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Dive into the research topics where Andrew C. Barrett is active.

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Featured researches published by Andrew C. Barrett.


Gastroenterology | 2015

Budesonide Foam Induces Remission in Patients With Mild to Moderate Ulcerative Proctitis and Ulcerative Proctosigmoiditis

William J. Sandborn; Brian P. Bosworth; Salam F. Zakko; Glenn L. Gordon; David R. Clemmons; Pamela L. Golden; Robert L. Rolleri; Jing Yu; Andrew C. Barrett; Enoch Bortey; Craig Paterson; William P. Forbes

BACKGROUND & AIMS Budesonide is a high-potency, second-generation corticosteroid designed to minimize systemic adverse consequences of conventional corticosteroids. We performed 2 randomized, phase 3 trials to evaluate the ability of budesonide rectal foam, formulated to optimize retention and provide uniform delivery of budesonide to the rectum and distal colon, to induce remission in patients with ulcerative proctitis or ulcerative proctosigmoiditis. METHODS Two identically designed, randomized, double-blind, placebo-controlled trials evaluated the efficacy of budesonide foam for induction of remission in 546 patients with mild to moderate ulcerative proctitis or ulcerative proctosigmoiditis who received budesonide foam 2 mg/25 mL twice daily for 2 weeks, then once daily for 4 weeks, or placebo. RESULTS Remission at week 6 occurred significantly more frequently among patients receiving budesonide foam than placebo (Study 1: 38.3% vs 25.8%; P = .0324; Study 2: 44.0% vs 22.4%; P < .0001). A significantly greater percentage of patients receiving budesonide foam vs placebo achieved rectal bleeding resolution (Study 1: 46.6% vs 28.0%; P = .0022; Study 2: 50.0% vs 28.6%; P = .0002) and endoscopic improvement (Study 1: 55.6% vs 43.2%; P = .0486; Study 2: 56.0% vs 36.7%; P = .0013) at week 6. Most adverse events occurred at similar frequencies between groups, although events related to changes in cortisol values were reported more frequently with budesonide foam. There were no cases of clinically symptomatic adrenal insufficiency. CONCLUSIONS Budesonide rectal foam was well tolerated and more efficacious than placebo in inducing remission in patients with mild to moderate ulcerative proctitis and ulcerative proctosigmoiditis. ClinicalTrials.gov ID: NCT01008410 and NCT01008423.


Hiv Clinical Trials | 2013

Efficacy and Safety of Crofelemer for Noninfectious Diarrhea in HIV-Seropositive Individuals (ADVENT Trial): A Randomized, Double-Blind, Placebo-Controlled, Two-Stage Study

Rodger D. MacArthur; Trevor Hawkins; Stephen Brown; Anthony LaMarca; Patrick G. Clay; Andrew C. Barrett; Enoch Bortey; Craig Paterson; Pamela L. Golden; William P. Forbes

Abstract Background: HIV-associated diarrhea remains a significant concern with limited treatment options. Objective: To determine the optimal dose, efficacy, and safety of crofelemer for noninfectious diarrhea. Methods: This randomized, double-blind, phase 3 trial used a 2-stage design. Both stages included 2-week screening, 4-week placebo-controlled treatment, and 20-week placebo-free (open-label) extension phases. In stage I, 196 HIV-seropositive patients with chronic diarrhea were randomized to crofelemer 125 mg, 250 mg, or 500 mg or placebo twice daily. Using a prospective analysis, the 125-mg twice-daily dose was selected for stage II. In stage II, 180 new patients were randomized to crofelemer 125 mg twice daily or placebo for 4 weeks. Primary efficacy analysis was the percentage of patients (stages I/II combined) who achieved clinical response (defined as ≤2 watery stools/week during ≥2 of 4 weeks). During the placebo-free extension phase, response (≤2 watery stools) was assessed weekly. Results: Significantly more patients receiving crofelemer 125 mg achieved clinical response versus placebo (17.6% vs 8.0%; one-sided, P = .01). Crofelemer 125 mg resulted in a greater change from baseline in number of daily watery bowel movements (P = .04) and daily stool consistency score (P = .02) versus placebo. During the placebo-free extension phase, percentages of weekly responders ranged from 40% to 56% at weeks 11 to 24. Crofelemer was minimally absorbed, well tolerated, did not negatively impact clinical immune parameters, and had a safety profile comparable to placebo. Conclusions: In HIV-seropositive patients taking stable antiretroviral therapy, crofelemer provided significant improvement in diarrhea with a favorable safety profile.


Alimentary Pharmacology & Therapeutics | 2015

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

Jasmohan S. Bajaj; Andrew C. Barrett; Enoch Bortey; Craig Paterson; William P. Forbes

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.


Journal of Palliative Medicine | 2015

Fixed-Dose Subcutaneous Methylnaltrexone in Patients with Advanced Illness and Opioid-Induced Constipation: Results of a Randomized, Placebo-Controlled Study and Open-Label Extension.

Janet Bull; Charles Wellman; Robert J. Israel; Andrew C. Barrett; Craig Paterson; William P. Forbes

Abstract Background: Subcutaneous methylnaltrexone (MNTX), dosed based on body weight, is efficacious and well tolerated in inducing bowel movements in patients with advanced illness and opioid-induced constipation (OIC); however, fixed-dose administration of MNTX may improve ease of administration. Objective: The study objective was to assess safety and efficacy of fixed-dose MNTX in two phase 4 trials. Methods: In a double-blind, randomized, placebo-controlled trial (RCT), patients with advanced illness and OIC received MNTX (8 mg or 12 mg by body weight [38 kg to <62 kg or ≥62 kg, respectively]) or placebo every other day (QOD) for two weeks. Patients completing the RCT could enroll in an open-label extension (OLE) study with MNTX administered as needed (PRN). The primary endpoint was percentage of patients with a rescue-free bowel movement (RFBM) within four hours after ≥2 of the first 4 doses in the first week. Results: In the RCT, 116 and 114 patients received MNTX and placebo, respectively, and 149 patients continued to the OLE study. The percentage of patients achieving primary endpoint was 62.9% and 9.6% for MNTX and placebo groups, respectively (p<0.0001). Median time to RFBM after the first dose was 0.8 hour and 23.6 hours in MNTX and placebo groups, respectively (p<0.0001). Efficacy results during the OLE study were consistent with the RCT. MNTX demonstrated a favorable safety profile in the RCT and OLE study. Conclusion: Fixed-dose MNTX administered QOD in the RCT and PRN in the OLE study demonstrated robust efficacy and was well tolerated in treating OIC in patients with advanced illness.


Regional Anesthesia and Pain Medicine | 2016

Efficacy and Safety of Methylnaltrexone for Opioid-Induced Constipation in Patients With Chronic Noncancer Pain: A Placebo Crossover Analysis.

Eugene R. Viscusi; Andrew C. Barrett; Craig Paterson; William P. Forbes

Background and Objectives In patients with chronic noncancer pain, subcutaneous methylnaltrexone for opioid-induced constipation (OIC) was examined in a randomized controlled trial (RCT) followed by an open-label extension (OLE). This study examined the reproducibility of RCT findings by analyzing data from placebo-treated patients who crossed over to methylnaltrexone. Methods Adults with less than 3 weekly rescue-free bowel movements (RFBMs), taking 50 mg or more of an oral morphine equivalent per day, were randomized to receive methylnaltrexone 12 mg or placebo for 4 weeks, followed by open-label methylnaltrexone 12 mg as needed for 8 weeks. Results A total of 134 placebo-treated patients (median morphine equivalent dose, 150 mg/d; mean of 1.1 RFBM per week) crossed over to methylnaltrexone in OLE. During the RCT, 9.7% of placebo-treated patients experienced an RFBM within 4 hours of first dose and 9.0% of all placebo injections resulted in an RFBM within 4 hours compared with 45.9% and 34.5%, respectively, with methylnaltrexone treatment in the OLE. When expressed as percentage of patients experiencing 3 or more RFBMs per week and a 1-RFBM increase over baseline, weekly values ranged from 35% to 40% during placebo treatment; at week 5 of OLE methylnaltrexone, this percentage increased to more than 70% and remained relatively stable throughout the OLE. The most common adverse events during methylnaltrexone treatment were abdominal pain (9.7% vs 1.5% for placebo) and nausea (5.2% vs 6.7%). Conclusions Findings during placebo treatment further establish the profile of OIC and support that little or no gastrointestinal tolerance develops across time. Findings under open-label conditions established the reproducibility and durability of methylnaltrexone for OIC.


Pain Practice | 2015

Efficacy and Tolerability of Subcutaneous Methylnaltrexone in Patients with Advanced Illness and Opioid-Induced Constipation: A Responder Analysis of 2 Randomized, Placebo-Controlled Trials.

Srinivas Nalamachu; Joseph V. Pergolizzi; Robert Taylor; Neal E. Slatkin; Andrew C. Barrett; Jing Yu; Enoch Bortey; Craig Paterson; William P. Forbes

Subcutaneous methylnaltrexone is efficacious and well tolerated in inducing bowel movements in patients with advanced illness and opioid‐induced constipation (OIC); factors determining optimal responsiveness to OIC treatment, however, have not been elucidated. This post hoc responder analysis examined the influence of demographic and baseline characteristics on methylnaltrexone efficacy and tolerability in this population.


Journal of Clinical Gastroenterology | 2016

Once-daily Mesalamine Formulation for Maintenance of Remission in Ulcerative Colitis: A Randomized, Placebo-controlled Clinical Trial.

Glenn L. Gordon; Salam F. Zakko; Uma K. Murthy; Shahriar Sedghi; Ronald E. Pruitt; Andrew C. Barrett; Enoch Bortey; Craig Paterson; William P. Forbes; Gary R. Lichtenstein

Goals: To evaluate the efficacy and safety of mesalamine granules 1.5 g once daily for maintenance of ulcerative colitis (UC) remission. Background: Mesalamine is a first-line treatment for induction and maintenance of UC remission. Study: A phase 3, randomized, double-blind, placebo-controlled trial of patients with a history of mild to moderate UC, currently in remission, who received mesalamine granules once daily for 6 months. The primary efficacy endpoint was percentage of patients maintaining UC remission at 6 months. Results: A significantly greater percentage of patients receiving mesalamine granules versus placebo were in remission at 6 months (79.9% vs. 66.7%; P=0.03). A greater percentage of patients receiving mesalamine granules maintained a revised Sutherland Disease Activity Index (SDAI)⩽2 with no individual component of revised SDAI>1 and rectal bleeding=0 at 6 months (72.0% vs. 58.1%; P=0.04). No significant differences between groups were observed for change from baseline to 6 months for total SDAI score or its components (ie, stool frequency, rectal bleeding, mucosal appearance, physician’s rating of disease). Mesalamine granules treatment resulted in a significantly longer remission duration versus placebo (P=0.02) and decreased patients’ risk of relapse by 43% (hazard ratio=0.57; 95% confidence interval, 0.35-0.93; P=0.02). Mesalamine granules were well tolerated, and adverse events related to hepatic, renal, and pancreatic function—potential concerns with long-term treatment—occurred at a rate similar to placebo. Conclusions: Once-daily mesalamine granules are efficacious and safe for the maintenance of UC remission.


Journal of Pain Research | 2015

Analysis of opioid-mediated analgesia in Phase III studies of methylnaltrexone for opioid-induced constipation in patients with chronic noncancer pain.

Lynn R Webster; Darren M. Brenner; Andrew C. Barrett; Craig Paterson; Enoch Bortey; William P. Forbes

Background Subcutaneous methylnaltrexone is efficacious and well tolerated for opioid-induced constipation (OIC) but may theoretically disrupt opioid-mediated analgesia. Methods Opioid use, pain intensity, and opioid withdrawal (Objective Opioid Withdrawal Scale [OOWS] and Subjective Opiate Withdrawal Scale [SOWS] scores) were reported in a randomized, double-blind trial with an open-label extension (RCT) and an open-label trial (OLT) evaluating safety in adults with chronic noncancer pain. In the RCT, patients taking ≥50 mg of oral morphine equivalents daily with <3 rescue-free bowel movements weekly received methyl naltrexone 12 mg once daily (n=150), every other day (n=148), or placebo (n=162) for 4 weeks, followed by open-label methylnaltrexone 12 mg (as needed [prn]; n=364) for 8 weeks. In the OLT, patients (n=1,034) on stable opioid doses with OIC received methylnaltrexone 12 mg prn for up to 48 weeks. Results Minimal fluctuations of median morphine equivalent dose from baseline (BL) were observed in the RCT double-blind period (BL, 154.8–161.0 mg/d; range, 137.1–168.0 mg/d), RCT open-label period (BL, 156.3–174.6; range, 144.0–180.0) and OLT (BL, 120 mg/d; range, 117.3–121.1 mg/d). No significant change from BL in pain intensity score occurred in any group at weeks 2 or 4 (both P≥0.1) of the RCT double-blind period, and scores remained stable during the open-label period and in the OLT (mean change, −0.2 to 0.1). Changes from BL in OOWS and SOWS scores during the double-blind period were not significantly impacted by methylnaltrexone exposure at weeks 2 or 4 (P>0.05 for all). Conclusion Methylnaltrexone did not affect opioid-mediated analgesia in patients with chronic noncancer pain and OIC.


Journal of Crohns & Colitis | 2017

Budesonide Multimatrix Is Efficacious for Mesalamine-refractory, Mild to Moderate Ulcerative Colitis: A Randomised, Placebo-controlled Trial

David T. Rubin; Russell D. Cohen; William J. Sandborn; Gary R. Lichtenstein; Jeffrey L. Axler; Robert H. Riddell; Cindy Zhu; Andrew C. Barrett; Enoch Bortey; William P. Forbes

Abstract Background and Aims: Safety and efficacy of budesonide multimatrix, an oral extended-release second-generation corticosteroid designed for targeted delivery throughout the colon, were examined for induction of remission in patients with mild to moderate ulcerative colitis refractory to baseline mesalamine therapy. Methods: A randomised, double-blind, placebo-controlled, multicentre trial evaluated efficacy and safety of budesonide multimatrix for induction of remission [ulcerative colitis disease activity index score ≥ 4 and ≤ 10] in 510 adults randomised to once-daily oral budesonide multimatrix 9 mg or placebo for 8 weeks. Patients continued baseline treatment with oral mesalamine ≥ 2.4 g/day. Results: Combined clinical and endoscopic remission at Week 8 was achieved by 13.0% and 7.5% of patients receiving budesonide multimatrix [n = 230] or placebo [n = 228], respectively, in the modified intention-to-treat population [p = 0.049]. Clinical remission [ulcerative colitis disease activity index rectal bleeding and stool frequency subscale scores of 0] was similar in both groups [p = 0.70]. More patients receiving budesonide multimatrix vs placebo achieved endoscopic remission [ulcerative colitis disease activity index mucosal appearance subscale score of 0; 20.0% vs 12.3%; p = 0.02] and histological healing [27.0% vs 17.5%; p = 0.02]. Adverse event rates were similar [budesonide multimatrix, 31.8%; placebo, 27.1%]. Mean morning cortisol concentrations decreased at Weeks 2, 4, and 8 with budesonide multimatrix but remained within the normal range. Conclusion: Budesonide multimatrix was safe and efficacious for inducing clinical and endoscopic remission for mild to moderate ulcerative colitis refractory to oral mesalamine therapy.


Postgraduate Medicine | 2016

Once-daily mesalamine granules for maintaining remission of ulcerative colitis: pooled analysis of efficacy, safety, and prognostic factors

Salam F. Zakko; Glenn L. Gordon; Uma K. Murthy; Shahriar Sedghi; Ronald E. Pruitt; Andrew C. Barrett; Enoch Bortey; Craig Paterson; William P. Forbes; Gary R. Lichtenstein

ABSTRACT Objectives: A capsule formulation of mesalamine granules (MG) was developed for once-daily dosing and better compliance. The study aim was to evaluate MG efficacy and tolerability in maintaining ulcerative colitis (UC) remission. Methods: Pooled analysis of 2 identical phase 3, randomized, double-blind trials of once-daily MG 1.5 g or placebo for up to 6 months. The primary endpoint was percentage of patients remaining relapse-free at month 6 versus placebo. Relapse was defined as revised Sutherland Disease Activity Index (SDAI) rectal bleeding score ≥1 and mucosal appearance score ≥2, UC flare, or UC–related adverse event (AE). Results: Data were pooled for patients receiving MG (n = 373) and placebo (n = 189). Significantly more patients were relapse-free at 6 months with MG (79.4%) than placebo (62.4%; P < 0.001) and across subgroups based on select demographic and baseline characteristics (P < 0.05). Secondary outcome measures including rectal bleeding, physician rating of disease activity, stool frequency, total SDAI score, and relapse-free duration favored MG (P < 0.01). Common AEs with MG and placebo, respectively, were headache (10.9% and 7.6%), diarrhea (7.9% and 7.0%), and abdominal pain (6.3% and 6.5%). Conclusion: Once-daily MG was more efficacious than and as well tolerated as placebo in maintaining UC remission. ClinicalTrials.gov identifiers: NCT00744016 and NCT00767728.

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Salam F. Zakko

University of Connecticut

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Jing Yu

Salix Pharmaceuticals

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