Spread and distribution of 5-ASA colonic foam and 5-ASA enema in patients with ulcerative colitis

Quality by Design Perspective for Designing Foam-based Formulation: Current State of Art

Foam-based delivery systems contain one or more active ingredients and dispersed solid or liquid components that transform into gaseous form when the valve is actuated. Foams are an attractive and effective delivery approach for medical, cosmetic, and pharmaceutical uses. The foams-based delivery systems are gaining attention due to ease of application as they allow direct application onto the affected area of skin without using any applicator or finger, hence increasing the compliance and satisfaction of the patients. In order to develop foam-based delivery systems with desired qualities, it is vital to understand which type of material and process parameters impact the quality features of foams and which methodologies may be utilized to investigate foams. For this purpose, Quality-by-Design (QbD) approach is used. It aids in achieving quality-based development during the development process by employing the QbD concept. The critical material attributes (CMAs) and critical process parameters (CPPs) were discovered through the first risk assessment to ensure the requisite critical quality attributes (CQAs). During the initial risk assessment, the high-risk CQAs were identified, which affect the foam characteristics. In this review, the authors discussed the various CMAs, CPPs, CQAs, and risk factors associated in order to develop an ideal foam-based formulation with desired characteristics.

Efficacy of Pharmacological Agents for Ulcerative Proctitis: A Systematic Literature Review

BACKGROUND

Ulcerative proctitis is a common and often highly symptomatic form of inflammatory bowel disease. We performed a systematic review to assess the efficacy of different therapies in the management of patients with ulcerative proctitis.

METHODS

We identified randomized controlled trials in adults with ulcerative proctitis treated with oral or topical therapies for induction of response or remission, or prevention of relapse.

RESULTS

A total of 32 randomized controlled trials were included [27 induction/2839 participants, five maintenance/334 participants]. Follow-up varied from 3 to 8 weeks for induction, and from 6 to 24 months for maintenance of remission. 5-Aminosalicylic acid [5-ASA] suppository was the most frequently evaluated treatment [14/32, 43.7%], followed by steroid enema [7/32, 21.9%]. Topical 5-ASA demonstrated effectiveness for induction of clinical response or remission and prevention of relapse in several studies. Combined topical steroids and 5-ASA was more effective than topical 5-ASA or topical steroids alone to induce response [100% of patients for combination vs 70% for beclomethasone alone and 76% for 5-ASA alone]. One observational study suggested azathioprine may be effective in patients with ulcerative proctitis. Only two cohort studies evaluated the efficacy of tumour necrosis factor inhibitors in ulcerative proctitis. Small molecules, anti-integrins and anti-interleukin therapies have not been evaluated in isolated ulcerative proctitis.

CONCLUSION

The role of topical 5-ASA as a treatment for ulcerative proctitis has been confirmed in this systematic literature review, for induction and maintenance of remission. Future trials are needed to investigate the efficacy of more recent and upcoming drug classes in patients with ulcerative proctitis.

Novel Budesonide Suppository and Standard Budesonide Rectal Foam Induce High Rates of Clinical Remission and Mucosal Healing in Active Ulcerative Proctitis: a Randomised, Controlled, Non-inferiority Trial

BACKGROUND AND AIMS

Proctitis is the least extensive type of ulcerative colitis, for which rectal therapy is rarely studied and is underused. This study evaluated the efficacy, safety, and patient's preference of a novel formulation of budesonide suppository 4 mg, compared with a commercially available budesonide rectal foam 2 mg, for the treatment of mild to moderate ulcerative proctitis.

METHODS

This was a randomised, double-blind, double-dummy, active-controlled trial. Patients were randomly assigned in a 1:1 ratio to receive either budesonide 4 mg suppository or budesonide 2 mg foam once daily for 8 weeks. The co-primary endpoints were changes from baseline to Week 8 in clinical symptoms, for which clinical remission was defined as having a modified Ulcerative Colitis-Disease Activity Index [UC-DAI] subscore for stool frequency of 0 or 1 and a subscore for rectal bleeding of 0, and mucosal healing, defined as having a modified UC-DAI subscore for mucosal appearance of 0 or 1. Using a more stringent criterion, we additionally analysed deepened mucosal healing, which was defined as a mucosal appearance subscore of 0. Patient's preference, physician's global assessment, and quality of life were also assessed and analysed.

RESULTS

Overall, 286 and 291 patients were included in the 4 mg suppository and 2 mg foam groups, respectively. Budesonide 4 mg suppository met the prespecified criterion for non-inferiority to the 2 mg foam in both co-primary endpoints of clinical remission and mucosal healing. Secondary endpoints consistently supported the non-inferiority of the suppository. Trends in favour of the suppository were observed in the subgroup of mesalazine non-responders. More patients reported a preference for the suppository over rectal foam.

CONCLUSIONS

In patients with ulcerative proctitis, budesonide 4 mg suppository was non-inferior to budesonide 2 mg foam in efficacy, and both were safe and well tolerated.

Foams as unique drug delivery systems

Foams are multiphase systems found throughout nature. We meet them equally often in our everyday life, starting with the foam in the morning espresso, where the foam should constitute 10% of the drink or in a glass of beer and ending with the evening bath with foam. These multiphase systems consist mainly of gas, which is separated by liquid or solid lamellae. The lamellae have a very large surface area and a small thickness, which results in their low stability. The foams in pharmaceutics are known for a long time as protective or therapeutic preparations for topical use. However, the physicochemical structure of both solid and liquid foams offers multiple fields of application in the modern therapy. For instance, owing to the unique structure, foams can be also used for parenteral use in the form of implants serving as a drug carrier and at the same time, a scaffold for regenerating the tissue. Foams can also be used orally in the form of controlled drug delivery systems that are potentially useful for sustained or targeted drug delivery. The article describes the unique advantages and features of foams that make them useful in modern pharmacotherapy.

Recommendations of the Spanish Working Group on Crohn's Disease and Ulcerative Colitis (GETECCU) on topical therapy in ulcerative colitis

Although most patients with ulcerative colitis should be given topical treatment, different studies have shown that they are underused in clinical practice. The purpose of this article is to answer 10 specific questions about which drugs are available for topical use in the treatment of ulcerative colitis, and their characteristics in terms of formulation, dosage, presentation, application and proximal distribution of rectal-administered drugs. The efficacy of available topical drugs and the benefits of combining different formulations and routes of administration, and their usefulness during disease remission are evaluated. Finally, a series of recommendations addressed to patients are given on the correct application of topical treatment.

An In Situ Gelling System for the Local Treatment of Inflammatory Bowel Disease (IBD). The Loading of Maqui (Aristotelia Chilensis) Berry Extract as an Antioxidant and Anti-Inflammatory Agent

The aim of the present work was the development of an innovative in situ gelling system, to be applied on the mucosa of the distal colon via rectal route. The system consisted of three polymers having different functions: gellan (GG), able to jellify in presence of ions; methylcellulose (MC), a thermosensitive polymer with a gelation temperature close to 50 °C; and hydroxypropylcellulose (HPC), a mucoadhesive polymer. The three polymers were able to act synergistically, increasing the permanence of the vehicle on the mucosa and forming a protective gel layer. A DoE approach, "simplex centroid mixture design," was used to identify the optimal quantitative composition of the vehicle. The response variables considered were: vehicle viscosity at room temperature; increase in vehicle viscosity on increasing temperature (from room to physiological value) and upon dilution with simulated colonic fluid (SCF); and viscoelastic behavior, thixotropic area, and mucoadhesion properties of the gel formed at 37 °C upon dilution in SCF. The optimized vehicle was loaded with maqui berry extract (MBE), known for its antioxidant and anti-inflammatory properties. MBE loading (0.5% w/w) into the vehicle improved rheological and mucoadhesive properties of the formulation. Both MBE and the optimized vehicle were not cytotoxic towards human fibroblasts and Caco-2 cells. Moreover, the optimized vehicle did not affect MBE antioxidant properties.

Clinical Pharmacokinetic and Pharmacodynamic Considerations in the Treatment of Inflammatory Bowel Disease

According to recent clinical consensus, pharmacotherapy of inflammatory bowel disease (IBD) is, or should be, personalized medicine. IBD treatment is complex, with highly different treatment classes and relatively few data on treatment strategy. Although thorough evidence-based international IBD guidelines currently exist, appropriate drug and dose choice remains challenging as many disease (disease type, location of disease, disease activity and course, extraintestinal manifestations, complications) and patient characteristics [(pharmaco-)genetic predisposition, response to previous medications, side-effect profile, necessary onset of response, convenience, concurrent therapy, adherence to (maintenance) therapy] are involved. Detailed pharmacological knowledge of the IBD drug arsenal is essential for choosing the right drug, in the right dose, in the right administration form, at the right time, for each individual patient. In this in-depth review, clinical pharmacodynamic and pharmacokinetic considerations are provided for tailoring treatment with the most common IBD drugs. Development (with consequent prospective validation) of easy-to-use treatment algorithms based on these considerations and new pharmacological data may facilitate optimal and effective IBD treatment, preferably corroborated by effectiveness and safety registries.

Physiological and Pharmaceutical Considerations for Rectal Drug Formulations

Although the oral route is the most convenient route for drug administration, there are a number of circumstances where this is not possible from either a clinical or pharmaceutical perspective. In these cases, the rectal route may represent a practical alternative and can be used to administer drugs for both local and systemic actions. The environment in the rectum is considered relatively constant and stable and has low enzymatic activity in comparison to other sections of the gastrointestinal tract. In addition, drugs can partially bypass the liver following systemic absorption, which reduces the hepatic first-pass effect. Therefore, rectal drug delivery can provide significant local and systemic levels for various drugs, despite the relatively small surface area of the rectal mucosa. Further development and optimization of rectal drug formulations have led to improvements in drug bioavailability, formulation retention, and drug release kinetics. However, despite the pharmaceutical advances in rectal drug delivery, very few of them have translated to the clinical phase. This review will address the physiological and pharmaceutical considerations influencing rectal drug delivery as well as the conventional and novel drug delivery approaches. The translational challenges and development aspects of novel formulations will also be discussed.

Budesonide Suppositories Are Effective and Safe for Treating Acute Ulcerative Proctitis

BACKGROUND & AIMS

Although proctitis is the most limited form of ulcerative colitis, it causes unpleasant symptoms. Topical mesalamine, the standard treatment, is not always effective. We conducted a randomized phase 2 trial to determine the efficacy and safety of 2 doses of a budesonide suppository vs mesalamine suppositories vs combined budesonide and mesalamine suppositories for proctitis.

METHODS

We performed a prospective, double-blind, double-dummy, multicenter trial in 337 patients with active proctitis to compare the efficacies of 4 different suppository treatments. Patients were randomly assigned to groups given 2 mg budesonide suppositories (2 mg BUS; n = 89 patients), 4 mg BUS (n = 79), 1 g mesalamine suppositories (1 g MES; n = 81), or the combination of 2 mg BUS and 1 g MES (n = 88). The study was performed from November 2013 through July 2015 at 36 study sites in Europe and Russia. The primary end point was the time to resolution of clinical symptoms, defined as the first of 3 consecutive days with a score of 0 for rectal bleeding and stool frequency.

RESULTS

The mean time to resolution of symptoms in the 4 mg BUS (29.8 days) and combination of 2 mg BUS and 1 g MES (29.3 days) groups resembled that of the standard 1 g MES treatment (29.2 days), but was significantly longer in the 2 mg BUS group (35.5 days). Furthermore, proportions of patients with deep, clinical, and endoscopic remission, as well as mucosal healing, were similar among the 1 g MES, 4 mg BUS, and combination therapy groups, but significantly lower in the group that received 2 mg BUS. No safety signals were observed, and the patients' treatment acceptance was high (67%-85% of patients).

CONCLUSIONS

In a multicenter randomized trial, we found that the efficacy and safety of 4 mg BUS in treatment of active proctitis did not differ significantly from those of 1 g MES. Budesonide suppositories offer an alternative therapy to mesalamine for topical treatment of proctitis. Clinicaltrialsregister.eu no: 2012-003362-41.

Alternative foaming agents for topical treatment of ulcerative colitis

Approximately 907,000 Americans currently suffer from ulcerative colitis, a condition characterized by inflammation of the large intestine or rectum. Treatment of this disease often includes anti-inflammatory medication or immunosuppressants. Here foams are an attractive delivery platform, offering relatively high bioavailability, low systemic exposure, and improved patient comfort. However, the surfactants that generate these foams may adversely affect the diseased mucosa. Therefore, this project evaluated two alternative surfactants for use in topical drug delivery platforms: sodium caseinate and l-α-phosphatidylcholine. Both were compared to the biocompatible surfactant Pluronic^® F-127 using stability and density tests, and biocompatibility tests performed on mini-guts. Sodium caseinate foams were less stable but denser than Pluronic^® foams; however, they exhibited an unexpectedly low shelf-life. l-α-phosphatidylcholine was an unsuccessful primary foaming agent owing to poor foamability at low concentrations. Mini-gut growth rates were not significantly altered by surfactants, while morphology and an MTT assay identified Pluronic^® as the most biocompatible surfactant at higher concentrations. These results clarify the possible challenges that the tested surfactants may present in topical delivery platforms and show the relevance of permeability to tissue-surfactant interaction tests. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 1448-1456, 2018.

Nanoparticulate Drug Delivery Systems Targeting Inflammation for Treatment of Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a chronic, idiopathic inflammatory set of conditions that can affect the entire gastrointestinal (GI) tract and is associated with an increased risk of colorectal cancer. To date there is no curative therapy for IBD; therefore life-long medication can be necessary for IBD management if surgery is to be avoided. Drug delivery systems specific to the colon have improved IBD treatment and several such systems are available to patients. However, current delivery systems for IBD do not target drugs to the site of inflammation, which leads to frequent dosing and potentially severe side effects that can adversely impact patients' adherence to medication. There is a need for novel drug delivery systems that can target drugs to the site of inflammation, prolong local drug availability, improve therapeutic efficacy, and reduce drug side effects. Nanoparticulate (NP) systems are attractive in designing targeted drug delivery systems for the treatment of IBD because of their unique physicochemical properties and capability of targeting the site of disease. This review analyzes the microenvironment at the site of inflammation in IBD, highlighting the pathophysiological features as possible cues for targeted delivery; discusses different strategies and mechanisms of NP targeting IBD, including size-, charge-, ligand-receptor, degradation- and microbiome-mediated approaches; and summarizes recent progress on using NPs towards improved therapies for IBD. Finally, challenges and future directions in this field are presented to advance the development of targeted drug delivery for IBD treatment.

Baseline Oral 5-ASA Use and Efficacy and Safety of Budesonide Foam in Patients with Ulcerative Proctitis and Ulcerative Proctosigmoiditis: Analysis of 2 Phase 3 Studies

BACKGROUND

Rectal budesonide foam is a second-generation corticosteroid efficacious for active mild to moderate ulcerative proctitis and ulcerative proctosigmoiditis. This subgroup analysis examined the impact of baseline oral 5-aminosalicylic acid (5-ASA) on the efficacy and safety of budesonide foam in patients with mild to moderate ulcerative proctitis or ulcerative proctosigmoiditis.

METHODS

Patients received budesonide foam 2 mg/25 mL twice daily for 2 weeks, then once daily for 4 weeks, or placebo, with or without continued stable dosing of baseline oral 5-ASAs, for remission induction at week 6 (primary endpoint) in 2 identically designed, randomized, double-blind, phase 3 studies.

RESULTS

Of the 267 and 279 patients randomized to treatment with budesonide foam or placebo (pooled population), 55.1% and 55.2%, respectively, reported baseline 5-ASA use. A significantly greater percentage of patients achieved remission with budesonide foam versus placebo, either with (42.2% versus 31.8%, respectively; P = 0.03) or without (40.0% versus 14.4%; P < 0.0001) baseline 5-ASA use at week 6. A significantly greater percentage of patients achieved a Modified Mayo Disease Activity Index rectal bleeding subscale score of 0 at week 6, regardless of baseline 5-ASA use (5-ASA, 50.3% versus 35.7%; P = 0.003: no 5-ASA, 45.8% versus 19.2%; P < 0.0001). The frequency of adverse events was comparable between groups, regardless of baseline 5-ASA use.

CONCLUSIONS

Budesonide foam was efficacious and safe for induction of remission of mild to moderate ulcerative proctitis and ulcerative proctosigmoiditis in patients receiving oral 5-ASA at baseline and those who were not (Clinicaltrials.gov: NCT01008410 and NCT01008423).

Review article: The pharmacokinetics and pharmacodynamics of drugs used in inflammatory bowel disease treatment

BACKGROUND

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.

RESULTS

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.

Pathogenesis, diagnosis, and management of ulcerative proctitis, chronic radiation proctopathy, and diversion proctitis

Chronic proctitis refers to persistent or relapsing inflammation of the rectum, which results from a wide range of etiologies with various pathogenic mechanisms. The patients may share similar clinical presentations. Ulcerative proctitis, chronic radiation proctitis or proctopathy, and diversion proctitis are the 3 most common forms of chronic proctitis. Although the diagnosis of these disease entities may be straightforward in the most instances based on the clinical history, endoscopic, and histologic features, differential diagnosis may sometimes become problematic, especially when their etiologies and the disease processes overlap. The treatment for the 3 forms of chronic proctitis is different, which may shed some lights on their pathogenetic pathway. This article provides an overview of the latest data on the clinical features, etiologies, diagnosis, and management of ulcerative proctitis, chronic radiation proctopathy, and diversion proctitis.

Budesonide Foam Has a Favorable Safety Profile for Inducing Remission in Mild-to-Moderate Ulcerative Proctitis or Proctosigmoiditis

BACKGROUND

Budesonide foam, a rectally administered, second-generation corticosteroid with extensive hepatic first-pass metabolism, is efficacious for the treatment of mild-to-moderate ulcerative proctitis and ulcerative proctosigmoiditis.

AIM

The aim of this study was to comprehensively assess the safety and pharmacokinetic profile of budesonide foam.

METHODS

Data from five phase III studies were pooled to further evaluate safety, including an open-label study (once-daily treatment for 8 weeks), an active-comparator study (once-daily treatment for 4 weeks), and two placebo-controlled studies and an open-label extension study (twice-daily treatment for 2 weeks, then once daily for 4 weeks). Data from the placebo-controlled studies and two phase I studies (i.e., patients with mild-to-moderate ulcerative colitis and healthy volunteers) were pooled to evaluate the pharmacokinetics of budesonide foam.

RESULTS

A similar percentage of patients reported adverse events in the budesonide foam and placebo groups, with the majority of adverse events being mild or moderate in intensity (93.3 vs 96.0%, respectively). Adverse events occurred in 41.4 and 36.3% of patients receiving budesonide foam and placebo, respectively. Mean morning cortisol concentrations remained within the normal range for up to 8 weeks of treatment; there were no clinically relevant effects of budesonide foam on the hypothalamic-pituitary-adrenal axis. Population pharmacokinetic analysis demonstrated low systemic exposure after budesonide foam administration.

CONCLUSIONS

This integrated analysis demonstrated that budesonide foam for the induction of remission of distal ulcerative colitis is safe overall, with no clinically relevant effects on the hypothalamic-pituitary-adrenal axis.

Long-term efficacy and safety of once-daily mesalazine granules for the treatment of active ulcerative colitis

In 1977, 5-aminosalicylic acid (5-ASA) was discovered as a therapeutically active moiety of sulfasalazine (SASP) and was launched for topical and oral therapy of ulcerative colitis (UC) in 1984. As a first-step, delivery systems had to be developed to protect 5-ASA against absorption in the upper gastrointestinal tract, resulting in different and competing strategies (azo compounds, controlled release, and pH-dependent release). In a second step, at the beginning of the new century, coinciding with the expiration of patent protection for the first 5-ASA formulations, two component composite release mechanisms (pH-dependent and controlled release) were developed. Furthermore, the drug was formulated as granules instead of tablets, allowing higher unit strengths compared with tablets. Neither Salofalk Granu-Stix^®, nor MMX 5-ASA, nor Pentasa^® granules have initially been developed for once-daily (OD) dosing. A review of the achievements of 20 years of 5-ASA development has demonstrated that 5-ASA has equal efficacy compared with SASP at best, that there are no measurable differences in efficacy between various 5-ASA preparations, and that in a group of patients tolerating SASP, adverse event profiles of SASP and 5-ASA did not differ significantly, with SASP being the far cheaper substance. Therefore, drug adherence came into focus as a new goal for improving UC therapy. Although adherence is a complex and multifactorial construct, a simple dosing schedule may contribute to higher drug adherence and better efficacy of treatment. Simultaneously, the US 5-ASA market, estimated to be worth US$1.4 billion, is expected to grow continuously. Naturally, this very competitive market is not only driven by scientific progress but also by commercial interests. Thus, patents for minor changes to the formulation may serve as protection against drug companies trying to launch generic versions. Randomized controlled trials performed on OD dosing in induction of remission have demonstrated that OD administration of 5-ASA is as effective as conventional dosing in mild to moderate active UC. The three 5-ASA products MMX, Salofalk^®, and Pentasa^® employed in those studies so far have not shown differences in efficacy between OD and conventional dosing. No differences regarding safety outcomes have been detected between OD and conventional dosing, including incidence of adverse events, serious adverse events, or withdrawal from treatment due to an adverse event. Although the majority of patients prefer OD dosing to conventional dosing, it was not possible to detect differences in adherence between OD and multiple dose regimens in the clinical trial setting. Well-designed and controlled large-scale community-based studies are necessary to further investigate and prove the point of improved long-term adherence and treatment efficacy in OD dosing.

Topical therapy is underused in patients with ulcerative colitis

The availability of new topical preparations for the treatment of left sided ulcerative colitis offers a therapy optimization for many patients. Rectal application of steroids and 5-aminosalicylic acid (5-ASA) is associated with fewer side effects and has a higher therapeutic efficacy in left-sided colitis as compared to a systemic therapy. Therefore, we were interested in the use of topical therapy in patients with ulcerative colitis. The key question was whether topical treatment is more frequently used than oral therapy in patients with proctitis and left sided colitis. Data of 800 patients of the Swiss IBD cohort study were analyzed. Sixteen percent of patients of the cohort had proctitis, 21% proctosigmoiditis and 41% pancolitis. Topical therapy with 5-ASA or corticosteroids was given in 26% of patients with proctitis, a combined systemic and topical treatment was given in 13%, whereas systemic treatment with 5-ASA without topical treatment was given in 29%. Proportion of topical drug use decreased with respect to disease extension from 39% for proctitis to 13.1% for pancolitis (P=0.001). Patients with severe colitis received a significantly higher dose of topical 5-ASA than patients in remission. Side effects of topical or systemic 5-ASA or budesonide treatment were less frequently seen compared to other medications. Topical treatment was frequently stopped over time. The quality of life was the same in patients with limited disease compared to patients with pancolitis. Topical treatment in proctitis patients was underused in Switzerland. Since topical treatment is safe and effective it should be used to a larger extend.

Simulated comparison of topical and oral formulations of 5-aminosalicylate for the treatment of ulcerative colitis

BACKGROUND

5-Aminosalicylate (5-ASA) formulations are approved for the treatment of ulcerative colitis (UC). Determination of the colonic pharmacokinetics of 5-ASA is challenging. A dynamic model of 5-ASA colonic amounts after oral delayed-release 5-ASA (Asacol), oral extended delayed-release 5-ASA (Lialda), 5-ASA enema (Rowasa), foam and suppositories (Canasa) was developed to determine the colonic kinetics of these agents.

METHODS

We created a model with Stella software. Colonic 5-ASA in the right, transverse, descending, sigmoid colon, and rectum were estimated for adults after recommended doses of the above formulations. Simulations of active mild/moderate UC and in remission were performed and compared using Student's t-test for differences in means.

RESULTS

For UC in remission, the highest amounts of 5-ASA were from Asacol in the right and transverse colon (P < 0.01), Lialda in the descending and sigmoid colon (P < 0.01), and Rowasa in the rectum (P < 0.01). For active UC, sigmoid amounts were highest with foam (P < 0.01), and rectal amounts highest with Rowasa (P < 0.01). Differences in rectosigmoid amounts of 5-ASA from enemas and suppositories for UC in remission occurred based on the relationship between the timing of administration relative to the daily bowel movement (P < 0.01).

CONCLUSIONS

Compared to Asacol, Lialda results in higher 5-ASA amounts in the left colon. Asacol with Rowasa provides highest 5-ASA amounts across the entire colon. Higher 5-ASA amounts from topical formulations occur when the insertion occurs soon after the daily bowel movement. This model provides a rationale for further investigation.

Common misconceptions about 5-aminosalicylates and thiopurines in inflammatory bowel disease

Misconceptions are common in the care of patients with inflammatory bowel disease (IBD). In this paper, we state the most commonly found misconceptions in clinical practice and deal with the use of 5-aminosalicylates and thiopurines, to review the related scientific evidence, and make appropriate recommendations. Prevention of errors needs knowledge to avoid making such errors through ignorance. However, the amount of knowledge is increasing so quickly that one new danger is an overabundance of information. IBD is a model of a very complex disease and our goal with this review is to summarize the key evidence for the most common daily clinical problems. With regard to the use of 5-aminosalicylates, the best practice may to be consider abandoning the use of these drugs in patients with small bowel Crohn’ s disease. The combined approach with oral plus topical 5-aminosalicylates should be the first-line therapy in patients with active ulcerative colitis; once-daily treatment should be offered as a first choice regimen due to its better compliance and higher efficacy. With regard to thiopurines, they seem to be as effective in ulcerative colitis as in Crohn’ s disease. Underdosing of thiopurines is a form of undertreatment. Thiopurines should probably be continued indefinitely because their withdrawal is associated with a high risk of relapse. Mercaptopurine is a safe alternative in patients with digestive intolerance or hepatotoxicity due to azathioprine. Finally, thiopurine methyltransferase (TPMT) screening cannot substitute for regular monitoring because the majority of cases of myelotoxicity are not TPMT-related.

Clinical pharmacology of 5-ASA compounds in inflammatory bowel disease

Mesalamine has been the first-line of therapy in patients with inflammatory bowel disease (IBD) since the 1960s. This article serves as a review of the different 5-aminosalicylic acid compounds, release formulations, use and dosing in the treatment of IBD, in particular ulcerative colitis.

The Asia-Pacific consensus on ulcerative colitis

Inflammatory bowel disease (IBD) is increasing in many parts of the Asia-Pacific region. There is a need to improve the awareness of IBD and develop diagnostic and management recommendations relevant to the region. This evidence-based consensus focuses on the definition, epidemiology and management of ulcerative colitis (UC) in Asia. A multi-disciplinary group developed the consensus statements, reviewed the relevant literature, and voted on them anonymously using the Delphi method. The finalized statements were reviewed to determine the level of consensus, evidence quality and strength of recommendation. Infectious colitis must be excluded prior to diagnosing UC. Typical histology and macroscopic extent of the disease seen in the West is found in the Asia-Pacific region. Ulcerative colitis is increasing in many parts of Asia with gender distribution and age of diagnosis similar to the West. Extra-intestinal manifestations including primary sclerosing cholangitis are rarer than in the West. Clinical stratification of disease severity guides management. In Japan, leukocytapheresis is a treatment option. Access to biologic agents remains limited due to high cost and concern over opportunistic infections. The high endemic rates of hepatitis B virus infection require stringent screening before initiating immune-suppressive agents. Vaccination and prophylactic therapies should be initiated on a case-by-case basis and in accordance with local practice. Colorectal cancer complicates chronic colitis. A recent increase in UC is reported in the Asia-Pacific region. These consensus statements aim to improve the recognition of UC and assist clinicians in its management with particular relevance to the region.

Butyrate-induced transcriptional changes in human colonic mucosa

Background

Fermentation of dietary fiber in the colon results in the production of short chain fatty acids (mainly propionate, butyrate and acetate). Butyrate modulates a wide range of processes, but its mechanism of action is mostly unknown. This study aimed to determine the effects of butyrate on the transcriptional regulation of human colonic mucosa in vivo.

Methodology/Principal Findings

Five hundred genes were found to be differentially expressed after a two week daily butyrate administration with enemas. Pathway analysis showed that the butyrate intervention mainly resulted in an increased transcriptional regulation of the pathways representing fatty acid oxidation, electron transport chain and oxidative stress. In addition, several genes associated with epithelial integrity and apoptosis, were found to be differentially expressed after the butyrate intervention.

Conclusions/Significance

Colonic administration of butyrate in concentrations that can be achieved by consumption of a high-fiber diet enhances the maintenance of colonic homeostasis in healthy subjects, by regulating fatty acid metabolism, electron transport and oxidative stress pathways on the transcriptional level and provide for the first time, detailed molecular insight in the transcriptional response of gut mucosa to butyrate.

Mesalamine foam enema versus mesalamine liquid enema in active left-sided ulcerative colitis

AIM

To determine in a noninferiority study whether mesalamine foam is as effective as mesalamine liquid enema for inducing clinical remission in patients with active left-sided ulcerative colitis (UC).

METHODS

In a multicenter investigator-blind trial, 375 patients with mild-to-moderate UC were randomized to receive mesalamine foam 1 g/80 mL/day or mesalamine liquid enema 1 g/100 mL/day for 4 wk (W). Inclusion criteria were: disease extension at least 5 cm from anorectal junction and not above splenic flexure and Clinical Activity Index (CAI) 1-4 > or = 4. Primary end point was clinical remission at W4 defined as a CAI 1-4 < or = 2. Noninferiority of the foam to liquid enema was declared if the lower limit of the 97.5% unilateral confidence interval (97.5% CI) of the difference in remission rates between foam and liquid enema groups was greater than -15% .

RESULTS

Remission rates at W4 in foam versus liquid were 68.3%versus 73.6% in per protocol (PP) population (lower limit of 97.5% CI -15.1%) and 66.7%versus 70.5% in intention-to-treat (ITT) population (97.5% CI -13.4%). Remission rates at W2 were 48.1 %versus 50.6% in ITT (97.5% CI -12.8%) and 49.1%versus 52.1% in PP (97.5% CI -13.8%) in foam versus liquid, respectively. Both treatments were well tolerated.

CONCLUSIONS

A 4-wk treatment of 1 g mesalamine foam induced a clinical remission in 68% patients versus 73% with 1 g mesalamine liquid enema. Although the noninferiority of mesalamine foam could not be strictly demonstrated at W4 in the PP analysis, it was achieved in the ITT population and at W2 in both populations. Mesalamine foam represents a therapeutic alternative to mesalamine liquid enema in patients with mild-to-moderate active proctitis and proctosigmoiditis.

A clinical trial on absorption and N-acetylation of oral and rectal mesalazine

BACKGROUND

Mesalazine (5-ASA) is a standard treatment for ulcerative colitis. Extent of absorption and N-acetylation determine systemic exposure to 5-ASA, and are thereby relevant for the safety of the treatment. The aim of the study was to compare absorption and N-acetylation of 5-ASA following rectal or oral drug administration. Healthy subjects were compared to patients with ulcerative colitis to evaluate the impact of chronic inflammation of colorectal mucosa on disposition of 5-ASA.

MATERIALS AND METHODS

First, 12 healthy adults were randomized to receive 2 g of 5-ASA by each of four different formulations: oral delayed release granules, 30 mL enema, 60 mL rectal foam, and 120 mL rectal foam. Second, 12 patients with active ulcerative colitis received 60 mL rectal foam. Pharmacokinetic analysis was performed by determination of 5-ASA and its acetylated, pharmacologically inactive metabolite (Ac-5-ASA) in plasma and urine.

RESULTS

First, systemic exposure to 5-ASA was markedly lower after rectal drug administration as compared to oral dosing (P < 0.001; e.g. median relative bioavailability of 60 mL rectal foam: 36%). Second, N-acetylation of rectal 5-ASA was lower in patients than in healthy subjects [area under the curve (AUC) ratio Ac-5-ASA/5-ASA: 1.6 +/- 0.5 vs. 2.3 +/- 0.4, mean +/- SD, P < 0.01]. High peak plasma concentrations of 5-ASA were correlated with high microscopic disease activity (r = 0.67, P < 0.05).

CONCLUSIONS

Rectal delivery of 5-ASA results in low systemic drug exposure with potentially reduced toxicity in comparison with oral drug administration. Chronic inflammation of colorectal mucosa might be a relevant source of variability in pharmacokinetics of 5-ASA.

Beclomethasone dipropionate versus mesalazine in distal ulcerative colitis: a multicenter, randomized, double-blind study

BACKGROUND

Topical beclomethasone diproprionate has shown efficacy in ulcerative colitis.

AIM

To assess, in a multicenter, randomized, double-blind study, the tolerability and safety of topical beclomethasone diproprionate (3mg) enema and foam versus mesalazine (2g) enema and foam in mild-moderate distal ulcerative colitis.

PATIENTS

In 15 referral gastrointestinal units, 99 patients with distal ulcerative colitis were enrolled. This number was lower than planned according to the statistical analysis, due to a low recruitment rate.

METHODS

Patients were randomly assigned to random preparations (beclomethasone diproprionate enema, beclomethasone diproprionate foam, mesalazine enema, mesalazine foam) once nightly for 8 weeks, with clinical and endoscopical assessment (Disease Activity Index score) at baseline (T0), 4 (T4) and 8 weeks (T8). Results were expressed as median and range (95% confidence interval). The efficacy was assessed by comparing the Disease Activity Index value at T4 and T8 by using the Student's t-test or the Wilcoxon-Mann-Whitney test.

RESULTS

Efficacy was comparable in the beclomethasone diproprionate or mesalazine groups at both T4 and T8 (response at T4: beclomethasone diproprionate 78% [95% confidence interval 0.6-0.8] versus mesalazine 79% [95% confidence interval 0.6-0.8]; T8: beclomethasone diproprionate 84% [95% confidence interval 0.7-0.9] versus mesalazine 90% [95% confidence interval 0.7-1.0]; p=n.s.; remission at T4: beclomethasone diproprionate 24% [95% confidence interval 0.1-0.3] versus mesalazine 28% [95% confidence interval 0.1-0.3]; remission at T8: beclomethasone diproprionate 36% [95% confidence interval 0.2-0.5] versus mesalazine 52% [95% confidence interval 0.3-0.6]; p=n.s.). The Disease Activity Index lowered at T4 and T8 versus T0 in the four groups (T4 versus T0: beclomethasone diproprionate foam Disease Activity Index 2 versus 6 p<0.0001; beclomethasone diproprionate enema 4 versus 6, mesalazine enema 3 versus 6, mesalazine foam 3.5 versus 7, p<0.001 for all three groups; T8 versus T0: p<0.01). The Disease Activity Index lowered at T8 versus T4 in the beclomethasone diproprionate enema and foam (Disease Activity Index: 2 versus 4 and 1 versus 4, respectively; p<0.05) and in the mesalazine enema (Disease Activity Index: 1.5, range 0-4 versus 3, range 0-12; p<0.01), but not in the mesalazine foam group (Disease Activity Index: 1, range 0-9 versus 3.5, range 0-8; p=n.s.). The safety profile was favourable for all groups.

CONCLUSIONS

Beclomethasone diproprionate and mesalazine enema and foam show a comparable tolerability and efficacy in mild active distal ulcerative colitis.

Review article: aminosalicylates for distal colitis

About two-thirds of patients with ulcerative colitis have an inflammatory involvement distal to the splenic flexure and therefore may be effectively treated with topical treatment. This allows the delivery of the active drug directly to the site of inflammation, limiting the systemic absorption and the potential side effects. Topical aminosalicylate therapy is the most effective approach, provided that the formulation reaches the upper extent of the disease. Suppositories should be considered the treatment of choice for proctitis and distal sigmoiditis. A 1 g Pentasa-suppository once daily induces a quicker clinical and endoscopic remission and was better tolerated than a 500-mg suppository twice daily. Enemas, foams and gel, thanks to their proximal spread, should be the treatment of choice for proctosigmoiditis and left-sided colitis. Oral aminosalicylates are less effective than topical therapies for patients with active disease; however, a combination of oral and topical aminosalicylates can be successfully tried in refractory patients. Topical aminosalicylates also play an important role in the maintenance of remission, and the combination of oral plus rectal 5-aminosalicylate is superior to the single agent. Patients who prefer not to continue on long-term rectal therapy can be treated with oral aminosalicylates.

Colonic spread and serum pharmacokinetics of budesonide foam in patients with mildly to moderately active ulcerative colitis

BACKGROUND

Local treatment with foams in patients suffering from ulcerative proctitis or proctosigmoiditis is considered a rational treatment option.

AIMS

To investigate colonic spread, safety, tolerability and acceptance of a newly developed budesonide foam formulation.

METHODS

Twelve patients (four females, eight males) with acute proctosigmoiditis or left-sided ulcerative colitis were rectally administered a single dose of [99Tcm]-labelled budesonide foam (Budenofalk; Dr Falk Pharma GmbH, Freiburg, Germany) containing 2 mg budesonide in 20 mL foam after diagnostic colonoscopy. Thereafter, the colonic spread was assessed by means of gamma-scintigraphy for 6 h. Serum samples were taken simultaneously.

RESULTS

Budesonide foam spread with a maximum between 11 and 40 cm, thus reaching the sigmoid colon in all patients. In some patients, the foam even extended into the distal third and the middle of the descending colon with maximum radioactivity at 4 h. Systemic budesonide absorption was rapid and pharmacokinetic data were comparable with published data on marketed budesonide enemas, with mean serum C(max) and AUC(0-8 h) values of 0.8 +/- 0.5 ng/mL and 3.7 +/- 1.9 ng h/mL, respectively. The new formulation was well accepted by all patients, who could retain the foam for at least 4 h.

CONCLUSIONS

In the majority of patients, budesonide foam effectively spread up to the left-sided colon and thus qualifies for the local treatment of proctosigmoiditis.

Long-term oral plus topical mesalazine in frequently relapsing ulcerative colitis

BACKGROUND

In cross-sectional studies, it was demonstrated that the therapeutic effect of mesalazine is closely related to its mucosal concentration.

AIM

This study was carried out to verify in a longitudinal study if it was possible to improve the clinical course of ulcerative colitis at high risk of recurrence by increasing mucosal mesalazine concentration.

METHODS

Eighteen consecutive ulcerative colitis patients on continuous oral 5-ASA treatment (2.4-3.2 g/day) in clinical remission who had had at least four moderate to severe relapses in the preceding 2 years (referred period) were assigned to assume oral (3.2-4.8 g/day) and topical (4 g/day) mesalazine in order to increase mucosal drug concentration and were followed up for 2 years (study period). The localisation of disease was 12 pancolitis, six left colitis. The number and severity of recurrences, number of visits and endoscopies, courses of steroids and days of hospitalisation were compared with those of the previous 2 years. Rank signed test for paired data was used for statistical analysis.

RESULTS

The total number of recurrences was significantly lower during the study period in comparison with that of referred period (8 versus 80, respectively, p < 0.0001). No courses of steroids or hospitalisation were necessary during study period in comparison with those of referred period (0 versus 33, p < 0.0001; 0 versus 93, p = 0.03, respectively). A total number of 249 visits were done during the referred period and 116 during the study period (p < 0.0001) with a total of 87 endoscopies during referred period and 44 during study period (p < 0.0001).

CONCLUSIONS

The continuous use of topical mesalazine associated with a high oral dosage significantly improves the clinical course of ulcerative colitis patients at high risk of relapse.

Review article: problematic proctitis and distal colitis

About two-thirds of patients with ulcerative colitis have an inflammatory involvement distal to the splenic flexure, and therefore may be effectively treated with topical treatment, allowing the delivery of the active drug directly to the site of inflammation and limiting systemic absorption and potential side-effects. Topical aminosalicylate therapy is the most effective approach, and most patients will benefit hugely, provided that the formulation reaches the upper extent of the disease. Therefore, the choice of topical preparation should be based on the proximal extent of the disease and on patient preference. Oral aminosalicylates are less effective than topical therapies; however, a combination of oral and topical aminosalicylates can be successful in refractory patients. Alternatives to aminosalicylates are the new glucocorticoids, budesonide and beclometasone dipropionate, either as enemas or oral formulations (only beclometasone dipropionate). A combination of oral or rectal new glucocorticoids with rectal aminosalicylates should be considered in patients refractory to either approach. When these measures fail, treatment with oral glucocorticoids is necessary. An intensive intravenous steroid regimen is also helpful for patients refractory to oral steroids. Alternative treatments include short-chain fatty acid enemas, nicotine enemas and patches, acetarsol suppositories, ciclosporin enemas and epidermal growth factor enemas. Several factors potentially having a negative impact on therapeutic response include concurrent enteric pathogens, coexistent irritable bowel syndrome, patient nonadherence to therapy, inadequate dosing and duration of therapy, and proximal progression of the disease. Surgical colectomy may be required in those rare patients refractory or intolerant to pharmacotherapy.

Review article: diagnosis, monitoring and treatment of distal colitis

The diagnostic work-up of ulcerative colitis at presentation is based on the collection of clinical, microbiological, radiological, endoscopic and histologic data. Serological markers are characterized by too low a sensitivity to be commonly utilized in clinical practice. Although endoscopic and histologic features are characterized by very high sensitivity and specificity for the diagnosis of ulcerative colitis, negative stool cultures and parasites are mandatory to exclude an infectious aetiology at presentation. The treatment of choice of an acute flare-up of distal ulcerative colitis is represented by oral or topical mesalazine, or a combination of both, whereas the use of topical or systemic steroids should be restricted to patients who prove to be refractory to first-line treatments. Preliminary data suggest that the achievement of endoscopic and histologic remission after an acute flare of the disease might be associated with a prolonged remission.

Oral and topical 5-aminosalicylic acid (mesalazine) in inducing and maintaining remission in mild-moderate relapse of ulcerative colitis: one-year randomised multicentre trial

BACKGROUND

The association of oral 5-aminosalicylic acid (mesalazine) and enema is effective in treatment of mild-moderate forms of ulcerative colitis. However no study has been aimed at determining optimal duration of this association in active ulcerative colitis.

AIM

To determine whether longer duration of therapy: 1. increases the rate of patients achieving remission, and 2. reduces relapse rate during the maintenance period in patients in remission.

PATIENTS AND METHODS

A total of 149 patients, (89 male, 60 female), were randomly assigned to a regimen with 5-aminosalicylic acid tablets 2.4 g/day associated with 5-aminosalycilic enema 2 g/day for a 4-week (n = 73) or 8-week regimen (n = 76). After this acute therapy, patients were submitted to clinical, endoscopic and histological examinations and those in remission were assigned to a follow-up (maintenance) period with oral mesalazine alone at a dosage of 1.2 g/day. A clinical visit, including laboratory tests, at 6 months and an endoscopic-histological control at 12 months were carried out to exclude symptoms and endoscopic-histological signs of activity. Relapse of disease, i.e., presence of clinical symptoms or abnormal laboratory tests, was confirmed by endoscopy and histology.

RESULTS

At end of acute phase, clinical, endoscopic and histological remission was comparable in the two groups: 42/76 (55%), in the 4-week, and 47/73 patients (64%), in the 8-week regimen. No difference was found stratifying patients according to extension of disease. Of these 89 patients in remission, 75 (34 from 4-week regimen; 41 from 8-week regimen) completed 12 months' follow-up. At end of follow-up, a similar percentage of patients in the 4-week regimen (50%) and 8-week regimen (51%) were still in remission. No significant difference between cumulative relapse rates of the two groups was found. Stratifying patients according to extension of disease, in the 8-week regimen group, those with left-sided colitis showed a higher remission rate than that of patients with diffuse colitis (66% versus 35%, p < 0.05). All regimens were well tolerated by most patients during the entire study period.

CONCLUSIONS

An additional 4 weeks of topical treatment does not increase the remission rate in patients with mild-moderate active ulcerative colitis but seems to reduce the probability of relapse in patients with left-sided colitis.

Bioequivalence testing for locally acting gastrointestinal products: what role for gamma scintigraphy?

Bioequivalence testing for locally acting gastrointestinal products is a challenging issue for both the pharmaceutical industry and the global regulatory authorities. It is widely accepted that for medicinal products not intended to be delivered into the systemic circulation, pharmacokinetic bioavailability cannot be used. However, it is becoming increasingly accepted that local availability may be assessed, where appropriate, by approaches that qualitatively reflect the presence of the active substance at the site of action. These methods must be specifically chosen for that combination of active substance and route of drug delivery. This paper argues for the use of gamma scintigraphy as a validated measure of local availability and bioequivalence for topically acting products administered to the gastrointestinal tract by the oral and rectal route.

Review article: treatment of mild to moderate ulcerative colitis and pouchitis

The meta-analyses of published trials have shown topical therapy with 5-aminosalicylic acid (5-ASA) to be the treatment of choice in active distal ulcerative colitis. Oral aminosalicylates are effective for both distal and extensive ulcerative colitis, but in distal colitis the rates of improvement and remission are usually lower than those reported for rectal 5-ASA therapy. An alternative to 5-ASA therapy is represented by the new steroids; budesonide and beclometasone dipropionate (BDP) enemas, the most extensively studied, have been shown to be as effective as conventional steroids but with a significantly lower inhibition of plasma cortisol. Patients who do not respond to 5-ASA or new steroids should be treated with oral steroids. Azathioprine or 6-mercaptopurine may be effective in patients who do not respond or cannot be weaned off steroids. Treatment of pouchitis is largely empirical and few controlled studies have been carried-out. Antibiotics are the treatment of choice and most patients make a good response to metronidazole or ciprofloxacin. Chronic refractory pouchitis may benefit from a prolonged course of a combination of antibiotics. Highly concentrated probiotics (VSL#3) are effective both for the prevention of pouchitis onset and the prevention of relapses.

Pharmacokinetic considerations in the treatment of inflammatory bowel disease

This review describes the pharmacokinetics of the major drugs used for the treatment of inflammatory bowel disease. This information can be helpful for the selection of a particular agent and offers guidance for effective and well tolerated regimens. The corticosteroids have a short elimination half-life (t1/2beta) of 1.5 to 4 hours, but their biological half-lives are much longer (12 to 36 hours). Most are moderate or high clearance drugs that are hepatically eliminated, primarily by cytochrome P450 (CYP) 3A4-mediated metabolism. Prednisone and budesonide undergo presystemic elimination. Any disease state or comedication affecting CYP3A4 activity should be taken into account when prescribing corticosteroids. Depending on the preparation used, 10 to 50% of an oral or rectal dose of mesalazine is absorbed. Rapid acetylation in the intestinal wall and liver (t1/2beta 0.5 to 2 hours) and transport probably by P-glycoprotein affect mucosal concentrations of mesalazine, which apparently determine clinical response. Any clinical condition influencing the release and topical availability of mesalazine might modify its therapeutic potential. Metronidazole has high (approximately 90%) oral bioavailability, with hepatic elimination characterised by a t1/2beta of 6 to 10 hours and a total clearance of about 4 L/h/kg. Ciprofloxacin is largely excreted unchanged both renally (about 45% of dose) and extrarenally (25%), with a relatively short t1/2beta (3.5 to 7 hours). Thus, renal function affects the systemic availability of ciprofloxacin. Both mercaptopurine and its prodrug azathioprine are metabolised to active compounds (6-thioguanine nucleotides; 6-TGN) by hypoxanthine-guanine phosphoribosyltransferase and to inactive metabolites by the polymorphically expressed thiopurine S-methyltransferase (TPMT) and xanthine oxidase. Patients with low TPMT activity have a higher risk of developing haemopoietic toxicity. Both mercaptopurine and azathioprine have a short t1/2beta (1 to 2 hours), but the t1/2beta of 6-TGN ranges from 3 to 13 days. Therapeutic response seems to be related to 6-TGN concentration. Almost complete bioavailability has been observed after intramuscular and subcutaneous administration of methotrexate, which is predominantly (85%) excreted as unchanged drug with a t1/2beta of up to 50 hours. Thus, renal function is the major determinant for disposition of methotrexate. Cyclosporin is slowly and incompletely absorbed. It is extensively metabolised by CYP3A4/5 in the liver and intestine (median t1/2beta and clearance 7.9 hours and 0.46 L/h/kg, respectively), and inhibitors and inducers of CYP3A4 can modify response and toxicity. Infliximab is predominantly distributed to the vascular compartment and eliminated with a t1/2beta between 10 and 14 days. No accumulation was observed when it was administered at intervals of 4 or 8 weeks. Methotrexate may reduce the clearance of infliximab from serum.

A new mesalazine foam enema (Claversal Foam) compared with a standard liquid enema in patients with active distal ulcerative colitis

BACKGROUND

Rectally administered mesalazine (5-aminosalicylic acid) is a recognized therapy for distal ulcerative colitis. It is frequently applied as a liquid enema. However, there are reasons (acceptability to the patient, more uniform topical dispersion and effective adhesion) to prefer a foam-based enema.

AIM

This study compared a foam enema (2 g mesalazine per day, Claversal Foam) with a standard liquid enema (4 g mesalazine per day, Salofalk enema).

METHODS

Patients with active distal ulcerative colitis, diagnosed according to standardized criteria, were treated for 4 weeks. The primary goal was clinical remission; endoscopic remission, histological changes, global assessment and standard safety measures were also analysed. A major subset of the patients also provided quality-of-life data.

RESULTS

Both foam and liquid enema gave good rates of clinical and endoscopic remission. The foam enema was shown to be as efficacious as the reference, even though the daily dose in the foam treatment contained only half as much active drug as in the reference treatment. Minor regional differences in efficacy were seen. The tolerabilities of the two formulations were comparable.

CONCLUSIONS

The foam enema offers a safe, efficacious and acceptable treatment for distal ulcerative colitis.

Comparative tolerability of treatments for inflammatory bowel disease

Despite limited understanding of therapeutic aetiopathogenesis of ulcerative colitis and Crohn's disease, there is a strong evidence base for the efficacy of pharmacological and biological therapies. It is equally important to recognise toxicity of the medical armamentarium for inflammatory bowel disease (IBD). Sulfasalazine consists of sulfapyridine linked to 5-aminosalicylic acid (5-ASA) via an azo bond. Common adverse effects related to sulfapyridine 'intolerance' include headache, nausea, anorexia, and malaise. Other allergic or toxic adverse effects include fever, rash, haemolytic anaemia, hepatitis, pancreatitis, paradoxical worsening of colitis, and reversible sperm abnormalities. The newer 5-ASA agents were developed to deliver the active ingredient of sulfasalazine while minimising adverse effects. Adverse effects are infrequent but may include nausea, dyspepsia and headache. Olsalazine may cause a secretory diarrhoea. Uncommon hypersensitivity reactions, including worsening of colitis, pancreatitis, pericarditis and nephritis, have also been reported. Corticosteroids are commonly prescribed for treatment of moderate to severe IBD. Despite short term efficacy, corticosteroids have numerous adverse effects that preclude their long term use. Adverse effects include acne, fluid retention, fat redistribution, hypertension, hyperglycaemia, psycho-neurological disturbances, cataracts, adrenal suppression, growth failure in children, and osteonecrosis. Newer corticosteroid preparations offer potential for targeted therapy and less corticosteroid-related adverse effects. Azathioprine and mercaptopurine are associated with pancreatitis in 3 to 15% of patients that resolves upon drug cessation. Bone marrow suppression is dose related and may be delayed. The adverse effects of methotrexate include nausea, leucopenia and, rarely, hypersensitivity pneumonia or hepatic fibrosis. Common adverse effects of cyclosporin include nephrotoxicity, hypertension, headache, gingival hyperplasia, hyperkalaemia, paresthesias, and tremors. These adverse effects usually abate with dose reduction or cessation of therapy. Seizures and opportunistic infections have also been reported. Antibacterials are commonly employed as primary therapy for Crohn's disease. Common adverse effects of metronidazole include nausea and a metallic taste. Peripheral neuropathy can occur with prolonged administration. Ciprofloxacin and other antibacterials may be beneficial in those intolerant to metronidazole. Newer immunosuppressive agents previously reserved for transplant recipients are under investigation for IBD. Tacrolimus has an adverse effect profile similar to cyclosporin, and may cause renal insufficiency. Mycophenolate mofetil, a purine synthesis inhibitor, has primarily gastrointestinal adverse effects. Biological agents targeting specific sites in the immunoinflammatory cascade are now available to treat IBD. Infliximab, a chimeric antibody targeting tumour necrosis factor-or has been well tolerated in clinical trials and early postmarketing experience. Additional trials are needed to assess long term adverse effects.

Efficacy and tolerability of mesalazine foam enema (Salofalk foam) for distal ulcerative colitis: a double-blind, randomized, placebo-controlled study

BACKGROUND

Rectal formulations of mesalazine are the treatment of choice in mildly to moderately active ulcerative colitis. A new foam formulation of mesalazine was developed to improve both drug delivery and patient acceptance.

METHODS

In this multicentre, randomized, double-blind, parallel-group study, 111 patients with mildly to moderately active proctitis, proctosigmoiditis, or left-sided ulcerative colitis received mesalazine foam enema or placebo enema (2 g mesalazine per day) for 6 weeks. Disease activity was monitored on the basis of the Clinical Activity Index, Endoscopic Index, Histological Index, and global efficacy assessment by the investigators. Safety assessments included the recording of adverse events, laboratory variables and vital signs.

RESULTS

Clinical remission was more frequent in the mesalazine group than the placebo group (65% vs. 40%; P=0.0082), particularly in patients with mild disease and patients with proctosigmoiditis. The frequency of patients with an endoscopic remission was higher in the mesalazine group (57%) than in the placebo group (37%). Similarly, 59% of patients receiving mesalazine but only 41% of those receiving placebo showed an improved Histological Index. The foam enemas were generally well-tolerated, and no treatment-related changes on laboratory variables and vital signs were noted.

CONCLUSIONS

Mesalazine foam enema was well-tolerated and was more effective than placebo in the treatment of patients with distal ulcerative colitis.

Clinical pharmacokinetics of slow release mesalazine

Slow release oral mesalazine (Pentasa) contains microgranules covered by a semipermeable ethylcellulose membrane. The microgranules continuously release their content from duodenum to ileum in a pH- and time-dependent way. About 75% of the microgranules pass into the colon, where further release is slower. This release pattern does not appear to be affected by food, diarrhoea or the simultaneous use of H2 antagonists. Rectal forms of mesalazine deliver active drug directly to the rectum and left colon. Plasma concentrations of mesalazine and its metabolite acetyl-5-aminosalicylic acid after oral or local administration are the result of systemic absorption and hepatic metabolism by N-acetyltransferase. Most studies report maximal plasma concentrations of less than 1 mg/L after oral administration of slow release mesalazine, much lower than those observed after uncoated mesalazine but generally higher than after azo-bound drugs such as sulfasalazine. Urinary recovery is an indicator of absorption and metabolism, and is lower after rectal administration (10 to 30%) than after oral administration (30 to 40%). Faecal recovery after oral administration of slow or delayed release mesalazine is lower than with azo-bound drugs. Mesalazine acts locally after absorption by colonic and ileal mucosa. Mean steady-state concentrations of 25.7+/-2.2 microg/kg wet weight are found in ileocolonic biopsy specimens from patients with irritable bowel syndrome treated for 1 week with slow release mesalazine 1.5 g/day. Intramucosal concentrations after slow release mesalazine differ little between healthy individuals and patients with inflammatory bowel disease. Although significant differences are found between the various aminosalicylates in release patterns and the resulting pharmacokinetic parameters, no differences in therapeutic effects have been found in comparative studies. High doses of oral mesalazine (2 to 4 g/day) are more effective than lower doses in the treatment of patients with mild to moderate active ulcerative colitis. High doses (4 g/day) are also effective in the treatment of Crohn's disease, predominantly in patients with ileitis. In contrast, no dose ranging effects were demonstrated with local treatment forms: mesalazine 1g enema seems sufficient for patients with distal colitis. Higher serum concentrations and urinary recoveries after the administration of slow or delayed release mesalazine compared with azo-bound drugs suggest a higher risk for renal adverse effects, although the reported occurrence is extremely low. Although preliminary data support an association between mucosal concentrations of mesalazine and its clinical activity, further studies are needed to correlate the effects of this drug with its pharmacokinetic parameters.

Putting rectal 5-aminosalicylic acid in its place: the role in distal ulcerative colitis

Oral aminosalicylates such as sulfasalazine and mesalamine are widely prescribed for the treatment of mild or moderately active distal ulcerative colitis. However, a critical review of the literature demonstrates that rectal 5-aminosalicylic acid (5-ASA) is the optimal therapy for this disease. Meta-analyses of published trials show that rectally delivered 5-ASA is superior to placebo and to conventional rectal corticosteroids in inducing remission of distal ulcerative colitis, whereas the combination of rectal 5-ASA with a rectal corticosteroid or oral aminosalicylate is superior to rectal 5-ASA alone. For maintaining remission of distal ulcerative colitis, rectal 5-ASA is significantly better than placebo and at least as effective as oral 5-ASA. The dosage forms available for rectal delivery include suppositories, foams, and liquid enemas, and selection among these preparations should be guided by the proximal extent of disease and patient preference. The efficacy of rectal 5-ASA is complemented by its low rate of reported adverse effects, which may reflect its reduced potential for systemic absorption. This review summarizes the evidence supporting the role of rectal 5-ASA as a first-line therapy for mild or moderately active distal ulcerative colitis, and offers guidelines for its use.

A new mesalazine gel enema in the treatment of left-sided ulcerative colitis: a randomized controlled multicentre trial

BACKGROUND

A new mesalazine rectal gel preparation (without propellant gas) has been recently developed to improve topical treatment in distal ulcerative colitis.

AIM

To evaluate the efficacy, safety and patient tolerability of mesalazine gel enema compared with mesalazine foam enema in the treatment of patients with acute left-sided ulcerative colitis.

METHODS

In a randomized multicentre investigator-blind parallel group trial, 103 patients with mild to moderate left-sided colitis or proctosigmoiditis were randomly allocated to mesalazine 2 g gel enema (n = 50 evaluable patients) and mesalazine 2 g foam enema (n = 53 evaluable patients) for 4 weeks. Clinical symptoms, endoscopic and histological findings were assessed at entry, 2 and 4 weeks. Patients' evaluation of treatment tolerability and acceptability was assessed at 2 and 4 weeks.

RESULTS

After 4 weeks of treatment, clinical remission was achieved by 76% of mesalazine gel enema-treated patients and 69% of patients treated with mesalazine foam enema (P = 0.608). Endoscopic remission rates at week 4 were 51 and 52% for the mesalazine gel and foam enemas, respectively (P = 0.925). Histological remission was achieved by 30% of patients in both groups. Patients reported that the new mesalazine gel preparation was significantly better tolerated than the foam enema. Patients in the foam group had significantly more difficulty in retention (25% vs. 6%, P < 0.05), abdominal bloating (50% vs. 26%, P < 0.005) and discomfort during administration (48% vs. 26%, P < 0.05).

CONCLUSION

The new mesalazine gel enema is efficacious and significantly better tolerated than the mesalazine foam enema.

[Pharmacokinetic data for different 5-aminosalicylic acid and budesonide preparations]

Different orally and rectally applicable forms of 5-ASA and budesonide have been developed to achieve sufficient high concentrations of the active moieties at the site of inflammation (small and/or large bowel) and to limit the systemic action of the drugs. This concept of drug targeting could be accomplished by both special galenic formulations and by utilizing the pharmacokinetic properties of the agents especially their high intestinal and hepatic presystemic elimination. Thus, 5-ASA and budesonide represent drugs of first choice in the treatment of Crohn's disease and ulcerative colitis. This review describes the various pharmacokinetic and (patho)physiologic factors and their impact on drug delivery and biological availability of the different 5-ASA and budesonide preparations.

Review article: issues in oral administration of locally acting glucocorticosteroids for treatment of inflammatory bowel disease

Inflammatory bowel diseases are treated in some cases by local administration of anti-inflammatory drugs. Local delivery of drugs in the colon following oral administration may lead to improved efficacy/side-effect profiles and may improve patient compliance. This review covers a number of issues important in the design of oral delivery systems of glucocorticosteroids for local therapy of colonic inflammation. The choice of specific glucocorticosteroids is based on the drug's physicochemical and pharmacological properties. The conditions under which an orally administered glucocorticosteroid (or other drug) must be delivered to treat ulcerative colitis are also discussed. These conditions include variations in local pH, transit throughout the gastrointestinal tract, the potential role of gut microflora, and drug dissolution in both the healthy and diseased large intestine. The effective delivery of topically-active glucocorticosteroids in ulcerative colitis and Crohn's colitis patients is complex, but if successful could improve their usefulness.

Comparison of oral with rectal mesalazine in the treatment of ulcerative proctitis

PURPOSE

The aim of our study was to compare the efficacy and safety of oral mesalazine with mesalazine suppositories in patients with active ulcerative proctitis.

PATIENTS AND METHODS

A four-week, randomized, single-blind trial was performed in 58 patients with active, histologically confirmed ulcerative proctitis (< or = 15 cm) to evaluate the efficacy and safety of oral 800-mg mesalazine tablets taken three times per day (n = 29) compared with 400 mg of mesalazine suppositories administered three times per day (n = 29). Patients were evaluated at study entry and after two and four weeks. Efficacy evaluations included a disease activity index, which represents a score with four variables: stools frequency, rectal bleeding, mucosal appearance, and physician's assessment of disease severity. Histologic activity was also assessed at study entry and after two and four weeks in accordance with the criteria by Truelove and Richard. Safety assessment included clinical laboratory parameters and adverse event reports.

RESULTS

There were no significant differences with regard to baseline comparisons of demographics and severity between the two treatment groups. Improvement in mean disease activity index score was significantly greater with suppositories compared with oral mesalazine, both at two-week and four-week visits (mean disease activity index scores at baseline, two, and four weeks: suppositories = 7.7, 2.59, and 1.48; tablets = 7.42, 5.72, and 3.48, respectively (P < 0.001)). The rate of histologic remission was significantly greater with suppositories compared with tablets both at two and four weeks (P < 0.01). There were no significant differences in adverse events or clinical laboratory results between treatment groups.

CONCLUSIONS

Results of this study indicate that treatment with mesalazine suppositories produces earlier and significantly better results than oral mesalazine in the treatment of active ulcerative proctitis.

Review article: Targeted drug delivery in treatment of intestinal diseases

Topical therapy within the treatment of intestinal diseases presents realistic formulation challenges for targeted drug delivery. Some relevant oral formulation concepts are reviewed. The basic principles employed are based mainly on differences in pH and metabolic activity between the different parts of the gastrointestinal tract. A successful example of targeted drug delivery within the treatment of Crohn's disease is presented. Topical therapy for the treatment of ulcerative colitis is also discussed. Physiological variations and influence of the disease and disease status present major challenges when deciding upon a suitable formulation principle.