odds of local recurrence were reduced more among category 1 trials (80% lower) than among category 2 (70% lower) or 3 (64% lower) trials (P(heterogeneity) < .001). Odds of all-cause death were also lower among category 1 trials (13% lower) than among category 2 (3% lower) or 3 (26% higher) trials (P(heterogeneity) = .01). CONCLUSIONS: Adjuvant radiation therapy with an optimal BED and target volume was statistically significantly associated with improved survival for up to 10 years.
Breast Neoplasms↗
Cost-effectiveness of cholesterol-lowering therapy with pravastatin in patients with previous acute coronary syndromes aged 65 to 74 years compared with younger patients: results from the LIPID study.
BACKGROUND: We compared cost-effectiveness of pravastatin in a placebo-controlled trial in 5500 younger (31-64 years) and 3514 older patients (65-74 years) with previous acute coronary syndromes. METHODS: Hospitalizations and long-term medication within the 6 years of the trial were estimated in all patients . Drug dosage, nursing home, and ambulatory care costs were estimated from substudies. Incremental costs per life saved of pravastatin relative to placebo were estimated from treatment effects and resource use. RESULTS: Over 6 years, pravastatin reduced all-cause mortality by 4.3% in the older patients and by 2.3% in the younger patients. Older patients assigned pravastatin had marginally lower cost of pravastatin and other medication over 6 years (A dollar 4442 vs A dollar 4637), but greater cost offsets (A dollar 2061 vs A dollar 897) from lower rates of hospitalizations. The incremental cost per life saved with pravastatin was A dollar 55500 in the old and A dollar 167200 in the young. Assuming no treatment effect beyond the study period, the life expectancy to age 82 years of additional survivors was 9.1 years in the older and 17.3 years in the younger. Estimated additional life-years saved from pravastatin therapy were 0.39 years for older and 0.40 years for younger patients. Incremental costs per life-year saved were A dollar 7581 in the older and A dollar 14944 in the younger, if discounted at 5% per annum. CONCLUSIONS: Pravastatin therapy was more cost-effective among older than younger patients, because of their higher baseline risk and greater cost offsets, despite their shorter life expectancy.
Acute Disease↗
Prospective registration of clinical trials.
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Clinical Trials as Topic↗
Effect of pravastatin in people with diabetes and chronic kidney disease.
Although diabetes is a major cause of chronic kidney disease (CKD), limited data describe the cardiovascular benefit of hydroxymethyl glutaryl CoA reductase inhibitors (statins) in people with both of these conditions. This study sought to determine whether pravastatin reduced the incidence of first or recurrent cardiovascular events in people with non-dialysis-dependent CKD and concomitant diabetes, using data from three randomized trials of pravastatin 40 mg daily versus placebo. CKD was defined by estimated GFR <60 or 60 to 89.9 ml/min per 1.73 m2 with proteinuria. Of 19,737 patients, 4099 (20.8%) had CKD but not diabetes at baseline, 873 (4.4%) had diabetes but not CKD, and 571 (2.9%) had both conditions. The primary composite outcome was time to myocardial infarction, coronary death, or percutaneous/surgical coronary revascularization. Median follow-up was 64 mo. After adjustment for trial and random treatment assignment, the incidence of the primary outcome was lowest in individuals with neither CKD nor diabetes (15.2%), intermediate in individuals with only CKD (18.6%) or only diabetes (21.3%), and highest in individuals with both characteristics (27.0%). Pravastatin reduced the relative likelihood of the primary outcome to a similar extent in subgroups defined by the presence or absence of CKD and diabetes. For example, pravastatin was associated with a significant reduction in the relative risk of the primary outcome by 25% in patients with CKD and concomitant diabetes and by 24% in individuals with neither characteristic. However, the absolute reduction in the risk of the primary outcome as a result of pravastatin use was highest in patients with both CKD and diabetes (6.4%) and lowest in individuals with neither characteristic (3.5%). In conclusion, stage 2 or early stage 3 CKD and diabetes both are associated with higher cardiovascular risk, and pravastatin reduces cardiovascular event rates in people with neither, one, or both characteristics. Given the high absolute benefit of pravastatin in patient with diabetes and stage 2 or early stage 3 CKD, this population in particular should be targeted for widespread use of statins. Additional studies are needed to determine whether these benefits apply to patients with more severe CKD, and recruitment to such studies should be given high priority.
Adult↗
Neither plasma coenzyme Q10 concentration, nor its decline during pravastatin therapy, is linked to recurrent cardiovascular disease events: a prospective case-control study from the LIPID study.
Statins decrease LDL cholesterol and the risk of atherosclerotic cardiovascular disease (CVD). They also decrease coenzyme Q10 (CoQ10), an effect that may negate some of the statin benefit on CVD. We examined the relationship between plasma CoQ10 concentration and CVD in a prospective case-control study of the effect of pravastatin. Plasma samples from 250 LIPID trial patients who over 6 years suffered a recurrent CVD event (CVD death, nonfatal MI or stroke) and 250 matched controls who remained event-free for the same duration of follow-up were assayed for CoQ10 and lipids (cholesterol and cholesterylesters). Mean plasma CoQ10 concentrations were significantly lower in pravastatin-treated patients than in those assigned placebo (0.51 versus 0.60 micromol/L, P = 0.006), and there was a moderate correlation between CoQ10 and common cholesterylesters (Pearson correlation coefficients in patients randomised to placebo, range r = 0.42-0.63). Univariate conditional logistic regression did not suggest any relationship between plasma CoQ10 and the risk of future CVD events (odds ratio 1.18; 95% CI 0.74-1.87; P = 0.49). Instead, we observed a reduction in the rate of recurrent CVD events with increasing ratio of plasma cholesterylarachidonate to cholesteryllinoleate. This study confirms that pravastatin lowers plasma CoQ10 concentrations, but this does not appear to predict the risk of recurrent CVD events.
Cardiovascular Diseases↗
Direct thrombin inhibitors in acute coronary syndromes: effect in patients undergoing early percutaneous coronary intervention.
AIMS: We evaluated the effect of direct thrombin inhibitors (DTIs) in patients undergoing early percutaneous coronary intervention (PCI), using the DTI Trialists' Collaboration database of 35,970 patients from 11 randomized trials of DTIs vs. heparin. METHODS AND RESULTS: We performed a Cox proportional hazards regression analysis with PCI as a time-dependent covariate to assess the independent impact of DTIs according to the performance of early PCI. PCI was performed in 7049 patients in the first 72 h after randomization. In trials in which PCI was not planned, DTIs were associated with a 10% relative risk reduction in death or myocardial infarction at 30 days (HR=0.90, 95% CI: 0.84-0.97). This benefit was found to be greater in patients undergoing early PCI (HR=0.66, 95% CI: 0.48-0.91) than those undergoing non-early PCI (HR=0.94, 95% CI: 0.86-1.03). After adjustment for baseline characteristics and propensity to undergo PCI, the risk of death or myocardial infarction remained lower with DTI (HR=0.62, 95% CI: 0.44-0.89). CONCLUSION: After adjustment for baseline differences and propensity to undergo early PCI, DTIs appeared to be more effective than heparin in reducing death or re-infarction among patients undergoing early PCI.
Acute Disease↗
Effect of pravastatin on rate of kidney function loss in people with or at risk for coronary disease.
BACKGROUND: Limited data suggest that HMG-CoA reductase inhibitors (statins) reduce rates of kidney function loss. We performed this analysis to determine whether pravastatin reduced the rate of kidney function loss over approximately 5 years in people with or at high risk for coronary disease. METHODS AND RESULTS: This was a post hoc subgroup analysis of data from 3 randomized double-blind controlled trials comparing pravastatin 40 mg/d and placebo in subjects with a previous acute coronary syndrome or who were at high cardiovascular risk. The primary outcome was the rate of change in estimated glomerular filtration rate (GFR; in mL/min per 1.73 m2/y). The Modified Diet and Renal Disease Study (MDRD) and Cockcroft-Gault equations were used to estimate GFR. We studied 18,569 participants, 3402 (18.3%) of whom had moderate chronic kidney disease as defined by an estimated GFR of 30 to 59.9 mL/min per 1.73 m2 body surface area. In subjects with moderate chronic kidney disease at baseline, pravastatin reduced the adjusted rate of kidney function loss by approximately 34%, although the absolute reduction in the rate of loss was small (0.22 mL/min per 1.73 m2/y by MDRD-GFR; 95% CI, 0.07 to 0.37). Pravastatin did not reduce the frequency of > or =25% decreases in kidney function in this group when MDRD-GFR was used to estimate GFR (relative risk [RR], 0.84; 95% CI, 0.66 to 1.06). When all 18,569 subjects were considered, pravastatin reduced the adjusted rate of kidney function loss by 8% (0.08 mL/min per 1.73 m2/y by MDRD-GFR; 95% CI, 0.01 to 0.15) and the risk of acute renal failure (RR, 0.60; 95% CI, 0.41 to 0.86) but did not significantly reduce the frequency of a > or =25% decline in kidney function by MDRD-GFR (RR, 0.94; 95% CI, 0.88 to 1.01). CONCLUSIONS: Pravastatin modestly reduced the rate of kidney function loss in people with or at risk for cardiovascular disease. However, the primary indication for the use of statins in people with or at risk for coronary events remains the reduction in mortality that results from their use.
Aged↗
Outcomes of patients with acute coronary syndromes and prior percutaneous coronary intervention: a pooled analysis of three randomized clinical trials.
AIMS: We sought to characterize the outcomes of patients with a prior percutaneous coronary intervention (PCI) who presented with a non-ST-segment elevation acute coronary syndrome (ACS). METHODS AND RESULTS: We analysed the 30 and 180 day outcomes of 3012 patients with prior PCI and 21 154 patients without prior PCI enrolled in three randomized ACS trials (GUSTO IIb, PURSUIT, and PARAGON-B). The median (25th, 75th percentile) interval between the prior PCI and randomization was 647 (123, 1585) days. Patients with prior PCI had significantly more adverse baseline clinical characteristics, left ventricular dysfunction, and multi-vessel coronary artery disease. After adjusting for baseline characteristics and treatment, we found that patients with prior PCI had a significantly lower mortality rate at 30 days [hazard ratio (HR), 0.60; 95% confidence interval (CI), 0.45-0.80; P=0.0006] and 180 days (HR, 0.81; 95% CI, 0.66-0.98; P=0.029). However, no difference was observed in the composite of death or myocardial infarction (MI) at 30 days (HR, 0.95; 95% CI, 0.83-1.08; P=0.42) or 180 days (HR, 1.01; 95% CI, 0.90-1.13; P=0.90). Patients with prior PCI had a higher rate of MI at 180 days (13.3 vs. 12.0%; P=0.045). Prior-PCI patients had lower incidences of in-hospital cardiogenic shock, congestive heart failure (CHF), and atrial fibrillation. CONCLUSION: Patients with prior PCI who present with non-ST-segment elevation ACS have a lower mortality rate than those without prior PCI.
Aged↗
Effect of pravastatin on cardiovascular events in people with chronic kidney disease.
BACKGROUND: Limited data describe the cardiovascular benefit of HMG-CoA reductase inhibitors (statins) in people with moderate chronic kidney disease (CKD). The objective of this analysis was to determine whether pravastatin reduced the incidence of cardiovascular events in people with or at high risk for coronary disease and with concomitant moderate CKD. METHODS AND RESULTS: We analyzed data from the Pravastatin Pooling Project (PPP), a subject-level database combining results from 3 randomized trials of pravastatin (40 mg daily) versus placebo. Of 19 700 subjects, 4491 (22.8%) had moderate CKD, defined by an estimated glomerular filtration rate of 30 to 59.99 mL/min per 1.73 m2 body surface area. The primary outcome was time to myocardial infarction, coronary death, or percutaneous/surgical coronary revascularization. Moderate CKD was independently associated with an increased risk of the primary outcome (adjusted HR 1.26, 95% CI 1.07 to 1.49) compared with those with normal renal function. Among the 4491 subjects with moderate CKD, pravastatin significantly reduced the incidence of the primary outcome (HR 0.77, 95% CI 0.68 to 0.86), similar to the effect of pravastatin on the primary outcome in subjects with normal kidney function (HR 0.78, 95% CI 0.65 to 0.94). Pravastatin also appeared to reduce the total mortality rate in those with moderate CKD (adjusted HR 0.86, 95% CI 0.74 to 1.00, P=0.045). CONCLUSIONS: Pravastatin reduces cardiovascular event rates in people with or at risk for coronary disease and concomitant moderate CKD, many of whom have serum creatinine levels within the normal range. Given the high risk associated with CKD, the absolute benefit that resulted from use of pravastatin was greater than in those with normal renal function.
Adult↗
Risk factors for intracranial hemorrhage and nonhemorrhagic stroke after fibrinolytic therapy (from the GUSTO-i trial).
Of 592 patients in the Global Utilization of Streptokinase and tPA for Occluded Arteries-I trial who had a stroke during initial hospitalization, the risk for intracranial hemorrhage was significantly greater in those with recent facial or head trauma (odds ratio 13.0, 95% confidence interval 3.4 to 85.5); dementia was additionally associated with an increased risk for intracranial hemorrhage (odds ratio 3.4, 95% confidence interval 1.2 to 10.2). Because facial or head trauma may greatly influence treatment decisions, this risk factor should be incorporated into models designed to estimate the risks and benefits of fibrinolytic therapy.
Aged↗
Effects of pravastatin on coronary events in 2073 patients with low levels of both low-density lipoprotein cholesterol and high-density lipoprotein cholesterol: results from the LIPID study.
AIMS: Fibrates or nicotinic acid are usually recommended for secondary prevention of coronary heart disease in patients with low plasma levels of both low-density lipoprotein cholesterol (LDL-C) < or =140 mg/dL (< or =3.6 mmol/L) and high-density lipoprotein cholesterol (HDL-C) < or =40 mg/dL (< or =1.03 mmol/L). The LIPID trial, a randomised, placebo-controlled trial in 9014 patients at 87 centres in Australia and New Zealand, provided an opportunity to investigate the effects of an HMG-CoA reductase inhibitor in patients with low LDL-C and low HDL-C. METHODS AND RESULTS: Participants in this post hoc substudy were 2073 patients aged 31-75 years with baseline LDL-C < or =140 mg/dL (< or =3.6 mmol/L), HDL-C < or =40 mg/dL (< or =1.03 mmol/L), and triglyceride < or =300 mg/dL (< or =3.4 mmol/L). The relative risk reduction with pravastatin treatment was 27% for major coronary events (95% CI 8-42%), 27% for coronary heart disease mortality (95% CI 0-47%), 21% for all-cause mortality (95% CI 0-38%), and 51% for stroke (95% CI 24-69%). The number needed to treat to prevent a major coronary event over 6 years was 22. CONCLUSIONS: Treatment with pravastatin in patients with both low LDL-C and low HDL-C significantly reduced major coronary events, stroke, and all-cause mortality. The level of HDL-C is crucial to the risk of recurrent CHD events and, consequently, the benefit of lowering LDL-C.
Adult↗
A systematic review of physicians' survival predictions in terminally ill cancer patients.
OBJECTIVE: To systematically review the accuracy of physicians' clinical predictions of survival in terminally ill cancer patients. DATA SOURCES: Cochrane Library, Medline (1996-2000), Embase, Current Contents, and Cancerlit databases as well as hand searching. STUDY SELECTION: Studies were included if a physician's temporal clinical prediction of survival (CPS) and the actual survival (AS) for terminally ill cancer patients were available for statistical analysis. Study quality was assessed by using a critical appraisal tool produced by the local health authority. DATA SYNTHESIS: Raw data were pooled and analysed with regression and other multivariate techniques. RESULTS: 17 published studies were identified; 12 met the inclusion criteria, and 8 were evaluable, providing 1563 individual prediction-survival dyads. CPS was generally overoptimistic (median CPS 42 days, median AS 29 days); it was correct to within one week in 25% of cases and overestimated survival by at least four weeks in 27%. The longer the CPS the greater the variability in AS. Although agreement between CPS and AS was poor (weighted kappa 0.36), the two were highly significantly associated after log transformation (Spearman rank correlation 0.60, P < 0.001). Consideration of performance status, symptoms, and use of steroids improved the accuracy of the CPS, although the additional value was small. Heterogeneity of the studies' results precluded a comprehensive meta-analysis. CONCLUSIONS: Although clinicians consistently overestimate survival, their predictions are highly correlated with actual survival; the predictions have discriminatory ability even if they are miscalibrated. Clinicians caring for patients with terminal cancer need to be aware of their tendency to overestimate survival, as it may affect patients' prospects for achieving a good death. Accurate prognostication models incorporating clinical prediction of survival are needed.
Analysis of Variance↗