The international PROGRESS registry of patients with severe sepsis: drotrecogin alfa (activated) use and patient outcomes.

INTRODUCTION: Since the launch of drotrecogin alfa activated (DrotAA), institutions and individual countries have published data on its use in clinical practice, based on audit or registry data. These studies were limited in size and geographic locale and included patients with greater disease severity and higher mortality than those in clinical trials. The purpose of this study was to compare baseline characteristics and clinical outcomes (using appropriate statistical adjustments) of patients treated or not treated with DrotAA from the international PROGRESS (Promoting Global Research Excellence in Severe Sepsis) cohort study of severe sepsis. METHODS: PROGRESS was a global, non-interventional, multi-center, prospective, observational study of patients having a diagnosis of severe sepsis treated in intensive care units at a participating institution. All treatment modalities were as per standard of care at the participating institutions. Baseline characteristics and hospital mortality were analyzed and regression techniques used to develop propensity and outcome models adjusted for baseline imbalances between groups. RESULTS: Overall, 14,543 patients from 37 countries were enrolled and 12,492 had complete data for analysis. Germany was the highest enrolling country (1,810; 14.5%) and the US had the most DrotAA patients (206, 23.3%); 882 (7%) overall received DrotAA therapy. DrotAA-treated patients were younger (median age 58 vs. 61 years), had greater organ dysfunction (cardiovascular: 90% vs. 74%; respiratory: 90% vs. 81%; renal: 60% vs. 45%; metabolic: 63% versus 42%; 3 or more organ dysfunctions: 84% vs. 67%) and had a higher median APACHE II score (26 vs. 23, all with P < 0.001). Although in-hospital mortality was similar for DrotAA and non-DrotAA-treated patients (49.6% vs. 49.7%, respectively), after adjusting for imbalances, patients receiving DrotAA had a 28% (0.60 to 0.86, 95% Confidence Intervals) reduction in the odds of death and a relative risk reduction of 17% (P = 0.0003). CONCLUSIONS: In the PROGRESS registry, DrotAA-treated patients were younger, more severely ill, and had fewer co-morbidities than patients not treated with DrotAA. After adjustment for group differences, a significant reduction in the odds of death was observed for patients that received DrotAA compared with those that did not.

Drotrecogin alfa (activated) in children with severe sepsis: a multicentre phase III randomised controlled trial.

BACKGROUND: Drotrecogin alfa (activated) (DrotAA) is used for the treatment of adults with severe sepsis who have a high risk of dying. A phase 1b open-label study has indicated that the pharmacokinetics and pharmacodynamics of DrotAA are similar in children and adults. We initiated the RESOLVE (REsearching severe Sepsis and Organ dysfunction in children: a gLobal perspectiVE) trial to investigate the efficacy and safety of the drug in children. METHODS: Children aged between 38 weeks' corrected gestational age and 17 years with sepsis-induced cardiovascular and respiratory failure were randomly assigned to receive placebo or DrotAA (24 microg/kg/h) for 96 h. We used a prospectively defined, novel primary endpoint of Composite Time to Complete Organ Failure Resolution (CTCOFR) score. Secondary endpoints were 28-day mortality, major amputations, and safety. Analysis was by intention-to-treat. This trial is registered with clinicaltrials.gov, number NCT00049764. FINDINGS: 477 patients were enrolled; 237 received placebo, and 240 DrotAA. Our results showed no significant difference between groups in CTCOFR score (p=0.72) or in 28-day mortality (placebo 17.5%; DrotAA, 17.2%; p=0.93). Although there was no difference in overall serious bleeding events during the 28-day study period (placebo 6.8%; DrotAA 6.7%; p=0.97), there were numerically more instances of CNS bleeding in the DrotAA group (11 [4.6%], vs 5 [2.1%] in placebo, p=0.13), particularly in children younger than 60 days. For CTCOFR score days 1-14, correlation coefficient was -0.016 (95% CI -0.106 to 0.74); relative risk for 28-day mortality was 1.06 (95% CI 0.66 to 1.46) for DrotAA compared with placebo. INTERPRETATION: Although we did not record any efficacy of DrotAA in children with severe sepsis, serious bleeding events were similar between groups and the overall safety profile acceptable, except in children younger than 60 days. However, we gained important insights into clinical and laboratory characteristics of childhood severe sepsis, and have identified issues that need to be addressed in future trials in critically ill children.

Protein C concentrations in severe sepsis: an early directional change in plasma levels predicts outcome.

INTRODUCTION: Protein C, because of its central role in hemostasis, plays an integral role in the host response to infection. Protein C depletion, resulting from increased consumption, degradation, and/or decreased synthesis, is characteristic of sepsis and has been shown to predict morbidity and mortality. The objective of this study was to determine whether early directional changes in protein C levels correlate with outcome. METHODS: Patients in the Recombinant Human Activated Protein C Worldwide Evaluation in Severe Sepsis (PROWESS) clinical trial were assessed and categorized by baseline protein C (n = 1574). Deficiency was categorized as: severe deficiency, protein C levels < or = 40% of normal protein C activity (n = 615, 39% of patients); deficient, protein C levels 41-80% of normal protein C activity (n = 764, 48.5% of patients); and normal, >80% of normal protein C activity (n = 195, 12.4% of patients). Logistic regression analysis of 28-day mortality for placebo patients was used to investigate whether baseline and day 1 protein C levels were independent risk factors for mortality. The impact of treatment with drotrecogin alfa (activated) (DrotAA) was also assessed. RESULTS: Protein C levels at baseline and day 1 were independent risk factors in placebo patients. If baseline protein C levels of severely deficient placebo patients remained < or = 40% at day 1 their odds of death increased (odds ratio = 2.75, P < 0.0001), while if levels improved to >40% by day 1 their risk of death decreased (odds ratio = 0.43, P = 0.03). If baseline protein C levels of placebo patients were >40% but decreased by > or = 10% on day 1, their risk of death increased (odds ratio = 1.87, P = 0.02). DrotAA treatment improved protein C levels by day 1 compared with placebo (P = 0.008) and reduced the risk of death in severely deficient (< or = 40%) patients at baseline. Treatment also decreased the number of severely protein C deficient (= 40%) patients and decreased the number of deficient (41-80%) patients and normal (>80%) patients who had a > or = 10% decrease in protein C levels by day 1. CONCLUSION: Baseline protein C levels were an independent predictor of sepsis outcome. Day 1 changes in protein C, regardless of baseline levels, were also predictive of outcome. The association of DrotAA treatment, increased protein C levels, and improved survival may partially explain the mechanism of action.

Use of an integrated clinical trial database to evaluate the effect of timing of drotrecogin alfa (activated) treatment in severe sepsis.

INTRODUCTION: Several studies have indicated that early identification and treatment of patients with severe sepsis using standard supportive care improves outcomes. Earlier treatment with drotrecogin alfa (activated) (DrotAA) may also improve outcomes in severe sepsis. Using a recently constructed integrated severe sepsis database, our objectives in this study were to describe the influence of baseline clinical characteristics on timing of DrotAA treatment in patients with severe sepsis, to evaluate the efficacy of DrotAA with respect to timing of administration, and to examine the association between early intervention with DrotAA and patient outcomes, using adjustments for imbalances. METHODS: The database comprises data from 4,459 patients with severe sepsis (DrotAA, n = 3,228; placebo, n = 1,231) included in five clinical trials conducted in tertiary care institutions in 28 countries. Placebo data came only from randomized trials, whereas data for the DrotAA group came from randomized (PROWESS) and open-label/observational (ENHANCE) trials. RESULTS: Increased time-to-treatment with DrotAA was significantly associated with more organ dysfunction, greater need of mechanical ventilation, vasopressor use, or recent surgery. Earlier treatment was associated with higher baseline Acute Physiology and Chronic Health Evaluation (APACHE II) scores. Adjusted and unadjusted survival analyses suggested that compared with placebo, DrotAA treatment provided a potential survival benefit, regardless of time to treatment. Survival curves of DrotAA patients treated early compared with those treated late began to separate at 14 days. By 28 days, patients treated earlier had higher survival than those treated later (76.4% versus 73.5%, p = 0.03). Sepsis-induced multiorgan dysfunction was the most common cause of death followed by refractory shock and respiratory failure. Modeling of the treatment effect, as a function of time to treatment, suggested increased benefit with earlier treatment. CONCLUSION: Using an integrated database of five severe sepsis trials and appropriate statistical adjustments to reduce sources of potential bias, earlier treatment with DrotAA seemed to be associated with a lower risk-adjusted mortality than later treatment. These data suggest that earlier treatment with DrotAA may provide most benefit for appropriate patients.

Effects of drotrecogin alfa (activated) in human endotoxemia.

In a phase III clinical trial, drotrecogin alfa (activated) was shown to improve survival and promote faster improvement of cardiovascular and respiratory dysfunction in patients with severe sepsis. To further examine mechanisms involved in the action of this drug, a healthy human endotoxin model was used. Healthy volunteers (eight per group) received drotrecogin alfa (activated) or placebo intravenously for 8 h in a randomized, double-blind, controlled manner. After 2 h of study drug infusion, endotoxin (2 ng/kg) was infused and measurement of physiologic responses and biomarkers continued for 24 h. Consistent with results from severe sepsis clinical trials, drotrecogin alfa (activated) improved mean arterial pressure during the period of infusion after endotoxin exposure. In contrast to severe sepsis clinical trials using drotrecogin alfa (activated) but similar to another human endotoxin study, no significant antithrombotic, profibrinolytic, or anti-inflammatory effects were observed. These results suggest a novel role for drotrecogin alfa (activated) in the human endotoxin model.

Tadalafil monotherapy and as add-on to background bosentan in patients with pulmonary arterial hypertension.

BACKGROUND: Tadalafil 40 mg orally once daily, was shown to be well-tolerated and efficacious for pulmonary arterial hypertension in a 16-week, double-blind, placebo (PBO)-controlled trial. Inclusion criteria included the option for background bosentan. Analyses of tadalafil in treatment-naive patients and as add-on to bosentan were pre-specified. Objectives were to provide safety and efficacy data for both groups. METHODS: Groups analyzed included: treatment-naive + PBO; treatment-naive + tadalafil; background bosentan + PBO; and background bosentan + tadalafil. Patients randomized to tadalafil or PBO (N = 405) were analyzed by bosentan use (yes = 216, no = 189). Treatment differences in 6-minute walk distance (6MWD, PBO-adjusted), functional class (FC), clinical worsening (CW) and adverse events were assessed. Hazard ratios (HRs) with 95% confidence intervals (CIs) are presented for FC and CW. RESULTS: At Week 16, PBO-adjusted 6MWD increases were 44 m (CI: 20 to 69 m; n = 37) for tadalafil 40 mg in treatment-naive patients and 23 m (CI: -2 to 48 m; n = 42) for tadalafil 40 mg add-on to bosentan. The 6MWD for treatment-naive and background bosentan PBO patients decreased by 3 m and increased by 19 m, respectively, at Week 16 compared with baseline. Two (5%) treatment-naive patients had CW with tadalafil 40 mg vs 8 (22%) with PBO (HR = 3.3, CI: 1.1 to 10.0). Two (5%) background bosentan patients had CW with tadalafil 40 mg add-on vs 5 (11%) for PBO add-on (HR = 1.9, CI: 0.4 to 10.2). Adverse events for tadalafil monotherapy and as add-on were similar. CONCLUSION: Tadalafil 40 mg was well-tolerated and provided clinical benefit in patients as monotherapy. It was also well-tolerated when added to background bosentan, but data are insufficient to conclude additional benefit.

Efficacy and safety of tadalafil once daily in the treatment of men with lower urinary tract symptoms suggestive of benign prostatic hyperplasia: results of an international randomized, double-blind, placebo-controlled trial.

BACKGROUND: Tadalafil is being investigated for the treatment of lower urinary tract symptoms (LUTS) suggestive of benign prostatic hyperplasia (BPH-LUTS). OBJECTIVE: To assess efficacy, including onset, and safety of tadalafil on BPH-LUTS and the subject's and clinician's perception of changes in urinary symptoms. DESIGN, SETTING, AND PARTICIPANTS: This randomized, double-blind, placebo-controlled, 12-week trial enrolled men ≥45 yr of age with BPH-LUTS for >6 mo, International Prostate Symptom Score (IPSS) ≥13, and maximum urine flow rate (Q(max)) ≥4 to ≤15 ml/s. INTERVENTION: Tadalafil 5mg (n=161) or placebo (n=164), once daily. MEASUREMENTS: Analysis of covariance (ANCOVA) modeling evaluated change from baseline in continuous efficacy variables. Categoric efficacy variables were analyzed with the Cochran-Mantel-Haenszel test, and between-group differences in treatment-emergent adverse events (TEAEs) were assessed using the Fisher exact test. RESULTS AND LIMITATION: Tadalafil significantly improved IPSS results, from baseline to endpoint, compared to placebo (-5.6 vs -3.6; p=0.004). Reduction in IPSS results was apparent after 1 wk and significant after 4 wk (tadalafil -5.3 vs placebo -3.5; p=0.003). The BPH Impact Index (BII) was not assessed at week 1; however, BII improvement was apparent at 4 wk (tadalafil -1.8 vs placebo -1.2; p=0.029) and continued at 12 wk (tadalafil -1.8 vs placebo -1.3; p=0.057). Tadalafil significantly improved the International Index of Erectile Function-Erectile Function score in sexually active men with erectile dysfunction (ED; 6.7 vs 2.0; p<0.001) at 12 wk (not assessed at week 1). Few subjects reported one TEAE or more (p=0.44). For tadalafil, the most common TEAEs were headache (3.7%) and back pain (3.1%). Tadalafil did not significantly improve Q(max) or reduce postvoid residual volume. CONCLUSIONS: Tadalafil 5mg once daily for 12 wk resulted in a clinically meaningful reduction in total IPSS results as early as 1 wk and achieved statistical significance at 4 wk in men with BPH-LUTS. The adverse event profile was consistent with that previously reported in men with ED. TRIAL REGISTRATION: This clinical trial is registered on the clinicaltrials.gov website (http://www.clinicaltrials.gov). The registration number is NCT00827242.

Prophylactic heparin in patients with severe sepsis treated with drotrecogin alfa (activated).

RATIONALE: Patients with severe sepsis frequently receive prophylactic heparin during drotrecogin alfa (activated) (DrotAA) treatment due to risk of venous thromboembolic events (VTEs). Biological plausibility exists for heparin to reduce DrotAA efficacy and/or increase bleeding. OBJECTIVES: Primary: demonstrate in adult patients with severe sepsis receiving DrotAA treatment that 28-day mortality was equivalent for patients treated with concomitant prophylactic heparin compared with placebo; secondary: safety and VTE incidence. METHODS: International, randomized, double-blind, phase 4, equivalence-design trial (n = 1994). Patients were eligible if indicated for and receiving DrotAA treatment under the country's approved label. Study drug (low molecular weight/unfractionated heparin) or placebo (saline) was administered every 12 hours during DrotAA infusion (24 ug/kg/hr for 96 hr). In patients on baseline heparin and randomized to placebo, heparin was stopped. MEASUREMENTS AND MAIN RESULTS: Twenty-eight-day mortality was not equivalent between treatment groups. Heparin mortality was numerically lower (28.3 vs. 31.9%; p = 0.08). In the prospectively defined subgroup of patients exposed to heparin at baseline, patients receiving placebo experienced higher mortality (35.6 vs. 26.9%; p = 0.005). For safety, significant differences were observed during Days 0-6 for any bleeding event (placebo, n = 78; heparin, n = 105; p = 0.049) and ischemic stroke during Days 0-6 (placebo, n = 12; heparin, n = 3; p = 0.02) and Days 0-28 (placebo, n = 17; heparin, n = 5; p = 0.009). The VTE rate was low, with no statistical difference between groups (0-6 d, p = 0.60; 0-28 d, p = 0.26). CONCLUSIONS: Compared with placebo, concomitant prophylactic heparin was not equivalent, did not increase 28-day mortality, and had an acceptable safety profile in patients with severe sepsis receiving DrotAA. Heparin discontinuation should be carefully weighed in patients considered for DrotAA treatment. XPRESS clinical trial registered with www.clinicaltrials.gov (NCT 00049777). The study ID numbers are 6743; F1K-MC-EVBR.

Drotrecogin alfa (activated) treatment in severe sepsis from the global open-label trial ENHANCE: further evidence for survival and safety and implications for early treatment.

OBJECTIVE: To provide further evidence for the efficacy and safety of drotrecogin alfa (activated) treatment in severe sepsis. DESIGN: Single-arm, open-label, trial of drotrecogin alfa (activated) treatment in severe sepsis patients. Enrollment began in March 2001 and day-28 follow-up completed in January 2003. SETTING: ENHANCE took place in 25 countries at 361 sites. PATIENTS: Patients with known or suspected infection, three or four systemic inflammatory response syndrome criteria, and one or more sepsis-induced organ dysfunctions. Of 2,434 adults entered, 2,378 received drotrecogin alfa (activated), and of these, 2,375 completed the protocol. INTERVENTIONS: Drotrecogin alfa (activated) was infused at a dose of 24 mug/kg/hr for 96 hrs. MEASUREMENTS AND MAIN RESULTS: The 28-day all-cause mortality approximated that observed in PROWESS (25.3% vs. 24.7%). Although patients in ENHANCE had increased serious bleeding rates compared with patients in the drotrecogin alfa (activated) arm of PROWESS (during infusion, 3.6% vs. 2.4%; postinfusion, 3.2% vs. 1.2%; 28-day, 6.5% vs. 3.5%), increased postinfusion bleeding suggested a higher background bleeding rate. Intracranial hemorrhage was more common in ENHANCE than PROWESS (during infusion, 0.6% vs. 0.2%; 28-day, 1.5% vs. 0.2%). The incidence of fatal intracranial hemorrhage was the same during infusion (0.2%) and higher at 28 days (0.5% vs. 0.2%). ENHANCE patients treated within 0-24 hrs from their first sepsis-induced organ dysfunction had lower observed mortality rate than those treated after 24 hrs (22.9% vs. 27.4%, p = .01). CONCLUSIONS: ENHANCE provides supportive evidence for the favorable benefit/risk ratio observed in PROWESS and suggests that more effective use of drotrecogin alfa (activated) might be obtained by initiating therapy earlier.

Clusterin protects renal tubular epithelial cells from gentamicin-mediated cytotoxicity.

Clusterin is a heterodimeric secreted glycoprotein that is upregulated after acute renal injury. In aminoglycoside nephrotoxicity, clusterin is induced in the tubular epithelium and increased levels are found in the urine. In this study, we developed an in vitro model of gentamicin-induced cytotoxicity in renal proximal tubule cells and tested whether clusterin protected these cells from injury. LLC-PK(1) cells were incubated with varying concentrations of gentamicin in serum-free media, and cytotoxicity was quantified by lactate dehydrogenase release and confirmed by vital dye exclusion. A dose-dependent increase in cytotoxicity occurred with gentamicin concentrations up to 27 mg/ml. Clusterin decreased cytotoxicity in a dose- and time-dependent manner at 6, 12, and 24 h, whereas albumin, used as a control protein, had no effect. In contrast to the aminoglycoside model, when cells were injured by depletion of ATP, clusterin had only a minimally protective effect. LLC-PK(1) cells did not express megalin, a receptor that can mediate the uptake of both clusterin and aminoglycosides into proximal tubule cells. Uptake of gentamicin into LLC-PK(1) cells was observed despite the absence of megalin. In conclusion, clusterin specifically protects against gentamicin-induced renal tubular cell injury by a megalin-independent mechanism.

Gentamicin inhibits renal protein and phospholipid metabolism in rats: implications involving intracellular trafficking.

Studies were undertaken to characterize the mechanism of aminoglycoside-induced nephrotoxicity. Early time points in gentamicin treatment (1 to 3 d) were used to investigate the development of toxic events without the complication of gross morphologic cellular alterations. Enzyme activities of cortical homogenates and brush border membrane (BBM) preparations documented little effect on specific activities or the ability to isolate representative membrane fractions. In vivo protein synthesis experiments demonstrated that gentamicin reduced cellular protein synthesis after 2 d of treatment. This inhibition increased to 50% on the third day. Total cellular proteins synthesis was inhibited to the same extent as BBM protein synthesis. However, gentamicin had different effects on homogenate versus BBM phospholipids. The total phospholipid contents in cortical homogenates and BBM from treated animals were increased, compared with control animals. A significant decrease in phospholipid synthesis was observed only in homogenates from treated animals. When effects on individual phospholipids were investigated, only an increase in phosphatidylinositol levels was observed in cortical homogenates from treated rats. However, gentamicin treatment was demonstrated to increase the levels of phosphatidylinositol and phosphatidylcholine, while decreasing the level of sphingomyelin (SPH), in BBM. Incorporation of (32)P into SPH, phosphatidylserine, and phosphatidylethanolamine was inhibited in cortical homogenates from gentamicin-treated animals; among BBM phospholipids, however, a significant decrease was observed only for SPH synthesis. It was concluded that inhibition of phospholipid degradation was quantitatively the major contributor to the effects of gentamicin on phospholipid metabolism. Confocal microscopic studies, using tracer amounts of fluorescently labeled gentamicin, revealed gentamicin in large, mostly basal structures. Correlative electron microscopic studies, using photo-oxidation techniques, demonstrated that these structures consisted of lysosomal, Golgi complex, and mitochondrial structures. These observations suggest retrograde trafficking of gentamicin and indicate a general mechanism of gentamicin-induced nephrotoxicity.

Urinary megalin deficiency implicates abnormal tubular endocytic function in Fanconi syndrome.

Normal reabsorption of glomerular filtrate proteins probably requires recycling of the endocytic receptors megalin (gp330) and cubilin. Both receptors are located on the luminal surface of the renal proximal tubule epithelium. Whether abnormal amounts of receptor are present in the urine of patients with Dent's disease, Lowe's syndrome, or autosomal dominant idiopathic Fanconi syndrome was explored. They are all forms of the renal Fanconi syndrome and are associated with tubular proteinuria. Urine samples of equal creatinine contents were dialyzed, lyophilized, and subjected to electrophoresis on nonreducing sodium dodecyl sulfate-5% polyacrylamide gels. Proteins were blotted and probed with anti-megalin IgG, anti-cubilin IgG, or receptor-associated protein. Megalin and cubilin levels detected by immunochemiluminescence were measured as integrated pixels and expressed as percentages of the normal mean values. A striking deficiency of urinary megalin, compared with normal individuals (n = 42), was observed for eight of nine families with Dent's disease (n = 10) and for the two families with Lowe's syndrome (n = 3). The family with autosomal dominant idiopathic Fanconi syndrome (n = 2) exhibited megalin levels within the normal range. The measured levels of cubilin were normal for all patients. These results are consistent with defective recycling of megalin to the apical cell surface of the proximal tubules and thus decreased loss into urine in Dent's disease and Lowe's syndrome. This defect would interfere with the normal endocytic function of megalin, result in losses of potential ligands into the urine, and produce tubular proteinuria.