Mesalamine or 5-aminosalicylic acid (5-ASA) and its isomer 4-aminosalicylic acid (4-ASA), well known key therapeutic agents used to treat inflammatory bowel diseases (IBDs) can pose toxicity risks upon unregulated consumption. However, their simultaneous real-time detection from physiological fluids like urine remains unexplored. This study presents an innovative electrochemical sensing platform using modified screen-printed electrodes capable of simultaneous detection of both the drugs by harnessing the synergistic potential of a novel nanocomposite comprising chitosan functionalized multi-walled carbon nanotubes and nickel doped bismuth sulphide. Comprehensive optical and microstructural characterization validate the modified sensor platform's morphological characteristics. The sensor was evaluated using CV and DPV, exhibiting notably low detection limits which is of the value 39.559 μM for 5-ASA and 85.21 μM for 4-ASA. Sensitivity was found to be 0.174 μA μM-1cm-2 for the linear dynamic range (LDR) of 50 μM-5750 μM for 5-ASA and 0.139 μA μM-1cm-2 for the linear dynamic range (LDR) of 100 μM-2200 μM for 4-ASA. Moreover, the adaptability of the sensor for integration into hand-held point-of-care devices for practical application has been demonstrated in this paper. Experimental validation using real urine samples underscores the sensor's impressive recovery rate of 98-99.6 % for 5-ASA and 95.12-99.24 % for 4-ASA and its capability of detecting target drugs even when present with typical urinary constituents as interferences. The real-world applicability of this sensing platform is further emphasized by conducting experiments on miniaturized hand-held device thus making it a promising tool for on-the-spot detection, offering substantial potential for future integration into point-of-care diagnostic devices to monitor patients requiring precise medical monitoring. Our approach offers unprecedented real-time identification capabilities of 4-ASA and 5-ASA which has not been explored before.

Mesalamine is a standard first-line therapy for managing chronic inflammatory bowel diseases, such as Crohn's disease and ulcerative colitis. Despite its established efficacy, the precise mechanism of action within enterocytes remains unclear. This study aimed to develop and validate Physiologically Based Biopharmaceutics Models (PBBM) for mesalamine (5-ASA) and its metabolite, acetyl mesalamine (Ac-5-ASA), to predict drug concentrations in plasma, colonic lumen, and colonic tissue of healthy subjects and compare the results to measured concentrations. Using the Simcyp Simulator (V22), the models accurately predicted plasma concentrations for various formulations, including intravenous, oral immediate-release and controlled release formulations within a two-fold range. Results also captured the intestinal and hepatic metabolism converting mesalamine to acetyl mesalamine. However, significant discrepancies were observed in predicting luminal and tissue concentrations, with underpredictions for Claversal and Pentasa formulations reaching factors of up to 506 and 55 for 5-ASA and Ac-5-ASA in colonic tissue, respectively. These discrepancies highlight limitations in current modeling approaches, particularly in simulating drug accumulation within enterocytes. Despite these challenges, this investigation highlights both the potential benefits and the complexities of using PBBMs. Future work should focus on generating definitive N-acetyl transferase (NAT1) abundance data with an in-vitro in-vivo extrapolation link, improving approaches to better explore local drug concentrations in the gastrointestinal tract, and addressing the gap in accurately predicting luminal and tissue concentrations in the colon.

5-Aminosalicylic acid (5-ASA), the first-line therapy for ulcerative colitis, is a poorly soluble zwitterionic drug. Unformulated 5-ASA is thought to be extensively absorbed in the small intestine.

The pH-dependent solubility of 5-ASA in vitro and the intestinal membrane distribution of 5-ASA and its N-acetyl metabolite (AC-5-ASA) after the oral administration of 5-ASA were examined in fed rats. 5-ASA was administered as a suspension in water, 0.1 M HCl, or 0.1 M NaOH to untreated rats or as a solution in 5% NaHCO3 to lansoprazole-pretreated rats.

5-ASA solubility in vitro was higher at pH < 2 and pH > 7. In rats, the 5-ASA and AC-5-ASA were detected mostly in the small intestine at 3 h and in the colonic region at 8 h after administration. The dosing vehicle (suspension or solution) and lansoprazole pretreatment did not significantly affect the pH of the luminal fluid in rats or the 5-ASA distribution in membranes.

The 5-ASA distribution in membranes in the proximal intestine was found to be restricted by the intrinsic regional luminal pH, low solubility, and saturable membrane permeability. Unabsorbed 5-ASA in the proximal intestine was delivered to the distal intestine. The higher the oral dose of 5-ASA, the more 5-ASA may be delivered to the distal intestine due to the restricted absorption in the small intestine.

Small intestinal bacterial overgrowth (SIBO) is characterized as the increase in the number and/or alteration in the type of bacteria in the upper gastrointestinal tract and accompanies various bowel symptoms such as abdominal pain, bloating, gases, diarrhea, and so on. Clinically, SIBO is diagnosed by microbial culture in duodenum/jejunum fluid aspirates and/or the breath tests (BT) of hydrogen/methane gases after ingestion of carbohydrates such as glucose. The cultural analysis of aspirates is regarded as the golden standard for the diagnosis of SIBO; however, this is invasive and is not without risk to the patients. BT is an inexpensive and safe diagnostic test but lacks diagnostic sensitivity and specificity depending on the disease states of patients. Additionally, the urinary excretion tests are used for the SIBO diagnosis using chemically synthesized bile acid conjugates such as cholic acid (CA) conjugated with para-aminobenzoic acid (PABA-CA), ursodeoxycholic acid (UDCA) conjugated with PABA (PABA-UDCA) or conjugated with 5-aminosalicylic acid (5-ASA-UDCA). These conjugates are split by bacterial bile acid (cholylglycine) hydrolase. In the tests, the time courses of the urinary excretion rates of PABA or 5-ASA, including their metabolites, are determined as the measure of hydrolytic activity of intestinal bacteria. Although the number of clinical trials with this urinary excretion tests is small, results demonstrated the usefulness of bile acid conjugates as SIBO diagnostic substrates. PABA-UDCA disulfate, a single-pass type unabsorbable compound without the hydrolysis of conjugates, was likely to offer a simple and rapid method for the evaluation of SIBO without the use of radioisotopes or expensive special apparatus. Treatments of SIBO with antibiotics, probiotics, therapeutic diets, herbal medicines, and/or fecal microbiota transplantation are also reviewed.

Although in-vivo bioequivalence (BE) study serves as a golden standard for establishing interchangeability of oral dosage forms, it remains challenging for products with high inter-subject variability such as mesalazine enteric-coated tablet to fulfil the BE criteria set by regulatory authorities. Mesalazine, as a BCS class IV drug, targets to be delivered to distal ileum or colon with a pH-sensitive polymer coating for the remission of ulcerative colitis. Through population pharmacokinetic (PK) analysis and in-vitro in-vivo correlation (IVIVC) modeling on the dissolution and BE data of a generic enteric-coated product (EM) and its reference Salofalk® 250 mg tablet (SM), we for the first time revealed the underlying mechanism of the high inter-subject variability for such delayed-release formulation. It was also noted that the in-vivo start time of absorption (T_s) for EM and SM was positively correlated with their in-vitro lag time (T_lag) under the USP three-stage dissolution condition and reversely correlated with their in-vivo bioavailability. The varied oral bioavailability of mesalazine enteric-coated tablet was mainly due to the varied N-acetyltransferase activities along GI tract. Although such extensive intestinal first-pass metabolism with large individual differences led to a significant variation of mesalazine C_max (coefficient of variation: 60-63.5%) and AUC_0-t (coefficient of variation: 37.5-46.9%), the corresponding variations in the total absorbed mesalazine (mesalazine and its metabolite N-acetyl mesalazine) were significantly reduced by 12 to 45%. Since the BE purpose for mesalazine enteric-coated tablet focused on their comparable safety profiles, total absorbed mesalazine was recommended to be adopted for the development of the IVIVC model and BE evaluation for EM. All in all, our model-based approach has not only successfully identified the key factors that affect the BE of EM to guide its further formulation optimization, but also demonstrated the indispensable role of modeling in the development of generic pharmaceutical product at its early stages.

Targeted drug delivery to the colon offers a myriad of benefits, including treatment of local diseases, direct access to unique therapeutic targets and the potential for increasing systemic drug bioavailability and efficacy. Although a range of traditional colonic delivery technologies are available, these systems exhibit inconsistent drug release due to physiological variability between and within individuals, which may be further exacerbated by underlying disease states. In recent years, significant translational and commercial advances have been made with the introduction of new technologies that incorporate independent multi-stimuli release mechanisms (pH and/or microbiota-dependent release). Harnessing these advanced technologies offers new possibilities for drug delivery via the colon, including the delivery of biopharmaceuticals, vaccines, nutrients, and microbiome therapeutics for the treatment of both local and systemic diseases. This review details the latest advances in colonic drug delivery, with an emphasis on emerging therapeutic opportunities and clinical technology translation.

In case of colon-specific delivery of therapeutic agents through oral route, microbial/enzyme-triggered release approach has several advantages over other approaches due to unique microbial ecosystem in the colon. Multiple-unit carriers have an edge over single-unit carriers for this purpose. Among different materials/polymers explored, pectin appears as a promising biopolymer to construct microbial-triggered colon-specific carriers. Pectin is specifically degraded by colonic enzymes but insusceptible to upper gastro-intestinal enzymes. In this article, utilization of pectin solely or in combination with other polymers and/or colonic-delivery approaches is critically discussed in detail in the context of multi-particulate systems. Several studies showed that pectin-based carriers can prevent the release of payload in the stomach but start to release in the intestine. Hence, pectin alone may construct delayed release formulation but may not be sufficient for effective colon-targeting. On the other hand, combination of pectin with other materials/polymers (e.g., chitosan and Eudragit® S-100) has demonstrated huge promise for colon-specific release of payload. Hence, smartly designed pectin-based multi-particulate carriers, especially in combination with other polymers and/or colon-targeting approaches (e.g., microbial-triggered + pH-triggered or microbial-triggered + pH-triggered + time-release or microbial-triggered + pH-triggered + pressure-based), can be successful colon-specific delivery systems. However, more clinical trials are necessary to bring this idea from bench to bedside.

Introduction: The peak age of diagnosis of inflammatory bowel disease (IBD) occurs during childbearing years, therefore management of IBD during pregnancy is a frequent occurrence. Maintenance of disease remission is crucial to optimize pregnancy outcomes, and potential maternal or fetal toxicity from medications must be balanced against the risks of untreated IBD.Areas covered: This review summarizes the literature on safety and use of medications for IBD during pregnancy and lactation.Expert opinion: 5-aminosalicylates, corticosteroids and thiopurines are safe for use during pregnancy, while methotrexate and tofacitinib should only be used with extreme caution. Anti-TNF agents (except certolizumab), vedolizumab, ustekinumab and tofacitinib readily traverse the placenta via active transport, therefore theoretically may affect fetal development. Certolizumab only undergoes passive transfer across the placenta, thus has markedly lower cord blood levels making it likely the safest biologic agent for infants. There is reasonable evidence to support the safety of anti-TNF monotherapy and combination therapy during pregnancy and lactation. Vedolizumab and ustekinumab are also thought to be safe in pregnancy and lactation, while tofacitinib is generally avoided due to teratogenic effects in animal studies.

Peak drug concentration (C_max ) and total exposure, such as area under the concentration-time curve (AUC) from time zero to infinity may be insufficient for assessing relative bioavailability (BA) or bioequivalence (BE) among two products in cases where rapid onset of action or controlled duration of effect is needed to ensure similar drug efficacy. Regulatory agencies have recommended the use of partial AUC (pAUC) as an additional exposure measure for relative BA or BE assessments. The pAUC metric describes pharmacokinetic profiles with the focus on quantification of exposures over specific time intervals to support the determination of relative BA or BE for these drug products in relation to respective reference products. The principles and rationales for using pAUCs are included in the US Food and Drug Administration (FDA)'s general BA or BE guidances. Specific pAUC recommendations are also reflected in product-specific guidances for generic drug development published by the FDA. Rationales for the use of pAUCs in relative BA or BE assessments are based on drug-specific and product-specific considerations. This white paper introduces the general framework, including rationales for pAUC recommendations, and provides an overview of the current status, challenges, and the FDA considerations on the use of pAUC for relative BA or BE assessments in the United States.

Although oral mesalamine is the first-choice drug for treating mild-to-moderate ulcerative colitis (UC), some patients show symptoms of intolerance, including exacerbation of diarrhea and abdominal pain. The present study clarified the current state and clinical courses of patients with mesalamine intolerance.

Patients who were diagnosed with UC and administered oral mesalamine at eight hospitals in Japan with a follow-up period exceeding 1 year were analyzed.

Sixty-seven (11%) of 633 patients showed intolerance to at least one formulation of oral mesalamine. The frequency of mesalamine intolerance has increased in recent years, rising from 5.3% in 2007-2010 to 9.1% in 2011-2013 and 16.2% in 2014-2016. The most common complications were the exacerbation of diarrhea (n = 29), a fever (n = 25), and abdominal pain (n = 22). Readministration of mesalamine/sulfasalazine was attempted in 43 patients, mostly with other types of formulation of mesalamine, and more than half of these patients proved to be tolerant. The risk factors for mesalamine intolerance were female gender (odds ratio [OR] = 1.83; 95% confidence interval [CI], 1.08-3.12), age < 60 years old (OR = 2.82; CI, 1.19-8.33), and pancolitis (OR = 2.09; 95% CI, 1.23-3.60). There were no significant differences in the use of anti-tumor necrosis factor-α agents, colectomy, or steroid-free remission at the last visit between patients with and without mesalamine intolerance.

Mesalamine intolerance is not rare, and its frequency has been increasing recently. The prognosis of patients with mesalamine intolerance did not differ significantly from that of those without intolerance.

Oral 5-aminosalicylic acid (5-ASA; also known as mesalazine or mesalamine) preparations were intended to avoid the adverse effects of sulfasalazine (SASP) while maintaining its therapeutic benefits. In an earlier version of this review, we found that 5-ASA drugs were more effective than placebo for maintenance of remission of ulcerative colitis (UC), but had a significant therapeutic inferiority relative to SASP. In this version, we have rerun the search to bring the review up to date.

To assess the efficacy, dose-responsiveness, and safety of oral 5-ASA compared to placebo, SASP, or 5-ASA comparators for maintenance of remission in quiescent UC and to compare the efficacy and safety of once-daily dosing of oral 5-ASA with conventional (two or three times daily) dosing regimens.

We performed a literature search for studies on 11 June 2019 using MEDLINE, Embase, and the Cochrane Library. In addition, we searched review articles and conference proceedings.

We included randomized controlled trials with a minimum treatment duration of six months. We considered studies of oral 5-ASA therapy for treatment of participants with quiescent UC compared with placebo, SASP, or other 5-ASA formulations. We also included studies that compared once-daily 5-ASA treatment with conventional dosing of 5-ASA and 5-ASA dose-ranging studies.

We used standard methodological procedures expected by Cochrane. The primary outcome was the failure to maintain clinical or endoscopic remission. Secondary outcomes were adherence, adverse events (AE), serious adverse events (SAE), withdrawals due to AEs, and withdrawals or exclusions after entry. Trials were separated into five comparison groups: 5-ASA versus placebo, 5-ASA versus SASP, once-daily dosing versus conventional dosing, 5-ASA (balsalazide, Pentasa, and olsalazine) versus comparator 5-ASA formulation (Asacol and Salofalk), and 5-ASA dose-ranging. We calculated the risk ratio (RR) and 95% confidence interval (CI) for each outcome. We analyzed data on an intention-to-treat basis, and used GRADE to assess the overall certainty of the evidence.

The search identified 44 studies (9967 participants). Most studies were at low risk of bias. Ten studies were at high risk of bias. Seven of these studies were single-blind and three were open-label. 5-ASA is more effective than placebo for maintenance of clinical or endoscopic remission. About 37% (335/907) of 5-ASA participants relapsed at six to 12 months compared to 55% (355/648) of placebo participants (RR 0.68, 95% CI 0.61 to 0.76; 8 studies, 1555 participants; high-certainty evidence). Adherence to study medication was not reported for this comparison. SAEs were reported in 1% (6/550) of participants in the 5-ASA group compared to 2% (5/276) of participants in the placebo group at six to 12 months (RR 0.60, 95% CI 0.19 to 1.84; 3 studies, 826 participants; low-certainty evidence). There is probably little or no difference in AEs at six to 12 months' follow-up (RR 0.93, 95% CI 0.73 to 1.18; 5 studies, 1132 participants; moderate-certainty evidence). SASP is more effective than 5-ASA for maintenance of remission. About 48% (416/871) of 5-ASA participants relapsed at six to 18 months compared to 43% (336/784) of SASP participants (RR 1.14, 95% CI 1.03 to 1.27; 12 studies, 1655 participants; high-certainty evidence). Adherence to study medication and SAEs were not reported for this comparison. There is probably little or no difference in AEs at six to 12 months' follow-up (RR 1.07, 95% CI 0.82 to 1.40; 7 studies, 1138 participants; moderate-certainty evidence). There is little or no difference in clinical or endoscopic remission rates between once-daily and conventionally dosed 5-ASA. About 37% (717/1939) of once-daily participants relapsed over 12 months compared to 39% (770/1971) of conventional-dosing participants (RR 0.94, 95% CI 0.88 to 1.01; 10 studies, 3910 participants; high-certainty evidence). There is probably little or no difference in medication adherence rates. About 10% (106/1152) of participants in the once-daily group failed to adhere to their medication regimen compared to 8% (84/1154) of participants in the conventional-dosing group (RR 1.18, 95% CI 0.72 to 1.93; 9 studies, 2306 participants; moderate-certainty evidence). About 3% (41/1587) of participants in the once-daily group experienced a SAE compared to 2% (35/1609) of participants in the conventional-dose group at six to 12 months (RR 1.20, 95% CI 0.77 to 1.87; moderate-certainty evidence). There is little or no difference in the incidence of AEs at six to 13 months' follow-up (RR 0.98, 95% CI 0.92 to 1.04; 8 studies, 3497 participants; high-certainty evidence). There may be little or no difference in the efficacy of different 5-ASA formulations. About 44% (158/358) of participants in the 5-ASA group relapsed at six to 18 months compared to 41% (142/349) of participants in the 5-ASA comparator group (RR 1.08, 95% CI 0.91 to 1.28; 6 studies, 707 participants; low-certainty evidence).

There is high-certainty evidence that 5-ASA is superior to placebo for maintenance therapy in UC. There is high-certainty evidence that 5-ASA is inferior compared to SASP. There is probably little or no difference between 5-ASA and placebo, and 5-ASA and SASP in commonly reported AEs such as flatulence, abdominal pain, nausea, diarrhea, headache, and dyspepsia. Oral 5-ASA administered once daily has a similar benefit and harm profile as conventional dosing for maintenance of remission in quiescent UC.

Oral 5-aminosalicylic acid (5-ASA) preparations were intended to avoid the adverse effects of sulfasalazine (SASP) while maintaining its therapeutic benefits. It was previously found that 5-ASA drugs in doses of at least 2 g/day were more effective than placebo but no more effective than SASP for inducing remission in ulcerative colitis (UC). This review is an update of a previously published Cochrane Review.

To assess the efficacy, dose-responsiveness and safety of oral 5-ASA compared to placebo, SASP, or 5-ASA comparators (i.e. other formulations of 5-ASA) for induction of remission in active UC. A secondary objective was to compare the efficacy and safety of once-daily dosing of oral 5-ASA versus conventional dosing regimens (two or three times daily).

We searched MEDLINE, Embase and the Cochrane Library on 11 June 2019. We also searched references, conference proceedings and study registers to identify additional studies.

We considered randomized controlled trials (RCTs) including adults (aged 18 years or more) with active UC for inclusion. We included studies that compared oral 5-ASA therapy with placebo, SASP, or other 5-ASA formulations. We also included studies that compared once-daily to conventional dosing as well as dose-ranging studies.

Outcomes include failure to induce global/clinical remission, global/clinical improvement, endoscopic remission, endoscopic improvement, adherence, adverse events (AEs), serious adverse events (SAEs), withdrawals due to AEs, and withdrawals or exclusions after entry. We analyzed five comparisons: 5-ASA versus placebo, 5-ASA versus sulfasalazine, once-daily dosing versus conventional dosing, 5-ASA (e.g. MMX mesalamine, Ipocol, Balsalazide, Pentasa, Olsalazine and 5-ASA micropellets) versus comparator 5-ASA (e.g. Asacol, Claversal, Salofalk), and 5-ASA dose-ranging. We calculated the risk ratio (RR) and 95% confidence interval (95% CI) for each outcome. We analyzed data on an intention-to-treat basis, and used GRADE to assess the overall certainty of the evidence.

We include 54 studies (9612 participants). We rated most studies at low risk of bias. Seventy-one per cent (1107/1550) of 5-ASA participants failed to enter clinical remission compared to 83% (695/837) of placebo participants (RR 0.86, 95% CI 0.82 to 0.89; 2387 participants, 11 studies; high-certainty evidence). We also observed a dose-response trend for 5-ASA. There was no difference in clinical remission rates between 5-ASA and SASP. Fifty-four per cent (150/279) of 5-ASA participants failed to enter remission compared to 58% (144/247) of SASP participants (RR 0.90, 95% CI 0.77 to 1.04; 526 participants, 8 studies; moderate-certainty evidence). There was no difference in remission rates between once-daily dosing and conventional dosing. Sixty per cent (533/881) of once-daily participants failed to enter clinical remission compared to 61% (538/880) of conventionally-dosed participants (RR 0.99, 95% CI 0.93 to 1.06; 1761 participants, 5 studies; high-certainty evidence). Eight per cent (15/179) of participants dosed once daily failed to adhere to their medication regimen compared to 6% (11/179) of conventionally-dosed participants (RR 1.36, 95% CI 0.64 to 2.86; 358 participants, 2 studies; low-certainty evidence). There does not appear to be any difference in efficacy among the various 5-ASA formulations. Fifty per cent (507/1022) of participants in the 5-ASA group failed to enter remission compared to 52% (491/946) of participants in the 5-ASA comparator group (RR 0.94, 95% CI 0.86 to 1.02; 1968 participants, 11 studies; moderate-certainty evidence). There was no evidence of a difference in the incidence of adverse events and serious adverse events between 5-ASA and placebo, once-daily and conventionally-dosed 5-ASA, and 5-ASA and comparator 5-ASA formulation studies. Common adverse events included flatulence, abdominal pain, nausea, diarrhea, headache and worsening UC. SASP was not as well tolerated as 5-ASA. Twenty-nine per cent (118/411) of SASP participants experienced an AE compared to 15% (72/498) of 5-ASA participants (RR 0.48, 95% CI 0.36 to 0.63; 909 participants, 12 studies; moderate-certainty evidence).

There is high-certainty evidence that 5-ASA is superior to placebo, and moderate-certainty evidence that 5-ASA is not more effective than SASP. Considering relative costs, a clinical advantage to using oral 5-ASA in place of SASP appears unlikely. High-certainty evidence suggests 5-ASA dosed once daily appears to be as efficacious as conventionally-dosed 5-ASA. There may be little or no difference in efficacy or safety among the various 5-ASA formulations.

After the pH dependency of novel pH-dependent ileocolonic drug delivery systems is confirmed in vitro, their performance should be evaluated in human volunteers.

Oral mesalazine and sulfasalazine (SASP) are key drugs for treating ulcerative colitis (UC). The efficacy of switching from one of the several mesalazine formulations to another is largely unknown. This study assessed the efficacy of switching among three types of mesalazine formulation and SASP for UC therapy.

UC patients receiving high-dose mesalazine/SASP who switched to other formulations due to disease activity were considered eligible. Efficacy was evaluated 2, 6, and 12 months after switching.

A total of 106 switches in 88 UC patients were analyzed. The efficacy at 2 months after switching was observed in 23/39 (59%) cases from any mesalazine formulation to SASP, in 18/55 (33%) cases from one mesalazine to another, and in 2/12 (17%) cases from SASP to any mesalazine formulation. Nine of 43 effective cases showed inefficacy or became intolerant post-switching. Delayed efficacy more than two months after switching was observed in four cases. Steroid-free remission was achieved in 42/106 (39%) cases-within 100 days in 35 of these cases (83%).

Switching from mesalazine to SASP was effective in more than half of cases. The efficacy of switching between mesalazine formulations was lower but may be worth attempting in clinical practice from a safety perspective.

Crohn's disease (CD) is a chronic inflammatory disorder that can involve any part of the gastrointestinal tract. 5-Aminosalicylates (5-ASAs) are locally acting, anti-inflammatory compounds that reduce inflammation of the colonic mucosa with release profiles that vary among various commercially available formulations. This updated Cochrane review summarizes current evidence on the use of 5-ASA formulations for maintenance of surgically-induced remission in CD.

To assess the efficacy and safety of 5-ASA agents for the maintenance of surgically-induced remission in CD.

We searched MEDLINE, Embase, CENTRAL, the Cochrane IBD Group Specialized Register from inception to 16 July 2018. We also searched references, conference abstracts, and trials registers.

Randomised controlled trials (RCTs) that included participants with CD in remission following surgery and compared 5-ASAs to no treatment, placebo or any other active intervention with duration of at least three months were considered for inclusion.

We used standard methodological procedures expected by Cochrane. The primary outcome was clinical relapse. Secondary outcomes included endoscopic recurrence, radiologic and surgical relapse, adverse events, serious adverse events and withdrawal due to adverse events.

Fourteen RCTs (1867 participants) were included in the review. Participants (15 to 70 years) were recruited from gastroenterology hospitals and medical clinics in Europe and North America and followed up between 3 and 72 months. The risk of bias was assessed as 'low' in one study, 'unclear' in seven and as 'high' in six.At 12 months, 36% (20/55) of participants in the 5-ASA group experienced clinical relapse compared to 51% (28/55) in the no treatment control group (RR 0.71, 95% CI 0.46 to 1.10; low certainty evidence). Moderate certainty evidence suggests that 5-ASAs are more effective for preventing clinical relapse than placebo. During a follow-up period of 12 to 72 months, 36% (131/361) of 5-ASA participants relapsed compared to 43% (160/369) of placebo participants (RR 0.83, 95% CI 0.72 to 0.96; I² = 0%; moderate certainty evidence). At 12 months, 17% (17/101) of the 4 g/day mesalamine group relapsed compared to 26% (27/105) of the 2.4 g/day group (RR 0.65, 95% CI 0.38 to 1.13; moderate certainty evidence). There was no evidence of a difference in clinical relapse rates when 5-ASA compounds were compared to purine antimetabolites. At 24 months, 61% (103/170) of mesalamine participants relapsed compared to 67% (119/177) of azathioprine participants (RR 0.90, 95% CI 0.76 to 1.07; I² = 28%; low certainty evidence). During 24 months, 50% (9/18) of 5-ASA participants had clinical relapse compared to 13% (2/16) of adalimumab participants (RR 4.0, 95% CI 1.01 to 15.84; low certainty evidence). The effects of sulphasalazine compared to placebo on clinical relapse rate is uncertain. After 18 to 36 months, 66% (95/143) of participants treated with sulphasalazine relapsed compared to 71% (110/155) in the placebo group (RR 0.88, 95% CI 0.56 to 1.38; I² = 38%; low certainty evidence).The effect of 5-ASA drugs on safety was uncertain. During 24 months follow-up, 4% (2/55) of 5-ASA participants experienced adverse events compared to none (0/55) in the no treatment control group (RR 5.00, 95% CI 0.25 to 101.81; very low certainty evidence). An equal proportion of 5-ASA participants (10%; 23/241) and placebo (9%; 20/225) groups experienced an adverse event during a follow-up of 3 to 72 months (RR 1.07, 95% CI 0.60 to 1.91; I² = 0%; low certainty evidence). Adverse event rates were similar in the 5-ASA and purine analogues groups. However, serious adverse events and withdrawals due to adverse events were more common in participants who received purine analogues than 5-ASA. At 52 weeks to 24 months, 52% (107/207) of 5-ASA participants had an adverse event compared to 47% (102/218) of purine analogue participants (RR 1.11, 95% CI 0.97 to 1.27, I² = 0%; low certainty evidence). Four per cent (6/152) of 5-ASA participants had a serious adverse event compared to 17% (27/159) of purine analogue participants (RR 0.30, 95% CI 0.11 to 0.80; very low certainty evidence). Eight per cent (17/207) of 5-ASA participants withdrew due to an adverse event compared to 19% (42/218) of purine analogue participants (RR 0.48, 95% CI 0.28 to 0.83; low certainty evidence). Adverse event rates were similar in high and low dose mesalamine participants. After 12 months, 2% (2/101) of 4 g/day mesalamine participants had an adverse event compared to 2% (2/105) of 2.4 g/day participants (RR 1.04, 95% CI 0.15 to 7.24; low certainty evidence). The proportion of participants who experienced adverse events over a 24 month follow-up in the mesalamine group was 78% (14/18) compared to 69% (11/16) of adalimumab participants (RR 1.13, 95% CI 0.75 to 1.71; very low certainty evidence). None (0/32) of the sulphasalazine participants had an adverse event at 18 months follow-up compared to 3% (1/34) of the placebo group (RR 0.35, 95% CI 0.01 to 8.38; very low certainty evidence). Commonly reported adverse events in the included studies were diarrhoea, nausea, increased liver function tests, pancreatitis, and abdominal pain.

5-ASA preparations are superior to placebo for the maintenance of surgically-induced clinical remission in patients with CD (moderate certainty). The number needed to treat to prevent one relapse was 13 patients. The evidence for endoscopic remission is uncertain. The sulphasalazine class of 5-ASA agents failed to demonstrate superiority against placebo, 5-ASAs failed to demonstrate superiority compared to no treatment (very low and low certainty). The efficacy of two different doses of the same 5-ASA and the efficacy of 5-ASA compared to purine antimetabolites (azathioprine or 6-mercaptopurine) in maintaining surgically-induced remission of CD remains unclear. However, purine analogues lead to more serious adverse events and discontinuation due to adverse events. There is a low certainty that 5-ASA is inferior for maintaining surgically-induced remission of CD compared to biologics (anti TNF-ɑ). 5-ASA formulations appear to be safe with no difference in the occurrence of adverse events or withdrawal when compared with placebo, no treatment or biologics.

Mesalazine is the most commonly prescribed medication for mild to moderate ulcerative colitis. It is generally well tolerated with some reported side effects.

To summarise adverse drug events to mesalazine and recommend techniques for management. Furthermore, to determine if there is a dose-dependent relationship between high (>2.4 g/day) vs low dosing (≤2.4 g/day) and occurrence of adverse drug events.

A literature search for relevant studies from inception to 1 December 2017 of the MEDLINE database was conducted. Two reviewers screened all titles identified. Data obtained from randomised controlled trials was used to estimate incidence rates of each adverse event. Two reviewers independently assessed methodological risk of bias and performed data extraction.

3581 articles were initially considered. Of these, 3573 were screened, 622 reviewed and 91 included. Adverse events attributed to mesalazine included inflammatory reactions, pancreatitis, cardiotoxicity, hepatotoxicity, musculoskeletal complaints, respiratory symptoms, nephropathies and sexual dysfunction. There does not appear to be a dose-dependent relationship of mesalazine and occurrence of adverse events.

Patients on mesalazine should be monitored for worsening of ulcerative colitis and development of new onset organ dysfunction. High-dose mesalazine appears to have similar safety profile as low dose, and is not associated with greater risk of adverse events. Prior to placing a patient on mesalazine, baseline liver and renal function should be evaluated. Renal function should be periodically assessed, whereas other testing should be performed depending on development of symptoms.

Obesity is associated with a series of metabolic complications, including dyslipidemia and insulin resistance (IR) that lack effective therapies. In recent years, intestinal inflammation has been suggested to contribute to obesity related metabolic syndrome and targeting gut inflammation with 5-ASA improves diet induced IR, however, its role in dyslipidemia is unknown and has never been explored. In the present study, we reported for the first time that administration of 5-ASA for 12 weeks significantly improved lipid profile by repressing plasma triglycerides and free cholesterol levels in mice fed high-fat cholesterol diet (HFC). In addition, liver lipids were significantly reduced by 5-ASA treatment in HFC-fed mice. Mechanistically, anti-inflammatory genes peroxisome proliferator-activated receptor-γ (Pparγ) and M2 marker, such as Mrc1 and Ym1, were remarkably upregulated, while pro-inflammation gene monocyte chemoattractant protein-1 (Mcp-1) were downregulated in small intestine of mice treated by 5-ASA. Further, 5-ASA improved gastrointestinal barrier by increasing the expression of the tight junction marker ZO-1. 5-ASA also enhanced cholesterol translocation by elevating genes expression of Npc1l1 and Abcg5/8. Moreover, mice fed HFC 5-ASA expressed increased Pparα in small intestinal and its target genes function in lipid oxidation and hydrolysis were remarkable elevated. Taken together, we reported a novel role of 5-ASA which may serve as a therapy target intestinal inflammation induced dyslipidemia.

Ulcerative colitis (UC) is a chronic inflammatory bowel disease (IBD) of the colon as a target site. Previous reports regarding the efficacy of α-mangostin (αMG) to inhibit nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinases (MAPKs) as well as relatively high distribution to the colon suggested the therapeutic potential of this compound in UC model. In dextran sodium sulfate (DSS)-induced colitis mice (DSS mice), the disease activity index scores involving diarrhea, bloody stool, body weight reduction, and myeloperoxidase (MPO) activities of the esophagus and colon increased with the reduced colon length. Also histologic disturbances and changes of NF-κB and MAPK pathways including phosphorylation of IκB kinase, ERK1/2, SAPK/JNK and p38 were observed in the colon of the DSS mice. However, all of these impaired conditions in the DSS mice were restored by αMG treatment, and the intestinal metabolism of αMG decreased, increasing its distribution to the colons in the DSS mice compared with the control mice. All of these results suggest that high distribution of αMG in the colon might attenuate DSS-induced colitis by inhibiting NF-κB and MAPK pathways in the colon.

The prevention of relapse is a major issue in the management of Crohn's disease. Corticosteroids, the mainstay of treatment of acute exacerbations, are not effective for maintenance of remission and its chronic use is limited by numerous adverse events. Randomised controlled trials assessing the efficacy of oral 5-aminosalicylic acid (5-ASA) agents for maintenance of medically-induced remission in Crohn's disease have produced conflicting results.

To conduct a systematic review to evaluate the efficacy and safety of oral 5-ASA agents for the maintenance of medically-induced remission in Crohn's disease.

We searched MEDLINE, EMBASE, CENTRAL and the IBD Group Specialized Register from inception to 8 June 2016. We also searched reference lists and conference proceedings.

We included randomised controlled trials that compared oral 5-ASA agents to either placebo or sulphasalazine in patients with quiescent Crohn's disease. The trials had to have a treatment duration of at least six months.

Two authors independently extracted data and performed the risk of bias assessment. Any disagreements were resolved by discussion and consensus. The primary outcome measure was the occurrence of relapse as defined by the primary studies. Secondary outcomes included time to relapse, adverse events, withdrawal due to adverse events and serious adverse events. We calculated the pooled risk ratio (RR) and corresponding 95% confidence interval (95% CI) using a fixed-effect model. All data were analysed on an intention-to-treat basis and drop-outs were considered to be relapses. Sensitivity analyses included an available case analysis where drop-outs were ignored and using a random-effects model. We evaluated the overall quality of the evidence supporting the outcomes using the GRADE criteria.

Twelve studies (2146 participants) that compared 5-ASA to placebo were included. We did not identify any studies that compared sulphasalazine to placebo. Seven studies were judged to be at low risk of bias. The other studies were judged to have an unclear risk of bias for various items due to insufficient details to allow for a judgement. There was no statistically significant difference in relapse rates at 12 months. Fifty-three per cent (526/998) of 5-ASA patients (dose 1.6 g to 4 g/day) relapsed at 12 months compared to 54% (544/1016) of placebo patients (RR 0.98, 95% CI 0.91 to 1.07; 11 studies; 2014 patients; moderate-quality evidence). Sensitivity analyses based on an available case analysis and a random-effects model had no impact on the results. One study found no difference in relapse rates at 24 months. Fifty-four per cent (31/57) of 5-ASA patients (dose 2 g/day) relapsed at 24 months compared to 58% (36/62) of placebo patients (RR 0.94, 95% CI 0.68 to 1.29, 119 patients; low-quality evidence). One paediatric study found no statistically significant difference in relapse rates at 12 months. Sixty-two per cent (29/47) of paediatric 5-ASA patients (dose 50 mg/kg/day) relapsed at 12 months compared to 64% (35/55) of paediatric placebo patients (RR 0.97, 95% CI 0.72 to 1.31; 102 patients; moderate-quality evidence). There was no statistically significant difference in the proportion of patients who experienced an adverse event, withdrawal due to adverse events or serious adverse events. Thirty-four per cent (307/900) of 5-ASA patients had at least one adverse event compared to 33% (301/914) of placebo patients (RR 1.05, 95% CI 0.95 to 1.17; 10 studies; 1814 patients). Fourteen per cent (127/917) of 5-ASA patients withdrew due to adverse events compared to 13% (119/916) of placebo patients (RR 1.11, 95% CI 0.88 to 1.38; 9 studies; 1833 patients). One per cent (3/293) of 5-ASA patients had a serious adverse event compared to 0.7% (2/283) of placebo patients (RR 1.43, 95% CI 0.24 to 2.83; 3 studies; 576 patients). Common adverse events reported in the studies included diarrhoea, nausea and vomiting, abdominal pain, headache and skin rash.

We found no evidence in this review to suggest that oral 5-ASA preparations are superior to placebo for the maintenance of medically-induced remission in patients with Crohn's disease. Additional randomised trials may not be justified.

Oral 5-aminosalicylic (5-ASA) preparations were intended to avoid the adverse effects of sulfasalazine (SASP) while maintaining its therapeutic benefits. Previously, it was found that 5-ASA drugs were more effective than placebo but had a statistically significant therapeutic inferiority relative to SASP. This updated review includes more recent studies and evaluates the effectiveness, dose-responsiveness, and safety of 5-ASA preparations used for maintenance of remission in quiescent ulcerative colitis.

The primary objectives were to assess the efficacy, dose-responsiveness and safety of oral 5-ASA compared to placebo, SASP, or 5-ASA comparators for maintenance of remission in quiescent ulcerative colitis. A secondary objective was to compare the efficacy and safety of once daily dosing of oral 5-ASA with conventional (two or three times daily) dosing regimens.

A literature search for relevant studies (inception to 9 July 2015) was performed using MEDLINE, EMBASE and the Cochrane Library. Review articles and conference proceedings were also searched to identify additional studies.

Studies were accepted for analysis if they were randomized controlled trials with a minimum treatment duration of six months. Studies of oral 5-ASA therapy for treatment of patients with quiescent ulcerative colitis compared with placebo, SASP or other 5-ASA formulations were considered for inclusion. Studies that compared once daily 5-ASA treatment with conventional dosing of 5-ASA and 5-ASA dose ranging studies were also considered for inclusion.

The primary outcome was the failure to maintain clinical or endoscopic remission. Secondary outcomes included adherence, adverse events, withdrawals due to adverse events, and withdrawals or exclusions after entry. Trials were separated into five comparison groups: 5-ASA versus placebo, 5-ASA versus sulfasalazine, once daily dosing versus conventional dosing, 5-ASA versus comparator 5-ASA formulation, and 5-ASA dose-ranging. Placebo-controlled trials were subgrouped by dosage. Once daily versus conventional dosing studies were subgrouped by formulation. 5-ASA-controlled trials were subgrouped by common 5-ASA comparators (e.g. Asacol and Salofalk). Dose-ranging studies were subgrouped by 5-ASA formulation. We calculated the risk ratio (RR) and 95% confidence intervals (95% CI) for each outcome. Data were analyzed on an intention-to-treat basis.

Forty-one studies (8928 patients) were included. The majority of included studies were rated as low risk of bias. Ten studies were rated at high risk of bias. Seven of these studies were single-blind and three studies were open-label. However, two open-label studies and four of the single-blind studies utilized investigator performed endoscopy as an endpoint, which may protect against bias. 5-ASA was significantly superior to placebo for maintenance of clinical or endoscopic remission. Forty-one per cent of 5-ASA patients relapsed compared to 58% of placebo patients (7 studies, 1298 patients; RR 0.69, 95% CI 0.62 to 0.77). There was a trend towards greater efficacy with higher doses of 5-ASA with a statistically significant benefit for the 1 to 1.9 g/day (RR 0.65; 95% CI 0.56 to 0.76) and the > 2 g/day subgroups (RR 0.73, 95% CI 0.60 to 0.89). SASP was significantly superior to 5-ASA for maintenance of remission. Forty-eight per cent of 5-ASA patients relapsed compared to 43% of SASP patients (12 studies, 1655 patients; RR 1.14, 95% CI 1.03 to 1.27). A GRADE analysis indicated that the overall quality of the evidence for the primary outcome for the placebo and SASP-controlled studies was high. No statistically significant differences in efficacy or adherence were found between once daily and conventionally dosed 5-ASA. Twenty-nine per cent of once daily patients relapsed over 12 months compared to 31% of conventionally dosed patients (8 studies, 3127 patients; RR 0.91, 95% CI 0.82 to 1.01). Eleven per cent of patients in the once daily group failed to adhere to their medication regimen compared to 9% of patients in the conventional dosing group (6 studies, 1462 patients; RR 1.22, 95% CI 0.91 to 1.64). There does not appear to be any difference in efficacy among the various 5-ASA formulations. Forty-four per cent of patients in the 5-ASA group relapsed compared to 41% of patients in the 5-ASA comparator group (6 studies, 707 patients; RR 1.08, 95% CI 0.91 to 1.28). A pooled analysis of two studies showed no statistically significant difference in efficacy between Balsalazide 6 g and 3 g/day. Twenty-three per cent of patients in the 6 g/day group relapsed compared to 33% of patients in the 3 g/day group (216 patients; RR 0.76; 95% CI 0.45 to 2.79). One study found Balsalazide 4 g to be superior to 2 g/day. Thirty-seven per cent of patients in the 4 g/day Balsalazide group relapsed compared to 55% of patients in the 2 g/day group (133 patients; RR 0.66; 95% CI 0.45 to 0.97). One study found a statistically significant difference between Salofalk granules 3 g and 1.5 g/day. Twenty-five per cent of patients in the Salofalk 3 g/day group relapsed compared to 39% of patients in the 1.5 g/day group (429 patients; RR 0.65; 95% CI 0.49 to 0.86). Common adverse events included flatulence, abdominal pain, nausea, diarrhea, headache, dyspepsia, and nasopharyngitis. There were no statistically significant differences in the incidence of adverse events between 5-ASA and placebo, 5-ASA and SASP, once daily and conventionally dosed 5-ASA, 5-ASA and comparator 5-ASA formulations and 5-ASA dose ranging studies. The trials that compared 5-ASA and SASP may have been biased in favour of SASP because most trials enrolled patients known to be tolerant to SASP which may have minimized SASP-related adverse events.

5-ASA was superior to placebo for maintenance therapy in ulcerative colitis. However, 5-ASA had a statistically significant therapeutic inferiority relative to SASP. Oral 5-ASA administered once daily is as effective and safe as conventional dosing for maintenance of remission in quiescent ulcerative colitis. There does not appear to be any difference in efficacy or safety between the various formulations of 5-ASA. Patients with extensive ulcerative colitis or with frequent relapses may benefit from a higher dose of maintenance therapy. High dose therapy appears to be as safe as low dose and is not associated with a higher incidence of adverse events.

Oral 5-aminosalicylic (5-ASA) preparations were intended to avoid the adverse effects of sulfasalazine (SASP) while maintaining its therapeutic benefits. Previously, it was found that 5-ASA drugs were more effective than placebo but had a statistically significant therapeutic inferiority relative to SASP. This updated review includes more recent studies and evaluates the effectiveness, dose-responsiveness, and safety of 5-ASA preparations used for maintenance of remission in quiescent ulcerative colitis.

The primary objectives were to assess the efficacy, dose-responsiveness and safety of oral 5-ASA compared to placebo, SASP, or 5-ASA comparators for maintenance of remission in quiescent ulcerative colitis. A secondary objective was to compare the efficacy and safety of once daily dosing of oral 5-ASA with conventional (two or three times daily) dosing regimens.

A literature search for relevant studies (inception to 9 July 2015) was performed using MEDLINE, EMBASE and the Cochrane Library. Review articles and conference proceedings were also searched to identify additional studies.

Studies were accepted for analysis if they were randomized controlled trials with a minimum treatment duration of six months. Studies of oral 5-ASA therapy for treatment of patients with quiescent ulcerative colitis compared with placebo, SASP or other 5-ASA formulations were considered for inclusion. Studies that compared once daily 5-ASA treatment with conventional dosing of 5-ASA and 5-ASA dose ranging studies were also considered for inclusion.

The primary outcome was the failure to maintain clinical or endoscopic remission. Secondary outcomes included adherence, adverse events, withdrawals due to adverse events, and withdrawals or exclusions after entry. Trials were separated into five comparison groups: 5-ASA versus placebo, 5-ASA versus sulfasalazine, once daily dosing versus conventional dosing, 5-ASA versus comparator 5-ASA formulation, and 5-ASA dose-ranging. Placebo-controlled trials were subgrouped by dosage. Once daily versus conventional dosing studies were subgrouped by formulation. 5-ASA-controlled trials were subgrouped by common 5-ASA comparators (e.g. Asacol and Salofalk). Dose-ranging studies were subgrouped by 5-ASA formulation. We calculated the risk ratio (RR) and 95% confidence intervals (95% CI) for each outcome. Data were analyzed on an intention-to-treat basis.

Forty-one studies (8928 patients) were included. The majority of included studies were rated as low risk of bias. Ten studies were rated at high risk of bias. Seven of these studies were single-blind and three studies were open-label. However, two open-label studies and four of the single-blind studies utilized investigator performed endoscopy as an endpoint, which may protect against bias. 5-ASA was significantly superior to placebo for maintenance of clinical or endoscopic remission. Forty-one per cent of 5-ASA patients relapsed compared to 58% of placebo patients (7 studies, 1298 patients; RR 0.69, 95% CI 0.62 to 0.77). There was a trend towards greater efficacy with higher doses of 5-ASA with a statistically significant benefit for the 1 to 1.9 g/day (RR 0.65; 95% CI 0.56 to 0.76) and the > 2 g/day subgroups (RR 0.73, 95% CI 0.60 to 0.89). SASP was significantly superior to 5-ASA for maintenance of remission. Forty-eight per cent of 5-ASA patients relapsed compared to 43% of SASP patients (12 studies, 1655 patients; RR 1.14, 95% CI 1.03 to 1.27). A GRADE analysis indicated that the overall quality of the evidence for the primary outcome for the placebo and SASP-controlled studies was high. No statistically significant differences in efficacy or adherence were found between once daily and conventionally dosed 5-ASA. Twenty-nine per cent of once daily patients relapsed over 12 months compared to 31% of conventionally dosed patients (8 studies, 3127 patients; RR 0.91, 95% CI 0.82 to 1.01). Eleven per cent of patients in the once daily group failed to adhere to their medication regimen compared to 9% of patients in the conventional dosing group (6 studies, 1462 patients; RR 1.22, 95% CI 0.91 to 1.64). There does not appear to be any difference in efficacy among the various 5-ASA formulations. Forty-four per cent of patients in the 5-ASA group relapsed compared to 41% of patients in the 5-ASA comparator group (6 studies, 707 patients; RR 1.08, 95% CI 0.91 to 1.28). A pooled analysis of two studies showed no statistically significant difference in efficacy between Balsalazide 6 g and 3 g/day. Twenty-three per cent of patients in the 6 g/day group relapsed compared to 33% of patients in the 3 g/day group (216 patients; RR 0.76; 95% CI 0.45 to 2.79). One study found Balsalazide 4 g to be superior to 2 g/day. Thirty-seven per cent of patients in the 4 g/day Balsalazide group relapsed compared to 55% of patients in the 2 g/day group (133 patients; RR 0.66; 95% CI 0.45 to 0.97). One study found a statistically significant difference between Salofalk granules 3 g and 1.5 g/day. Twenty-five per cent of patients in the Salofalk 3 g/day group relapsed compared to 39% of patients in the 1.5 g/day group (429 patients; RR 0.65; 95% CI 0.49 to 0.86). Common adverse events included flatulence, abdominal pain, nausea, diarrhea, headache, dyspepsia, and nasopharyngitis. There were no statistically significant differences in the incidence of adverse events between 5-ASA and placebo, 5-ASA and SASP, once daily and conventionally dosed 5-ASA, 5-ASA and comparator 5-ASA formulations and 5-ASA dose ranging studies. The trials that compared 5-ASA and SASP may have been biased in favour of SASP because most trials enrolled patients known to be tolerant to SASP which may have minimized SASP-related adverse events.

5-ASA was superior to placebo for maintenance therapy in ulcerative colitis. However, 5-ASA had a statistically significant therapeutic inferiority relative to SASP. Oral 5-ASA administered once daily is as effective and safe as conventional dosing for maintenance of remission in quiescent ulcerative colitis. There does not appear to be any difference in efficacy or safety between the various formulations of 5-ASA. Patients with extensive ulcerative colitis or with frequent relapses may benefit from a higher dose of maintenance therapy. High dose therapy appears to be as safe as low dose and is not associated with a higher incidence of adverse events.

Oral 5-aminosalicylic acid (5-ASA) preparations were intended to avoid the adverse effects of sulfasalazine (SASP) while maintaining its therapeutic benefits. Previously, it was found that 5-ASA drugs in doses of at least 2 g/day, were more effective than placebo but no more effective than SASP for inducing remission in ulcerative colitis. This updated review includes more recent studies and evaluates the efficacy and safety of 5-ASA preparations used for the treatment of mild to moderately active ulcerative colitis.

The primary objectives were to assess the efficacy, dose-responsiveness and safety of oral 5-ASA compared to placebo, SASP, or 5-ASA comparators for induction of remission in active ulcerative colitis. A secondary objective of this systematic review was to compare the efficacy and safety of once daily dosing of oral 5-ASA with conventional (two or three times daily) dosing regimens.

A computer-assisted literature search for relevant studies (inception to July 9, 2015) was performed using MEDLINE, EMBASE and the Cochrane Library. Review articles and conference proceedings were also searched to identify additional studies.

Studies were accepted for analysis if they were randomized controlled clinical trials of parallel design, with a minimum treatment duration of four weeks. Studies of oral 5-ASA therapy for treatment of patients with active ulcerative colitis compared with placebo, SASP or other formulations of 5-ASA were considered for inclusion. Studies that compared once daily 5-ASA treatment with conventional dosing of 5-ASA (two or three times daily) and 5-ASA dose ranging studies were also considered for inclusion.

The outcomes of interest were the failure to induce global/clinical remission, global/clinical improvement, endoscopic remission, endoscopic improvement, adherence, adverse events, withdrawals due to adverse events, and withdrawals or exclusions after entry. Trials were separated into five comparison groups: 5-ASA versus placebo, 5-ASA versus sulfasalazine, once daily dosing versus conventional dosing, 5-ASA versus comparator 5-ASA, and 5-ASA dose-ranging. Placebo-controlled trials were subgrouped by dosage. SASP-controlled trials were subgrouped by 5-ASA/SASP mass ratios. Once daily versus conventional dosing studies were subgrouped by formulation. 5-ASA-controlled trials were subgrouped by common 5-ASA comparators (e.g. Asacol, Claversal, Salofalk and Pentasa). Dose-ranging studies were subgrouped by 5-ASA formulation. We calculated the relative risk (RR) and 95% confidence intervals (95% CI) for each outcome. Data were analyzed on an intention-to-treat basis.

Fifty-three studies (8548 patients) were included. The majority of included studies were rated as low risk of bias. 5-ASA was significantly superior to placebo with regard to all measured outcome variables. Seventy-one per cent of 5-ASA patients failed to enter clinical remission compared to 83% of placebo patients (RR 0.86, 95% CI 0.82 to 0.89). A dose-response trend for 5-ASA was also observed. No statistically significant differences in efficacy were found between 5-ASA and SASP. Fifty-four per cent of 5-ASA patients failed to enter remission compared to 58% of SASP patients (RR 0.90, 95% CI 0.77 to 1.04). No statistically significant differences in efficacy or adherence were found between once daily and conventionally dosed 5-ASA. Forty-five per cent of once daily patients failed to enter clinical remission compared to 48% of conventionally dosed patients (RR 0.94, 95% CI 0.83 to 1.07). Eight per cent of patients dosed once daily failed to adhere to their medication regimen compared to 6% of conventionally dosed patients (RR 1.36, 95% CI 0.64 to 2.86). There does not appear to be any difference in efficacy among the various 5-ASA formulations. Fifty per cent of patients in the 5-ASA group failed to enter remission compared to 52% of patients in the 5-ASA comparator group (RR 0.94, 95% CI 0.86 to 1.02). A pooled analysis of 3 studies (n = 1459 patients) studies found no statistically significant difference in clinical improvement between Asacol 4.8 g/day and 2.4 g/day used for the treatment of moderately active ulcerative colitis. Thirty-seven per cent of patients in the 4.8 g/day group failed to improve clinically compared to 41% of patients in the 2.4 g/day group (RR 0.89; 95% CI 0.78 to 1.01). Subgroup analysis indicated that patients with moderate disease may benefit from the higher dose of 4.8 g/day. One study compared (n = 123 patients) Pentasa 4 g/day to 2.25 g/day in patients with moderate disease. Twenty-five per cent of patients in the 4 g/day group failed to improve clinically compared to 57% of patients in the 2.25 g/day group (RR 0.44; 95% CI 0.27 to 0.71). A pooled analysis of two studies comparing MMX mesalamine 4.8 g/day to 2.4 g/day found no statistically significant difference in efficacy (RR 1.03, 95% CI 0.82 to 1.29). There were no statistically significant differences in the incidence of adverse events between 5-ASA and placebo, once daily and conventionally dosed 5-ASA, 5-ASA and comparator 5-ASA formulation and 5-ASA dose ranging (high dose versus low dose) studies. Common adverse events included flatulence, abdominal pain, nausea, diarrhea, headache and worsening ulcerative colitis. SASP was not as well tolerated as 5-ASA. Twenty-nine percent of SASP patients experienced an adverse event compared to 15% of 5-ASA patients (RR 0.48, 95% CI 0.37 to 0.63).

5-ASA was superior to placebo and no more effective than SASP. Considering their relative costs, a clinical advantage to using oral 5-ASA in place of SASP appears unlikely. 5-ASA dosed once daily appears to be as efficacious and safe as conventionally dosed 5-ASA. Adherence does not appear to be enhanced by once daily dosing in the clinical trial setting. It is unknown if once daily dosing of 5-ASA improves adherence in a community-based setting. There do not appear to be any differences in efficacy or safety among the various 5-ASA formulations. A daily dosage of 2.4 g appears to be a safe and effective induction therapy for patients with mild to moderately active ulcerative colitis. Patients with moderate disease may benefit from an initial dose of 4.8 g/day.

Ulcerative colitis (UC) and Crohn's disease (CD) are diseases affecting the gastrointestinal tract. Treatment depends on the severity of the disease, site of inflammation, and patient's response. The aim of this study was to develop a zero-order sustained-release tablet containing both the anti-inflammatory drugs mesalazine and budesonide as a new treatment option for ileo-colonic CD and UC. Tablets were attained by wet granulation with hydroxypropyl methylcellulose and direct compression. Our newly developed tablet core was coated with different ColoPulse® coating thicknesses and the mesalazine and budesonide release profiles were investigated in a 600-min gastrointestinal simulation system (GISS) experiment, together with commercially available MMX®-mesalazine and MMX®-budesonide. Lag-time, release rate (k0), completeness of release, and zero-order correlation coefficient (R(2)0) could be manipulated by varying ColoPulse® coating thickness. Our newly developed combination preparation (C[4.92]) complied with all conducted European Pharmacopoeia tests as well as an accelerated 6-month stability test and had a lag-time of 250min (simulated ileum targeted), a linear release profile (mesalazine R(2)0=0.9002; budesonide R(2)0=0.9481), and drug release of 100% mesalazine and 77% budesonide. Like C[4.92], MMX®-mesalazine had a linear (R(2)0=0.9883) and complete release profile (96%). However, C[4.92] lag-time was longer (250 vs. 210min), assuring simulated ileum specificity. Remarkably, MMX®-budesonide lag-time was 480min and release was only 7% with a linear character (R(2)0=0.9906). The in vitro results suggest that MMX®-budesonide effectiveness may be improved if budesonide release in the aqueous phase would be increased and that C[4.92] is a potential, new treatment option for ileo-colonic CD and UC.

This study aimed to compare the efficacy and safety of two mesalazine formulations in the treatment of Chinese patients with ulcerative colitis (UC) in the remission phase.

In this multicenter, single-blind, randomized controlled study conducted from November 2010 to August 2012, 251 patients with UC from 18 hospitals were enrolled. The patients were randomized to treatment with mesalazine modified-release tablets (MR group, n = 126) or other enteric-coated tablets (EC group, n = 125), at 800 mg three-times daily for 48 weeks. The primary efficacy parameter was the rate of non-emergence of bloody stool. If the lower limit of the 95% confidence interval (CI) of the primary efficacy measure was over -10%, the modified-release tablets were considered non-inferior to the enteric-coated tablets. The secondary efficacy parameters included the period of non-emergence of bloody stool and the period of non-recurrence of UC. The incidences of adverse events and adverse drug reactions were compared between the two groups.

At 48 weeks of maintenance treatment, the rates of non-emergence of bloody stool were 82.99% (95% CI 73.53-92.45%) and 73.30% (95% CI 64.04-82.56%) in the MR and EC groups, respectively, and the difference between the two groups was 9.69% (95% CI -1.15-20.53%). There was no significant difference in the period of non-emergence of bloody stool and the period of non-recurrence of UC between the two groups (P > 0.05). The incidences of adverse events were 48.78% (60/123) and 48.00% (60/125) in the MR and EC groups, respectively (P = 0.902). The incidences of adverse drug reactions were 16.26% (20/123) and 13.60% (17/125) in the MR and EC groups, respectively (P = 0.556).

Mesalazine modified-release tablets were non-inferior to the enteric-coated tablets and may be considered an effective and safe treatment alternative for the maintenance of remission in Chinese patients with UC.

ClinicalTrials.gov identifier: NCT01257399.

Tillotts Pharma AG.

This study compared the efficacy and safety of two mesalazine formulations in the treatment of Chinese patients with mildly to moderately active ulcerative colitis (UC).

In this multicenter, single-blind, randomized controlled study of 251 patients with active UC conducted from November 2010 to January 2012, subjects were randomized to treatment with mesalazine modified-release tablets (MR group, n = 123) or enteric-coated tablets (EC group, n = 128) at 800 mg three-times daily for 8 weeks. The primary efficacy measure was the decrease in UC Disease Activity Index (UCDAI) at final evaluation. If the 95% confidence interval (CI) lower limit of the difference of the decrease in UCDAI between groups was over -1.0, mesalazine modified-release tablets were considered non-inferior to mesalazine enteric-coated tablets. The change in UCDAI in patients with mild and moderate (UCDAI 3-5 and 6-8 at enrollment, respectively) UC was analyzed. Secondary efficacy measures were remission and efficacy rates. Incidences of adverse drug reactions (ADRs) were calculated.

The decreases in UCDAI at final evaluation were 2.84 and 2.56 in the MR and EC groups, respectively, with a difference of 0.27 between groups (95% CI -0.34, 0.88). The remission rates were 48.33% (58/120) and 55.65% (69/124), and the efficacy rates were 63.33% (76/120) and 66.94% (83/124) in the MR and EC groups, respectively (all P > 0.05). In patients with mild UC, the decreases in UCDAI were 2.16 and 2.05 in the MR and EC groups, respectively, while in patients with moderate UC they were 3.49 and 3.03, respectively (all P > 0.05). The incidences of ADRs in the MR and EC groups were 6.61% (8/121) and 10.24% (13/127), respectively (P > 0.05). No serious ADRs were reported during the study.

Mesalazine modified-release tablets are non-inferior to enteric-coated tablets and are an effective and safe treatment option in Chinese patients with mildly to moderately active UC.

ClinicalTrials.gov identifier: NCT01257386.

Tillotts Pharma AG.

Postprandial administration of solid oral dosage forms greatly changes the dissolution environment compared to fasted state administration. The aims of this study were to investigate and forecast the effect of co-administration of a meal on drug release for delayed and/or extended release mesalamine formulations as well as design of in vitro tests to distinguish among formulations in a biorelevant way.

Five different mesalamine formulations (Asacol® 400 mg, Mezavant® 1200 mg, Pentasa® 500 mg and Salofalk® in the 250 mg and 500 mg strengths) were investigated with biorelevant dissolution methods using the USP apparatus III and USP apparatus IV (open loop mode) under both fasted and fed state conditions, as well as with the dissolution methods described in pharmacopeia for delayed and extended release mesalamine products.

Using the biorelevant experimental conditions proposed in this study, changes in release in the proximal gut due to meal intake are forecast to be minimal for Asacol®, Mezavant®, Pentasa® and Salofalk® 500 mg, while for Salofalk® 250 mg release was predicted to occur much earlier under fed state conditions. The USP apparatus III generally tended to result in faster dissolution rates and forecast more pronounced food effects for Salofalk® 250 mg than the USP apparatus IV. The biorelevant dissolution gradients were also able to reflect the in vivo behavior of the formulations.

In vitro biorelevant models can be useful in the comparison of the release behavior from different delayed and extended release mesalamine formulations as well as forecasting effects of concomitant meal intake on drug release.

The following review is a compilation of the recent advances and knowledge on the behaviour of the most frequently used compounds to treat inflammatory bowel disease in an organism.

It considers clinical aspects of each entity and the pharmacokinetic/pharmacodynamic relationship supported by the use of plasma monitoring, tissue concentrations, and certain aspects derived from pharmacogenetics.

We systematically reviewed and compared the efficacy and safety of oral mesalamine formulations (sustained release, delayed release, and prodrugs) used for induction and maintenance of remission in ulcerative colitis. The main objective of this review was to determine if there are any differences in efficacy or safety among the oral 5-ASA drugs.

A literature search in February 2013 identified all applicable randomized trials. Study quality was evaluated using the Cochrane risk of bias tool. The Grading of Recommendations Assessment, Development and Evaluation criteria were used to assess the overall quality of the evidence. Studies were subgrouped by common mesalamine comparators for meta-analysis. Studies were pooled for analysis if they compared equimolar doses of oral 5-ASA.

Seventeen studies that evaluated 2925 patients were identified. The risk of bias was low for most factors, although 1 study was single blind and 3 were open label. No difference was observed between oral 5-ASA and comparator 5-ASA formulations in the proportion of patients with clinical remission (relative risk, 0.94; 95% confidence interval, 0.86-1.02), clinical improvement (relative risk, 0.89; 95% confidence interval, 0.77-1.01), or relapse at 12 months (relative risk, 1.01; 95% confidence interval, 0.80-1.28). Subgroup analyses showed no important differences in efficacy. No significant difference was demonstrated in rates of adverse events or withdrawal due to adverse events.

There does not seem to be any difference in efficacy or safety among the various formulations of oral 5-ASA. Oral mesalamine is an effective and safe treatment of mild-to-moderate or quiescent ulcerative colitis regardless of the chosen formulation.

Mesalamine non-adherence is common among patients with ulcerative colitis (UC), and can be difficult to identify in practice. We sought to determine whether a random urine test for salicylates could be used as a marker of 5-aminosalicylic acid (5-ASA) ingestion and identify patients at risk of non-adherence. Our aim is to determine whether measurement of salicylates in a random urine sample correlates with 5-ASA levels, and predicts an individual's risk of mesalamine non-adherence.

Prospective observational study. Urinary salicylates (by colorimetry) and 5-ASA (by liquid chromatography and tandem-mass spectrometry) were measured in a random urine sample at baseline in patients and controls. Mesalamine adherence was quantified by patient self-reports at enrollment and pharmacy refills of mesalamine over 6 months.

A total of 93 patients with UC taking mesalamine maintenance therapy were prospectively enrolled from the clinic. Random urine salicylate levels (by colorimetry) were highly correlated with urine 5-ASA metabolite levels (by mass spectrometry; R2=0.9). A random urine salicylate level above 15 mg/dl distinguished patients who had recently taken mesalamine from controls (area under the curve value 0.9, sensitivity 95%, specificity 77%). A significant proportion of patients (27%) who self-identified as "high adherers" by an adherence questionnaire (Morisky Medication Adherence Scale-8) had random levels of urine salicylate below this threshold. These patients were at higher risk of objectively measured non-adherence to mesalamine over the subsequent 6 months (RR: 2.7, 95% CI: 1.1-7.0).

A random urine salicylate level measured in the clinic can identify patients who have not recently taken mesalamine, and who are at higher risk of longitudinal non-adherence. This test could be used to screen patients who may warrant interventions to improve adherence and prevent disease relapse.

Oral 5-aminosalicylic (5-ASA) preparations were intended to avoid the adverse effects of sulfasalazine (SASP) while maintaining its therapeutic benefits. Previously, it was found that 5-ASA drugs were more effective than placebo but had a statistically significant therapeutic inferiority relative to SASP. This updated review includes more recent studies and evaluates the effectiveness, dose-responsiveness, and safety of 5-ASA preparations used for maintenance of remission in quiescent ulcerative colitis.

The primary objectives were to assess the efficacy, dose-responsiveness and safety of oral 5-ASA compared to placebo, SASP, or 5-ASA comparators for maintenance of remission in quiescent ulcerative colitis. A secondary objective was to compare the efficacy and safety of once daily dosing of oral 5-ASA with conventional (two or three times daily) dosing regimens.

A literature search for relevant studies (inception to January 20, 2012) was performed using MEDLINE, EMBASE and the Cochrane Library. Review articles and conference proceedings were also searched to identify additional studies.

Studies were accepted for analysis if they were randomized controlled trials with a minimum treatment duration of six months. Studies of oral 5-ASA therapy for treatment of patients with quiescent ulcerative colitis compared with placebo, SASP or other 5-ASA formulations were considered for inclusion. Studies that compared once daily 5-ASA treatment with conventional dosing of 5-ASA and 5-ASA dose ranging studies were also considered for inclusion.

The primary outcome was the failure to maintain clinical or endoscopic remission. Secondary outcomes included adherence, adverse events, withdrawals due to adverse events, and withdrawals or exclusions after entry. Trials were separated into five comparison groups: 5-ASA versus placebo, 5-ASA versus sulfasalazine, once daily dosing versus conventional dosing, 5-ASA versus comparator 5-ASA formulation, and 5-ASA dose-ranging. Placebo-controlled trials were subgrouped by dosage. Once daily versus conventional dosing studies were subgrouped by formulation. 5-ASA-controlled trials were subgrouped by common 5-ASA comparators (e.g. Asacol and Salofalk). Dose-ranging studies were subgrouped by 5-ASA formulation. We calculated the relative risk (RR) and 95% confidence intervals (95% CI) for each outcome. Data were analyzed on an intention to treat basis.

Thirty-eight studies (8127 patients) were included. The majority of included studies were rated as low risk of bias. Eight studies were rated at high risk of bias. Six of these studies were single-blind and two studies were open-label. However, the two open-label studies and four of the single-blind studies utilized investigator performed endoscopy as an endpoint, which may protect against bias. 5-ASA was significantly superior to placebo for maintenance of clinical or endoscopic remission. Forty-one per cent of 5-ASA patients relapsed compared to 58% of placebo patients (7 studies, 1298 patients; RR 0.69, 95% CI 0.62 to 0.77). There was a trend towards greater efficacy with higher doses of 5-ASA with a statistically significant benefit for the 1 to 1.9 g/day (RR 0.65; 95% CI 0.56 to 0.76) and the > 2 g/day subgroups (RR 0.73, 95% CI 0.60 to 0.89). SASP was significantly superior to 5-ASA for maintenance of remission. Forty-eight per cent of 5-ASA patients relapsed compared to 43% of SASP patients (12 studies, 1655 patients; RR 1.14, 95% CI 1.03 to 1.27). A GRADE analysis indicated that the overall quality of the evidence for the primary outcome for the placebo and SASP-controlled studies was high. No statistically significant differences in efficacy or adherence were found between once daily and conventionally dosed 5-ASA. Twenty-nine per cent of once daily patients relapsed over 12 months compared to 31% of conventionally dosed patients (7 studies, 2826 patients; RR 0.92, 95% CI 0.83 to 1.03). Fourteen per cent of patients in the once daily group failed to adhere to their medication regimen compared to 11% of patients in the conventional dosing group (5 studies, 1161 patients; RR 1.21, 95% CI 0.90 to 1.63). There does not appear to be any difference in efficacy among the various 5-ASA formulations. Thirty-eight per cent of patients in the 5-ASA group relapsed compared to 37% of patients in the 5-ASA comparator group (5 studies, 457 patients; RR 1.01, 95% CI 0.80 to 1.28). A pooled analysis of two studies showed no statistically significant difference in efficacy between Balsalazide 6 g and 3 g/day. Twenty-three per cent of patients in the 6 g/day group relapsed compared to 33% of patients in the 3 g/day group (216 patients; RR 0.72; 95% CI 0.46 to 1.13). One study found Balsalazide 4 g to be superior to 2 g/day. Thirty-seven per cent of patients in the 4 g/day Balsalazide group relapsed compared to 55% of patients in the 2 g/day group (133 patients; RR 0.66; 95% CI 0.45 to 0.97). One study found a statistically significant difference between Salofalk granules 3 g and 1.5 g/day. Twenty-five per cent of patients in the Salofalk 3 g/day group relapsed compared to 39% of patients in the 1.5 g/day group (429 patients; RR 0.65; 95% CI 0.49 to 0.86). Common adverse events included flatulence, abdominal pain, nausea, diarrhea, headache, dyspepsia, and nasopharyngitis. There were no statistically significant differences in the incidence of adverse events between 5-ASA and placebo, 5-ASA and SASP, once daily and conventionally dosed 5-ASA, 5-ASA and comparator 5-ASA formulations and 5-ASA dose ranging studies. The trials that compared 5-ASA and SASP may have been biased in favour of SASP because most trials enrolled patients known to be tolerant to SASP which may have minimized SASP-related adverse events.

5-ASA was superior to placebo for maintenance therapy in ulcerative colitis. However, 5-ASA had a statistically significant therapeutic inferiority relative to SASP. Oral 5-ASA administered once daily is as effective and safe as conventional dosing for maintenance of remission in quiescent ulcerative colitis. There does not appear to be any difference in efficacy or safety between the various formulations of 5-ASA. Patients with extensive ulcerative colitis or with frequent relapses may benefit from a higher dose of maintenance therapy. High dose therapy appears to be as safe as low dose and is not associated with a higher incidence of adverse events.

Oral 5-aminosalicylic acid (5-ASA) preparations were intended to avoid the adverse effects of sulfasalazine (SASP) while maintaining its therapeutic benefits. Previously, it was found that 5-ASA drugs in doses of at least 2 g/day, were more effective than placebo but no more effective than SASP for inducing remission in ulcerative colitis. This updated review includes more recent studies and evaluates the efficacy and safety of 5-ASA preparations used for the treatment of mild to moderately active ulcerative colitis.

The primary objectives were to assess the efficacy, dose-responsiveness and safety of oral 5-ASA compared to placebo, SASP, or 5-ASA comparators for induction of remission in active ulcerative colitis. A secondary objective of this systematic review was to compare the efficacy and safety of once daily dosing of oral 5-ASA with conventional (two or three times daily) dosing regimens.

A computer-assisted literature search for relevant studies (inception to January 20, 2012) was performed using MEDLINE, EMBASE and the Cochrane Library. Review articles and conference proceedings were also searched to identify additional studies.

Studies were accepted for analysis if they were randomized controlled clinical trials of parallel design, with a minimum treatment duration of four weeks. Studies of oral 5-ASA therapy for treatment of patients with active ulcerative colitis compared with placebo, SASP or other formulations of 5-ASA were considered for inclusion. Studies that compared once daily 5-ASA treatment with conventional dosing of 5-ASA (two or three times daily) and 5-ASA dose ranging studies were also considered for inclusion.

The outcomes of interest were the failure to induce global/clinical remission, global/clinical improvement, endoscopic remission, endoscopic improvement, adherence, adverse events, withdrawals due to adverse events, and withdrawals or exclusions after entry. Trials were separated into five comparison groups: 5-ASA versus placebo, 5-ASA versus sulfasalazine, once daily dosing versus conventional dosing, 5-ASA versus comparator 5-ASA, and 5-ASA dose-ranging. Placebo-controlled trials were subgrouped by dosage. SASP-controlled trials were subgrouped by 5-ASA/SASP mass ratios. Once daily versus conventional dosing studies were subgrouped by formulation. 5-ASA-controlled trials were subgrouped by common 5-ASA comparators (e.g. Asacol, Claversal, Salofalk and Pentasa). Dose-ranging studies were subgrouped by 5-ASA formulation. We calculated the relative risk (RR) and 95% confidence intervals (95% CI) for each outcome. Data were analyzed on an intention to treat basis.

Forty-eight studies (7776 patients) were included. The majority of included studies were rated as low risk of bias. 5-ASA was significantly superior to placebo with regard to all measured outcome variables. Seventy-two per cent of 5-ASA patients failed to enter clinical remission compared to 85% of placebo patients (RR 0.86, 95% CI 0.81 to 0.91). A dose-response trend for 5-ASA was also observed. No statistically significant differences in efficacy were found between 5-ASA and SASP. Fifty-four per cent of 5-ASA patients failed to enter remission compared to 58% of SASP patients (RR 0.90, 95% CI 0.77 to 1.04). No statistically significant differences in efficacy or adherence were found between once daily and conventionally dosed 5-ASA. Forty-two per cent of once daily patients failed to enter clinical remission compared to 44% of conventionally dosed patients (RR 0.95, 95% CI 0.82 to 1.10). Eight per cent of patients dosed once daily failed to adhere to their medication regimen compared to 6% of conventionally dosed patients (RR 1.36, 95% CI 0.64 to 2.86). There does not appear to be any difference in efficacy among the various 5-ASA formulations. Forty-eight per cent of patients in the 5-ASA group failed to enter remission compared to 50% of patients in the 5-ASA comparator group (RR 0.94, 95% CI 0.86 to 1.03). A pooled analysis of the ASCEND (I, II and III, n = 1459 patients) studies found no statistically significant difference in clinical improvement between Asacol 4.8 g/day and 2.4 g/day used for the treatment of moderately active ulcerative colitis. Thirty-seven per cent of patients in the 4.8 g/day group failed to improve clinically compared to 41% of patients in the 2.4 g/day group (RR 0.89; 95% CI 0.78 to 1.01). Subgroup analysis indicated that patients with moderate disease may benefit from the higher dose of 4.8 g/day. One study compared (n = 123 patients) Pentasa 4 g/day to 2.25 g/day in patients with moderate disease. Twenty-five per cent of patients in the 4 g/day group failed to improve clinically compared to 57% of patients in the 2.25 g/day group (RR 0.44; 95% CI 0.27 to 0.71). A pooled analysis of two studies comparing MMX mesalamine 4.8 g/day to 2.4 g/day found no statistically significant difference in efficacy (RR 1.03, 95% CI 0.82 to 1.29). 5-ASA was generally safe and common adverse events included flatulence, abdominal pain, nausea, diarrhea, headache and worsening ulcerative colitis. There were no statistically significant differences in the incidence of adverse events between 5-ASA and placebo, once daily and conventionally dosed 5-ASA, 5-ASA and comparator 5-ASA formulation and 5-ASA dose ranging (high dose versus low dose) studies. SASP was not as well tolerated as 5-ASA. Twenty-nine percent of SASP patients experienced an adverse event compared to 15% of 5-ASA patients (RR 0.48, 95% CI 0.37 to 0.63).

5-ASA was superior to placebo and no more effective than SASP. Considering their relative costs, a clinical advantage to using oral 5-ASA in place of SASP appears unlikely. 5-ASA dosed once daily appears to be as efficacious and safe as conventionally dosed 5-ASA. Adherence does not appear to be enhanced by once daily dosing in the clinical trial setting. It is unknown if once daily dosing of 5-ASA improves adherence in a community-based setting. There do not appear to be any differences in efficacy or safety among the various 5-ASA formulations. A daily dosage of 2.4 g appears to be a safe and effective induction therapy for patients with mild to moderately active ulcerative colitis. Patients with moderate disease may benefit from an initial dose of 4.8 g/day.

COX-2 (cyclo-oxygenase-2) and PGE₂ (prostaglandin E₂) play a key role in sustaining CRC (colorectal cancer) cell growth and survival. Indeed, the use of agents targeting the COX-2/PGE₂ axis has been associated with a reduction in the development of CRC in both humans and murine models of colon carcinogenesis. In the present study, we investigated whether 2-methoxy-5-amino-N-hydroxybenzamide (herein termed 2-14), a derivative of mesalamine that inhibits CRC cell growth both in vitro and in vivo, negatively regulates COX-2/PGE₂ expression in CRC cells and assessed whether the 2-14-mediated anti-neoplastic effect is strictly dependent on the inhibition of this pathway. Our results show that 2-14 blocks the growth and enhances the death of HT-115, a CRC cell line overexpressing COX-2, and that these effects associate with inhibition of COX-2 but not COX-1. 2-14 also down-regulates TNFα (tumour necrosis factor α)-induced COX-2 in HT-29 cells as well as COX-2/PGE₂ expression in ex vivo cultures of human CRC explants. Similarly, 2-14 reduces COX-2, but not COX-1, in tumoural areas developing in a mouse model of CAC (colitis-associated colon cancer). Finally, we show that 2-14 exhibits in vitro and in vivo anti-mitogenic effects in DLD-1, a COX-deficient CRC cell line. Taken together, these results suggest that 2-14 inhibits CRC cell growth through COX-2-dependent and -independent mechanisms.

Mesalamine has been used as the first-line medication for the treatment of ulcerative colitis (UC). We directly compared the efficacy and safety of two different mesalamine formulations in the maintenance of remission in patients with UC.

In a multicenter, double-blind, randomized study, 131 patients with quiescent UC were assigned to two groups: 65 to receive a pH-dependent release formulation of mesalamine at 2.4 g/day (pH-2.4 g) and 66 to receive a time-dependent release formulation of mesalamine at 2.25 g/day (Time-2.25 g). Both formulations were administered three times daily for 48 weeks. The primary endpoint was the proportion of patients without bloody stools.

In the full analysis set (n = 130), the proportion of patients without bloody stools was 76.9% in the pH-2.4 g and 69.2% in the Time-2.25 g, demonstrating the noninferiority of pH-2.4 g to Time-2.25 g. No statistically significant difference in time to bloody stools was found between the two formulations (P = 0.27, log-rank test), but the time to bloody stools tended to be longer in pH-2.4 g compared to Time-2.25 g, and a similar trend was observed with regard to the time to relapse. No differences were observed between the safety profiles of the two formulations.

The pH- and time-dependent release of mesalamine formulations were similarly safe and effective. Interestingly, the remission phase tended to be longer in the group that received the pH-dependent formulation compared to the group that received the time-dependent formulation (UMIN Clinical Trials Registry, no. C000000289).

Mesalamine is the first-line drug for the treatment of ulcerative colitis (UC). We directly compared the efficacy and safety of two mesalamine formulations for the induction of remission in patients with UC.

In a multicenter, double-blind, randomized study, 229 patients with mild-to-moderate active UC were assigned to 4 groups: 66 and 65 received a pH-dependent release formulation of 2.4 g/day (pH-2.4 g) or 3.6 g/day (pH-3.6 g), respectively; 65 received a time-dependent release formulation of 2.25 g/day (Time-2.25 g), and 33 received placebo (Placebo). The drugs were administered three times daily for eight weeks. The primary endpoint was a decrease in the UC disease activity index (UC-DAI).

In the full analysis set (n = 225) the decrease in UC-DAI in each group was 1.5 in pH-2.4 g, 2.9 in pH-3.6 g, 1.3 in Time-2.25 g and 0.3 in Placebo, respectively. These results demonstrate the superiority of pH-3.6 g over Time-2.25 g (P = 0.003) and the noninferiority of pH-2.4 g to Time-2.25 g. Among the patients with proctitis-type UC, a significant decrease in UC-DAI was observed in pH-2.4 g and pH-3.6 g as compared to Placebo, but not in Time-2.25 g. No differences were observed in the safety profiles.

Higher dose of the pH-dependent release formulation was more effective for induction of remission in patients with mild-to-moderate active UC. Additionally, the pH-dependent release formulation was preferable to the time-dependent release formulation for patients with proctitis-type UC (UMIN Clinical Trials Registry, no. C000000288).

The practice of dosing mesalamines in divided doses for the treatment of ulcerative colitis (UC) began with sulfasalazine and was driven by sulfapyridine toxicity. This convention and the assumption that dosing multiple times a day is necessary to treat UC had not been challenged until recently. This study was conducted to determine the efficacy and safety of once-daily dosing of delayed-release mesalamine (Asacol 400-mg tablets) compared with twice-daily dosing for maintaining remission in UC patients.

A multicenter, randomized, investigator-blinded, 12-month, active-control trial was conducted to assess the noninferiority of delayed-release mesalamine 1.6-2.4 g/day administered once daily compared with twice daily in patients with mild-to-moderate UC currently in clinical remission. The primary end point was maintenance of clinical remission at month 6.

A total of 1023 patients were randomized and dosed. The primary objective of noninferiority was met. At month 6, 90.5% of patients receiving once-daily dosing had maintained clinical remission, compared with 91.8% of patients receiving twice-daily dosing (95% confidence interval for twice daily - once daily, -2.3 to 4.9). At month 12, 85.4% of patients receiving once-daily dosing had maintained clinical remission, compared with 85.4% of patients receiving twice-daily dosing (95% confidence interval for twice daily - once daily, -4.6 to 4.7). Both regimens had low rates of withdrawals as a result of adverse events and serious adverse events.

Once-daily dosing of delayed-release mesalamine at doses of 1.6-2.4 g/day was shown to be as effective as twice-daily dosing for maintenance of clinical remission in patients with UC.

Mesalamine has been reported to protect against inflammatory bowel disease-related colorectal cancer (CRC), but several drug-related issues have limited its use in chemopreventive programs. We evaluated the antineoplastic properties of mesalamine derivatives using in vitro and in vivo models of CRC.

CRC cell proliferation and cell-cycle progression were evaluated by flow cytometry after exposure to mesalamine or mesalamine derivatives. Cyclins, cyclin-dependent kinases, and endoplasmic reticulum stress-related molecules were examined by immunoblotting. The in vivo antineoplastic effect of 2-methoxy-5-amino-N-hydroxybenzamide (2-14) was evaluated in a syngenic, CT26-derived xenograft mouse model of CRC and in the azoxymethane/dextran sulfate sodium-induced mouse model of colitis-associated CRC.

The mesalamine derivative 2-14 was 10-fold more potent than mesalamine in inhibiting CRC cell proliferation. After exposure to 2-14, cyclin D1 expression was reduced and G0/G1 phase cells accumulated. These events were preceded by activation of eukaryotic translation initiation factor 2-alpha kinase 3 (pancreatic endoplasmic reticulum eIF2alpha kinase), phosphorylation of eukaryotic translation initiation factor 2alpha, induction of activating transcription factor 4, and splicing of X-box binding protein 1 messenger RNA, events that define endoplasmic reticulum stress. Silencing of PERK restored cyclin D1 levels, allowing cells to overcome the cell-cycle block induced by 2-14. Mice injected with 2-14 developed fewer CRC xenograft-derived tumors. Moreover, 2-14 injection reduced the development of neoplastic lesions induced by azoxymethane and dextran sulfate sodium in mice.

The mesalamine derivative 2-14 inhibited CRC cell proliferation in vitro and prevented CRC progression in mouse models.

5-ASA-MMX (1.2 g/tablet) is a 5-aminosalicylic acid formulation, designed for once-daily dosing in the treatment of ulcerative colitis.

To evaluate the efficacy and safety of 5-ASA-MMX (2.4 g/day, once daily), compared with Asacol (2.4 g/day, twice daily) in the maintenance of left-sided UC, through a double-blind, double-dummy, parallel-group, randomized, comparator study.

In all, 331 patients with UC were randomized to receive either 5-ASA-MMX 2.4 g/day, once daily, or Asacol 2.4 g/day, twice daily, for 12 months. All patients were in remission for >or=1 month prior to the trial, with >or=1 documented relapse in the previous year. The co-primary endpoints of this study were the proportion of patients in clinical, and clinical and endoscopic remission following 12 months' treatment.

In the intent-to-treat population, excluding those with major protocol deviations, 68.0 and 65.9% patients in the 5-ASA-MMX and Asacol groups, respectively, were in clinical remission (P = 0.69), and 60.9 and 61.7% of patients, respectively, were in clinical and endoscopic remission (P = 0.89). Diary card data revealed statistically significant treatment differences favouring 5-ASA-MMX. Both treatments were similarly tolerated.

Once-daily 5-ASA-MMX is similarly effective with a comparable safety profile to Asacol administered twice daily, for the maintenance treatment of ulcerative colitis.

The pharmacokinetics and safety of Asacol (Tillotts Pharma AG, Ziefen, Switzerland), which has been used worldwide to treat ulcerative colitis and Crohn's disease, were studied in Japanese healthy male volunteers.

Drug plasma concentrations and urinary and fecal excretions after a single dose (400-4800 mg) and multiple doses (3600 mg/day for 7 days) were investigated.

All adverse events were "not serious." The peak plasma concentration (C max) was reached at 12.3-18.0 hours after a single dose, and the C max and area under the plasma concentration-time curve (AUC) of mesalazine and its N-acetyl metabolite were proportional to the doses. The C max and AUC in non-Japanese subjects reported in the literature were closely correlated to findings in Japanese subjects, and external excretions were also similar in the Japanese and non-Japanese subjects.

Asacol was safe and well tolerated in this Japanese population, and the non-Japanese clinical data could be extrapolated to the Japanese population.

Induction and maintenance of remission, mucosal healing, the avoidance of surgical intervention, and decreasing the likelihood of cancer developing are the primary therapeutic goals in ulcerative colitis (UC). For the traditional therapies, 5-aminosalicylic acid (including mesalamine), corticosteroids, and thiopurines (azathioprine and mercaptopurine), there are major changes evolving in terms of formulation, patterns of use, and appreciation of long-term benefits and toxicities. The calcineurin inhibitors cyclosporin and tacrolimus, and infliximab, have recently defined, well-established roles. Preliminary supportive evidence is emerging in relation to novel antiinflammatory molecules such as curcumin, manipulation of the bacterial flora, enhancement of the mucosal barrier, and direct epithelial restoration. For patients in whom the disease is resistant to standard simple therapies, strategies are required to integrate these developing and new therapies into clinical practice. This review aims to highlight the evidence supporting new patterns of use of existing therapies and new therapies, and to devise therapeutic pathways that incorporate these new treatments. We propose how treatment might be optimized to improve the outcome in patients with mild-to-moderately active UC, chronic active UC, resistant proctitis, and fulminant UC.