Prolonged remission from hepatic encephalopathy with rifaximin: results of a placebo crossover analysis.

BACKGROUND: Rifaximin therapy reduced risk of hepatic encephalopathy (HE) recurrence and HE-related hospitalisations during a 6-month, randomised, placebo-controlled trial (RCT) and a 24-month open-label maintenance (OLM) study. However, the impact of crossover from placebo to rifaximin therapy is unclear. AIM: To study the impact of crossing over from placebo to rifaximin treatment on breakthrough HE and hospitalisation rates using a within-subjects design. METHODS: Adults with cirrhosis and history of overt HE episodes, currently in HE remission, received placebo during the RCT and crossed over to rifaximin 550 mg twice daily during the OLM study. Rate of breakthrough overt HE episodes, hospitalisations and incidence and rate of adverse events (AEs) were analysed during RCT and first 6 months of OLM. RESULTS: Of 82 patients randomised to placebo in the RCT who crossed over to the OLM study, 39 experienced an HE episode during the RCT compared with 14 during the OLM study (P < 0.0001). Significantly lower rates of HE events were observed with rifaximin treatment compared with placebo treatment (P < 0.0001). Rates of HE-related hospitalisation were numerically lower during rifaximin treatment compared with placebo treatment, although not significant. Rates of most common AEs, serious AEs and infection-related AEs were similar between the two treatments. CONCLUSIONS: This analysis confirms the repeatability of results from the RCT on safety and efficacy of rifaximin 550 mg twice daily in reducing the risk of hepatic encephalopathy recurrence, and suggests these findings are translatable outside of a rigorous, controlled trial setting.

A retrospective analysis: the development of patient reported outcome measures for the assessment of Crohn's disease activity.

BACKGROUND: The Crohn's Disease Activity Index (CDAI) is a measure of disease activity based on symptoms, signs and a laboratory test. The US Food and Drug Administration has indicated that patient reported outcomes (PROs) should be the primary outcome in randomised controlled trials for Crohn's disease (CD). AIM: As no validated PRO exists for CD, to investigate whether CDAI diary card items could be modified for this purpose. METHODS: Data from a trial of rifaximin-extended intestinal release were used to identify cut-points for stool frequency, pain and general well-being using receiver operating characteristic curves with CDAI <150 as criterion. The operating properties of 2- and 3-item PRO were evaluated using data from a trial of methotrexate in CD. Regression analysis determined PRO2 and PRO3 scores that correspond to CDAI-defined thresholds of 150, 220 and 450 and changes of 50, 70 and 100 points. RESULTS: Optimum cut-points for CDAI remission were mean daily stool frequency ≤1.5, abdominal pain ≤1, and general well-being score of ≤1 (areas under the ROC curve 0.79, 0.91 and 0.89, respectively). The effect estimates were similar using 2- and 3-item PROs or CDAI. PRO2 and PRO3 values corresponding to CDAI scores of 150, 220 and 450 points were 8, 14, 34 and 13, 22, 53. The corresponding values for CDAI changes of 50, 70 and 100, were 2, 5, 8 and 5, 9, 14. Responsiveness to change was similar for both PROs. CONCLUSION: Patient reported outcomes derived from CDAI diary items may be appropriate for use in clinical trials for CD.

Safety and tolerability of rifaximin for the treatment of irritable bowel syndrome without constipation: a pooled analysis of randomised, double-blind, placebo-controlled trials.

BACKGROUND: The efficacy of rifaximin, a nonsystemic, gut-targeted antibiotic for reducing non-constipation-predominant irritable bowel syndrome (non-C IBS) symptoms, has been demonstrated in one phase 2b and two phase 3 randomised, double-blind, placebo-controlled trials, but detailed data about rifaximin safety and tolerability during treatment and subsequent follow-up periods are lacking. AIM: To assess and determine the frequency of rifaximin and placebo adverse events (AEs) in phase 2b and phase 3 non-C IBS trials. METHODS: A post hoc pooled safety analysis of the phase 2b (rifaximin 275, 550, and 1100 mg twice daily for 2 weeks; 550 mg twice daily for 4 weeks) and phase 3 (rifaximin 550 mg three times daily for 2 weeks) studies was performed. Data on treatment and post-treatment AEs were collected. Patients were followed up for 12 weeks and 10 weeks post-treatment in the phase 2b and phase 3 trials, respectively. RESULTS: Patients receiving rifaximin (n = 1103) and placebo (n = 829) had a similar incidence of drug-related AEs (12.1% vs. 10.7%), serious AEs (1.5% vs. 2.2%), drug-related AEs resulting in study discontinuation (0.8% vs. 0.8%), gastrointestinal-associated AEs (12.2% vs. 12.2%) and infection-associated AEs (8.5% vs. 9.5%). There were no cases of Clostridium difficile colitis or deaths. CONCLUSIONS: The safety and tolerability profile of rifaximin during treatment and post-treatment was comparable to placebo. Future research should define the safety and tolerability profile, including risk of C. difficile colitis and microbial antibiotic resistance, with repeated courses of rifaximin in patients with non-constipation-predominant irritable bowel syndrome (ClinicalTrials.gov: NCT00269412, NCT00731679, and NCT00724126).

Mesalazine granules 1.5 g once-daily maintain remission in patients with ulcerative colitis who switch from other 5-ASA formulations: a pooled analysis from two randomised controlled trials.

BACKGROUND: Mesalazine (mesalamine) granules (MG) were shown to be effective for the maintenance of remission of ulcerative colitis (UC) in two double-blind placebo-controlled trials. AIM: To evaluate the efficacy of once-daily MG for maintenance of remission in patients with UC who switched from other 5-aminosalicylic acid (5-ASA) formulations. METHODS: Data from two independent multicenter, randomised, double-blind, placebo-controlled, 6-month trials evaluating patients with UC in remission were combined for analysis of a subpopulation of patients who switched from other 5-ASA formulations to MG 1.5 g or placebo upon randomisation. The primary endpoint was the percentage of patients who remained relapse-free at Month 6 or end of treatment. Relapse was defined as a Sutherland Disease Activity Index (SDAI) rectal bleeding score ≥1 and mucosal appearance score ≥2, a UC flare or medication used to treat a UC flare. RESULTS: Of the 487 patients who received 5-ASA maintenance therapy at enrolment, 322 were in the MG group and 165 were in the placebo group. The percentage of patients who remained relapse-free (based on Sutherland Disease Activity Index scores) after 6 months was significantly higher with MG than placebo (78.3% vs. 58.8%, P < 0.001). Rectal bleeding, stool frequency and the physician's rating of disease activity remained unchanged after 6 months in a higher percentage of patients using MG compared with those on placebo (P < 0.004 for each endpoint). CONCLUSION: Mesalazine granules 1.5 g once-daily is effective for maintenance of remission in UC patients who switch from other 5-ASA formulations. ClinicalTrials.gov identifiers NCT00744016, NCT00767728.

Randomised clinical trial: rifaximin improves health-related quality of life in cirrhotic patients with hepatic encephalopathy - a double-blind placebo-controlled study.

BACKGROUND: Hepatic encephalopathy (HE) is a brain disorder that often results from cirrhosis due to viral hepatitis, metabolic and alcohol-related liver disease, and is characterised by cognitive, psychiatric and motor impairments. Recurrent bouts of overt HE negatively impact daily functioning and quality of life. AIM: To evaluate the effect of rifaximin on health-related quality of life (HRQL) in cirrhotic patients with HE. METHODS: Patients with cirrhosis in remission from HE (Conn score = 0 or 1) and a documented history of recurrent HE episodes (≥2 within 6 months of screening) were randomised to rifaximin 550 mg twice daily (N = 101) or placebo (N = 118) for 6 months. Concomitant lactulose was permitted during the study. The Chronic Liver Disease Questionnaire (CLDQ) was administered every 4 weeks, and time for occurrence of HE breakthrough was recorded. A longitudinal analysis using time-weighted averages of the CLDQ scores normalised by days on study therapy was used to evaluate the effect of treatment on HRQL, and between HE outcomes (HE recurrence, yes/no) irrespective of treatment. RESULTS: The time-weighted averages of the overall CLDQ score and each domain score were significantly higher in the rifaximin group vs. placebo (P-values ranged from 0.0087 to 0.0436); and were significantly lower in patients who experienced HE breakthrough compared to those who remained in remission (P-values were <0.0001). CONCLUSION: Rifaximin significantly improved HRQL in patients with cirrhosis and recurrent hepatic encephalopathy. A lower HRQL may predict recurrence of hepatic encephalopathy.

Clinical trial: once-daily mesalamine granules for maintenance of remission of ulcerative colitis - a 6-month placebo-controlled trial.

BACKGROUND: Ulcerative colitis (UC) is a chronic relapsing and remitting idiopathic inflammatory bowel disorder. AIM: To evaluate once-daily mesalamine (mesalazine) granules (MG) for maintenance of remission of UC. METHODS: Randomized, double-blind, placebo-controlled trial of patients (n=209 MG, n=96 placebo) with UC in remission [revised Sutherland Disease Activity Index (SDAI) rectal bleeding=0, mucosal appearance <2] who took MG 1.5 g or placebo once-daily for up to 6 months. Primary efficacy endpoint: the percentage of patients who remained relapse-free at month 6/end of treatment. Relapse was defined as SDAI rectal bleeding score ≥1 and a mucosal appearance score ≥2, a UC flare, or initiation of medication to treat a UC flare. RESULTS: The percentage of relapse-free patients at month 6/end of treatment was higher with MG than placebo (78.9% vs. 58.3%, P < 0.001) in the intent-to-treat analysis. Significant differences (P ≤ 0.025) favouring MG were observed for most secondary endpoints including improvement in rectal bleeding, physician's disease activity rating, stool frequency, the SDAI at month 6/end of treatment, patients classified as a treatment success and relapse-free duration. The incidence of adverse events was similar between groups. CONCLUSIONS: Once-daily mesalamine (mesalazine) was effective in maintaining remission of UC for 6 months.

Gliadel wafer in initial surgery for malignant glioma: long-term follow-up of a multicenter controlled trial.

OBJECTIVE: Adjuvant systemic chemotherapy increases survival of primary malignant glioma patients beyond 12-18 months. The only interstitial chemotherapy treatment approved for malignant glioma is Gliadel wafer containing carmustine (BCNU) placed in the resection cavity at surgery. Analysis of a large trial by Westphal and colleagues (n = 240) showed a 29% risk reduction (P = 0.03) in the BCNU wafer-treated group over the course of the 30-month trial. Long-term follow-up of these patients was undertaken to determine the survival benefit at 2 and 3 years. METHODS: Survival proportions for the placebo and treatment groups over the 56-month study were estimated by the Kaplan-Meier method. Multiple-regression analyses using the Cox proportional hazards model included prognostic factors of age, KPS, and tumor type. A secondary analysis was conducted for 207 GBM patients. RESULTS: Of the 59 patients available for long-term follow-up, 11 were alive at 56 months: 9 had received BCNU wafers and 2 had received placebo wafers. Median survival of patients treated with BCNU wafers was 13.8 months vs 11.6 months in placebo-treated patients (P = 0.017) with a hazard ratio of 0.73 (P = 0.018), representing a 27% significant risk reduction. This survival advantage was maintained at 1, 2, and 3 years and was statistically significant (P = 0.01) at 3 years. Two of 207 GBM patients remained alive at the end of the follow-up period, both in the BCNU wafer-treated group. CONCLUSION: Malignant glioma patients treated with BCNU wafers at the time of initial surgery in combination with radiation therapy demonstrated a survival advantage at 2 and 3 years follow-up compared with placebo.

The central nervous system effects, pharmacokinetics and safety of the NAALADase-inhibitor GPI 5693.

AIM: The aim was to assess the central nervous system (CNS) effects, pharmacokinetics and safety of GPI 5693, an inhibitor of a novel CNS-drug target, NAALADase which is being evaluated for the treatment of neuropathic pain. METHODS: This was a double-blind, placebo-controlled, exploratory study in healthy subjects receiving oral GPI 5693 single ascending doses of 100, 300, 750, 1125 mg with a placebo treatment randomly interspersed. An open-label, parallel extension examined the effects of food and sex on the pharmacokinetics of 750, 1125 and 1500 mg doses. Blood samples were collected for pharmacokinetic and biochemical/haematological safety analysis, vital signs, ECG and adverse event checks were performed regularly up to 48 h postdose. Postdose CNS effects were assessed using eye movements, adaptive tracking, electroencephalography (EEG), body sway and Visual Analogue Scales (VAS). RESULTS: CNS effects were mainly observed after the 1125 mg dose, showing a significant decrease of adaptive tracking performance, VAS alertness and VAS mood, and an increase of EEG occipital alpha and theta power. Gastro-intestinal (GI) adverse effects were frequent at higher doses. No clinically significant changes in vital signs or ECG were noted during any of the treatments. The therapeutically relevant concentration range (950-11 100 ng ml(-1)) as determined from animal experiments was already reached after the 300 mg dose. C(max) after the 300 mg and 750 mg dose was 2868 and 9266 ng ml(-1) with a t(1/2) of 2.54 and 4.78 h, respectively. Concomitant food intake (with the 750 mg and 1125 mg doses) reduced C(max) by approximately 66% and AUC by approximately 40%. With concomitant food intake, the dose-normalized C(max) also decreased significantly by -5.6 (CI: -2.6 to -8.7) ng ml(-1) mg(-1). The pharmacokinetic variability was largest after the 300 mg and 750 mg dose, resulting in a SD of approximately 50% of the C(max). CONCLUSION: NAALADase inhibition with GPI 5693 was safe and tolerable in healthy subjects. Plasma concentrations that were effective in the reversal of hyperalgesia in the chronic constrictive injury animal model of neuropathic pain were obtained at doses of 300, 750 and 1125 mg in the fasted state. Comcomitant food intake reduced C(max) and AUC. CNS effects and GI AEs increased in incidence over placebo only at the 1125 mg dose.

A comparison of cilostazol and pentoxifylline for treating intermittent claudication.

PURPOSE: We performed a randomized, double-blind, placebo-controlled, multicenter trial to evaluate the relative efficacy and safety of cilostazol and pentoxifylline. PATIENTS AND METHODS: We enrolled patients with moderate-to-severe claudication from 54 outpatient vascular clinics, including sites at Air Force, Veterans Affairs, tertiary care, and university medical centers in the United States. Of 922 consenting patients, 698 met the inclusion criteria and were randomly assigned to blinded treatment with either cilostazol (100 mg orally twice a day), pentoxifylline (400 mg orally 3 times a day), or placebo. We measured maximal walking distance with constant-speed, variable-grade treadmill testing at baseline and at 4, 8, 12, 16, 20, and 24 weeks. RESULTS: Mean maximal walking distance of cilostazol-treated patients (n = 227) was significantly greater at every postbaseline visit compared with patients who received pentoxifylline (n = 232) or placebo (n = 239). After 24 weeks of treatment, mean maximal walking distance increased by a mean of 107 m (a mean percent increase of 54% from baseline) in the cilostazol group, significantly more than the 64-m improvement (a 30% mean percent increase) with pentoxifylline (P <0.001). The improvement with pentoxifylline was similar (P = 0.82) to that in the placebo group (65 m, a 34% mean percent increase). Deaths and serious adverse event rates were similar in each group. Side effects (including headache, palpitations, and diarrhea) were more common in the cilostazol-treated patients, but withdrawal rates were similar in the cilostazol (16%) and pentoxifylline (19%) groups. CONCLUSION: Cilostazol was significantly better than pentoxifylline or placebo for increasing walking distances in patients with intermittent claudication, but was associated with a greater frequency of minor side effects. Pentoxifylline and placebo had similar effects.

A new pharmacological treatment for intermittent claudication: results of a randomized, multicenter trial.

BACKGROUND: Effective medication is limited for the relief of intermittent claudication, a common manifestation of arterial occlusive disease. Cilostazol is a potent inhibitor of platelet aggregation with vasodilation effects. OBJECTIVE: To evaluate the safety and efficacy of cilostazol for the treatment of intermittent claudication. METHODS: Thirty-seven outpatient vascular medicine clinics at regional tertiary and university hospitals in the United States participated in this multicenter, randomized, double-blind, placebo-controlled, parallel trial. Of the 663 screened volunteer patients with leg discomfort, a total of 516 men and women 40 years or older with a diagnosis of moderately severe chronic, stable, symptomatic intermittent claudication were randomized to receive cilostazol, 100 mg, cilostazol, 50 mg, or placebo twice a day orally for 24 weeks. Outcome measures included pain-free and maximal walking distances via treadmill testing, patient-based quality-of-life measures, global assessments by patient and physician, and cardiovascular morbidity and all-cause mortality survival analysis. RESULTS: The clinical and statistical superiority of active treatment over placebo was evident as early as week 4, with continued improvement at all subsequent time points. After 24 weeks, patients who received cilostazol, 100 mg, twice a day had a 51% geometric mean improvement in maximal walking distance (P<.001 vs placebo); those who received cilostazol, 50 mg, twice a day had a 38% geometric mean improvement in maximal walking distance (P<.001 vs placebo). These percentages translate into an arithmetic mean increase in distance walked, from 129.7 m at baseline to 258.8 m at week 24 for the cilostazol, 100 mg, group, and from 131.5 to 198.8 m for the cilostazol, 50 mg, group. Geometric mean change for pain-free walking distance increased by 59% (P<.001) and 48% (P<.001), respectively, in the cilostazol, 100 mg, and cilostazol, 50 mg, groups. These results were corroborated by the results of subjective quality-of-life assessments, functional status, and global evaluations. Headache, abnormal stool samples or diarrhea, dizziness, and palpitations were the most commonly reported potentially drug-related adverse events and were self-limited. A total of 75 patients (14.5%) withdrew because of any adverse event, which was equally distributed between all 3 treatment groups. Similarly, there were no differences between groups in the incidence of combined cardiovascular morbidity or all-cause mortality. CONCLUSION: Compared with placebo, long-term use of cilostazol, 100 mg or 50 mg, twice a day significantly improves walking distances in patients with intermittent claudication.

Effect of the novel antiplatelet agent cilostazol on plasma lipoproteins in patients with intermittent claudication.

Cilostazol is an antiplatelet agent and vasodilator marketed in Japan for treatment of ischemic symptoms of peripheral vascular disease. It is currently being evaluated in the United States for treatment of symptomatic intermittent claudication (IC). Cilostazol has been shown to improve walking distance in patients with IC. In addition to its reported vasodilator and antiplatelet effects, cilostazol has been proposed to have beneficial effects on plasma lipoproteins. We examined the effect of cilostazol versus placebo on plasma lipoproteins in 189 patients with IC. After 12 weeks of therapy with 100 mg cilostazol BID, plasma triglycerides decreased 15% (P<0.001). Cilostazol also increased plasma high density lipoprotein cholesterol (HDL-C) (10%) and apolipoprotein (apo) A1 (5.7%) significantly (P<0.001 and P<0.01, respectively). Both HDL3 and HDL2 subfractions were increased by cilostazol; however, the greatest percentage increase was observed in HDL2. Individuals with baseline hypertriglyceridemia (>140 mg/dL) experienced the greatest changes in both HDL-C and triglycerides with cilostazol treatment. In that subset of patients, HDL-C was increased 12.2% and triglycerides were decreased 23%. With cilostazol, there was a trend (3%) toward decreased apoB as well as increased apoA1, resulting in a significant (9.8%, P<0.002) increase in the apoA1 to apoB ratio. Low density lipoprotein cholesterol and lipoprotein(a) concentrations were unaffected. Cilostazol treatment resulted in a 35% increase in treadmill walking time (P=0.0015) and a 9.03% increase in ankle-brachial index (P<0.001). These results indicate that in addition to improving the symptoms of IC, cilostazol also favorably modifies plasma lipoproteins in patients with peripheral arterial disease. The mechanism of this effect is currently unknown.

Rapid identification of motile Aeromonas.

The clinical relevance and taxonomy of motile Aeromonas species are areas of current controversy. Strains of motile Aeromonas isolates (n = 60) from various sources were identified to species level using the following tests (all incubated at 30 degrees and 37 degrees C): esculin hydrolysis; formation of gas from glucose; production of acetoin; production of acid from mannitol and arabinose; decarboxylation of lysine and ornithine, dihydrolation of arginine; and pyrazinamide hydrolysis in a semisolid medium. The tests' results were similar at incubation temperatures of 30 degrees and 37 degrees C. Of the strains, 59 (98%) of 60 were identified to species level by the full battery of tests: 25 as A. hydrophila, 18 as A. caviae, 14 as A. sobria, one as A. veronii, and one as A. schubertii. (The only A. veronii and A. schubertii isolates identified were ATCC strains). All (25 of 25) strains of A. hydrophila and 17 (94%) of 18 of A. caviae hydrolyzed pyrazinamide in less than 24 hr, whereas all strains of A. sobria showed no pyrazinamidase activity. Absence of pyrazinamidase was, thus, a convenient phenotypic marker for A. sobria. Four additional tests (esculin hydrolysis, acetoin production, lysine decarboxylation, and gas production from glucose) identified within 24 hr all examples of the three common species of Aeromonas. Recently proposed species did not contribute to our ability to discriminate among stool, other clinical, and environmental isolates of Aeromonas spp.

Applying survival methodology to adverse experience occurrences in controlled clinical trials.

On the basis of calculated cumulative hazard rates for initial occurrence of adverse experiences of patients following treatment for rheumatoid arthritis and osteoarthritis, a simple function is evolved that fits such cumulative hazard rate data very well. From this simple function, we obtain the estimated hazard rate in terms of two physically meaningful parameters. These two parameters can be used to describe the rate of occurrence of adverse experiences, and to convey the concept of risk of adverse experience associated with duration of exposure to a drug. The parameters are rho 1, which represents the risk of adverse experience at baseline, and rho 2, which defines the rate of occurrence of adverse experience immediately following drug administration. A method of estimating rho 1 and rho 2 is the maximum likelihood approach, and the estimated parameters are given for series of data referring to patients treated for arthritis.

Testing for consistency in a single multicenter trial.

One of the criteria for demonstrating efficacy in a single multicenter trial is that the centers are consistent with respect to the direction and significance of results. The purpose of this research is to discuss the use of the noncentrality parameter delta of an F distribution as a means of testing for the consistency of treatment effects across centers. We state the testing problem as H0: (delta > delta 0) versus H1: (delta < or = delta 0), where delta 0 is prespecified, so that H0 represents inconsistency and H1 consistency. Thus, strong evidence from the sample data is required in order to conclude that the treatment effects are consistent across centers. We discuss reasonable choices for delta 0 and develop the alpha-level, uniformly most powerful and unbiased test, which is equivalent to rejecting H0 if the 100(1 - alpha)% uniformly most accurate and unbiased upper confidence limit for delta is less than or equal to delta 0. We examine other tests based on upper confidence limits, such as those calculated from linear estimators of delta and those calculated from a likelihood approach. We investigate the performance of the tests in a small simulation study and present an example from a four-center clinical trial.