MMX mesalamine: a novel high-dose, once-daily 5-aminosalicylate formulation for the treatment of ulcerative colitis

An Update on Current Pharmacotherapeutic Options for the Treatment of Ulcerative Colitis

The main goals of Ulcerative Colitis (UC) treatment are to both induce and maintain the clinical and endoscopic remission of disease, reduce the incidence of complications such as dysplasia and colorectal carcinoma and improve quality of life. Although a curative medical treatment for UC has not yet been found, new therapeutic strategies addressing specific pathogenetic mechanisms of disease are emerging. Notwithstanding these novel therapies, non-biological conventional drugs remain a mainstay of treatment. The aim of this review is to summarize current therapeutic strategies used as treatment for ulcerative colitis and to briefly focus on emerging therapeutic strategies, including novel biologic therapies and small molecules. To date, multiple therapeutic approaches can be adopted in UC and the range of available compounds is constantly increasing. In this era, the realization of well-designed comparative clinical trials, as well as the definition of specific therapeutic models, would be strongly suggested in order to achieve personalized management for UC patients.

Mesalazine and inflammatory bowel disease - From well-established therapies to progress beyond the state of the art

Inflammatory bowel disease incidence has been constantly rising for the past few decades. Current therapies attempt to mitigate its symptoms since no cure is established. The most commonly prescribed drug for these patients is 5-aminosalicylic acid (5-ASA). Due to the low rate and seriousness of side effects compared to other therapies, 5-ASA is still largely prescribed in many stages of inflammatory bowel disease, including scenarios where evidence suggests low effectiveness. Although commercialized formulations have come a long way in improving pharmacokinetics, it is still necessary to design and develop novel delivery systems capable of increasing effectiveness at different stages of the disease. In particular, micro- and nano-sized particles might be the key to its success in Crohn's disease and in more serious disease stages. This review provides an overview on the clinical significance of 5-ASA formulations, its limitations, challenges, and the most recent micro- and nanoparticle delivery systems being designed for its controlled release. Emergent alternatives for 5-ASA are also discussed, as well as the future prospects for its application in inflammatory bowel disease therapies.

Key Strategies to Optimize Outcomes in Mild-to-Moderate Ulcerative Colitis

Mesalamine (5-ASA) is the mainstay therapy in patients with mild-to-moderate active ulcerative colitis (UC). However, non-adherence to therapy and practice variability among gastroenterologists represent long-standing barriers, leading to poor outcomes. Additionally, targets to treat in UC are increasingly evolving from focusing on clinical remission to achieving endoscopic and histological healing. To date, systemic steroids are still recommended in non-responders to 5-ASA, despite their well-known side effects. Importantly, with the advent of new therapeutic options such as oral corticosteroids with topical activity (e.g., budesonide multimatrix system (MMX)), biologics, and small molecules, some issues need to be addressed for the optimal management of these patients in daily clinical practice. The specific positioning of these drugs in patients with mild-to-moderate disease remains unclear. This review aims to identify current challenges in clinical practice and to provide physicians with key strategies to optimize treatment of patients with mild-to-moderate UC, and ultimately achieve more ambitious therapeutic goals.

In Vitro Methods to Study Colon Release: State of the Art and An Outlook on New Strategies for Better In-Vitro Biorelevant Release Media

The primary focus of this review is a discussion regarding in vitro media for colon release, but we also give a brief overview of colon delivery and the colon microbiota as a baseline for this discussion. The large intestine is colonized by a vast number of bacteria, approximately 1012 per gram of intestinal content. The microbial community in the colon is complex and there is still much that is unknown about its composition and the activity of the microbiome. However, it is evident that this complex microbiota will affect the release from oral formulations targeting the colon. This includes the release of active drug substances, food supplements, and live microorganisms, such as probiotic bacteria and bacteria used for microbiota transplantations. Currently, there are no standardized colon release media, but researchers employ in vitro models representing the colon ranging from reasonable simple systems with adjusted pH with or without key enzymes to the use of fecal samples. In this review, we present the pros and cons for different existing in vitro models. Furthermore, we summarize the current knowledge of the colonic microbiota composition which is of importance to the fermentation capacity of carbohydrates and suggest a strategy to choose bacteria for a new more standardized in vitro dissolution medium for the colon.

Eudragit S100-Coated Chitosan Nanoparticles Co-loading Tat for Enhanced Oral Colon Absorption of Insulin

In order to improve oral absorption of insulin, especially the absorption at the colon, Eudragit S100® (ES)-coated chitosan nanoparticles loading insulin and a trans-activating transcriptional peptide (Tat) were employed as the vehicle. In vitro releases of insulin and Tat from ES-coated chitosan nanoparticles had a pH-dependant characteristic. A small amount of the contents was released from the coated nanoparticles at pH 1.2 simulated gastric fluid, while a fairly fast and complete release was observed in pH 7.4 medium. Caco-2 cell was used as the model of cellular transport and uptake studies. The results showed that the cellular transport and uptake of insulin for ES-coated chitosan nanoparticles co-loading insulin and Tat (ES-Tat-cNPs) were about 3-fold and 4-fold higher than those for the nanoparticles loading only insulin (ES-cNPs), respectively. The evaluations in vivo of ES-Tat-cNPs were conducted on diabetic rats and normal minipigs, respectively. The experimental results on rats revealed that the pharmacodynamical bioavailability of ES-Tat-cNPs had 2.16-fold increase compared with ES-cNPs. After oral administration of nanoparticle suspensions to the minipigs, insulin bioavailability of ES-Tat-cNPs was 1.73-fold higher than that of ES-cNPs, and the main absorption site of insulin was probably located in the colon for the two nanoparticles. In summary, this report provided an exploratory means for the improvement of oral absorption of insulin.

The effect of third-party reporting on adoption of evidence-based mesalazine regimens in ulcerative colitis: an observational study

BACKGROUND AND AIMS

The optimal mesalazine dosing strategy for ulcerative colitis (UC) continues to evolve. The current study aimed to explore whether documenting drug use could prompt changes in prescribing habits.

METHODS

In a multicenter, prospective, observational study, outpatients with active or quiescent UC were enrolled if they were receiving, or were planned to receive, sustained release mesalazine microgranules (Pentasa). Clinical and prescribing data were collected at study entry, after 2 and 8 weeks. Physician-reported influences on prescribing decisions were recorded at study entry.

RESULTS

360 patients were analyzed (203 active UC, 157 remission). Prior to study entry, the range of oral mesalazine doses was 0.50-6.00 g/day in active UC patients, and 0.50-4.00 g/day for patients in remission. These changed to 1.50-5.00 g/day and 1.00-4.00 g/day, respectively, at study entry with little change thereafter. Use of a single daily mesalazine dose increased from 16.7% to 58.0% of active cases during the study, and from 5.9% to 46.8% in remission cases. Gastroenterologists reported that their basis for prescription decision-making was most frequently medical experience (80.8%), followed by guidelines (67.2%), further education or colleagues' recommendations (50.0%) and current study results (20.0%).

CONCLUSION

In this analysis of mesalazine dosing in routine clinical practice, there was an improvement in adherence to European Crohn's and Colitis Organisation (ECCO) guidelines and in use of once-daily dosing, consistent with recent trial results, following documentation of dosing regimens. Written reporting of drug dosing schedules should be considered fundamental for chronic, complex diseases such as UC.

Once daily, high-dose mesalazine controlled-release tablet for colonic delivery: optimization of formulation variables using Box-Behnken design

The aim of this work was to statistically optimize a novel high-dose, mesalazine colonic delivery matrix system, potentially suitable for once daily administration, using simple wet granulation method. A hydrophobic-hydrophilic polymeric blend was used to manipulate drug release. A three-factor, three-level Box-Behnken design was used to construct polynomial models correlating the dependent and independent variables. Independent formulation variables were the percentages of the hydrophilic polymer Carbopol® 940, hydrophobic polymer Eudragit® RS, and the superdisintegrant croscarmellose sodium. The cumulative percentages of drug released at 6, 10, and 14 h were selected as dependent variables and restricted to 7.5-22.5% (Y(1)), 42.5-57.5 % (Y(2)), and 72.5-87.5% (Y(3)), respectively. A second-order polynomial equation fitted to the data was used to optimize the independent formulation variables. Based on Box-Behnken experimental design, different mesalazine release profiles were obtained. The optimized formulation containing 5.72% Carbopol®, 9.77% Eudragit® RS, and 1.45% croscarmellose sodium was prepared according to the software determined levels. It provided a release profile which was very close to the targeted release profile, where the calculated values of f(1) and f(2) were 8.47 and 67.70, respectively, and followed zero-order release kinetics.

Update on the management of ulcerative colitis

The treatment options for inflammatory bowel disease have expanded with the introduction of biological therapies. Recently published controlled clinical trials were searched and those that impact the clinical management of ulcerative colitis (UC) are discussed in this review. In the management of mild to moderate UC, mesalamine still remains the first choice of drug. The newly developed once daily formulations have shown equal efficacy to divided doses and possibly portend better compliance owing to a simplified regimen. In outpatients with moderate to severe UC, recent data indicate that infliximab induced and maintained remission leads to decreased colectomy rates and fewer hospitalizations. An alternative anti-tumor necrosis factor (TNF) agent, adalimumab, was also recently shown to be effective for induction of remission in moderate to severe UC. The use of immunosuppressives, such as azathioprine and mercaptopurine, is associated with decreased colectomy rates and thioguanine was shown to be effective in maintaining clinical remission in those who are intolerant to azathioprine/mercaptopurine. In hospitalized patients with steroid resistant severe UC, infliximab and tacrolimus may be alternatives to cyclosporine in those who are otherwise candidates for colectomy. Adequate long-term maintenance therapy with immunosuppressives or anti-TNF therapy is required after rescue therapy for a sustained benefit. Future research is needed to position the available anti-TNF agents and combined immunosuppressive therapy in the treatment of UC to achieve and maintain steroid free remission.

New light on the anti-colitic actions of therapeutic aminosalicylates: the role of heme oxygenase

Although a variety of pharmaceutical preparations of aminosalicylate are commonly used in the clinic for the control of inflammatory bowel disease, the mechanisms underlying their therapeutic actions remain unclear. Recent in vivo and in vitro studies have demonstrated that 5-aminosalicylic acid (5-ASA), regarded as the active moiety in aminosalicylate preparations such as sulfasalazine, can induce the heat shock protein, heme oxygenase-1 (HO-1) and up-regulate HO enzyme activity in the colon. As HO-1 can produce endogenous anti-oxidant and anti-inflammatory moieties such as bilirubin and carbon monoxide (CO), these findings suggest a novel mechanism of action for aminosalicylates, acting as anti-colitic agents through the up-regulation of HO-1 enzyme expression and activity.

Patient considerations in the management of ulcerative colitis: role of once-daily MMX mesalamine

Mesalamine and its derivatives are effective and well-tolerated therapies for ulcerative colitis. However, patient adherence to traditional mesalamine-based therapy is poor, and is often limited by heavy pill burdens and frequent dosing intervals. This can lead to ineffective disease control, impaired quality of life, and preventable morbidity and mortality. Previous studies have suggested that a once-daily mesalamine regimen would be strongly adhered to in the outpatient setting, but at that time no such formulation of mesalamine existed. In 2007, clinical trial data showed a novel, once-daily, multi-matrix (MMX) formulation of mesalamine to be effective in both remission induction and remission maintenance. This breakthrough in drug delivery allowed the unification of an effective therapeutic with a formulation that enables outpatients to be increasingly adherent to their medication. In theory, this might result in improved outpatient disease control and a decreased number of flares. As the use of MMX mesalamine increases, studies examining the outpatient community adherence rate need to be performed.