Importance of data management with statistical analysis set division

Testing of hypothesis was affected by statistical analysis set division which was an important data management work before data base lock-in. Objective division of statistical analysis set under blinding was the guarantee of scientific trial conclusion. All the subjects having accepted at least once trial treatment after randomization should be concluded in safety set. Full analysis set should be close to the intention-to-treat as far as possible. Per protocol set division was the most difficult to control in blinded examination because of more subjectivity than the other two. The objectivity of statistical analysis set division must be guaranteed by the accurate raw data, the comprehensive data check and the scientific discussion, all of which were the strict requirement of data management. Proper division of statistical analysis set objectively and scientifically is an important approach to improve the data management quality.

[Prevention and handling of missing data in clinical trials]

Missing data is a common but unavoidable issue in clinical trials. It not only lowers the trial power, but brings the bias to the trial results. Therefore, on one hand, the missing data handling methods are employed in data analysis. On the other hand, it is vital to prevent the missing data in the trials. Prevention of missing data should take the first place. From the perspective of data, firstly, some measures should be taken at the stages of protocol design, data collection and data check to enhance the patients' compliance and reduce the unnecessary missing data. Secondly, the causes of confirmed missing data in the trials should be notified and recorded in detail, which are very important to determine the mechanism of missing data and choose the suitable missing data handling methods, e.g., last observation carried forward (LOCF); multiple imputation (MI); mixed-effect model repeated measure (MMRM), etc.

Immunity and clinical efficacy of an inactivated enterovirus 71 vaccine in healthy Chinese children: a report of further observations

BACKGROUND

To investigate the long-term effects on immunity of an inactivated enterovirus 71 (EV71) vaccine and its protective efficacy.

METHODS

A sub-cohort of 1,100 volunteers from Guangxi Province in China was eligible for enrolment and randomly administered either the EV71 vaccine or a placebo on days 0 and 28 in a phase III clinical trial and then observed for the following 2 years with approval by an independent ethics committee of Guangxi Zhuang Autonomous Region, China. Serum samples from the 350 participants who provided a full series of blood samples (at all the sampling points) within the 2-year period were collected. Vaccine-induced immune effects, including the neutralizing antibody titres and cross-protection against different genotypes of EV71, were examined. This study also evaluated the protective efficacy of this vaccine based upon clinical diagnosis.

RESULTS

This sub-cohort showed a >60% drop-out rate over 2 years. The seroconversion rates among the 161 immunized subjects remained >95% at the end of study. The geometric mean titres of neutralizing antibodies (anti-genotype C4) 360 days after vaccination in 350 subjects were 81.0 (subjects aged 6-11 months), 98.4 (12-23 months), 95.0 (24-35 months), and 81.8 (36-71 months). These titres subsequently increased to 423.1, 659.0, 545.0, and 321.9, respectively, at 540 days post-immunization (d.p.i.), and similar levels were maintained at 720 d.p.i. Higher IFN-γ/IL-4-specific responses to the C4 genotype of EV71 and cross-neutralization reactivity against major EV71 genotype strains were observed in the vaccine group compared to those in the placebo group. Five EV71-infected subjects were observed in the placebo-treated control group and none in the vaccine-immunized group in per-protocol analysis.

CONCLUSION

These results are consistent with the induction of dynamic immune responses and protective efficacy of the vaccine against most circulating EV71 strains.

TRIAL REGISTRATION NUMBER

Clinicaltrials.gov, NCT01569581, Trial registration date: March 2012.

An open-label, randomized, multicenter dose-finding study of once-per-cycle pegfilgrastim versus daily filgrastim in Chinese breast cancer patients receiving TAC chemotherapy

A chemotherapy regimen of docetaxel, doxorubicin and cyclophosphamide (TAC) has been accepted as a standard care because of their superior clinical benefit in early-stage breast cancer patients, but with a higher risk of neutropenia. Pegfilgrastim is a once-per-cycle therapy for prophylactic neutrophil support and neutropenia prevention. There was still a lack of direct evidences for finding an optimal fixed dose of pegfilgrastim in Chinese breast cancer patients receiving TAC regimen. An open-label, randomized, phase II study was designed to compare the effects of pegfilgrastim with filgrastim. Eighteen centers in China enrolled 171 eligible female breast cancer patients with cycles of TAC chemotherapy treatment, randomized into four arms, received a single subcutaneous injection of pegfilgrastim (60, 100 or 120 µg/kg) per chemotherapy cycle or daily subcutaneous injections of filgrastim 5 µg/kg 24 h after chemotherapy. Efficacy and safety were analyzed. In ITT population, the mean duration of grade 3+ neutropenia (neutrophil count <1.0 × 10(9)/l) was 2.09, 1.53 and 1.73 days in patients who received pegfilgrastim 60, 100 and 120 µg/kg/cycle, respectively, and 1.69 days in patients who received 5 µg/kg/day filgrastim (P = 0.043). The incidence of grade 3+ neutropenia was 76, 83 and 74 % for doses of pegfilgrastim and 90 % for filgrastim (P = 0.409). The results for febrile neutropenia, time to neutrophil recovery and neutrophil profile were also not significantly different between arms. The safety profiles of pegfilgrastim and filgrastim were similar. A single dose of 100 µg/kg once-per-cycle administration of pegfilgrastim provided neutrophil support and a safety profile comparable to daily subcutaneous injections of filgrastim in Chinese breast cancer patients receiving TAC chemotherapy.

Bridging continual reassessment method for phase I clinical trials in different ethnic populations

Accumulating evidence shows that the conventional one-size-fits-all dose-finding paradigm is problematic when applied to different ethnic populations. Because of inter-ethnic heterogeneity, the dosage established in a landmark trial for a certain population may not be generalizable to a different ethnic population, and a follow-up bridge trial is often needed to find the maximum tolerated dose for the new population. We propose the bridging continual reassessment method (B-CRM) to facilitate dose finding for such follow-up bridge trials. The B-CRM borrows information from the landmark trial through a novel estimate of the dose-toxicity curve and accommodates the inter-ethnic heterogeneity using the Bayesian model averaging approach. Extensive simulation studies show that the B-CRM has desirable operating characteristics with a high probability to select the target dose. This article focuses on ethnic heterogeneity, but the proposed method can be directly used to handle other types of patient heterogeneity, for example, patient subgroups defined by prognostic factors or biomarkers. The software to implement the B-CRM design is available for free download at http://odin.mdacc.tmc.edu/~yyuan/.

CP function: an alpha spending function based on conditional power

Alpha spending function and stochastic curtailment are two frequently used methods in group sequential design. In the stochastic curtailment approach, the actual type I error probability cannot be well controlled within the specified significance level. But conditional power (CP) in stochastic curtailment is easier to be accepted and understood by clinicians. In this paper, we develop a spending function based on the concept of conditional power, named CP function, which combines desirable features of alpha spending and stochastic curtailment. Like other two-parameter functions, CP function is flexible to fit the needs of the trial. A simulation study is conducted to explore the choice of CP boundary in CP function that maximizes the trial power. It is equivalent to, even better than, classical Pocock, O'Brien-Fleming, and quadratic spending function as long as a proper ρ0 is given, which is pre-specified CP threshold for efficacy. It also well controls the overall type I error type I error rate and overcomes the disadvantage of stochastic curtailment.

On-chip generation and manipulation of entangled photons based on reconfigurable lithium-niobate waveguide circuits

A consequent tendency toward high-performance quantum information processing is to develop the fully integrated photonic chip. Here, we report the on-chip generation and manipulation of entangled photons based on reconfigurable lithium-niobate waveguide circuits. By introducing a periodically poled structure into the waveguide circuits, two individual photon-pair sources with a controllable electro-optic phase shift are produced within a Hong-Ou-Mandel interferometer, resulting in a deterministically separated identical photon pair. The state is characterized by 92.9±0.9% visibility Hong-Ou-Mandel interference. The photon flux reaches ∼1.4×10(7)  pairs nm-1 mW-1. The whole chip is designed to contain nine similar units to produce identical photon pairs spanning the telecom C and L band by the flexible engineering of nonlinearity. Our work presents a scenario for on-chip engineering of different photon sources and paves the way to fully integrated quantum technologies.

Efficacy, safety, and immunogenicity of an enterovirus 71 vaccine in China

BACKGROUND

Enterovirus 71 (EV71) is one of the major causative agents of outbreaks of hand, foot, and mouth disease or herpangina worldwide. This phase 3 trial was designed to evaluate the efficacy, safety, and immunogenicity of an EV71 vaccine.

METHODS

We conducted a randomized, double-blind, placebo-controlled, multicenter trial in which 10,007 healthy infants and young children (6 to 35 months of age) were randomly assigned in a 1:1 ratio to receive two intramuscular doses of either EV71 vaccine or placebo, 28 days apart. The surveillance period was 12 months. The primary end point was the occurrence of EV71-associated hand, foot, and mouth disease or herpangina.

RESULTS

During the 12-month surveillance period, EV71-associated disease was identified in 0.3% of vaccine recipients (13 of 5041 children) and 2.1% of placebo recipients (106 of 5028 children) in the intention-to-treat cohort. The vaccine efficacy against EV71-associated hand, foot, and mouth disease or herpangina was 94.8% (95% confidence interval [CI], 87.2 to 97.9; P<0.001) in this cohort. Vaccine efficacies against EV71-associated hospitalization (0 cases vs. 24 cases) and hand, foot, and mouth disease with neurologic complications (0 cases vs. 8 cases) were both 100% (95% CI, 83.7 to 100 and 42.6 to 100, respectively). Serious adverse events occurred in 111 of 5044 children in the vaccine group (2.2%) and 131 of 5033 children in the placebo group (2.6%). In the immunogenicity subgroup (1291 children), an anti-EV71 immune response was elicited by the two-dose vaccine series in 98.8% of participants at day 56. An anti-EV71 neutralizing antibody titer of 1:16 was associated with protection against EV71-associated hand, foot, and mouth disease or herpangina.

CONCLUSIONS

The EV71 vaccine provided protection against EV71-associated hand, foot, and mouth disease or herpangina in infants and young children. (Funded by Sinovac Biotech; ClinicalTrials.gov number, NCT01507857.).

An inactivated enterovirus 71 vaccine in healthy children

BACKGROUND

Enterovirus 71 (EV71) is a major cause of hand, foot, and mouth disease in children and may be fatal. A vaccine against EV71 is needed.

METHODS

We conducted a randomized, double-blind, placebo-controlled phase 3 trial involving healthy children 6 to 71 months of age in Guangxi Zhuang Autonomous Region, China. Two doses of an inactivated EV71 vaccine or placebo were administered intramuscularly, with a 4-week interval between doses, and children were monitored for up to 11 months. The primary end point was protection against hand, foot, and mouth disease caused by EV71.

RESULTS

A total of 12,000 children were randomly assigned to receive vaccine or placebo. Serum neutralizing antibodies were assessed in 549 children who received the vaccine. The seroconversion rate was 100% 4 weeks after the two vaccinations, with a geometric mean titer of 170.6. Over the course of two epidemic seasons, the vaccine efficacy was 97.4% (95% confidence interval [CI], 92.9 to 99.0) according to the intention-to-treat analysis and 97.3% (95% CI, 92.6 to 99.0) according to the per-protocol analysis. Adverse events, such as fever (which occurred in 41.6% of the participants who received vaccine vs. 35.2% of those who received placebo), were significantly more common in the week after vaccination among children who received the vaccine than among those who received placebo.

CONCLUSIONS

The inactivated EV71 vaccine elicited EV71-specific immune responses and protection against EV71-associated hand, foot, and mouth disease. (Funded by the National Basic Research Program and others; ClinicalTrials.gov number, NCT01569581.).

EASL- and mRECIST-evaluated responses to combination therapy of sorafenib with transarterial chemoembolization predict survival in patients with hepatocellular carcinoma

PURPOSE

Published studies have not investigated the suitability of Response Evaluation Criteria in Solid Tumors (RECIST), European Association for the Study of the Liver (EASL) criteria, and modified RECIST (mRECIST) for assessing the response of patients with hepatocellular carcinoma to treatment with sorafenib combined with transarterial chemoembolization. Here, we aimed to define the earliest time at which the response to combination therapy could be accurately assessed and validate the prognostic value of these criteria at this early posttherapy time point.

EXPERIMENTAL DESIGN

A total of 114 consecutive patients with hepatocellular carcinoma receiving combination therapy were retrospectively enrolled. The therapy response at different time points was assessed using RECIST, EASL, and mRECIST. Cox regression analysis and Kaplan-Meier curves were used to assess overall survival (OS) in the responders and nonresponders.

RESULTS

At the third follow-up (median, 94 days; range, 89-102 days) after therapy, the response rates obtained using EASL (50.6%) and mRECIST (51.6%) were greater than that obtained using RECIST (16.5%). The agreement was strong between the mRECIST and EASL results (k = 0.9) but weak between mRECIST and RECIST (k = 0.3). The EASL and mRECIST responses significantly correlated with survival. Risk reductions of 52% and 50% were observed for EASL and mRECIST responders, respectively, compared with nonresponders. However, no significant association between the treatment response and survival was observed using RECIST.

CONCLUSIONS

The earliest time to evaluate the response to combination therapy is 3 months (median, 94 days) after therapy. EASL and mRECIST responses are independent predictors for OS at this early time point.

A phase I/II seamless dose escalation/expansion with adaptive randomization scheme (SEARS)

BACKGROUND

Standard drug development conducts phase I dose finding and phase II dose expansion sequentially and separately. Information between the two phases is rarely shared. Administratively, such a sequential process is time-consuming and burdensome.

PURPOSE

We propose seamless dose escalation/expansion with adaptive randomization scheme (SEARS), a seamless design that combines phase I dose escalation based on toxicity with phase II dose expansion and dose comparison based on efficacy. SEARS allows extension from phase I to phase II under one design with no gap in between and employs a dynamic and parallel procedure involving simultaneous dose escalation, dose graduation, and adaptive randomization.

METHODS

SEARS integrates three components into a seamless scheme. Specifically, in phase I, SEARS applies the modified toxicity probability interval (mTPI) method to monitor dose escalation based on toxicity outcome. Doses that show promising efficacy and safety are immediately graduated from phase I and placed to a phase II stage in which patients are adaptively randomized based on efficacy outcome. Phase I dose escalation, dose graduation, and phase II adaptive randomization proceed simultaneously throughout the entire trial.

RESULTS

Examples are given comparing SEARS with two other designs, in which superior performance of SEARS is demonstrated. An important and promising finding is that SEARS reduces sample sizes without losing power. R program and demo slides of SEARS can be obtained at http://health.bsd.uchicago.edu/yji/soft.html

LIMITATION

We assume that the binary efficacy and toxicity response can be measured in the same time frame. This is often achievable with surrogate efficacy markers in practice.

Optimal caliper width for propensity score matching of three treatment groups: a Monte Carlo study

Propensity score matching is a method to reduce bias in non-randomized and observational studies. Propensity score matching is mainly applied to two treatment groups rather than multiple treatment groups, because some key issues affecting its application to multiple treatment groups remain unsolved, such as the matching distance, the assessment of balance in baseline variables, and the choice of optimal caliper width. The primary objective of this study was to compare propensity score matching methods using different calipers and to choose the optimal caliper width for use with three treatment groups. The authors used caliper widths from 0.1 to 0.8 of the pooled standard deviation of the logit of the propensity score, in increments of 0.1. The balance in baseline variables was assessed by standardized difference. The matching ratio, relative bias, and mean squared error (MSE) of the estimate between groups in different propensity score-matched samples were also reported. The results of Monte Carlo simulations indicate that matching using a caliper width of 0.2 of the pooled standard deviation of the logit of the propensity score affords superior performance in the estimation of treatment effects. This study provides practical solutions for the application of propensity score matching of three treatment groups.

A novel Bayesian seamless phase I/II design

This paper proposes a novel bayesian phase I/II design featuring using a hybrid mTPI method in phase I for targeting the MTD level and a randomization allocation schema for adaptively assigning patients to desirable doses in phase II. The mechanism of simultaneously escalating dose in phase I and expanding promising doses to phase II is inherited from a design proposed in literature. Extensive simulation studies indicate that our proposed design can vastly save sample size and efficiently assign more patients to optimal dose when compared to two competing designs.

Percutaneous recanalization for Budd-Chiari syndrome: an 11-year retrospective study on patency and survival in 177 Chinese patients from a single center

PURPOSE

To evaluate the long-term outcomes of percutaneous recanalization and determine the predictors of patency and survival in a large case series of Chinese patients with Budd-Chiari syndrome (BCS).

MATERIALS AND METHODS

This retrospective study was approved by the institutional ethics committee. Informed consent for the procedure was obtained from all patients. Between July 1999 and August 2010, 177 consecutive Chinese patients with primary BCS were treated with percutaneous recanalization and followed up until death or their last clinical evaluation. Recanalization therapeutic strategy and complications were recorded. Cumulative patency and survival rates were assessed with Kaplan-Meier curves. Independent predictors of patency and survival were calculated with the Cox regression model.

RESULTS

Percutaneous recanalization was technically successful in 168 of the 177 patients (95%). Fifty-one of the 168 patients (30%) were treated with percutaneous transluminal angioplasty (PTA) alone and 117 (70%) were treated with a combination of PTA and stent placement. Procedure-related complications occurred in seven of the 168 patients (4%). The cumulative 1-, 5-, and 10-year primary patency rates were 95%, 77%, and 58%, respectively. Independent predictors of reocclusion included increased white blood cell count and use of PTA alone. The cumulative 1-, 5-, and 10-year secondary patency rates were 97%, 90%, and 86%, respectively. Twenty-two patients died during a median follow-up of 30 months (range, 0.25-137 months). The cumulative 1-, 5-, and 10-year survival rates were 96%, 83%, and 73%, respectively. Independent predictors of survival included variceal bleeding, increased alkaline phosphatase and blood urea nitrogen levels, and reocclusion.

CONCLUSION

Percutaneous recanalization could achieve excellent long-term patency and survival in most Chinese patients with BCS. PTA combined with stent placement should be recommended to decrease the frequency of reocclusion and its associated mortality.

Transjugular intrahepatic portosystemic shunt for the prevention of variceal rebleeding in cirrhotic patients with portal vein thrombosis: study protocol for a randomised controlled trial

INTRODUCTION

Portal vein thrombosis (PVT) increases the risk of variceal rebleeding in liver cirrhosis. However, the strategy for preventing variceal rebleeding in cirrhotic patients with PVT has not been explored. This study aims to evaluate whether the transjugular intrahepatic portosystemic shunt (TIPS) or conventional therapy is preferable for the prevention of variceal rebleeding in liver cirrhosis patients with PVT.

METHODS AND ANALYSIS

This is a randomised controlled trial comparing the safety and efficacy of TIPS versus conventional therapy (ie, endoscopic therapy combined with non-selective β-blockers and anticoagulants) for the prevention of variceal rebleeding in cirrhotic patients with non-tumoral PVT. A total of 50 cirrhotic patients with PVT (thrombus >50% of portal vein lumen occupancy) and a history of variceal bleeding will be stratified according to the Child-Pugh class and degree of PVT, and randomised into the TIPS and conventional therapy groups. The primary objective was to compare the incidence of variceal rebleeding between the two groups. The secondary objectives were to compare the overall mortality, variceal rebleeding-related mortality, portal vein recanalisation and complications between the two groups, and to observe the progression of PVT in patients without portal vein recanalisation.

ETHICS AND DISSEMINATION

This study was approved by the ethics committee of Xijing hospital (No. 20110224-5), and was registered at ClinicalTrials.gov (NCT01326949). All participants give written informed consent. The first patient was recruited into our study on 4 June 2011. A total of 29 patients were recruited through 5 March 2013 (14 and 15 patients assigned to the TIPS and conventional therapy groups, respectively). If TIPS is superior to conventional therapy for the prevention of variceal rebleeding in cirrhotic patients with PVT, TIPS might be recommended as the first-line therapy in such patients. But a small sample size potentially limits the generalisation of our conclusions.

TRIAL REGISTRATION

This study was registered at ClinicalTrials.gov on 29 March 2011. The trial registration number is NCT01326949.

TRIAL STATUS

The first patient was recruited into our study on 4 June 2011. A total of 29 patients were recruited through 5 March 2013 (14 and 15 patients assigned to the TIPS and conventional therapy groups, respectively).

Helicobacter pylori eradication with ecabet sodium, omeprazole, amoxicillin, and clarithromycin versus bismuth, omeprazole, amoxicillin, and clarithromycin quadruple therapy: a randomized, open-label, phase IV trial

BACKGROUND

Helicobacter pylori infection is a substantial public health problem and plays etiological role in the pathogenesis of many gastroduodenal disorders. The addition of ecabet sodium is proven to improve the efficacy of the standard triple therapy. Our aim was to assess the efficacy and safety of ecabet sodium-containing quadruple therapy versus 10-day bismuth-containing quadruple therapy for H. pylori eradication.

MATERIALS AND METHODS

We did a randomized, open-label, phase IV trial in four cities (eight sites) in China, comparing the efficacy and safety of 10-days ecabet sodium-containing versus bismuth-containing quadruple therapy in adults with H. pylori infection. Eligible patients were randomly assigned treatment and monitored H. pylori eradication by negative [13C]/[14C] urea breath test 28 days after the treatment as the primary outcome. Symptoms improvement and side effects were the secondary outcome.

RESULTS

A total of 311 H. pylori-positive subjects were enrolled: 155 were assigned ecabet sodium quadruple therapy and 156 bismuth quadruple therapy. The eradication rates with ecabet sodium-containing and bismuth-containing quadruple regimens were 68.4% (106/155) and 68.0% (106/156) p = .9339 intention-to-treat (ITT) and 75.4% (104/138) and 77.0% (104/135) p = .7453 per-protocol (PP), respectively. The eradication rates for the ecabet sodium quadruple regimen differed significantly between cities (e.g., 81.2% ITT and 89.6% PP in Shanghai and 50% ITT and 53.5% PP in Xi'an). The symptom improvements and safety profiles were also similar for both treatments.

CONCLUSIONS

Neither 10-day Ecabet sodium-containing quadruple therapy or 10-day bismuth-containing quadruple therapy can be recommended as empiric therapy in cities with high antibiotic resistance rate of China.

Transjugular intrahepatic portosystemic shunt may be superior to conservative therapy for variceal rebleeding in cirrhotic patients with non-tumoral portal vein thrombosis: a hypothesis

The presence of occlusive portal vein thrombosis (PVT) greatly changes the natural history of liver cirrhosis, because it not only significantly increases the incidence of variceal rebleeding but also negatively influences the survival. However, due to the absence of strong evidence, no standard treatment algorithm for the secondary prophylaxis of variceal bleeding in cirrhotic patients with non-tumoral PVT has been established. Previous randomized controlled trials have demonstrated that transjugular intrahepatic portosystemic shunt (TIPS) can significantly decrease the incidence of variceal rebleeding in cirrhotic patients without PVT, compared with conservative therapy (i.e., endoscopic plus pharmacological therapy). Further, several large cohort studies have confirmed that TIPS can effectively prevent variceal rebleeding in cirrhotic patients with non-tumoral PVT. On the other hand, TIPS can facilitate recanalizing the thrombosed portal vein by endovascular manipulations, even in the presence of cavernous transformation of the portal vein (CTPV). More importantly, successful TIPS insertions can maintain the persistent portal vein patency, and avoid thrombus extension into the portal venous system. By comparison, anticoagulation therapy can achieve portal vein recanalization only in patients with partial PVT, but not in those with occlusive PVT or CTPV, and the use of anticoagulants may aggravate the risk of variceal bleeding in cirrhotic patients with a history of variceal bleeding. Collectively, we hypothesize that TIPS may be superior to conservative therapy for the prevention of variceal rebleeding in cirrhotic patients with non-tumoral PVT. Randomized controlled trials should be conducted to evaluate the survival benefit of TIPS in these patients.

Ilaprazole for the treatment of duodenal ulcer: a randomized, double-blind and controlled phase III trial

OBJECTIVE

The new proton pump inhibitor (PPI), ilaprazole performed better at the dose of 10 mg/d relative to 5 or 20 mg/d in a previous phase II trial. A larger phase III trial was carried out to confirm the efficacy and safety of ilaprazole (10 mg/d) compared with omeprazole (20 mg/d) and provide some characteristics of the relationship between ilaprazole metabolism and CYP2C19 for later studies.

RESEARCH DESIGN AND METHODS

Patients with at least one endoscopically diagnosed active duodenal ulcer (DU) were enrolled in a multicenter, randomized, double-blind, positive controlled trial and then assigned randomly to the ilaprazole group (10 mg/d) or the omeprazole group (20 mg/d) with a sample allocation ratio 2:1. The course of treatment was 4 weeks.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov registration number: NCT00952978.

MAIN OUTCOME MEASURES

The primary endpoint was endoscopically diagnosed ulcer healing rate at week 4. Symptom relief was evaluated as a secondary endpoint by graded scores. Safety and tolerability were evaluated on basis of clinical assessments. In addition, blood samples were collected at baseline for CYP2C19 genotypes identification.

RESULTS

Efficacy analyses were based on 494 patients. At week 4, the ulcer healing rates were 93.0% in ilaprazole group and 90.8% in omeprazole group (rate difference: 2.2%; 95% confidence interval: -2.8% to 7.2%). No obvious variation of healing rate on different CYP2C19 genotypes was found in ilaprazole group. The majority of patients (>80%) became asymptomatic after treatment. Incidences of adverse drug reactions were similar between ilaprazole group and omeprazole group (8.5% vs. 11.5%).

CONCLUSIONS

Ilaprazole (10 mg/d) is as effective as omeprazole (20 mg/d) in the treatment of DU with similar side effects. The efficacy of ilaprazole is not affected by CYP2C19 polymorphisms.

A SAS macro for target dose estimation by reinforced urn processes in phase I clinical trials

The reinforced urn processes (RUPs) approach can estimate the target dose on the basis of the prior distribution function precisely and conveniently without the requirements about the explicit-estimated dose-response curve and the posterior complicated inference. The application of the RUPs approach was not discussed from the perspective of phase I clinical trial in the previous studies which just focused on the theory and methodology. And the modification of the traditional RUPs design should be considered for the purposes of ethnics and efficiency. A SAS macro was designed to explore the appropriate parameter settings according to the simulation outcomes in different situations and apply the RUPs approach for two state processes in phase I clinical trail with the modified RUPs design. The posterior estimation can be obtained precisely and efficiently with application of SAS program following the appropriate workflow and determination rule which were described in the example.

Transjugular intrahepatic portosystemic shunt for portal vein thrombosis with symptomatic portal hypertension in liver cirrhosis

BACKGROUND & AIMS

Data on the management of portal vein thrombosis (PVT) in patients with decompensated cirrhosis are extremely limited, particularly in the cases of the transjugular intrahepatic portosystemic shunt (TIPS). We assessed the outcome of TIPS for PVT in patients with cirrhosis and symptomatic portal hypertension and determined the predictors of technical success and survival.

METHODS

In the retrospective study, 57 consecutive patients receiving TIPS were enrolled between December 2001 and September 2008. All were diagnosed with chronic PVT, and 30 had portal cavernoma. Indications for TIPS were variceal hemorrhage (n = 56) and refractory ascites (n = 1).

RESULTS

TIPS were successfully placed in 75% of patients (43/57). The independent predictors of technical success included portal cavernoma, and the degree of thrombosis within the main portal vein (MPV), the portal vein branches, and the superior mesenteric vein. Only one patient died of severe procedure-related complication. The cumulative 1-year shunt dysfunction and hepatic encephalopathy rates were 21% and 25%, respectively. The cumulative 1- and 5-year variceal re-bleeding rates differed significantly between the TIPS success and failure groups (10% and 28% versus 43% and 100%, respectively; p = 0.0004), while the cumulative 1- and 5-year survival rates were similar between the two groups (86% and 77% versus 78% and 62%, respectively; p = 0.34). The independent predictor of survival in PVT patients with decompensated cirrhosis was the degree of MPV occlusion (hazard ratio 0.189, 95% CI 0.042-0.848).

CONCLUSIONS

TIPS should be considered a safe and feasible alternative therapy for chronic PVT in selected patients with decompensated cirrhosis. Both technical success and survival were closely associated with the degree of MPV occlusion.