Comparison of four pancreatic extracts in cystic fibrosis

Pancreatic enzyme replacement therapy for people with cystic fibrosis

BACKGROUND

Most people with cystic fibrosis (CF) (80% to 90%) need pancreatic enzyme replacement therapy (PERT) to prevent malnutrition. Enzyme preparations need to be taken whenever food is taken, and the dose needs to be adjusted according to the food consumed. A systematic review on the efficacy and safety of PERT is needed to guide clinical practice, as there is variability between centres with respect to assessment of pancreatic function, time of commencing treatment, dose and choice of supplements. This is an updated version of a published review.

OBJECTIVES

To evaluate the efficacy and safety of PERT in children and adults with CF and to compare the efficacy and safety of different formulations of PERT and their appropriateness in different age groups. Also, to compare the effects of PERT in CF according to different diagnostic subgroups (e.g. different ages at introduction of therapy and different categories of pancreatic function).

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register comprising references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings. Most recent search: 07 November 2019. We also searched an ongoing trials website and the websites of the pharmaceutical companies who manufacture pancreatic enzyme replacements for any additional trials. Most recent search: 26 December 2019.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials in people of any age, with CF and receiving PERT, at any dosage and in any formulation, for a period of not less than four weeks, compared to placebo or other PERT preparations.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trials and extracted outcome data. They also assessed the risk of bias and quality of the evidence (GRADE) of the trials included in the review.

MAIN RESULTS

14 trials were included in the review (641 children and adults with CF), two of these were parallel trials and 12 were cross-over trials. Interventions included different enteric and non-enteric-coated preparations of varying formulations in comparison to each other. The number of participants in each trial varied between 14 and 129. 13 trials were for a duration of four weeks and one trial lasted seven weeks. The majority of the trials had an unclear risk of bias from the randomisation process as the details of this were not given; they also had a high risk of attrition bias and reporting bias. The quality of the evidence ranged from moderate to very low. We mostly could not combine data from the trials as they compared different formulations and the findings from individual trials provided insufficient evidence to determine the size and precision of the effects of different formulations.

AUTHORS' CONCLUSIONS

There is limited evidence of benefit from enteric-coated microspheres when compared to non-enteric coated pancreatic enzyme preparations up to one month. In the only comparison where we could combine any data, the fact that these were cross-over trials is likely to underestimate the level of inconsistency between the results of the trials due to over-inflation of CIs from the individual trials.There is no evidence on the long-term effectiveness and risks associated with PERT. There is also no evidence on the relative dosages of enzymes needed for people with different levels of severity of pancreatic insufficiency, optimum time to start treatment and variations based on differences in meals and meal sizes. There is a need for a properly designed trial that can answer these questions.

Pancreatic enzyme replacement therapy for people with cystic fibrosis

BACKGROUND

Most people with cystic fibrosis (80% to 90%) need pancreatic enzyme replacement therapy to prevent malnutrition. Enzyme preparations need to be taken whenever food is taken, and the dose needs to be adjusted according to the food consumed. A systematic review on the efficacy and safety of pancreatic enzyme replacement therapy is needed to guide clinical practice, as there is variability between centres with respect to assessment of pancreatic function, time of commencing treatment, dose and choice of supplements. This is an updated version of a published review.

OBJECTIVES

To evaluate the efficacy and safety of pancreatic enzyme replacement therapy in children and adults with cystic fibrosis and to compare the efficacy and safety of different formulations of this therapy and their appropriateness in different age groups. Also, to compare the effects of pancreatic enzyme replacement therapy in cystic fibrosis according to different diagnostic subgroups (e.g. different ages at introduction of therapy and different categories of pancreatic function).

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register comprising references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings. Most recent search: 15 July 2016.We also searched an ongoing trials website and the websites of the pharmaceutical companies who manufacture pancreatic enzyme replacements for any additional trials. Most recent search: 22 July 2016.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials in people of any age, with cystic fibrosis and receiving pancreatic enzyme replacement therapy, at any dosage and in any formulation, for a period of not less than four weeks, compared to placebo or other pancreatic enzyme replacement therapy preparations.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trials and extracted outcome data. They also assessed the risk of bias of the trials included in the review.

MAIN RESULTS

One parallel trial and 12 cross-over trials of children and adults with cystic fibrosis were included in the review. The number of participants in each trial varied between 14 and 129 with a total of 512 participants included in the review. All the included trials were for a duration of four weeks. The included trials had mostly an unclear risk of bias from the randomisation process as the details of this were not given; they also mostly had a high risk of attrition bias and reporting bias.We could not combine data from all the trials as they compared different formulations. Findings from individual studies provided insufficient evidence to determine the size and precision of the effects of different formulations. Ten studies reported information on the review's primary outcome (nutritional status); however, we were only able to combine data from two small cross-over studies (n = 41). The estimated gain in body weight was imprecise, 0.32 kg (95% confidence interval -0.03 to 0.67; P = 0.07). Combined data from the same studies gave statistically significant results favouring enteric-coated microspheres over enteric-coated tablets for our secondary outcomes stool frequency, mean difference -0.58 (95% confidence interval -0.85 to -0.30; P < 0.0001); proportion of days with abdominal pain, mean difference -7.96% (95% confidence interval -12.97 to -2.94; P = 0.002); and fecal fat excretion, mean difference -11.79 g (95% confidence interval -17.42 to -6.15; P < 0.0001). Data from another single small cross-over study also favoured enteric-coated microspheres over non-enteric-coated tablets with adjuvant cimetidine in terms of stool frequency, mean difference -0.70 (95% confidence interval -0.90 to -0.50; P < 0.00001).

AUTHORS' CONCLUSIONS

There is limited evidence of benefit from enteric-coated microspheres when compared to non-enteric coated pancreatic enzyme preparations up to one month. In the only comparison where we could combine any data, the fact that these were cross-over studies is likely to underestimate the level of inconsistency between the results of the studies due to over-inflation of confidence intervals from the individual studies.There is no evidence on the long-term effectiveness and risks associated with pancreatic enzyme replacement therapy. There is also no evidence on the relative dosages of enzymes needed for people with different levels of severity of pancreatic insufficiency, optimum time to start treatment and variations based on differences in meals and meal sizes. There is a need for a properly designed study that can answer these questions.

Pancreatic enzyme replacement therapy for people with cystic fibrosis

BACKGROUND

Most people with cystic fibrosis (80% to 90%) need pancreatic enzyme replacement therapy to prevent malnutrition. Enzyme preparations need to be taken whenever food is taken, and the dose needs to be adjusted according to the food consumed. A systematic review on the efficacy and safety of pancreatic enzyme replacement therapy is needed to guide clinical practice, as there is variability between centres with respect to assessment of pancreatic function, time of commencing treatment, dose and choice of supplements.

OBJECTIVES

To evaluate the efficacy and safety of pancreatic enzyme replacement therapy in children and adults with cystic fibrosis and to compare the efficacy and safety of different formulations of this therapy and their appropriateness in different age groups. Also, to compare the effects of pancreatic enzyme replacement therapy in cystic fibrosis according to different diagnostic subgroups (e.g. different ages at introduction of therapy and different categories of pancreatic function).

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register comprising references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings. Most recent search: 14 August 2014.We also searched an ongoing trials website and the websites of the pharmaceutical companies who manufacture pancreatic enzyme replacements for any additional trials. Most recent search: 12 May 2014.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials in people of any age, with cystic fibrosis and receiving pancreatic enzyme replacement therapy, at any dosage and in any formulation, for a period of not less than four weeks, compared to placebo or other pancreatic enzyme replacement therapy preparations.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trials and extracted outcome data. They also assessed the risk of bias of the trials included in the review.

MAIN RESULTS

One parallel trial and 11 cross-over trials of children and adults with cystic fibrosis were included in the review. The number of participants in each trial varied between 14 and 129 with a total of 426 participants included in the review. All the included trials were for a duration of four weeks. The included trials had mostly an unclear risk of bias from the randomisation process as the details of this were not given; they also mostly had a high risk of attrition bias and reporting bias.We could not combine data from all the trials as they compared different formulations. Findings from individual studies provided insufficient evidence to determine the size and precision of the effects of different formulations. Ten studies reported information on the review's primary outcome (nutritional status); however, we were only able to combine data from two small cross-over studies (n = 41). The estimated gain in body weight was imprecise, 0.32 kg (95% confidence interval -0.03 to 0.67, P = 0.07). Combined data from the same studies gave statistically significant results favouring enteric-coated microspheres over enteric-coated tablets for our secondary outcomes stool frequency, abdominal pain and fecal fat excretion. Data from another single small cross-over study also favoured enteric-coated microspheres over non-enteric-coated tablets with adjuvant cimetidine in terms of stool frequency.

AUTHORS' CONCLUSIONS

There is limited evidence of benefit from enteric-coated microspheres when compared to non-enteric coated pancreatic enzyme preparations up to one month. In the only comparison where we could combine any data, the fact that these were cross-over studies is likely to underestimate the level of inconsistency between the results of the studies due to over-inflation of confidence intervals from the individual studies.There is no evidence on the long-term effectiveness and risks associated with pancreatic enzyme replacement therapy. There is also no evidence on the relative dosages of enzymes needed for people with different levels of severity of pancreatic insufficiency, optimum time to start treatment and variations based on differences in meals and meal sizes. There is a need for a properly designed trial that can answer these questions.

Pancreatic enzyme replacement therapy for pancreatic exocrine insufficiency in the 21st century

Restitution of normal fat absorption in exocrine pancreatic insufficiency remains an elusive goal. Although many patients achieve satisfactory clinical results with enzyme therapy, few experience normalization of fat absorption, and many, if not most, will require individualized therapy. Increasing the quantity of lipase administered rarely eliminates steatorrhea but increases the cost of therapy. Enteric coated enzyme microbead formulations tend to separate from nutrients in the stomach precluding coordinated emptying of enzymes and nutrients. Unprotected enzymes mix well and empty with nutrients but are inactivated at pH 4 or below. We describe approaches for improving the results of enzyme therapy including changing to, or adding, a different product, adding non-enteric coated enzymes, (e.g., giving unprotected enzymes at the start of the meal and acid-protected formulations later), use of antisecretory drugs and/or antacids, and changing the timing of enzyme administration. Because considerable lipid is emptied in the first postprandial hour, it is prudent to start therapy with enteric coated microbead prior to the meal so that some enzymes are available during that first hour. Patients with hyperacidity may benefit from adjuvant antisecretory therapy to reduce the duodenal acid load and possibly also sodium bicarbonate to prevent duodenal acidity. Comparative studies of clinical effectiveness of different formulations as well as the characteristics of dispersion, emptying, and dissolution of enteric-coated microspheres of different diameter and density are needed; many such studies have been completed but not yet made public. We discuss the history of pancreatic enzyme therapy and describe current use of modern preparations, approaches to overcoming unsatisfactory clinical responses, as well as studies needed to be able to provide reliably effective therapy.

Efficacy and safety of PANCREAZE® for treatment of exocrine pancreatic insufficiency due to cystic fibrosis

BACKGROUND

Pancreatic enzyme replacement therapy (PERT) is critical for correction of exocrine pancreatic insufficiency (EPI) in patients with cystic fibrosis (CF).

METHODS

This was a randomized, placebo-controlled PERT withdrawal study evaluating the efficacy and safety of PANCREAZE® (pancrelipase) in CF patients with EPI. Participants (n=49) entered an open-label, ≤ 14 day run-in phase, maintained a high-fat diet (100 ± 15 g/day), and received PANCREAZE® (10.5 or 21). Participants with a coefficient of fat absorption (CFA)≥ 80% (n=40) were then randomized (1:1) to receive either PANCREAZE® or placebo during a double-blind, ≤ 7 day withdrawal phase.

RESULTS

PANCREAZE® improved fat absorption as shown by significantly lower mean ± SD change in CFA between open-label and double-blind phases for PANCREAZE® (-1.5 ± 5.88%; p<0.001) compared to placebo (-34.1 ± 23.03%). Protein absorption was similarly improved. No unexpected adverse events were reported.

CONCLUSIONS

This study demonstrated PANCREAZE® was effective in treating EPI due to CF and was safe and well tolerated.

Gastric emptying of multi-particulate dosage forms

The evidence in the literature for the concept that multi-particulate dosage forms below a specific size empty from the stomach as if they were liquids and hence have the potential to provide the best solution to the formulation of controlled release oral dosage forms, has been considered. There is some evidence that particles less than 1.0mm provide a more rapid response than larger size particles but there is also evidence that this is not always the case and that rapid and reproducible gastric emptying of small particles does not always occur when they are administered. There is strong evidence that food can delay the gastric emptying of multi-particulate systems. Some of the misconception for gastric emptying performance of multi-particulate system is shown to be related to the limitation of the study design and limitation of the way the data is processed. Nevertheless, there is clear evidence that multi-particulate systems can provide effective oral controlled release dosage forms. There is still some way to go with experimental techniques which would allow a definitive answer to the issue of how the variability of the gastric emptying of multi-particulate systems of less than 2.0mm arises.

Systematic review: efficacy and safety of pancreatic enzyme supplements for exocrine pancreatic insufficiency

BACKGROUND

Pancreatic enzyme supplements are standard therapy for fat malabsorption in patients with exocrine pancreatic insufficiency. The FDA determined that published data are insufficient to support the efficacy and safety of these agents.

AIM

To determine if pancreatic enzyme supplements are: (i) superior to placebo for treating fat malabsorption and (ii) superior to other supplements based on randomized cross-over trials.

METHODS

A computer-assisted search of MEDLINE and EMBASE was performed to identify relevant studies. Data extraction on study design, improvement in coefficient of fat absorption, diarrhoea and adverse events using prespecified forms.

RESULTS

A total of 12 manuscripts met inclusion criteria. Most studies (10/12) compared pancreatic enzyme supplements that used different delivery systems, while using similar quantities of enzymes. These studies found no consistent difference in fat malabsorption or gastrointestinal symptoms between different active treatments. Two small placebo-controlled trials (n = 65 patients) demonstrate that pancreatic enzyme supplements are superior to placebo for fat absorption. Data are inadequate to determine if pancreatic enzyme supplements lead to weight gain or improvement in diarrhoea.

CONCLUSIONS

Based on data from randomized cross-over trials, pancreatic enzyme supplements appear to improve fat malabsorption. No specific branded product or specific delivery system is superior for treatment of fat malabsorption in patients with exocrine pancreatic insufficiency.

Pancreatic enzyme replacement therapy for young cystic fibrosis patients

Maldigestion in cystic fibrosis (CF) affects approximately 90% of patients. As soon as pancreatic insufficiency is identified, enzyme supplementation is prescribed even with breast fed infants. A pancreatic enzyme preparation developed particularly for infants, Creon for children (CfC), contains smaller granules to be administered with a dosing spoon (5000 lipase units per scoop).

PATIENTS AND METHODS

In a prospective, randomised, multi-centre study, 40 infants and toddlers received both CfC and Creon 10000 (C10) for two weeks each in a cross-over design. Dosing of pancreatic enzymes was continued as applied before the study. The primary endpoint was the parents' treatment preference. Secondary endpoints included coefficient of fat absorption (CFA), clinical symptoms and safety parameters.

RESULTS

20 parents (51%) from the N=39 intent to treat sample preferred CfC, 9 (23%) preferred C10, and 10 (26%) had no preference The applied doses led to a mean CFA with similar results for both treatments (77.8% vs. 78.7%). Gastrointestinal symptoms were reported on a number of study days, and some children had abnormal results for laboratory parameters of malabsorption. Safety and tolerability of the preparations were good and all these parameters were comparable for both treatments.

CONCLUSION

Those parents who had a preference favoured CfC over C10. Both enzyme preparations improved malabsorption to a similar degree, although the applied dosages could have been too low in some children reflected in a suboptimal CFA. These data support the use of CfC for young patients with cystic fibrosis improving the daily care of this cohort detected mainly now through neonatal screening programmes.

In Vitro Comparison of Physical Parameters, Enzyme Activity, Acid Resistance, and pH Dissolution Characteristics of Enteric-Coated Pancreatic Enzyme Preparations: Implications for Clinical Variability and Pharmacy Substitution

OBJECTIVE Pancreatic enzyme products were available before the 1938 passage of the Federal Food, Drug, and Cosmetic Act and have to date been marketed without required safety and efficacy testing. Despite a lack of demonstrated bioequivalence, they are often substituted for each other without physician or patient consent or monitoring. We investigated the in vitro variability of key performance parameters among a representative group of currently available pancreatic enzyme formulations.MATERIALS AND METHODS Three "branded" preparations (Creon 20 Minimicrospheres, Pancrease MT 20, Ultrase MT 20) and 3 "generic" formulations (Pangestyme CN-20, Pancrelipase 20,000 URL, and Lipram CR 20) were evaluated in vitro for physical parameters of the capsules, actual vs. labeled enzyme activity, resistance of the enteric coating to simulated gastric acid, and kinetics of simulated duodenal lipase release. All products were labeled as providing 20,000 units of lipase activity per capsule.RESULTS All products varied considerably in the percentage relationship between actual and labeled lipase activity. Actual lipase activity exceeded 165% of the label claim in 4 batches of the Pangestyme product and 1 batch of the Lipram product. All batches of the Creon, Lipram, Ultrase, and Pancrease products were found to have residual lipase activity above 80% of their baseline measurements after testing in simulated gastric acid; residual lipase activity varied significantly among batches of the Pangestyme product and was only 1% for the Pancrelipase product. The Creon and Lipram products demonstrated effective protection by the enteric coating at pH <6.0 and rapid release of enzymatic activity at pH ≥6.0. The Pangestyme and Pancrelipase products showed substantial activity of released enzymes already at pH 5.0. Release kinetics were inconsistent between batches for the Ultrase and Pancrease products.CONCLUSION This study confirms the existence of "branded"-to-"generic," product-to-product, and batch-to-batch variability among representative pancreatic enzyme formulations with pharmaceutically equivalent labels. The results confirm current cautions regarding pharmacy substitution of pancreatic enzyme products and support the announcement by the US Food and Drug Administration, made subsequent to this study, that as of April 2008 approved new drug applications will be required in order to ensure the quality, potency, and stability of these products.

The effects of oral pancreatic enzymes (Creon 10 capsule) on steatorrhea: a multicenter, placebo-controlled, parallel group trial in subjects with chronic pancreatitis

OBJECTIVES

Creon 10 Minimicrospheres is an enteric-coated, delayed-release pancrelipase preparation designed to deliver active pancreatic enzymes to the small intestine. The primary objective of this study was to compare the effect of Creon 10 with placebo in the control of steatorrhea in chronic pancreatitis patients. Secondary objectives included evaluation of stool parameters and global improvement of symptoms scales.

METHODS

The study was a randomized, double-blind, placebo-controlled, 2-week trial. After a placebo run-in ("washout") phase, the effect on coefficient of fat absorption (%), daily fat excretion before and after treatment, and stool frequency and consistency were assessed.

RESULTS

In Creon 10-treated subjects, the change in mean coefficient of fat absorption (%) from run-in to double-blind phase was significantly higher compared with placebo-treated subjects (+36.7 vs. +12.1, P = 0.0185). Stool consistency improved significantly more with Creon 10 than with placebo (P = 0.0102) resulting in more subjects with formed stool; stool frequency decreased significantly more with Creon 10 than with placebo (P = 0.0015) from 10.8 during placebo run-in to 5.2 stools per day during double-blind treatment; and daily mean fat excretion in stool decreased significantly more (-56.5 vs. -11.4 g/d, P = 0.0181) in Creon 10-treated subjects compared with placebo-treated subjects. Global disease symptom scores showed greater improvement for both physicians and subjects in the Creon 10 group relative to those receiving placebo. Between treatment difference reached statistical significance for Creon 10 (P = 0.0435) for physician score and showed a trend (P = 0.0634) favoring Creon for subject score.

CONCLUSIONS

This randomized, placebo-controlled trial found that Creon 10 treatment controlled steatorrhea, as reflected in reduced fat excretion, decreased stool frequency and improved stool consistency. Creon 10 treatment was safe and well tolerated.

Diagnosis and treatment of intestinal malabsorption in cystic fibrosis

Intestinal malabsorption is severe and of early onset in virtually all people who have cystic fibrosis. The main cause is deficiency of pancreatic enzymes. Bicarbonate deficiency, abnormal bile salts, mucosal transport problems, motility differences, and anatomical structural changes are other contributory factors. Effective treatment should allow a normal to high-fat diet to be taken, control symptoms, correct malabsorption, and achieve a normal nutritional state and growth. Appropriate pancreatic enzyme replacement therapy will achieve normal or near-normal absorption in most people with cystic fibrosis. Early identification and treatment of intestinal malabsorption is critical to achieving optimal nutritional status. The occurrence of fibrosing colonopathy in a few patients on very high doses of those enzymes which have the copolymer Eudragit L30 D55 in their covering resulted in guidelines in the UK to avoid doses equivalent to more than 10,000 IU lipase per kg per day, and also to avoid preparations containing this copolymer in children and adolescents. For patients not responding to 10,000 IU lipase per kg per day review of adherence to treatment, change of enzyme preparation, variation in time of administration, and reduction in gastric acid may improve absorption. The importance of early investigation to exclude other gastrointestinal disorders as a cause of the patient's symptoms, rather than merely increasing the dose of enzymes, is stressed. With modern pancreatic enzymes in doses up to or only slightly in excess of 10,000 IU lipase per kg per day, adequate control of gastrointestinal symptoms and absorption can be achieved, and a normal nutritional state and growth rate maintained in most people with cystic fibrosis.

Comparison of two enteric coated microsphere preparations in the treatment of pancreatic exocrine insufficiency caused by cystic fibrosis

BACKGROUND

Pancreatic exocrine insufficiency is a common condition in patients with cystic fibrosis. Large amounts of pancreatic enzyme supplements are required to reduce malabsorption but patient compliance is not always optimal.

AIMS

To compare patients' preference and the efficacy of two enteric coated microsphere preparations in patients with cystic fibrosis.

PATIENTS

Patients with pancreatic exocrine insufficiency due to cystic fibrosis.

METHODS

Patients were assigned to the crossover treatment with Creon or Pancrease for 1 week and then to the alternative treatment. Patients had to follow a fixed diet (at least 2 g fat/kg) and had to assume 1000 units lipase/g fat. The evaluation parameters were: patients' preference, acceptance of therapy, stool fat excretion, stool weight, gastrointestinal symptoms, and tolerance.

RESULTS AND CONCLUSIONS

Of the 33/60 patients who expressed a preference for one of the two treatments, 30 preferred Creon while only 3 patients preferred Pancrease (p<0.001). No difference between the two treatments was observed regarding stool characteristics, gastrointestinal symptoms and tolerance. The mean number of capsules taken daily was reduced by 35% with Creon. The results of this study showed a preference in favour of Creon probably due to the reduction of daily capsule intake of 35%, supporting digestion as well as Pancrease.

Control of malabsorption in cystic fibrosis

Intestinal malabsorption is severe and of early onset in virtually all people who have cystic fibrosis. The main cause is deficiency of pancreatic enzymes, but bicarbonate deficiency, abnormalities of bile salts, mucosal transport and motility, and anatomical structural changes are other contributory factors. Appropriate pancreatic replacement therapy will achieve normal or near normal absorption in many patients. It is important to identify both malabsorption and evidence of a pancreatic lesion in all patients who are to receive pancreatic enzymes. All who have evidence of fat malabsorption are deemed pancreatic insufficient and candidates for enzyme replacement therapy. Effective treatment should allow a normal diet to be taken, control symptoms, correct malabsorption and achieve a normal nutritional state and growth. The occurrence of fibrosing colonopathy in some patients receiving very high doses of those enzymes that have the copolymer Eudragit L30 D55 in their covering has resulted in guidelines in the UK to avoid dosages greater than the equivalent of 10,000 IU lipase/kg/day for all patients and also to avoid preparations containing this copolymer in children and adolescents. For patients not responding to 10,000 IU lipase/kg/day, review of adherence to treatment, change of enzyme preparation, variation of the time of administration and reduction in gastric acid may improve absorption. The importance of excluding other gastrointestinal disorders as a cause of the patient's symptoms and the need for early investigations, rather than merely increasing the dosage of enzymes, is stressed. With modern enzymes, adequate control of gastrointestinal symptoms and absorption can be achieved at dosages of 10,000 IU lipase/kg/day or only slightly more, and a normal nutritional state and growth rate maintained in most patients with cystic fibrosis.

13C-egg white breath test: a non-invasive test of pancreatic trypsin activity in the small intestine

BACKGROUND

The recent availability of egg white protein highly enriched with (13)C has allowed breath test technology to be adapted for the study of protein digestion and absorption. Pancreatic trypsin is considered to be the key enzyme in the proteolytic cascade.

AIM

To evaluate trypsin activity in the small intestine of healthy volunteers and patients with pancreatic disease by a recently developed (13)C-egg white breath test.

METHODS

A total of 48 healthy volunteers and 30 patients with pancreatic disease were studied after ingestion of a test meal consisting of 22 g (13)C-labelled egg protein. Breath samples were taken before and after ingestion of the meal and analysed for (13)CO(2) concentration. Moreover, pancreatic trypsin output after maximal stimulation was measured in 13 patients and nine healthy volunteers.

RESULTS

The six hour cumulative (13)CO(2) excretion in breath was significantly lower in patients than controls (mean (SEM): 6.23 (0.82)% v 19.16 (0. 58)%, p<0.0001). An excellent correlation was found between the six hour cumulative (13)CO(2) excretion and trypsin activity after maximal pancreatic stimulation.

CONCLUSION

The non-invasive (13)C-egg white breath test is promising as an indirect pancreatic proteolytic function test.

Faecal bile acid and dietary residue excretion in cystic fibrosis: age group variations

BACKGROUND

Earlier studies report the excessive faecal excretions of bile acids and dietary residues in cystic fibrosis (CF). However, few of these investigated large groups of patients using modern pancreatin preparations and little data exists reporting carbohydrate excretion. We therefore aimed to characterise the general levels of malabsorption within age groups of 132 patients attending a regional CF centre.

METHODS

The faecal excretions of bile acids, fat, nitrogen and carbohydrate were measured. Most of these patients were treated with either (Creon) (n = 58) or Pancrease (n = 51) and prophylactic antibiotics. The patients were grouped in age ranges 0.5 to 5 years, 6 to 10 years, 11 to 15 years and >16 years. Carbohydrate excretion was determined in the 11 to 15 year group.

RESULTS

Increased excretions with increment in age group were found which, for bile acids, was twice that of age matched controls. Modest relationships were found between the overall excretion of bile acids and fat, and between the excretion of bile acids and nitrogen. Primary bile acids were a feature of cystic fibrosis stools but the patterns of individual bile acid excretion revealed a trend towards a normal bile acid types with increment in age group. Faecal carbohydrate was significantly increased to levels which may significantly alter large bowel microflora.

CONCLUSIONS

The data adds to the evidence that maldigestion initiates bile acid sequestration and consequently, the predominance of primary bile acids.

Gastric transit and pharmacodynamics of a two-millimeter enteric-coated pancreatin microsphere preparation in patients with chronic pancreatitis

It has been suggested that enteric-coated pancreatin microsphere (ECPM) preparations with sphere sizes larger than 1.7 mm pass through the stomach at a slower rate than a meal and therefore may be less efficacious in restoring pancreatic enzyme activity than preparations with smaller sphere sizes. The aim of this study was to investigate the gastric transit profile of a 2-mm ECPM preparation in relation to that of a solid meal and to simultaneously measure enzyme activities in eight patients with pancreatic exocrine insufficiency due to chronic pancreatitis. Gastric transit was assessed by double-isotope scintigraphy. A pancake was labeled with 99mTc. A 2-mm ECPM preparation was labeled with 171Er. Intraluminal pancreatic enzyme activities were assessed during a 6-hr period with the cholesteryl-[14C]octanoate breath test (for carboxyl ester lipase activity) and the N-benzoyl-L-tyrosyl-p-aminobenzoic acid/p-aminosalicylic acid (NBT-PABA/PAS) test (for chymotrypsin activity). The ECPM preparation passed through the stomach more rapidly (median 24 min) than the pancake (median 52 min, P < 0.05). During ECPM therapy, mean cumulative 14CO2 outputs rose significantly from 30% to 70% (P < 0.05), but remained below outcomes in healthy volunteers. Mean cumulative plasma PABA concentrations rose significantly from 46% to 87% (P < 0.05) and were not significantly different from outcomes in healthy volunteers. In chronic pancreatitis, a 2-mm ECPM preparation does not pass through the stomach more slowly than a solid meal, but in fact faster. Digestion of ester lipids and proteins showed an improvement to subnormal and normal levels, respectively.

Management of the Child With Cystic Fibrosis

Cystic fibrosis is one of the most common lethal inherited diseases among the Caucasian population, with an incidence of 1 in 2,000. With the progress made in the management of the disease, a once-regarded childhood illness has now an improved survival rate of up to 30 years. It is a multifaceted disease affecting a number of organ systems primarily pulmonary and gastrointestinal tract, with the former leading to most of the mortality. Therefore, good pulmonary toilet, including daily chest physiotherapy and appropriate antibiotic treatment for acute pulmonary exacerbations, remains the cornerstone of therapy. Disease-specific pharmacokinetics seen in these patients require special dosing considerations specifically for antibiotics to ensure adequate serum concentrations. In addition, bronchodilators, steroids, and mucolytics also play a role. With respect to the gastrointestinal tract, pancreatic insufficiency occurs and requires enzyme replacement. Intestinal obstruction may occur as early as the neonatal period, as "meconium ileus," and recur throughout the patient's lifespan. More recent modalities including chloride-channel facilitators, antiproteases, and gene therapy may hold promise to further improve the survival and quality of life in these individuals. The pharmacists' role is vital, especially with the unique pharmacokinetic considerations specific to this population and the complexity of medications necessary for appropriate management of the disease. Copyright © 1996 by W.B. Saunders Company

Nutritional management of cystic fibrosis

Nutritional support is an integral part of the management of cystic fibrosis patients. It is arguably best provided by a qualified dietitian and nutritional care sister working in conjunction with the rest of the cystic fibrosis team. The patient's nutritional needs should be assessed, regularly reviewed, and nutritional treatment tailored to meet the changing clinical and psychosocial needs of the patient. Nutritional intervention is not without complications, and in particular attention to normal feeding behaviour and vigilance when instituting supplementary nutrition may prevent many feeding difficulties.

High- versus low-lipase acid-resistant enzyme preparations in cystic fibrosis: a crossover randomized clinical trial

High-strength pancreatic enzyme preparations have recently come into widespread use in some countries for treatment of pancreatic insufficiency in cystic fibrosis. However, the therapeutic equivalence of these preparations to the standard acid-resistant microsphere preparations, under the same lipase dosage, has not been demonstrated by appropriate clinical trials; they are also considered responsible for severe colonic stricture. In a randomized crossover study, 20 adolescent or adult cystic fibrosis patients were treated in hospital with both low-lipase (A) and high-lipase (B) enteric-coated microsphere preparations. The fat excretion coefficient, evaluated over two 72-h fat balance periods (measured fat intake, 1.43 to 3 g/kg/day according to age), was the main response variable, secondary variables being stool wet and dry weight, fecal nitrogen output, and energy loss. With both preparations, patients were given a daily dose of 1,500-2,000 lipase BP U/g fat ingested, distributed across four meals. The low-strength preparation was divided into three doses during each meal, while the high-strength preparation was taken as a single dose in the middle of each meal. The considerable variability of results did not provide conclusive evidence of equivalence or significant differences between the two preparations in terms of steatorrhea and other variables. However, mean differences between the two treatments and their 95% confidence intervals showed less satisfactory results with the high-lipase preparation. A high-strength preparation is thought to release relatively less enzyme activity in the small intestine, forcing patients to increase their dosage and possibly creating a dangerous enzyme hyperconcentration in the large intestine. For this reason, the occasional occurrence of colonic stricture should be borne in mind, as must the possible scope for division of dosage during each meal.

Comparison of a high lipase pancreatic enzyme extract with a regular pancreatin preparation in adult cystic fibrosis patients

BACKGROUND

Malabsorption due to exocrine pancreatic insufficiency is the main gastrointestinal problem in cystic fibrosis. Despite high doses of pancreatic enzyme supplements it is often not possible to normalize fat absorption. We compared a new high lipase pancreatic enzyme preparation (Pancrease-HL; Cilag, Brussels, Belgium), containing enteric coated microspheres with 25,000 U of lipase, 22,500 U of amylase and 1250 U of protease per capsule, with regular Pancrease capsules, containing 5000 U of lipase, 2900 U of amylase and 330 U of protease per capsule.

METHODS

In a randomized double-blind crossover study, 13 cystic-fibrosis patients (6 male, 7 female, mean age 27.7 years) received either four capsules of Pancrease t.d.s. or one capsule of Pancrease-HL t.d.s. Patients took 20 mg omeprazole daily to raise intra-duodenal pH and thus optimize release of enzymes from the enteric coated microspheres.

RESULTS

With four capsules of Pancrease t.d.s., mean fat excretion was 15.4% and mean nitrogen excretion was 19.9% vs. 15.5% fat and 19.9% nitrogen excretion with one capsule Pancrease-HL t.d.s. Fat and protein energy loss (as a percentage of total daily intake) was 18.3% with Pancrease and 18.2% with Pancrease-HL. The differences were not statistically significant. Pancrease-HL was well tolerated, with no difference in abdominal pain or general well-being scores. The number and average weight of stools passed remained the same.

CONCLUSIONS

One capsule of Pancrease-HL appears to be equivalent to four capsules of regular Pancrease. Treatment with less capsules per day with the same efficacy may facilitate patient compliance.

Clinical pharmacology of pancreatic enzymes in patients with cystic fibrosis and in vitro performance of microencapsulated formulations

Improving protein and fat absorption in patients with cystic fibrosis relates to the amount of biologically active enzyme reaching the duodenum. Microencapsulated formulations are more effective than conventional products but differ in content, ability to retard acid inactivation and the pH at which they release enzymes. Contaminants in these products contribute to hyperuricosuria.

Measurement of fat digestion in early life using a stable isotope breath test

13C breath tests are a safe, non-invasive way of assessing nutrient digestion and absorption that can be used repeatedly in infancy and childhood. The aim of this study was to assess their value for measuring fat digestion in infants and young children with cystic fibrosis, and healthy controls whose pancreatic exocrine function is immature, and to monitor pancreatic enzyme supplementation. Six infants with cystic fibrosis (aged 10-18 months) and nine healthy controls (aged 6-19 months) were studied. After an overnight fast each child ingested 7.5 mg/kg 13C trioctanoin (99 atom % excess) followed by a known volume of milk. Breath samples were collected before and at 30 minute intervals thereafter for five hours. The 13C enrichment of expired carbon dioxide was measured by gas isotope ratio mass spectrometry. The mean (SD) percentage dose recovery of 13C was 13.5 (5.3) for the cystic fibrosis group and 24.2 (6.7) for the healthy controls. When those with cystic fibrosis were studied after supplementary pancreatic enzymes, the mean percentage dose recovery rose to 17.1 (6.9). Total intraluminal lipolysis was diminished by 44% in young children with cystic fibrosis. Pancreatic enzyme supplements improved digestion by 27%. The 13C trioctanoin breath test was effective in detecting fat maldigestion and can be used to measure the benefits of enzyme supplements in early life.

A double blind lipase for lipase comparison of a high lipase and standard pancreatic enzyme preparation in cystic fibrosis

A standard acid resistant microsphere pancreatic enzyme preparation was compared with identical capsules half filled with mini-tablets of a new high lipase preparation in a randomised double blind crossover study in children with cystic fibrosis. Each patient received his/her usual number of capsules and the same dose of lipase during each period of the study. Eighteen patients completed the study. There were fewer gastrointestinal symptoms when pancreatic enzyme was supplied as the high lipase preparation. There was also a significant improvement in fat absorption (17%, 95% confidence interval (CI) 6 to 27), reduction in faecal fat output (15.8 g/day, 95% CI 6.4 to 22.5), and faecal energy loss (789 kJ/day, 95% CI 211 to 1384). It is concluded that half filled capsules of the new high lipase preparation are more effective than the standard preparation and it is likely that filled capsules would allow patients to use fewer than half the number of pancreatic enzyme capsules.

Enzymes as agents for the treatment of disease

The replacement of genetically deficient enzymes in patients with inherited metabolic disorders by infusion of purified enzymes or by organ transplantation has had very limited success, although good results with bone marrow transplantation have been obtained in some patients with mucopolysaccharidosis, Gaucher disease and inherited immunodeficiency diseases. Genetic engineering of the patient's lymphocytes may ultimately render these approaches redundant, at least for some of these diseases. Treatment of chronic pancreatic insufficiency and of disaccharidase deficiency with oral enzymes can be very effective; therapy can be monitored in the latter by measuring the breath hydrogen excretion and in the former by a range of tests of which stool chymotrypsin assay is the most convenient. Treatment of acute myocardial infarction by intracoronary perfusion of thrombolytic enzymes can improve both cardiac function and long-term survival if given early enough. Successful reperfusion can be identified by changes in the kinetics of serum enzyme release and clearance, especially for the isoenzymes and isoforms of creatine kinase. In cancer chemotherapy, L-asparaginase has long been a useful adjunct in the treatment of acute lymphoblastic leukemia, but recent experience suggests a role in acute nonlymphoblastic leukemia as well.

Role of feeding in the treatment of dogs with pancreatic degenerative atrophy

Fourteen dogs with pancreatic degenerative atrophy (PDA) were fed their original diets or a special diet for 2 periods of 4 weeks to compare the severity of clinical signs in relation to different types of diet. During the first period, the dogs were given ordinary food, and in the second period, the dogs were given only the special diet that consisted of a commercial moderate-fat, low-fiber, highly-digestible food. In addition, equal amounts of pancreatic enzymes were added into the food during highly-digestible food. In addition, equal amounts of pancreatic enzymes were added into the food during both periods. The owners were given a questionnaire covering 9 typical signs of PDA. They were asked to assess the severity of signs daily for the 2 periods using a scale provided with the questionnaire. The general well-being of the dogs was significantly (p less than 0.05) better during the period when the dogs were fed a special diet. Of the individual clinical signs associated with PDA the severity of flatulence, borborygmi, volume of faeces and frequency of defecation were significantly (p less than 0.05) decreased on the special diet. There were no significant differences in appetite, drinking, colour and consistency of the faeces or in coprophagy between the 2 feeding periods. The costs of the special diet were almost double compared to the ordinary diets.

Energy content of stools in normal healthy controls and patients with cystic fibrosis

Stool energy losses and the sources of energy within the stool were determined in 20 healthy controls and 20 patients with cystic fibrosis while on their habitual pancreatic enzyme replacement treatment. Stool energy losses were equivalent to 3.5% of gross energy intake in healthy children (range 1.3-5.8%). Despite a comparable gross energy intake, stool energy losses were three times greater in patients with cystic fibrosis than controls averaging 10.6% of gross energy intake (range 4.9-19.7%). Stool lipid could account for only 29% and 41% of the energy within the stool in controls and patients with cystic fibrosis respectively and was poorly related to stool energy. Approximately 30% of the energy within the stool could be attributable to colonic bacteria in both the healthy children and patients with cystic fibrosis. These results suggest that stool energy losses in healthy children are relatively modest but that even when patients with cystic fibrosis are symptomatically well controlled on pancreatic enzyme replacement, raised stool energy losses may continue to contribute towards an energy deficit sufficient to limit growth in cystic fibrosis. As the energy content per gram wet weight remains relatively constant (8 kJ/g), stool energy losses may be estimated from simple measurements of stool wet weight.

Prevalence of diabetes mellitus and impaired glucose tolerance in cystic fibrosis

The aim of this study was to evaluate the prevalence of impaired glucose tolerance or diabetes mellitus in 99 patients (53 M, 46 F; mean age 10.5 +/- 6.9 years), with cystic fibrosis. Glucose tolerance was evaluated in all patients without overt diabetes using the oral glucose tolerance test (OGTT). Six patients showed a pathological OGTT and 2 patients had insulin-requiring diabetes mellitus. The mean age of the patients with impaired glucose tolerance was significantly higher than that of the subjects with normal glucose metabolism (p less than 0.0001). Patients with overt diabetes mellitus were the oldest subjects in the study group.

Cystic fibrosis, pathophysiological and clinical aspects

Cystic fibrosis is a lethal, hereditary, until recently little understood disease, which leads to progressive functional disturbances in various organs, including the lungs, liver and pancreas. Knowledge of the genetic and cellular abnormalities is rapidly progressing, but therapy is still symptomatic and based on insufficiently controlled and short-term studies. At present the therapeutic approach aims to combat respiratory infections by optimal antibiotic therapy, combined with techniques to promote sputum evacuation. Additional measures attempt to optimise both nutritional state and physical condition. Median survival has improved from approximately 1 year to about 25 years during the past 3 decades. This article summarises present information on disease mechanisms and treatment.

Two enteric coated microspheres in cystic fibrosis

In a randomised single blind crossover study in children with cystic fibrosis and pancreatic insufficiency, two enteric coated microsphere preparations of pancreatin were compared on a capsule for capsule basis, by measuring the coefficient of fat absorption, nitrogen excretion, weight change, and symptom scores after four weeks' treatment with each preparation. Thirty nine subjects were randomly allocated to receive Pancrease followed by Creon or vice versa. Each individual subject received the same number of capsules per day in each study period. Data from 27 children (Pancrease/Creon, n = 13 and Creon/Pancrease, n = 14) wer suitable for analysis. Results showed no significant differences between the two preparations in any variable studied. We conclude that there is no significant difference between Pancrease and Creon when compared on a capsule for capsule basis.

A comparison of enteric coated microspheres with enteric coated tablet pancreatic enzyme preparations in cystic fibrosis. A controlled study

A comparative study of the efficacy of pH sensitive enteric coated microspheres (ECM) with an enteric coated tablet (ECT) pancreatic enzyme preparation was carried out in 20 children with cystic fibrosis in a double-blind double-placebo crossover manner. Steatorrhoea was assessed by 3 day faecal fat analysis and dosage of medication, stool frequency and consistency; abdominal pain and appetite were documented by a patient-kept diary card. ECM controlled steatorrhoea (11.8 +/- 9.2 g vs 23.2 +/- 18.9 g, P less than 0.02), stool frequency (1.7 +/- 0.6 vs 2.1 +/- 0.9, P less than 0.01) and abdominal pain (8.8 +/- 13.8 vs 23.4 +/- 24.1, P less than 0.05) significantly better than ECT. Out of 20 patients 17 preferred ECM to ECT (P less than 0.00036). ECM preparations should allow more satisfactory dietary management of patients with cystic fibrosis with longterm beneficial effect.

Role of feeding in the treatment of dogs with pancreatic degenerative atrophy

Fourteen dogs with pancreatic degenerative atrophy (PDA) were fed their original diets or a special diet for 2 periods of 4 weeks to compare the severity of clinical signs in relation to different types of diet. During the first period, the dogs were given ordinary food, and in the second period, the dogs were given only the special diet that consisted of a commercial moderate-fat, low-fiber, highly-digestible food. In addition, equal amounts of pancreatic enzymes were added into the food during highly-digestible food. In addition, equal amounts of pancreatic enzymes were added into the food during both periods. The owners were given a questionnaire covering 9 typical signs of PDA. They were asked to assess the severity of signs daily for the 2 periods using a scale provided with the questionnaire. The general well-being of the dogs was significantly (p less than 0.05) better during the period when the dogs were fed a special diet. Of the individual clinical signs associated with PDA the severity of flatulence, borborygmi, volume of faeces and frequency of defecation were significantly (p less than 0.05) decreased on the special diet. There were no significant differences in appetite, drinking, colour and consistency of the faeces or in coprophagy between the 2 feeding periods. The costs of the special diet were almost double compared to the ordinary diets.

Energy and nutrient intakes in cystic fibrosis

The diets of 20 children with cystic fibrosis were analysed for energy and nutrient content with simultaneous measurement of energy losses in stools. Median energy intakes were in excess of the WHO estimated daily requirements (118.2%) when expressed as MJ/kg/24 hours, the excess almost accounted for by energy losses in the stools. When expressed as MJ/24 hours, however, median energy intakes were 98.7% of that estimated for normal children of median weight for age. Compared with recently published data for normal school children the fat content of the diet was reduced (30.0%) as were intakes of iron and zinc. Children whose whole milk intakes were high had the greatest amount of fat and energy in their diets and were able to absorb energy in excess of that recommended. We conclude that many children with cystic fibrosis are still on low fat diets and whole milk is the single most useful food for the provision of extra dietary fat and energy.

Treatment of steatorrhoea in cystic fibrosis: a comparison of enteric-coated microspheres of pancreatin versus non-enteric-coated pancreatin and adjuvant cimetidine

Enteric-coated microspheres of pancreatin were compared with non-enteric-coated pancreatin combined with cimetidine taken 40 min before meals in the treatment of patients with cystic fibrosis. Fourteen adults with steatorrhoea due to cystic fibrosis were investigated in an open, randomized crossover study, over two consecutive 28-day treatment periods. Lipase intake was adjusted to each patient's previous requirements and was the same during both months; they were instructed to continue with their normal diet. Patients collected faeces for 72 h at the end of each month and completed diary cards daily throughout. Bowel actions were less frequent on enteric-coated microspheres of pancreatin than on non-enteric-coated pancreatin/cimetidine (1.7 vs. 2.4/day; P less than 0.001) and stool character was improved (P less than 0.001). Mean daily faecal weight was similar on enteric-coated microspheres of pancreatin to that on the combination (254 g vs. 291 g; N.S.), whereas daily faecal fat excretion tended to be less on enteric-coated microspheres of pancreatin (21 g vs. 27 g; N.S.), and percentage fat absorption tended to be greater (81% vs. 73%; N.S.). Mean body weight increased by 0.3 kg on enteric-coated microspheres of pancreatin and fell by 0.1 kg on the combination (N.S.). These data indicate that enteric-coated microspheres of pancreatin are at least as effective as non-enteric-coated pancreatin with cimetidine in the treatment of steatorrhoea in cystic fibrosis.

Review: pancreatic enzyme replacement--applied physiology and pharmacology

The treatment of pancreatic steatorrhoea can often be improved by attention to the pathophysiological and pharmacological principles involved. Factors influencing the efficacy of pancreatic enzyme replacement include physiological characteristics of the individual patient and pharmaceutical characteristics of the supplement. Different patients may be best suited by different preparations and there is no overall 'best buy'. The new enteric-coated microsphere formulations are often most effective, but also more expensive than conventional preparations. Adjunctive H2-blockade can help appropriately selected patients with resistant steatorrhoea. Knowledge of the underlying cause may guide the choice of supplement and its dose, but trials of different regimens may prove necessary. Successful management, particularly of malnourished patients, involves optimization of dietary fat intake in addition to enzyme replacement.