Effect of food on the pharmacokinetics of budesonide controlled ileal release capsules in patients with active Crohn's disease

Tissue re-distribution of budesonide in rats co-administrated with curcumin by ultra performance liquid chromatography-tandem mass spectrometry

Budesonide (BUD), a locally acting glucocorticoid with low side effects, is recommended in several Crohn's disease (CD) drug treatment guidelines as the first choice for early treatment. Nevertheless, the extensive first-pass effect mediated by P-glycoprotein (P-gp) and Cytochrome P450 3A4 (CYP3A4) leads to low bioavailability and limits further applications. Curcumin (CUR), a natural polyphenol derived from turmeric, has been found to influence the in vivo processes of drugs by affecting the activity of P-gp and CYP3A4. However, the pharmacokinetic interactions between BUD and CUR remains elusive, so an ultra high-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was established for the simultaneous determination of BUD and CUR in the tissue. The results showed that the area under the concentration-time curve 0 to time (AUC0→t) of BUD in the colon and kidney increased by approximately 32.35% and 39.03% respectively in the co-administered group compared to the single-drug group, while the small intestine, liver and plasma decreased by 80.03%, 67.34% and 24.34% respectively compared to the single-drug group. Therefore, long-term treatment with CUR can increase the concentration of BUD in the colonic area without increasing its systemic exposure, thus potentially reducing the incidence of side effects.

Understanding Discordance between In Vitro Dissolution, Local Gut and Systemic Bioequivalence of Budesonide in Healthy and Crohn's Disease Patients through PBPK Modeling

The most common method for establishing bioequivalence (BE) is to demonstrate similarity of concentration-time profiles in the systemic circulation, as a surrogate to the site of action. However, similarity of profiles from two formulations in the systemic circulation does not imply similarity in the gastrointestinal tract (GIT) nor local BE. We have explored the concordance of BE conclusions for a set of hypothetical formulations based on budesonide concentration profiles in various segments of gut vs. those in systemic circulation using virtual trials powered by physiologically based pharmacokinetic (PBPK) models. The impact of Crohn's disease on the BE conclusions was explored by changing physiological and biological GIT attributes. Substantial 'discordance' between local and systemic outcomes of VBE was observed. Upper GIT segments were much more sensitive to formulation changes than systemic circulation, where the latter led to false conclusions for BE. The ileum and colon showed a lower frequency of discordance. In the case of Crohn's disease, a product-specific similarity factor might be needed for products such as Entocort® EC to ensure local BE. Our results are specific to budesonide, but we demonstrate potential discordances between the local gut vs. systemic BE for the first time.

Altered Bioavailability and Pharmacokinetics in Crohn's Disease: Capturing Systems Parameters for PBPK to Assist with Predicting the Fate of Orally Administered Drugs

Backgrond and Objective

Crohn’s disease (CD) is a chronic inflammatory bowel disease that affects a wide age range. Hence, CD patients receive a variety of drugs over their life beyond those used for CD itself. The changes to the integrity of the intestine and its drug metabolising enzymes and transporters (DMETs) can alter the oral bioavailability of drugs. However, there are other changes in systems parameters determining the fate of drugs in CD, and understanding these is essential for dose adjustment in patients with CD.

Methods

The current analysis gathered all the available clinical data on the kinetics of drugs in CD (by March 2021), focusing on orally administered small molecule drugs. A meta-analysis of the systems parameters affecting oral drug pharmacokinetics was conducted. The systems information gathered on intestine, liver and blood proteins and other physiological parameters was incorporated into a physiologically based pharmacokinetic (PBPK) platform to create a virtual population of CD patients, with a view for guiding dose adjustment in the absence of clinical data in CD.

Results

There were no uniform trends in the reported changes in reported oral bioavailability. The nature of the drug as well as the formulation affected the direction and magnitude of variation in kinetics in CD patients relative to healthy volunteers. Even for the same drug, the reported changes in exposure varied, possibly due to a lack of distinction between the activity states of CD. The highest alteration was seen with S-verapamil and midazolam, 8.7- and 5.3-fold greater exposure, respectively, in active CD patients relative to healthy volunteers. Only one report was available on liver DMETs in CD, and indicated reduced CYP3A4 activity. In a number of reports, mRNA expression of DMETs in the ileum and colon of CD patients was measured, focussing on P-glycoprotein (p-gp) transporter and CYP3A4 enzyme, and showed contradictory results. No data were available on protein expression in duodenum and jejunum despite their dominant role in oral drug absorption.

Conclusion

There are currently inadequate dedicated clinical or quantitative proteomic studies in CD to enable predictive PBPK models with high confidence and adequate verification. The PBPK models for CD with the available systems parameters were able to capture the major physiological influencers and the gaps to be filled by future research. Quantification of DMETs in the intestine and the liver in CD is warranted, alongside well-defined clinical drug disposition studies with a number of index drugs as biomarkers of changes in DMETs in these patients, to avoid large-scale dedicated studies for every drug to determine the effects of disease on the drug’s metabolism and disposition and the consequential safety and therapeutic concerns.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40262-022-01169-4.

Does Food Affect the Pharmacokinetics of Non-orally Delivered Drugs? A Review of Currently Available Evidence

The food effects for orally administered drugs have been widely investigated and reviewed. In contrast, our knowledge of food effects for non-orally administered drugs is scarce. In this review paper, we did a literature survey to collect clinical food effect data for non-orally administered drugs. Our survey retrieved 18 drugs, including thirteen intravenously (IV), two subcutaneously (SC), one intradermally (ID), one pulmonary, and one rectally administered drug. The food effect data show that food intake can increase the absorption of SC and ID administered peptides and proteins with MW < 30 kDa by 30-50%. On the other hand, food intake can increase the elimination of IV and inhaled drugs with moderate and high hepatic extraction and reduce drug exposure by up to 35%. The food effect knowledge can be used to mitigate potential efficacy and safety risks of non-orally administered drugs.

Guidelines for the management of patients with Crohn's disease. Recommendations of the Polish Society of Gastroenterology and the Polish National Consultant in Gastroenterology

This paper is an update of the diagnostic and therapeutic recommendations of the National Consultant for Gastroenterology and the Polish Society of Gastroenterology from 2012. It contains 46 recommendations for the diagnosis and treatment, both pharmacological and surgical, of Crohn's disease in adults. The guidelines were developed by a group of experts appointed by the Polish Society of Gastroenterology and the National Consultant in the field of Gastroenterology. The methodology related to the GRADE methodology was used to assess the quality and strength of the available recommendations. The degree of expert support for the proposed statement, assessment of the quality of evidence and the strength of the recommendation was assessed on a 6-point Likert scale. Voting results, quality and strength ratings with comments are included with each statement.

Predicting budesonide performance in healthy subjects and patients with Crohn's disease using biorelevant in vitro dissolution testing and PBPK modeling

OBJECTIVES

Drug product performance might be affected in Crohn's disease (CD) patients compared to healthy subjects due to pathophysiological changes. Since a low number of clinical studies is performed in this patient population, physiologically-based pharmacokinetic (PBPK) models with integrated results from biorelevant in vitro dissolution studies could be used to assess differences in the bioavailability of drugs. Using this approach, budesonide was used as model drug and its performance in healthy subjects and CD patients was predicted and compared against observed pharmacokinetic data. The in vitro release tests, under healthy versus CD conditions, revealed a similar extent of drug release from a controlled-release budesonide formulation in the fasted state, whereas in the fed state a lower extent was observed with CD. Differences in the physiology of CD patients were identified in literature and their impact on budesonide performance was investigated with a PBPK model, revealing the highest impact on the simulated bioavailability for the reduced hepatic CYP3A4 enzyme abundance and lower human serum albumin concentration. For CD patients, a higher budesonide exposure compared to healthy subjects was predicted with a PBPK population adapted to CD physiology and in agreement with observed pharmacokinetic data. Budesonide performance in the fasted and fed state was successfully predicted in healthy subjects and CD patients using PBPK modeling and in vitro release testing. Following this approach, predictions of the direction and magnitude of changes in bioavailability due to CD could be made for other drugs and guide prescribers to adjust dosage regimens for CD patients accordingly.

Eosinophilic Gastroenteritis-associated Duodenal Ulcer Successfully Treated with Crushed Budesonide

Eosinophilic gastroenteritis (EGE)-associated duodenal ulcer is rare and its endoscopic and pathological features remain poorly described. A 15-year-old boy was referred to our hospital for further examination and treatment of duodenal ulcer. Esophagogastroduodenoscopy (EGD) revealed two A2-stage duodenal ulcers on the duodenal bulb. A biopsy revealed marked infiltration of eosinophils, suggestive of EGE-associated duodenal ulcers. Thus, treatment with crushed budesonide (9 mg/day) was started. EGD revealed healing of the duodenal ulcers seven months after treatment. To our knowledge, this is the first report describing EGE-associated duodenal ulcer successfully treated with crushed budesonide.

CYP3A4 Activity is Markedly Lower in Patients with Crohn's Disease

BACKGROUND

Disease-dependent changes in the activity of drug metabolizing enzymes and transporters, such as Cytochrome P450 (CYP) 3A4 and P-glycoprotein (P-gp), are thought to have a major influence on the disposition of shared substrates. However, little is known regarding the in vivo relevance of these 2 proteins during drug therapy for gastrointestinal diseases. Our aim was to elucidate the activity of CYP3A4 and P-gp in subjects with Crohn's disease (CD) and to evaluate their influence on budesonide pharmacokinetics.

METHODS

A detailed pharmacokinetic assessment was conducted in 8 individuals diagnosed with CD on stable doses of oral budesonide, a putative shared CYP3A4, and P-gp substrate, where hepatic and intestinal CYP3A4 activity were also assessed using intravenous and oral midazolam. In addition, oral fexofenadine was used as an in vivo probe for P-gp activity.

RESULTS

Budesonide area under the curve was highly variable between subjects but similar to previously reported values in healthy subjects. The hepatic and intestinal extraction ratios for midazolam were 0.11 ± 0.06 and 0.64 ± 0.25, respectively; however, CYP3A4 activity was nearly 5-fold lower in our CD cohort compared with published data among healthy subjects. Multivariate regression revealed that only 25% budesonide clearance could be explained based on midazolam or fexofenadine clearance.

CONCLUSIONS

Midazolam and fexofenadine disposition profile did not predict budesonide clearance. However, we observed a marked reduction in vivo CYP3A4 activity among individuals with CD. Therefore, changes in CYP3A4 activity in disease states such as CD may be a heretofore underappreciated determinant of variation in drug responsiveness in CD.

Budesonide Multi-matrix for the Treatment of Patients with Ulcerative Colitis

Ulcerative colitis (UC) is a chronic idiopathic inflammatory disorder in which patients cycle between active disease and remission. Budesonide multi-matrix (MMX) is an oral second-generation corticosteroid designed to deliver active drug throughout the colon. In pharmacokinetic studies, the mean relative absorption of budesonide in the region between the ascending colon and the descending/sigmoid colon was 95.9 %. In 2 identically designed, phase 3 studies (CORE I and II), budesonide MMX 9 mg once daily was efficacious and well tolerated for induction of remission of mild to moderate UC. Clinical and endoscopic remission rates were 17.9 % (CORE I) and 17.4 % (CORE II) for budesonide MMX 9 mg compared with 7.4 and 4.5 %, respectively, with placebo (p < 0.05, budesonide MMX 9 mg vs. placebo in both studies), 12.1 % with mesalamine 2.4 g, and 12.6 % with budesonide controlled ileal release capsules 9 mg. A 12-month maintenance therapy study suggested that budesonide MMX 6 mg may prolong time to clinical relapse: Median time was >1 year with budesonide MMX 6 mg versus 181 days (p = 0.02) with placebo; however, further studies are needed. In the CORE studies, budesonide MMX exhibited a favorable safety profile; the majority of adverse events were mild or moderate in intensity, and serious adverse events were uncommon. Furthermore, rates of potential glucocorticoid-related adverse events were comparable across treatment groups. The long-term (12-month) safety of budesonide MMX appears to be comparable with placebo. Data support budesonide MMX in the management algorithm of UC.

Integrated pharmacokinetics and pharmacodynamics of epoprostenol in healthy subjects

AIM

The aim of the study was to report the first thorough characterization of the pharmacokinetics (PK) and pharmacodynamics (PD) of epoprostenol in an integrated manner.

METHOD

Twenty healthy male subjects received two formulations of i.v. epoprostenol, in a crossover design, in sequential infusions of 2, 4, 6 and 8 ng kg(-1)  min(-1) for 2 h each. A sensitive assay was developed which allowed accurate PK characterization of epoprostenol via analysis of the concentration-time profiles of its two primary metabolites, 6-keto-prostacyclin F(1α) and 6,15-diketo-13,14-dihydro-prostacyclin F(1α) . PD parameters included cardiac output (CO), cardiac index (CIn) and heart rate (HR).

RESULTS

The pharmacokinetics of epoprostenol deviated slightly from dose-proportionality, probably due to a food effect. After infusion of the two formulations of epoprostenol, the t(1/2) values expressed as geometric mean (95% confidence interval) were 0.25 h (0.14, 0.46) and 0.22 h (0.13, 0.38) for 6-keto-prostacyclin F(1α) , and 0.32 h (0.22, 0.45) and 0.34 h (0.26, 0.46) for 6,15-diketo-13,14-dihydro-prostacyclin F(1α) . A single compartment infusion model with first order elimination adequately described the PK of 6-keto-prostacyclin F(1α) . This model also characterized the food effect. Stepwise infusions with epoprostenol resulted in a progressive increase in CO, CIn and HR.

CONCLUSION

Of the two metabolites analyzed, the appearance of 6-keto-prostacyclin F(1α) in plasma was more closely associated with the haemodynamic effects of i.v. epoprostenol. PK and PD profiles showed that CIn relates proportionally and linearly to the plasma concentrations of 6-keto-prostacyclin F(1α) . These results suggest that 6-keto-prostacyclin F(1α) is a suitable surrogate marker of plasma concentrations of epoprostenol.

Budesonide in the treatment of inflammatory bowel disease

Inflammatory bowel disease, including Crohn's disease and ulcerative colitis, features recurrent episodes of inflammation of the GI tract. The treatment of inflammatory bowel disease is aimed at breaking the cycle of relapsing and remitting inflammation by inducing and maintaining remission. Systemically active conventional corticosteroids have long played a role in the induction of remission in both Crohn's disease and ulcerative colitis, however, their long-term use can lead to adverse systemic effects. Budesonide, a synthetic steroid, has potent local anti-inflammatory effects and limited systemic bioavailability making it an appealing therapeutic option. Ulcerative colitis with predominantly distal disease may be treated with topical budesonide, however, novel oral controlled-release formulations have also been developed to allow for treatment of the entire colon. This article summarizes the use of budesonide in the management of inflammatory bowel disease.

Clinical trial: Preliminary efficacy and safety study of a new Budesonide-MMX® 9 mg extended-release tablets in patients with active left-sided ulcerative colitis

BACKGROUND

Ulcerative colitis (UC) is a chronic inflammatory disease with relapses. Many patients need systemic corticosteroids to induce clinical remission.

AIM

Efficacy and safety of Budesonide-MMX® 9 mg tablets, a new oral, extended-release formulation, were evaluated in patients suffering from active, left-sided UC with colitis activity index (CAI) <14.

METHODS

36 patients were treated once daily for 4 weeks with Budesonide-MMX® 9 mg tablets or placebo. In an additional 4-week period, all patients received Budesonide-MMX®. CAI, endoscopic index and histology were assessed after 4 and 8 weeks. Primary end-point was remission, and/or CAI reduction by 50% after 4 weeks. Morning cortisol was assayed after 4 and 8 weeks, and a short ACTH-test was performed at week 8.

RESULTS

32 patients were analysed. After 4 weeks, 47.1% of the patients in the Budesonide-MMX® 9 mg tablets group achieved the primary end-point vs. 33.3% of patients on placebo. In addition, 47.1% of budesonide patients and another 33.3% of placebo recipients improved without remission by 4 weeks. The CAI reduction was significant with Budesonide (p<0.0001) tablets and not with placebo (p=0.1). Neither morning cortisol nor pituitary-adrenal axis was more frequently suppressed with Budesonide tablets than with placebo.

CONCLUSIONS

Budesonide-MMX® 9 mg tablets induced a fast and significant clinical improvement of active left-sided UC without suppression of adrenocortical functions and without important toxicity EudraCT number 2004-000896-33.

Efficacy of budesonide therapy in the early phase of treatment of adult coeliac disease patients with malabsorption: an in vivo/in vitro pilot study

1. Budesonide is a glucocorticosteroid with a local anti-inflammatory effect. Coeliac disease is an immune-mediated disease caused by gluten ingestion in intolerant patients. The aim of the present study was to investigate the efficacy of budesonide in malabsorptive coeliac patients and its effect in an in vitro gliadin challenge. 2. Twenty coeliac patients with malabsorption were enrolled in the present study and were randomly assigned to one of two 4 week treatments: (i) a gluten-free diet alone; or (ii) a gluten-free diet plus 6 mg budesonide daily. At the end of 4 weeks treatment, all patients underwent clinical evaluation, laboratory tests and self-evaluation of well-being using a visual analogue scale. Intestinal biopsies from five coeliac patients (selected randomly) and four non-coeliac disease controls who underwent upper endoscopy for intestinal bleeding were challenged with gliadin (0.5 mg/mL) and budesonide (10-30 microg/mL) for 3 and 24 h. Biopsies were tested by immunohistochemistry and immunofluorescence for known markers of inflammation. 3. Treatment of patients with 6 mg budesonide daily for 4 weeks resulted in increased bodyweight, a decreased number of evacuations and decreased stool weight compared with patients on a gluten-free diet alone for 4 weeks. Well-being scores were higher in patients treated with both a gluten-free diet and budesonide compared with those receiving a gluten-free diet alone. 4. In vitro studies showed that budesonide reduced epithelial tyrosine phosphorylation and expression of histocompatibility leucocyte antigen complex DR (HLA-DR) elicited by gliadin-derived peptides. In addition, the expression of cyclo-oxygenase (COX)-2 and intercellular adhesion molecule (ICAM)-1 in the lamina propria was reduced in patients treated with both gliadin and budesonide compared with patients treated with gliadin alone. Budesonide alone decreased HLA-DR in crypt enterocytes, as well as ICAM-1 and COX-2 expression in the lamina propria of biopsy specimen of coeliac patients. Budesonide had no effect in control samples. 5. In conclusion, the results of the present study indicate that budesonide shows efficacy in the treatment of symptoms in adult coeliac patients with overt malabsorption. The mechanism underlying the effects of budesonide in reducing symptoms was elucidated by in vitro studies involving a gliadin challenge.

Gastrointestinal transit, release and plasma pharmacokinetics of a new oral budesonide formulation

AIMS

The aims of the study were to: (1) evaluate the gastrointestinal transit, release and absorption of budesonide from tablets with a new multimatrix formulation (MMX) designed to release the drug throughout the whole colon, and (2) assess the influence of food on budesonide bioavailability.

METHODS

Two phase I studies, each comprising 12 healthy males, were performed. Gastrointestinal transit of (153)Sm-labelled tablets containing 9 mg budesonide was evaluated by means of pharmaco-scintigraphy. The effect of food was tested by comparing plasma pharmacokinetics after intake of a high fat and high calorie breakfast with fasting controls.

RESULTS

(153)Sm-labelled tablets reached the ascending colon after a mean +/- SD 9.8 +/- 6.9 h. Initial tablet disintegration was observed in the ileum in 42% and the ascending and transverse colon in 33% of subjects. Ninety-six per cent of the dose was absorbed into the systemic circulation during passage through the whole colon including the sigmoid. Food significantly decreased C(max) values from 1429 +/- 1014 to 1040 +/- 601 pg mL(-1) (P = 0.028) and AUC values from 14 814 +/- 11 254 to 13 486 +/- 9369 pg h(-1) mL(-1) (P = 0.008). Mean residence time and t(max) increased by 12-29%. There was no drug accumulation after 1 week of once daily oral administration of budesomide.

CONCLUSIONS

MMX-budesonide tablets appear suitable for targeted colonic drug delivery. Transit parameters and low systemic bioavailability warrant further studies with the new formulation.

Budesonide for induction of remission in Crohn's disease

BACKGROUND

Corticosteroids continue to play a central role in induction of remission in active Crohn's disease. However, their use comes at a price of significant adverse effects when used repeatedly or for extended periods. Newer corticosteroid agents with limited systemic bioavailability offer a tantalizing option, if they can be shown to be efficacious and safer than conventional corticosteroids. Budesonide is the main alternative corticosteroid currently available in an enteric formulation.

OBJECTIVES

To evaluate the effectiveness of oral budesonide for the treatment of acute flares of Crohn's disease. A secondary but important endpoint was to evaluate the adverse effect profile.

SEARCH STRATEGY

The following sources were used to search the literature for potentially relevant papers and trials. 1. A computer-assisted search of the on-line bibliographic database MEDLINE from 1986 onwards. 2. Hand searching the reference lists of trials and review articles identified by means of the computer- assisted search. 3. Proceedings from major gastrointestinal meetings were manually searched from 1990 onwards. 4. Contact with the relevant pharmaceutical companies that have been involved in the development of budesonide.

SELECTION CRITERIA

Potentially relevant articles were reviewed in an independent unblinded fashion by two authors to determine if they met the criteria specified below: 1) STUDY POPULATION: Patients of any age with acutely active Crohn's disease, as defined by a CDAI > 150. 2) METHODOLOGY: Randomized double blind controlled trials comparing budesonide to a control treatment. Patients in the control arm may have received placebo, conventional corticosteroids, 5-aminosalicylic acid or sulfasalazine. 3) OUTCOME MEASURES: Clinical remission was the outcome measure of interest. The definition of remission was usually a CDAI < 150 by 8 to 16 weeks of therapy.

DATA COLLECTION AND ANALYSIS

Eligible articles were reviewed in duplicate and the results of the primary research trials were abstracted onto specially designed data extraction forms. The proportion of patients achieving remission in the active treatment and control groups of each study were derived from the data provided in the original research papers. Where possible, data were broken down based on site of disease or other strata used by the individual trials.

STATISTICAL ANALYSIS

Data extracted from the original research articles were converted, where necessary, into individual 2 x 2 tables (remission versus no remission x budesonide versus control) for each of the individual studies. Where available, individual 2 x 2 tables for strata within studies were also used. The presence of significant heterogeneity among studies was tested for using the chi-square test. Because this is a relatively insensitive test for the presence of heterogeneity, a p-value of 0.10 was regarded as statistically significant. Where p < 0.10 the data from the individual studies were still combined but the pooled results were interpreted with caution. The 2 x 2 tables were synthesized into a summary test statistic using the pooled odds ratio and 95% confidence intervals as described by Cochran and Mantel and Haenszel. A fixed effects model was used for the pooling of data. The analysis was performed initially by combining data from all trials to estimate the response rate to budesonide therapy. The analysis was also performed by combining only studies with comparable control groups.

MAIN RESULTS

Eight studies were deemed eligible for review.

EFFICACY

Budesonide was superior to placebo for induction of remission with a pooled odds ratio for the two placebo-controlled trials of 2.85 (95% CI 1.67 - 4.87). A single trial comparing budesonide with mesalamine demonstrated an odds ratio of 2.80 (95% CI 1.50 - 5.20) in favour of budesonide over mesalamine for induction of remission in active Crohn's disease. However, budesonide was inferior to conventional corticosteroids (prednisone or prednisolone) for induction of remission with a pooled odds ratio for the five trials of 0.69 (95% CI 0.51 - 0.95).

SAFETY

The two trials comparing budesonide versus placebo (Greenberg 1994; Tremaine 2002) showed no difference between study groups for proportion of reported corticosteroid-related adverse effects with the pooled odds ratio for both trials of 0.98 (95% CI 0.58 - 1.67). Five trials comparing budesonide versus prednisone showed the budesonide study group had fewer reported corticosteroid-related adverse effects than the prednisone study group (pooled odds ratio was 0.38 (95% CI 0.28 - 0.53).

AUTHORS' CONCLUSIONS

With disease in the ileum or ascending colon, budesonide offers an effective therapy which is somewhat less efficacious but with fewer adverse effects than conventional corticosteroids (e.g. prednisone, prednisolone, or 6-methylprednisolone).

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.

Pharmacokinetics of budesonide (Entocort EC) capsules for Crohn's disease

This overview summarises available pharmacokinetic data on budesonide capsules (Entocort EC), approved for the treatment of mild-to-moderate active Crohn's disease involving the ileum and/or ascending colon and for prolongation of symptom control. Budesonide is a locally-acting glucocorticosteroid with an extensive, primarily hepatic, metabolism after oral administration. It is rapidly absorbed and biotransformed by cytochrome P450 (CYP) 3A to metabolites with negligible glucocorticoid activity. Entocort EC, a pH- and time-dependent oral formulation of budesonide, was developed to optimise drug delivery to the ileum and throughout the colon. Pharmaco-scintigraphic studies have confirmed that the Entocort EC formulation delays budesonide absorption and prolongs the rate of elimination but maintains complete absorption. This improves the delivery of budesonide to the intestinal lumen relative to a plain formulation. A low systemic availability of 9-21% indicates extensive first-pass elimination. Food appears to have little impact on the absorption of budesonide from Entocort EC capsules and the pharmacokinetics are dose-proportional between 3 and 15 mg. On average, systemic availability was 2.5-fold higher in patients with cirrhosis compared with healthy controls; however, mild liver impairment had little effect on systemic exposure. Pharmacokinetics appear unaffected by gender and age, although this has not been tested in younger children. Renal impairment is not expected to have an impact on the kinetics of Entocort EC. Budesonide is unlikely to inhibit the metabolism of other drugs, including CYP3A4 substrates, mainly because of the very low plasma concentrations obtained with the compound even after high doses of Entocort trade mark EC capsules. Strong CYP3A4 inhibitors, such as ketoconazole, will inhibit the metabolism of budesonide, resulting in several-fold increases in the area under the concentration-time curve of budesonide. Also, grapefruit juice intake may increase systemic availability of budesonide, probably by inhibition of intestinal CYP3A4 activity. Unlike prednisolone, oral contraceptives do not alter plasma budesonide concentrations. An increased pH obtained by gastric acid inhibitory drugs, such as omeprazole, does not affect the pharmacokinetics of budesonide. In summary, budesonide capsules (Entocort EC) possess many pharmacological features that make the formulation well adapted for a targeted treatment of inflammatory disorders, such as Crohn's disease involving the ileum and ascending colon.

Targeted delivery, safety, and efficacy of oral enteric-coated formulations of budesonide

Budesonide is a potent corticosteroid with a high first-pass metabolism rate. Two commercially available enteric-coated pH-dependent release formulations (Entocort EC and Budenofalk) deliver budesonide to the ileum and proximal colon, regions most commonly affected in Crohn's disease. The drug's effectiveness in this disease has been proven in multiple, placebo-controlled trials, where it has been shown to be superior to mesalamine and placebo, and equivalent to prednisolone for the control of mild to moderately active right-sided Crohn's disease. This beneficial therapeutic effect comes with less adrenal suppression and a small improvement in the clinical adverse effect profile, as compared to prednisolone. However, budesonide provides no benefit over conventional therapy for left-sided colonic disease, and it is less effective for treatment of more severe disease activity and more distal colonic disease. Continuous budesonide does not prolong remission and is, therefore, best used in an intermittent fashion to treat acute exacerbations.

Topical delivery of therapeutic agents in the treatment of inflammatory bowel disease

For targeting local and systemic inflammatory processes in inflammatory bowel disease (IBD) therapeutic agents of first choice (e.g. aminosalicylates, corticosteroids) have been developed in special galenic forms to accomplish the topical delivery of the active compounds to the terminal ileum (Crohn's disease) and/or the colon (Crohn's disease and ulcerative colitis). However, it has to be realized that intestinal physiology (e.g. motility, intraluminal pH profiles), extent and pattern of IBD as well as drug disposition demonstrate large interindividual differences resulting in variable clinical response rates between about 35% and 75%. 5-Aminosalicylate (5-AS) can be delivered to the colon either by azo-prodrugs (e.g. sulfasalazine, olsalazine or balsalazide) or by direct rectal administration of 5-AS in form of enemas, foam or suppositories. Such formulations will be only effective in patients with ulcerative colitis (UC). Various slow/controlled release preparations of 5-AS have been developed for oral use. Some of them (e.g. Pentasa, Salofalk) release sufficient 5-AS already in the small bowel which could provide some additional benefit in Crohn's disease (CD). As urinary and faecal recoveries of total 5-AS are similar for all oral formulations, no major clinical differences can be expected. Extent of the disease, profile of adverse effects and patient's acceptance provide some guidance for selection of the particular agent. Rectal installation of several glucocorticosteroids has been employed for many years. More recently scientific and clinical interest has been focused on budesonide which is extensively presystemically metabolized in the intestinal wall and the liver. Therefore, its systemic availability is low (10-15%) independent whether budesonide is administered orally as controlled release formulation in patients with CD or rectally as enema in patients with UC. Numerous pharmacokinetic and clinical studies have documented the anticipated topical delivery and clinical efficacy of this corticosteroid without serious side effects such as cushingoid features. It can be assumed that for any novel therapeutic principle in IBD the approach of topical delivery will be also tried.

Oral Budesonide in the Management of Crohn's Disease

OBJECTIVE

To review the pharmacology, pharmacokinetics, efficacy, and safety of oral budesonide (Entocort EC) in the treatment of mild to moderate Crohn's disease (CD).

DATA SOURCES

The MEDLINE database (1966-December 2002) was searched using the key words budesonide and inflammatory bowel diseases and restricted to the English language. The references from relevant articles were also reviewed for additional citations.

STUDY SELECTION AND DATA EXTRACTION

Articles and abstracts that evaluated oral budesonide for management of CD were considered, with emphasis on randomized, controlled clinical trials.

DATA SYNTHESIS

Budesonide's high potency at the glucocorticoid receptor and extensive first-pass hepatic metabolism result in a topical antiinflammatory effect on intestinal tissue, with minimal systemic glucocorticoid adverse effects. Clinical trials have demonstrated that budesonide is effective in the treatment of patients with mild to moderate CD of the ileum and ascending colon, with efficacy similar to prednisolone and superior to mesalamine. Long-term therapy with budesonide increased the duration of CD remission, but the effect was not sustained up to 1 year. Budesonide failed to prevent postsurgical relapse of CD. Adrenal suppression and glucocorticoid-related adverse effects have been reported at lower rates in patients treated with budesonide compared with prednisolone. Patients prescribed budesonide should be monitored for hepatic dysfunction and potential drug interactions.

CONCLUSIONS

Budesonide is an effective and relatively safe option for treatment of mild to moderate CD of the ileum and ascending colon.

Budesonide (Entocort EC Capsules): a review of its therapeutic use in the management of active Crohn's disease in adults

Budesonide (Entocort EC Capsules) is an oral corticosteroid with a high degree of topical activity and low systemic bioavailability (approximately 11%). This action is achieved by a high affinity for the glucocorticoid receptor and an extensive first-pass hepatic metabolism. The budesonide capsule has been formulated to dissolve in a pH dependent manner, delivering most of the drug to the ileum and ascending colon, areas of the intestine most commonly affected by Crohn's disease. In large (n > or = 176), well designed clinical trials of 10 to 12 weeks' duration in patients with active, mild to moderate Crohn's disease, budesonide (9 mg/day) was significantly more effective in inducing remission than placebo or mesalazine (mesalamine) slow release, and demonstrated similar efficacy to recommended dosages of prednisolone. Results of health-related quality-of-life assessments support clinical data, showing a significantly greater improvement among patients treated with budesonide than with placebo or mesalazine slow release. Oral budesonide was well tolerated in clinical trials of up to 16 weeks' duration. In these studies, the incidence of adverse events associated with budesonide (9 mg/day) was similar to that seen with placebo and mesalazine slow release. The rate of glucocorticoid-related adverse effects observed with budesonide was significantly less than that reported with prednisolone.

CONCLUSION

Oral budesonide 9 mg/day offers efficacy that is superior to mesalazine slow release and placebo, and similar to prednisolone in the treatment of patients with active mild to moderate Crohn's disease involving the ileum and/or ascending colon. Budesonide is generally well tolerated and the incidence of adverse events is similar to that seen with placebo or mesalazine slow release. Glucocorticoid-related adverse effects are significantly less frequent during short-term therapy with budesonide than with prednisolone. Thus, for the medical management of patients with active mild to moderate Crohn's disease, oral budesonide has superior efficacy to mesalazine slow release and a more favourable tolerability profile than prednisolone.

A pharmacoscintigraphic evaluation of oral budesonide given as controlled-release (Entocort) capsules

AIMS

To investigate the gastrointestinal pharmacokinetics of controlled-release (Entocort) and standard budesonide capsules.

METHODS

Six Crohn's disease patients and eight healthy controls were given controlled-release capsules containing budesonide and an inert 111In label, following breakfast. In the patients, a standard capsule containing deuterium-labelled budesonide was given simultaneously. In the controls, on a separate occasion, the controlled-release capsules were given in the fasting state. Gastrointestinal transit was recorded by a gamma camera. Plasma budesonide and deuterium-labelled budesonide were used to estimate drug release, and urine cortisol was used to assess systemic effects.

RESULTS

Budesonide delivery to the ileo-colonic region was significantly greater after the intake of the controlled-release capsules [69%; 95% confidence interval (CI), 54-84] than after the standard capsules (30%; 95% CI, 15-45) (P = 0.005). Fasting had little impact on uptake. The transit and pharmacokinetics of budesonide were similar in both subject groups, although systemic availability was higher in patients (21%; 95% CI, 13-33) than in controls (12%; 95% CI, 10-14) (P = 0.009). Urinary cortisol was, however, similar in both groups.

CONCLUSIONS

A major fraction of budesonide is released in the ileum and throughout the colon, the intended target for the controlled-release formulation. The prandial state has little effect on budesonide uptake.

Pharmacokinetics of budesonide controlled ileal release capsules in children and adults with active Crohn's disease

BACKGROUND

Systemic glucocorticosteroid therapy is effective in Crohn's disease, but is associated with side-effects. Budesonide has high topical anti-inflammatory activity, but considerably lower systemic activity than other oral glucocorticosteroids.

AIM

To evaluate the systemic exposure to budesonide (controlled ileal release capsules) in children and adults with active Crohn's disease, and to assess the suppression of plasma cortisol.

METHODS

In an open label study, patients (eight children and six adults) with active Crohn's disease received 9 mg budesonide (Entocort capsules) orally once daily for 7 days. Plasma concentrations were determined on the seventh day of administration, and pharmacokinetic parameters were calculated. For reference, 0.5 mg budesonide was given intravenously separately. Plasma cortisol levels were compared with the pre-treatment baseline values.

RESULTS

Systemic exposure to budesonide (AUC0-24 h) after 1 week of oral administration was 41 +/- 21 nmol/L x h (mean +/- s.d.) in children and 35 +/- 20 nmol/L x h in adults. The estimated systemic availability in children was 9 +/- 5% and in adults 11 +/- 7%. The mean plasma cortisol (AUC0-24 h) decreased by 64 +/- 18% in children and by 50 +/- 27% in adults.

CONCLUSIONS

The systemic exposure, systemic availability and cortisol suppression after oral administration of 9 mg budesonide were similar in children and adults with active Crohn's disease. Budesonide was well tolerated and no clinically important safety-related findings were identified.

Gut delivery of budesonide, a locally active corticosteroid, from plain and controlled-release capsules

OBJECTIVE

To compare the pharmacokinetics and site of uptake of budesonide from a controlled-release formulation and a deuterium-labelled standard formulation given before and after a meal.

METHODS

Six healthy volunteers were randomized into an open, crossover study. They received 4.5 mg controlled-release budesonide (mixed with In pellets to trace gastrointestinal transit) and 4.8 mg 2H8-budesonide simultaneously at each of two visits: one visit before a standardized breakfast and the other after breakfast. Plasma concentrations of budesonide were followed over 24 h. The transit of the (111)In pellets through the gastrointestinal tract was followed for 36 h. Data on the site of absorption were calculated from transit times and absorption curves.

RESULTS

The time to peak plasma concentration was significantly increased with controlled-release budesonide when compared with the deuterium-labelled standard formulation (before breakfast, 4.5 h vs 1.8 h; after breakfast, 5.2 h vs 2.9 h). When given after breakfast, the controlled-release formulation was associated with a mean residence time 1.6 h longer than that seen with the standard formulation. However, the areas under the plasma concentration curves were similar with the two formulations, regardless of when the treatments were given (before breakfast, 18.0 +/- 3.8 nmol/l vs 18.0 +/- 6.0 nmol/l; after breakfast, 16.9 +/- 7.0 nmol/l vs 18.5 +/- 9.0 nmol/l). Over 60% of the total budesonide absorbed from controlled-release capsules was delivered and absorbed in the ileum and colon. The corresponding proportion for the standard formulation was approximately 33%.

CONCLUSIONS

Controlled-release budesonide effectively delivers most of the budesonide dose to the ileum and colon, the regions that are most often affected by inflammatory bowel disease. In addition, the time of food intake has little effect on the site of absorption or the bioavailability of the controlled-release formulation. Delivery to the colon and ileum was independent of whether the drug was given before or after breakfast.

Budesonide fatty-acid esterification: a novel mechanism prolonging binding to airway tissue. Review of available data

AIMS

Evidence is accumulating that budesonide (BUD) forms intracellular esters in airways. which may affect both duration of action and therapeutic ratio of this drug. The aim of the present paper is to review the preclinical and human experimental evidence supporting the esterification of BUD, and to discuss the clinical implications this may have on asthma and rhinitis treatment.

RESULTS

After inhalation, intact BUD binds primarily to available steroid receptors, and mainly excess (unbound) BUD is esterified. Esterification of BUD is a rapid process: within 20 minutes of inhalation in the rat of radiolabeled BUD, approximately 80% of radioactivity within the trachea and main bronchi was associated with BUD esters, primarily BUD oleate. After 4 hours, the proportion of BUD esters/total cellular BUD was typically 40 to 50% for lung, 70 to 90% for trachea, and only 10 to 15% for peripheral muscle. Comparative in vitro and in vivo studies have shown that esterification prolongs BUD's anti-inflammatory activity longer than that of corticosteroids that can not form esters. Clinical studies have confirmed the prolonged presence of BUD esters, as well as intact BUD, in human airway tissues: 6 hours postdosing, nasal biopsy concentrations of intact BUD were >10-fold greater than those of fluticasone propionate and at 24 hours BUD was detectable in threefold more biopsies than fluticasone propionate. The impact of esterification on airway selectivity of BUD has also been demonstrated in vivo and using pharmacokinetic/pharmacodynamic models.

CONCLUSIONS

BUD is retained in airways as esters, a novel kinetic mechanism for synthetic glucocorticoids. In preclinical studies this esterification is correlated to a prolonged local tissue binding and efficacy, which is not found when the esterification is inhibited by an esterification blocker. Because less esters are formed in the systemic compartment than in airways/lung, the local benefit:systemic risk ratio may also be improved by this mechanism. BUD possesses favorable clinical properties, including its approved once-daily efficacy in asthma, which is probably in part attributable to esterification. However, a direct proof of the latter in patients requires effective and safe inhibitors of the esterification, which are not yet available. Therefore, evidence to support the therapeutic impact of esterification is still circumstantial.