Equipotent inhibition of gastric acid secretion by equal doses of oral or intravenous pantoprazole

Intermittent Proton Pump Inhibitor Therapy in Low-Risk Non-Variceal Upper Gastrointestinal Bleeding May Be Significantly Cost-Saving

BACKGROUND

High-dose proton pump inhibitor (PPI) therapy, given either intermittently or continuously for non-variceal upper gastrointestinal bleeding (NV-UGIB), is efficacious. Using intermittent PPI for low-risk patients may be cost-saving. Our objective was to estimate the annual cost savings if all low-risk NV-UGIB patients received intermittent PPI therapy.

METHODS

Patients who presented to hospital in Calgary, Alberta, who received a PPI for NV-UGIB from July 2015 to March 2017 were identified using ICD-10 codes. Patients were stratified into no endoscopy, high-risk, and low-risk lesion groups and further subdivided into no PPI, oral PPI, intermittent intravenous (IV), and continuous IV subgroups. Average length of stay (LOS) in each subgroup and costs were calculated.

RESULTS

We identified 4141 patients with NV-UGIBs, (median age 61, 57.4% male). One-thousand two-hundred and thirty-one low-risk patients received continuous IV PPI, with an average LOS of 6.8 days (95% CI 6.2-7.3) versus 4.9 days (95% CI 3.9-5.9) for intermittent IV patients. If continuous IV PPI patients instead received intermittent IV PPI, 3852 patient days and CAD 11,714,390 (2017 CAD)/year could be saved.

CONCLUSIONS

Using real-world administrative data, we demonstrate that a sizable portion of low-risk patients with NV-UGIB who were given continuous IV PPI if switched to intermittent IV therapy could generate significant potential cost savings.

Effect of Pantoprazole on the Absorption of Hydroxychloroquinea A Randomized Drug-Drug Interaction Trial in Healthy Adults

Hydroxychloroquine as a weak basic compound with two amines is strongly enriched in cell compartments with low pH, suggesting that modification of gastric pH by coadministered proton pump inhibitors might reduce its solubility and absorption and thus its efficacy in patients. We addressed this question in a single-center, open-label, randomized, parallel drug-drug interaction trial in healthy adults (EudraCT No. 2020-001470-30). All participants received a single oral dose of 400-mg hydroxychloroquine, and one group additionally received 40 mg of pantoprazole once daily for 9 days dosed to steady state. Whole-blood samples were collected for 72 hours, and hydroxychloroquine was quantified by liquid chromatography-tandem mass spectrometry. Primary endpoints were whole-blood hydroxychloroquine areas under the concentration-time curve from 0 to 72 hours (AUC_0-72h ) and peak concentrations (C_max ). Unpaired 2-sided t-tests of the log transformed pharmacokinetic parameters were performed to compare both groups. Twenty-four participants (12 per group) were included. Hydroxychloroquine AUC_0-72h and C_max did not differ between groups without and with pantoprazole (arithmetic mean; AUC_0-72h , 7649 ng/ml • h, and 8429 ng/ml • h, P = .50; C_max , 448 ng/mL and 451.5 ng/mL, P = .96, respectively). Pantoprazole did not alter hydroxychloroquine absorption, indicating that proton pump inhibitors do not affect its bioavailability.

Comparison of Oral versus Intravenous Proton Pump Inhibitors in Preventing Re-bleeding from Peptic Ulcer after Successful Endoscopic Therapy

BACKGROUND Proton pump inhibitors (PPIs) are now widely prescribed for the management of patients with acute upper gastrointestinal bleeding; although its optimal dose and route of administration has remained a controversial issue. The aim of this study was to assess the clinical effectiveness of high dose oral versus intravenous (IV) PPI after successful endoscopic therapy in patients with bleeding peptic ulcer disease. METHODS 178 patients with active upper gastrointestinal bleeding due to a peptic ulcer with stigmata of high risk for re-bleeding entered the study. After successful endoscopic hemostasis, they were randomized to receive either high dose oral pantoprazole (80 mg stat and 80 mg twice daily for 3 days) or high dose intravenous pantoprazole (80 mg IV infusion within 30 minutes and 8 mg per hour for 3 days). After the 3rd day, the patients in both groups received oral pantoprazole 40 mg twice daily for one month. The end points were comparing the rate of re-bleeding or mortality, and the need for blood transfusion or surgery during the first month between the two groups. RESULTS There were not significant statistical differences between the two groups in the volume of blood transfusion, mean duration of hospital stay, need to surgery, or mortality rates. However, the rates of re-bleeding were 2.3% (2:88) in the IV group and 3.3% (3:90) in the oral group (p = 0.6). CONCLUSION According to our findings, it seems that high dose oral PPI can be a good alternative to high dose IV PPI in patients with bleeding peptic ulcer who are at high risk of re-bleeding. Due to the lower cost and the availability of oral PPIs, their use can be economically much more affordable.

Interchangeable Use of Proton Pump Inhibitors Based on Relative Potency

Although proton pump inhibitors (PPIs) are widely used, their relative potency and ideal dosing regimens remain unclear. We analyzed data from randomized clinical trials that performed pH testing in patients receiving solid-dose PPI formulations (omeprazole, esomeprazole, lansoprazole, pantoprazole, rabeprazole) for a minimum of 5 days. We used omeprazole equivalency and the surrogate biomarker, percentage time pH > 4 over a 24-hour period (pH4time), to compare PPI effectiveness for different PPIs given once, twice, or 3 times daily. We found that increasing strength of once-daily PPIs (9-64 mg omeprazole equivalents) increased pH4time linearly from approximately 10.0 to 15.6 hours; higher doses produced no further increase in pH4time. Increasing the frequency to twice-daily PPI increased pH4time linearly, from approximately 15.8 to 21.0 hours. Three-times daily PPIs performed similarly to twice-daily PPIs. The costs of PPIs varied greatly, but the cost variation was not directly related to potency. We conclude that PPIs can be used interchangeably based on potency. Using twice-daily PPIs is more effective in increasing efficacy increasing once-daily PPI dosage. Omeprazole and lansoprazole (30 mg) and 20 mg of esomeprazole rabeprazole are functionally equivalent.

Value of Oral Proton Pump Inhibitors in Acute, Nonvariceal Upper Gastrointestinal Bleeding: A Network Meta-Analysis

BACKGROUND

Intravenous (IV) proton pump inhibitors (PPI) are the standard medical treatment in acute nonvariceal upper gastrointestinal bleeding (ANVGIB). Optimal route of PPI delivery has been questioned.

AIM

The aim was to perform a systematic review and network meta-analysis for the endpoints of risk of rebleeding, length of stay (LOS), surgery (ROS), mortality, and total units of blood transfused (UBT) among trials evaluating acid suppressive medications in ANVGIB.

METHODS

A total of 39 studies using IV PPI drip, IV scheduled PPI, oral PPI, H2-receptor antagonists, and placebo were identified. Network meta-analysis was used for indirect comparisons and Bayesian Markov Chain Monte Carlo methods for calculation of probability superiority.

RESULTS

No difference was observed between IV PPI drip and scheduled IV PPI for mortality (relative risk=1.11; 95% credibility interval, 0.56-2.21), LOS (0.04, -0.49 to 0.44), ROS (1.27, 0.64-2.35) and risk of rebleeding within 72 hours, 1 week, and 1 month [(0.98, 0.48-1.95), (0.59, 0.13-2.03), (0.82, 0.28-2.16)]. Oral PPIs were as effective as IV scheduled PPIs and IV PPI drip for LOS (0.22, -0.61 to 0.79 and 0.16, -0.56 to 0.80) and UBT (-0.25, -1.23 to 0.65 and -0.06, -0.71 to 0.65) and superior to IV PPI drip for ROS (0.30, 0.10 to 0.78).

CONCLUSION

Scheduled IV PPIs were as effective as IV PPI drip for most outcomes. Oral PPIs were comparable to scheduled IV for LOS and UBT and superior to IV PPI drip for ROS. Conclusions should be tempered by low frequency endpoints such as ROS, but question the need for IV PPI drip in ANVGIB.

Comparing intravenous and oral proton pump inhibitor therapy for bleeding peptic ulcers following endoscopic management: a systematic review and meta-analysis

BACKGROUND AND AIMS

The efficacy of proton pump inhibitors (PPIs) has been demonstrated for bleeding peptic ulcers but the route of administration remains controversial. Several studies have demonstrated that high-dose oral PPIs are as effective as intravenous PPIs in reducing recurrent bleeding. However, current guidelines recommend intravenous PPIs after endoscopic treatment. Previous data based on numbers that were too small to enable a firm conclusion to be reached suggested that oral and intravenous PPIs had equivalent efficacy. We undertook a meta-analysis to compare oral and intravenous PPIs in patients with bleeding peptic ulcers after endoscopic management.

METHODS

A literature search was undertaken using MEDLINE, EMBASE and the Cochrane Library, between 1990 and February 2016, to identify all randomized controlled trials (RCTs) that assessed the efficacy of PPIs administered by different routes. Nine RCTs, involving 1036 patients, were analysed. Outcomes were: recurrent bleeding, blood transfusion requirement, duration of hospital stay, a need for repeat endoscopy, surgery and 30-day mortality.

RESULTS

There were no differences in the rebleeding rates [odds ratio (OR) 0.93, 95% confidence interval (CI) 0.60, 1.46; P = 0.77], need for surgery (OR 0.77, 95% CI 0.25, 2.40; P = 0.65), need for repeat endoscopy (OR 0.69, 95% CI 0.39, 1.21; P = 0.19), need for blood transfusion [(MD) -0.03, 95% CI -0.26, 0.19; P = 0.76], duration of hospital stay (MD -0.61, 95% CI -1.45, 0.23; P = 0.16) or 30-day mortality (OR 0.89, 95% CI 0.27, 2.43; P = 0.84) according to the route of administration.

CONCLUSIONS

Oral PPIs represent better value for money, with clinical efficacy equivalent to intravenous PPIs.

Strategies for reduction in the duration of intravenous drug use: Interest of drug tracers as quality indicators to improve intravenous to oral switch

RATIONALE, AIMS, AND OBJECTIVES

Intravenous (IV) to oral (PO) drug switch is a challenge for tertiary care institutions for several reasons: catheter-related infections, patient's pain and discomfort or higher costs, and overuse of IV drugs considered as an irrational use of medicines. The objective was to evaluate yearly acetaminophen and proton-pump inhibiters' (PPIs) IV/PO ratios from 2011 to 2015 and to determine their correlation with all drugs IV/PO ratios and their relevance as drug tracers. A secondary objective was to estimate costs savings associated with a IV to PO switch improvement.

METHODS

Data on IV and PO consumptions and impact on costs were presented to physicians yearly, followed by the development of a computerized tool and pharmaceutical validation of prescriptions. Intravenous and PO drug consumptions were extracted yearly for all drugs, acetaminophen, and PPIs from 2011-01-01 to 2015-12-31. Acetaminophen and PPIs' IV/PO ratios were compared to IV/PO consumptions for all drugs. Costs savings associated with this switch were calculated yearly by multiplying the difference in average cost per dose by the total number of doses delivered (fixed purchase prices, euros) for both routes.

RESULTS

All drugs IV/PO ratio decreased every year to achieve a 16.3% reduction between 2011 and 2015. Acetaminophen and PPIs also decreased respectively by 35.5% and 16.5%. Same tendency of decrease of ratios year by year was noted for all drugs, PPIs, and acetaminophen. Savings for both acetaminophen and PPIs IV/PO switch were over 98 000€ for 5 years.

CONCLUSIONS

This study demonstrated that acetaminophen IV/PO ratio, easily produced in routine, was a relevant tracer to follow IV/PO switch improvement as it was correlated with all drugs IV/PO ratio. Direct cost savings associated with IV/PO switch improvements were consequent and illustrate well the impact of our approach on the efficiency of therapeutics' management.

Pantoprazole IV

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Through the cooperation of The Formulary, Hospital Pharmacy publishes selected reviews in this column. If you would like information about The Formulary Monograph Service or The F.I.X., call The Formulary at 800-322-4349. The August 2001 Formulary monographs are on almotriptan maleate, crotalidae polyvalent immune fab, drospirenone/ethinyl estradiol, fondaparinux sodium, and alfuzosin. The DUE is on peginterferon alfa-2b.

Bioavailability, safety, and pharmacodynamics of delayed-release dexlansoprazole administered as two 30 mg orally disintegrating tablets or one 60 mg capsule

BACKGROUND

Dual delayed-release dexlansoprazole is approved for use in adults as a 30 mg orally disintegrating tablet (ODT) or as 30 mg and 60 mg capsules. The pharmacokinetics, pharmacodynamics, and safety profile of two dexlansoprazole 30 mg ODTs were compared with one dexlansoprazole 60 mg capsule in this randomized, phase I, open-label, single-center, multiple-dose, two-period crossover study.

METHODS

Participants were randomized in one of two treatment sequences, each comprised two 5-day treatment periods during which two dexlansoprazole 30 mg ODTs or one 60 mg capsule was administered once daily. Pharmacokinetic parameters and the mean intragastric pH profile for the 24-hour period after dosing on days 1 and 5 were described. Adverse events were monitored during study duration and followed up with a phone call 5-10 days after the last dose of study drug.

RESULTS

On day 1, peak observed plasma concentration (Cmax) values were similar between two 30 mg ODTs (1047 ng/ml) and one 60 mg capsule (1164 ng/ml). Systemic exposure, measured by the area under the plasma concentration-time curve (AUC), was approximately 25% lower after ODT administration. On day 5, mean pH after daily doses of two 30 mg ODT or one 60 mg capsule was 4.33 and 4.36, respectively; both regimens maintained intragastric pH above 4.0 for 60% of the 24-hour period. Headache was the most commonly reported adverse event (observed in 19.2% of participants); no adverse events leading to study withdrawal occurred.

CONCLUSIONS

While systemic exposure (AUC) was 25% lower with ODT, peak concentrations (Cmax) after administration of two dexlansoprazole 30 mg ODTs and one 60 mg capsule were similar. The 24-hour intragastric pH control after administration of two dexlansoprazole 30 mg ODTs was equivalent to one dexlansoprazole 60 mg capsule. Both ODT and capsule were well tolerated.

Pharmacokinetics and pharmacodynamics of an orally disintegrating tablet formulation of dexlansoprazole

BACKGROUND

The pharmacokinetics and pharmacodynamics of a novel orally disintegrating tablet (ODT) formulation of delayed-release dexlansoprazole 30 mg was evaluated versus the dexlansoprazole 30 mg capsule in this phase I, open-label, multiple-dose, randomized, two-period crossover study.

METHODS

Healthy adults received daily doses of 30 mg dexlansoprazole ODT or 30 mg dexlansoprazole delayed-release capsule for 5 days during two treatment periods, separated by a 7-day washout interval. Blood samples for dexlansoprazole plasma concentrations and intragastric pH measurements were collected through 24 hours postdose on days 1 and 5 of each period.

RESULTS

Bioequivalence between the 30 mg ODT and 30 mg capsule dosage forms was demonstrated by the primary endpoints of dexlansoprazole peak concentration (C_max) and systemic exposure (AUC) values contained within the prespecified 90% confidence interval (CI) range of 0.80-1.25. Additional primary endpoints of intragastric mean pH values and percentage of time with pH > 4 over the 24-hour postdose interval were equivalent for dexlansoprazole ODT and dexlansoprazole capsule. Treatment-emergent adverse events were reported in 23% and 28% of participants receiving the ODT and capsule formulations, respectively. Headache was the most common adverse event in both treatment regimens (5.8% with ODT and 6.0% with capsule).

CONCLUSIONS

Administration of dexlansoprazole 30 mg ODT or 30 mg capsule provided equivalent plasma exposure when either was administered as a single dose or as once daily doses for 5 days. Pharmacodynamic equivalence between the two formulations was demonstrated by similar intragastric pH parameters on both day 1 and day 5. No effect of day on dexlansoprazole pharmacokinetics was observed. Dexlansoprazole ODT and dexlansoprazole capsule were both well tolerated.

24-Hour Measurement of Gastric pH in Rural South Africa

Background. Previous studies have established norms of 24-hour gastric pH profiles for western countries. This study was designed to establish the pattern for a rural African population with a high incidence of oesophageal cancer. Methods. After lower oesophageal manometry a probe was placed 10 cm distal to the lower oesophageal sphincter. We carried out 24-hour ambulatory monitoring of gastric pH on 59 healthy subjects. This was satisfactorily completed on 26 female and 18 male (age 21–64, median 35) subjects in the Transkei region of South Africa. Results. The mean 24 hour gastric pH was 2.84 and the mean night-time pH was 3.7. 40 volunteers recorded a night-time pH reaching over 4. 33 volunteers recorded a night-time pH over 7. Night-time alkalinisation was present for 136.4 minutes (25th centile 22.8, 75th centile 208.1) at pH4 or over, and 79.3 (2.5, 122.7) minutes at pH7 or over. Episodes of rapid alkaline rise were 17 (10, 47). 21.1% of these occurred while supine. 35 of 36 tested subjects were positive for H. pylori IgG. Conclusion. Gastric alkalinisation is common in Transkei, at a higher pH than that reported in other studies, and is sustained longer. Nighttime alkalinisation is frequent. This suggests a high level of duodenogastric reflux.

Meta-analysis: comparison of oral vs. intravenous proton pump inhibitors in patients with peptic ulcer bleeding

BACKGROUND

The efficacy of adjuvant use of intravenous proton pump inhibitors (PPIs) after endoscopic therapy has been proved in peptic ulcer bleeding patients, but the efficacy of oral PPIs is uncertain.

AIM

To compare the clinical outcomes of oral PPIs vs. intravenous PPIs in patients with peptic ulcer bleeding.

METHODS

Prospective randomised controlled trials were systematically searched from OVID databases until June 2012. Trials comparing oral and intravenous PPIs among patients with peptic ulcer bleeding were included. Recurrent bleeding, length of hospitalisation, blood transfusion, requirement of surgery and mortality were measured. The risk of bias, study quality and heterogeneity were also evaluated.

RESULTS

Six randomised trials from 2006 to 2011 were included. A total of 615 patients were randomly assigned to receive oral PPIs (n = 302) or intravenous PPIs (n = 313). The mean age was 60 years and 71.1% was male. No significant difference between oral and intravenous PPIs was observed regarding recurrent bleeding (RR: 0.92, 95% CI: 0.56-1.50), mean volume of blood transfused (-0.02 unit, 95% CI: -0.29-0.24 unit), requirement of surgery (RR: 0.82, 95% CI: 0.19-3.61) and all-cause mortality (RR: 0.88, 95% CI: 0.29-2.71). The duration of hospital stay in days was significantly shortened in those using oral PPIs (-0.74 day, 95% CI: -1.10 day to -0.39 day).

CONCLUSION

Oral PPIs demonstrate a similar effectiveness to intravenous PPIs among patients with peptic ulcer bleeding, but the results were combined from open-labelled trials with limited sample size. A large double-blind non-inferiority trial is required to better assess the role of oral PPIs.

Pantoprazole for the treatment of peptic ulcer bleeding and prevention of rebleeding

Adding proton pump inhibitors (PPIs) to endoscopic therapy has become the mainstay of treatment for peptic ulcer bleeding, with current consensus guidelines recommending high-dose intravenous (IV) PPI therapy (IV bolus followed by continuous therapy). However, whether or not high-dose PPI therapy is more effective than low-dose PPI therapy is still debated. Furthermore, maintaining pH ≥ 4 appears to prevent mucosal bleeding in patients with acute stress ulcers; thus, stress ulcer prophylaxis with acid-suppressing therapy has been increasingly recommended in intensive care units (ICUs). This review evaluates the evidence for the efficacy of IV pantoprazole, a PPI, in preventing ulcer rebleeding after endoscopic hemostasis, and in controlling gastric pH and protecting against upper gastrointestinal (GI) bleeding in high-risk ICU patients. The review concludes that IV pantoprazole provides an effective option in the treatment of upper GI bleeding, the prevention of rebleeding, and for the prophylaxis of acute bleeding stress ulcers.

Efficacy of oral famotidine and 2 omeprazole formulations for the control of intragastric pH in dogs

BACKGROUND

Little is known about the efficacy of commonly used acid suppressants on intragastric pH in dogs.

OBJECTIVE

To compare the effect of oral famotidine, 2 formulations of omeprazole, and placebo on intragastric pH in dogs with a catheter-free, continuous pH monitoring system.

ANIMALS

Six healthy adult mixed-breed colony dogs.

METHODS

Utilizing a randomized, 4-way cross over, open-label study, dogs were administered famotidine PO (1.0-1.3 mg/kg q12h), omeprazole tablet (1.5-2.6 mg/kg q24h), omeprazole reformulated paste (RP) (Gastrogard, 1.5-2.6 mg/kg q24h), and placebo for 7 days followed by a 10-day washout period. Radiotelemetric pH capsules were placed with gastroscopy assistance to continuously record intragastric pH for 4 days (days 4-7 of dosing). The percentage of time that intragastric pH was ≥3 and ≥4 was compared among treatment groups using repeated measures of analysis of variance. Tukey's Studentized range test was used to determine which groups were different with α= 0.05.

RESULTS

Mean ± SD percent time intragastric pH was ≥3 and ≥4 was 22 ± 8% and 14 ± 6% for famotidine, 63 ± 14% and 52 ± 17% for omeprazole tablet, 54 ± 17% and 44 ± 18% for omeprazole RP, and 6 ± 6% and 5 ± 5% for placebo. Both omeprazole formulations significantly increased intragastric pH compared with famotidine and placebo, but omeprazole tablet and RP was not significantly different from each other.

CONCLUSION

Oral omeprazole tablet and RP provide superior gastric acid suppression to famotidine, and should therefore be considered more effective for the treatment of acid related disorders in dogs.

A clinical guide to using intravenous proton-pump inhibitors in reflux and peptic ulcers

Intravenous (IV) proton-pump inhibitors (PPIs) are potent gastric acid suppressing agents, and their use is popular in clinical practice. Both IV and oral PPIs have similarly short half-lives, and their effects on acid secretion are similar, thus their dosing and dosage intervals appear to be interchangeable. The possible exception is when sustained high pHs are required to promote clot stabilization in bleeding peptic ulcers. Continuous infusion appears to be the only form of administration that reliably achieves these high target pHs. IV PPI is indicated in the treatment of high-risk peptic ulcers, complicated gastroesophageal reflux, stress-induced ulcer prophylaxis, Zollinger-Ellison syndrome, and whenever it is impossible or impractical to give oral therapy. The widespread use of PPIs has been controversial. IV PPIs have been linked to the development of nosocomial pneumonia in the intensive care setting and to spontaneous bacterial peritonitis in cirrhotic patients. This review discusses the use of IV PPI in different clinical scenarios, its controversies, and issues of appropriate use.

Management of Αcute Non-Variceal Upper Gastrointestinal Bleeding: Drugs, Endoscopic Hemostasis, or Both?

Acute upper gastrointestinal bleeding remains one of the most frequent and emergent conditions in everyday clinical practice and a challenge for doctors. Peptic ulcer is responsible for more than half of acute upper gastrointestinal bleeding and is the most frequent cause of serious non-variceal bleeding. Despite progress in diagnosis and management in these patients, the recurrence of bleeding remains an important problem. Several drugs and endoscopic techniques, alone or in combination, have been evaluated in many studies and there is presently enough experience in terms of their efficacy. Endoscopic hemostasis is more effective than any other therapeutic intervention in the treatment of patients with non-variceal upper gastrointestinal bleeding. In patients with high risk of rebleeding spots, the combination of endoscopic hemostasis with high dose proton pump inhibitors is the most effective strategy to reduce bleeding recurrences and the need for surgery.

Relative potency of proton-pump inhibitors-comparison of effects on intragastric pH

AIM

Comparative potency of proton-pump inhibitors (PPIs) is an important clinical issue. Most available trials have compared the different PPIs at one or a few selected specific dosages, making it difficult to derive quantitative equivalence dosages. Here we derived PPI dose equivalents based on a comprehensive assessment of dose-dependent effects on intragastric pH.

METHODS

All available clinical studies reporting the effects of PPIs on mean 24-h intragastric pH were sought from electronic databases including Medline. Studies included were restricted to those targeting the Caucasian population, and healthy volunteers or gastroesophageal reflux disease (GERD) patients. The dose-effect relationships for mean 24-h intragastric pH and for percentage of time with pH > 4 in 24 h were analyzed for each PPI using pharmacodynamic modeling with NONMEM and a model integrating all available data.

RESULTS

Fifty-seven studies fulfilled the inclusion criteria. Based on the mean 24-h gastric pH, the relative potencies of the five PPIs compared to omeprazole were 0.23, 0.90, 1.00, 1.60, and 1.82 for pantoprazole, lansoprazole, omeprazole, esomeprazole, and rabeprazole, respectively. Compared with healthy volunteers, patients with GERD needed a 1.9-fold higher dose and Helicobacter pylori-positive individuals needed only about 20% of the dose to achieve a given increase in mean 24-h intragastric pH.

CONCLUSION

The present meta-analysis provides quantitative estimates on clinical potency of individual PPIs that may be helpful when switching between PPIs and for assessing the cost-effectiveness of specific PPIs. However, our estimates must be viewed with caution because only a limited dose range has been tested and not exactly the same study conditions were applied for the different substances.

Prospective, randomized trial comparing effect of oral versus intravenous pantoprazole on rebleeding after nonvariceal upper gastrointestinal bleeding: a pilot study

Proton pump inhibitors (PPIs) reduce the rate of rebleeding in patients with nonvariceal upper GI bleed (NVGIB). Oral (PO) and intravenous (IV) pantoprazole are equipotent in raising gastric pH. We conducted a pilot study comparing the efficacy of PO vs. IV pantoprazole for reducing rebleeding after NVGIB. Patients with NVGIB were randomized to receive PO (80 mg BID for 3 days) or IV (80-mg IV bolus and 8 mg/hr infusion for 3 days) pantoprazole followed by pantoprazole, 40 mg PO BID, for 30 days. All patients underwent endoscopy within 24 hr and endotherapy was applied where necessary. Twelve patients randomized to the PO and 13 to the IV pantoprazole group were comparable in age, hematocrit, Rockall scores, ulcer characteristics, and endoscopic interventions. Two patients in the IV arm rebled and another in the IV arm developed reversible renal failure. No patient in the PO arm rebled, had organ failure, or had to be changed to IV pantoprazole. We conclude that in this pilot study, the effect of PO pantoprazole on 30-day rebleeding rate in patients with NVGIB was similar to that of IV pantoprazole.

Intravenous versus high-dose oral proton pump inhibitor therapy after endoscopic hemostasis of high-risk lesions in patients with acute nonvariceal upper gastrointestinal bleeding

Intravenous proton pump inhibitors (IV PPIs) decrease rebleeding following endoscopic hemostasis of bleeding peptic ulcers. Oral PPIs may be equally efficacious and may significantly reduce health care costs. This study aimed to compare outcomes in patients receiving oral versus IV PPI therapy following endoscopic hemostasis in patients with acute nonvariceal upper gastrointestinal bleeding (ANVUGIB). We performed a retrospective review of all patients who received PPI therapy following endoscopic hemostasis for ANVUGIB. The primary outcome was the adverse gastrointestinal event rate. One hundred sixty-two patients met the entry criteria (72 oral PPIs, 90 IV PPIs). The difference in the rate of adverse gastrointestinal events between the two groups was 1% (P = 0.85). Postendoscopic IV PPI use was associated with an odds ratio of 1.01 for developing an adverse outcome versus oral PPIs (95% CI: 0.44-2.33). We conclude that oral PPIs are probably equivalent to IV PPIs for preventing rebleeding in ANVUGIB patients.

Oral rabeprazole vs. intravenous pantoprazole: a comparison of the effect on intragastric pH in healthy subjects

BACKGROUND

Intravenous pantoprazole is often administered inappropriately to hospitalized patients who can take oral medications.

AIM

To compare the antisecretory effects of oral rabeprazole and intravenous pantoprazole in healthy subjects.

METHODS

In a double-blind, double-dummy, two-way crossover study, 38 Helicobacter pylori-negative volunteers were randomized to oral rabeprazole 20 mg or intravenous pantoprazole 40 mg daily for 3 days followed, after a 14-day washout period by the comparator treatment. Intragastric pH was recorded continuously for 24 h at baseline and on days 1 and 3 of each treatment period.

RESULTS

The mean (95% CI) percentage of the 24-h recording with gastric pH >4 was higher with rabeprazole than with pantoprazole on day 1: 37.7% (30.6-44.8%) vs. 23.9% (20.0-27.8). The mean percentage times with pH >3 and >4 for all intervals assessed were greater and the median 24-h intragastric pH values were higher with rabeprazole than with pantoprazole on days 1 and 3. The mean acidity index was lower with rabeprazole on days 1 and 3.

CONCLUSIONS

Oral rabeprazole 20 mg produced greater acid suppression than intravenous pantoprazole 40 mg. Therefore, it may be an appropriate and effective alternative in patients who can take oral medication.

Inappropriate use of intravenous pantoprazole: extent of the problem and successful solutions

BACKGROUND & AIMS

Indications for intravenous proton pump inhibitors (IV PPI) include upper gastrointestinal bleeding (UGIB) from peptic ulcer disease with high-risk stigmata and patients receiving nothing by mouth (NPO). The objectives were to assess the extent of errors in indications for IV PPI use and to determine whether multidisciplinary interventions could improve IV PPI use and costs.

METHODS

Part 1: Patients prescribed IV PPI during a period of 4 months were divided into 2 settings, UGIB or non-UGIB. The setting-specific appropriateness of the IV PPI indication and dosing regimen was determined. Part 2: Patients prescribed IV PPI before and after multidisciplinary interventions (educating physicians, a computerized dose template, pharmacists altering IV PPI orders in non-UGIB patients who were not NPO, and recommending a GI consult when a continuous infusion was ordered) were studied. Incidence of prescribing errors, IV PPI costs, and potential confounders were compared.

RESULTS

Part 1: Only 50% of UGIB (n = 145) patients received IV PPI for an appropriate indication. Both indication and dosing regimen were appropriate in 21%. In the non-UGIB group (n = 95), 33% were truly NPO; 51% had a correct dosing frequency. Part 2: The postintervention (n = 105) group (vs the preintervention group, n = 113) showed a significant absolute reduction in the degree of inappropriate indication in the UGIB (26%; 95% confidence interval [CI], 10%-42%; P < .0001) and in the non-UGIB (41%; 95% CI, 24%-58%; P < .0001) subgroups. However, a greater improvement in underspending than overspending meant that overall costs were unchanged.

CONCLUSIONS

IV PPI was frequently prescribed inappropriately and incorrectly; simple maneuvers resulted in reductions in errors.

Appropriate use of intravenous proton pump inhibitors in the management of bleeding peptic ulcer

Rebleeding from peptic ulcers is a major unsolved problem in the management of acute upper gastrointestinal bleeding. Our goal was to review what is known and what remains to be learned about the effectiveness of antisecretory therapy for acute upper gastrointestinal bleeding. We reviewed the data regarding the effectiveness of endoscopic therapy, the prediction of those at increased risk for rebleeding, and the effectiveness of antisecretory drug therapy in preventing rebleeding with or without endoscopic hemostasis. Proton pump inhibitor therapy without endoscopic hemostasis is ineffective clinically for stopping bleeding or preventing rebleeding. Endoscopic hemostasis remains the cornerstone of therapy. The data are consistent with the notion that reliable maintenance of the intragastric pH at > or = 6 after endoscopic hemostasis is associated with the lowest rebleeding rates. H2-receptor antagonists are ineffective for achieving this goal. Intermittent bolus and oral administration of proton pump inhibitors are equivalent and fail to achieve this goal, which can only be accomplished by bolus administration of a proton pump inhibitor (e.g., 80 mg) followed by a constant infusion (e.g., 8 mg/hr). Whether the combination of endoscopic hemostasis and pH control is equal or superior to selected second-look endoscopy is unknown. A treatment algorithm is suggested.

Collaboratively Designed Practice Guidelines Promote Appropriate Use of Intravenous Proton Pump Inhibitors

Objective

To determine the effectiveness of practice guidelines for proton pump inhibitor use at an academic medical center.

Methods

Patients initiated on intravenous (IV) pantoprazole therapy between July 2001 and May 2002 were evaluated prospectively for appropriateness of therapy. Pharmacists assessed clinical use, dosing strategy, administration route, and prescribing patterns.

Results

A total of 85 patients were evaluated. Only 25% of the patients were prescribed IV pantoprazole according to established institutional guidelines. The majority of therapy meeting guideline criteria were initiated on pantoprazole by the Gastroenterology service. Due to overuse of pantoprazole, prescribing guidelines were revised to specify indications with proven efficacy (erosive GERD, Zollinger-Ellison or other hypersecretory conditions, and upper gastrointestinal bleeding). Patients who received pantoprazole for stress ulcer prophylaxis, an unapproved indication, had therapy automatically switched to a histamine receptor antagonist. For patients who tolerated oral medications or enteral feedings, therapy was automatically converted to the oral dosage form.

Conclusions

Evaluation of institutional pantoprazole utilization revealed usage extending beyond indications with proven efficacy. Pharmacists and physicians collaboratively developed evidence-based practice guidelines; adherence to appropriate indications showed a 50% improvement.

Intra-oesophageal pH profiles and pharmacokinetics of pantoprazole and esomeprazole: a crossover study in patients with gastro-oesophageal reflux disease

AIM

To compare the effect of pantoprazole and esomeprazole on intra-oesophageal pH and investigate their pharmacokinetics in patients with symptomatic gastro-oesophageal reflux disease (GORD).

METHODS

Double-blind, randomized, two-period crossover study. Caucasian men with symptomatic GORD (n=48) were selected on the basis of clinical records of typical GORD symptoms, confirmed by a pathological reflux time (oesophageal pH<4 for > or =6% of the time). They received oral pantoprazole 40 mg once daily (od) or esomeprazole 40 mg od for seven days. Continuous 24 h oesophageal pH-metry was performed at baseline and day 7. Evaluations included: pre- and post-treatment differences in the percentage of time with pH<4.0 and <3.0 between baseline and day 7; area under the curve (AUC), Cmax, and T(1/2); point estimates and 90% confidence intervals (CI) on days 1 and 7, calculated for ratios of the AUC and Cmax.

RESULTS

Both drugs decreased the mean total number of reflux episodes and reduced the percentage of reflux time within 24 h to <3%. No pathological reflux was detectable after repeated administration of either drug. The 90% CI were within the predefined range at all time points; thus, equivalence of pantoprazole and esomeprazole was concluded. For pantoprazole, Cmax and AUC were unchanged on day 7 vs day 1, confirming its high and constant bioavailability. For esomeprazole, Cmax and AUC were increased on day 7 vs day 1 by 80% and 50%, respectively, indicating low initial bioavailability. No clinically relevant side effects were seen for either drug.

CONCLUSION

Pantoprazole and esomeprazole have equivalent effect on oesophageal pH, since no pathological reflux was detected after treatment with either drug. For esomeprazole, the Cmax and AUC increased after multiple dosing; for pantoprazole the pharmacokinetics were predictable and independent of the number of administered doses.

Evidence-based analysis: postoperative gastric bleeding: etiology and prevention

Although the incidence of stomach hemorrhage is declining, stress-related gastric bleeding remains an important source of morbidity and mortality in cancer patients undergoing major surgical procedures to remove tumor. Prevention of stress-related bleeding is desirable; however, the optimal use of drugs to prevent gastric bleeding is unclear. Prophylaxis is recommended for surgical patients who require prolonged mechanical ventilation or have a coaguloathy. Histamine-2 receptor antagonists and sucralfate will reduce the likelihood of clinically important gastric-bleeding. Sucralfate appears to be less effective than H-2 blockers, but it is associated with fewer side effects such as nosocomial pneumonia. Preliminary studies show that proton pump inhibitors are most effective, have few side effects, but are most expensive. Intravenous proton pump inhibitors may be the drugs of choice for stress ulcer prophylaxis (SUP) in high-risk patients.

Pantoprazole: an update of its pharmacological properties and therapeutic use in the management of acid-related disorders

Pantoprazole (Protonix) is an irreversible proton pump inhibitor (PPI) that reduces gastric acid secretion. In combination with two antimicrobial agents (most commonly metronidazole, clarithromycin or amoxicillin) for 6-14 days, pantoprazole 40 mg twice daily produced Helicobacter pylori eradication rates of 71-93.8% (intent-to-treat [ITT] or modified ITT analysis) in patients without known antibacterial resistance. Pantoprazole-containing triple therapy was at least as effective as omeprazole- and similar in efficacy to lansoprazole-containing triple therapy in large trials. In the treatment of moderate to severe gastro-oesophageal reflux disease (GORD), oral pantoprazole 40 mg/day was as effective as other PPIs (omeprazole, omeprazole multiple unit pellet system, lansoprazole and esomeprazole) and significantly more effective than histamine H(2)-antagonists. Pantoprazole 20 mg/day provided effective mucosal healing in patients with GORD and mild oesophagitis. Intravenous pantoprazole 40 mg/day can be used in patients who are unable to take oral medication. Oral pantoprazole 20-40 mg/day for up to 24 months prevented relapse in most patients with healed GORD. According to preliminary data, oral pantoprazole 20 or 40 mg/day was effective at healing and preventing non-steroidal anti-inflammatory drug (NSAID)-related ulcers, and intravenous pantoprazole was at least as effective as intravenous ranitidine in preventing ulcer rebleeding after endoscopic haemostasis. Oral or intravenous pantoprazole up to 240 mg/day maintained target acid output levels in most patients with hypersecretory conditions, including Zollinger-Ellison syndrome. Oral and intravenous pantoprazole appear to be well tolerated in patients with acid-related disorders in short- and long-term trials. Tolerability with oral pantoprazole was similar to that with other PPIs or histamine H(2)-antagonists in short-term trials. Formal drug interaction studies have not revealed any clinically significant interactions between pantoprazole and other agents. In conclusion, pantoprazole is an effective agent in the management of acid-related disorders. As a component of triple therapy for H. pylori eradication and as monotherapy for the healing of oesophagitis and maintenance of GORD, pantoprazole has shown similar efficacy to other PPIs and greater efficacy than histamine H(2)-antagonists. Limited data suggest that it is also effective in Zollinger-Ellison syndrome and in preventing ulcer rebleeding. Pantoprazole is well tolerated with minimal potential for drug interactions. The availability of pantoprazole as both oral and intravenous formulations provides flexibility when the oral route of administration is not appropriate. Thus, pantoprazole is a valuable alternative to other PPIs in the treatment of acid-related disorders.

Pharmacologic Management of Gastroesophageal Reflux Disease

The burden of gastroesophageal reflux disease (GERD) results from its widespread prevalence and the unfavorable impact of its symptoms on well-being and quality of life. Whereas abnormalities of the antireflux barrier (lower esophageal sphincter) are important in the pathophysiology of GERD, pharmacologic therapy for GERD is based on suppression of acid, which is responsible for the majority of the symptoms and for epithelial damage. Proton pump inhibitors (PPIs) are the agents of choice for achieving the goals of medical therapy in GERD, which include symptom relief, improvement in quality of life, and healing and prevention of mucosal injury. As a class, these drugs are extremely safe. The newest PPI, esomeprazole, brings a statistically significant increase in healing of mucosal injury and symptom relief in patients with erosive esophagitis, compared with omeprazole and lansoprazole. This article reviews the role of medical therapy in the short- and long-term management of symptomatic patients with or without erosive esophagitis, including extraesophageal presentations, GERD during pregnancy, and Barrett's esophagus. Management of refractory patients is addressed.

Pharmacologic management of gastroesophageal reflux disease

The burden of gastroesophageal reflux disease (GERD) results from its widespread prevalence and the unfavorable impact of its symptoms on well-being and quality of life. Whereas abnormalities of the antireflux barrier (lower esophageal sphincter) are important in the pathophysiology of GERD, pharmacologic therapy for GERD is based on suppression of acid, which is responsible for the majority of the symptoms and for epithelial damage. Proton pump inhibitors (PPIs) are the agents of choice for achieving the goals of medical therapy in GERD, which include symptom relief, improvement in quality of life, and healing and prevention of mucosal injury. As a class, these drugs are extremely safe. The newest PPI, esomeprazole, brings a statistically significant increase in healing of mucosal injury and symptom relief in patients with erosive esophagitis, compared with omeprazole and lansoprazole. This article reviews the role of medical therapy in the short- and long-term management of symptomatic patients with or without erosive esophagitis, including extraesophageal presentations, GERD during pregnancy, and Barrett's esophagus. Management of refractory patients is addressed.

Intravenous proton pump inhibitors in the critical care setting

Two well-controlled trials were carried out to investigate the effectiveness of intravenous proton pump inhibitors (PPIs) to reduce peptic ulcer rebleeding after successful hemostasis. The results demonstrated that the PPI reduced the rate of rebleeding significantly. The recent availability of the first intravenous PPI formulation in the United States, intravenous pantoprazole, represents an alternative to intravenous histamine-2 receptor antagonists. The results of 16 randomized, controlled trials involving a total of >3,800 patients (1,892 receiving PPIs and 1,911 controls) suggest that bolus administration plus continuous infusion of PPIs is a more effective pharmacotherapy than bolus infusion alone in decreasing both rebleeding and the need for surgery. Optimal effect is achieved with an intravenous 80-mg bolus, followed by continuous infusion of 8 mg/hr for 3 days, after which therapy may be continued with an oral PPI. Intermittent bolus administration yielded a minimal benefit. A difference in mortality rates has not yet been demonstrated.

A comparison of simplified lansoprazole suspension administered nasogastrically and pantoprazole administered intravenously: effects on 24-h intragastric pH

AIM

To compare the 24-h intragastric pH effects of simplified lansoprazole suspension, 30 mg, administered nasogastrically, with pantoprazole, 40 mg, administered intravenously.

METHODS

Thirty-six healthy adults were enrolled and given simplified lansoprazole suspension, 30 mg (nasogastrically), or pantoprazole, 40 mg (intravenously), once daily for five consecutive days in a cross-over fashion. Intragastric pH was monitored at baseline and on Days 1 and 5 of each treatment period. The pharmacokinetic parameters of lansoprazole and pantoprazole were also determined on Days 1 and 5.

RESULTS

No statistically significant changes in pharmacokinetic parameters occurred between Days 1 and 5 with either regimen, except for pantoprazole Cmax. On Days 1 and 5, significantly higher mean 24-h intragastric pH values were observed with 30 mg simplified lansoprazole suspension compared with 40 mg intravenous pantoprazole (Day 1, 3.13 vs. 2.67; Day 5, 3.95 vs. 3.61, respectively; P < 0.05). Additionally, 30 mg simplified lansoprazole suspension produced significantly (P < 0.05) higher percentages of time intragastric pH was above 3, 4, 5 or 6 as compared with 40 mg intravenous pantoprazole throughout Days 1 and 5.

CONCLUSIONS

A 30 mg dose of simplified lansoprazole suspension administered nasogastrically was consistently more effective at controlling intragastric pH than pantoprazole, 40 mg, administered intravenously.

Effects on 24-hour intragastric pH: a comparison of lansoprazole administered nasogastrically in apple juice and pantoprazole administered intravenously

OBJECTIVE

To compare the 24-h intragastric pH effects of lansoprazole, 30 mg administered nasogastrically, with pantoprazole, 40 mg administered i.v.

METHODS

Healthy adults were enrolled in an open label, two-way crossover, single-center study. Thirty milligrams of lansoprazole (administered nasogastrically in apple juice) or pantoprazole (i.v.) were administered once daily at 8:00 AM for 5 consecutive days with at least a 2-wk washout period between the regimens. Ambulatory 24-h intragastric pH was monitored at baseline and on days 1 and 5 of each treatment period. Blood specimens were collected on days I and 5 for pharmacokinetic parameter determinations.

RESULTS

Thirty-three adults completed both crossover periods, with the exception of one patient with a zero lansoprazole plasma concentration on day 1 of period 2. Lansoprazole, 30 mg per nasogastric tube, produced significantly higher mean 24-h intragastric pH values relative to pantoprazole, 40 mg i.v., on both day 1 (3.05 vs 2.76, p < 0.002) and day 5 (3.65 vs 3.45, p = 0.024). Lansoprazole sustained the intragastric pH above 3 (days 1 and 5), 4, and 5 (day 1) significantly longer relative to pantoprazole. Lansoprazole's time to the maximum observed concentration and area under the plasma concentration-time curve over the 24-h time interval increased significantly from day I to day 5 (1.7 h vs 2.0 h and 1865 ng x h/ml vs 2091 ng x h/ml, respectively), and a significant increase in half-life relative to day 1 (0.96 h) was observed on day 5 (1.03 h) during pantoprazole treatment.

CONCLUSION

Lansoprazole, 30 mg administered nasogastrically, effectively controls intragastric pH and is an alternative to i.v. pantoprazole in patients who are unable to swallow solid dosage formulations.

Rational Use of Parenteral Proton Pump Inhibitors

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Management of severe gastroesophageal reflux disease

Gastroesophageal reflux disease (GERD) affects more than one third of the population. It is generally a chronic condition and has the potential to be serious. Some patients with GERD experience persistent daytime or nighttime heartburn and some sustain severe damage, including ulceration, stricture, and Barrett's esophagus, which can predispose to development of adenocarcinoma. Extraesophageal manifestations of GERD can include otolaryngologic, respiratory, and cardiac problems. Severe GERD responds best to agents that suppress gastric acid secretion. Of these, proton pump inhibitors (PPIs) provide the most effective control of gastric acidity and are, therefore, the medical treatment of choice. In fact, nonresponse to a PPI should raise the suspicion that the diagnosis is not GERD. Proton pump inhibitors are quickly becoming the treatment of choice for GERD, especially for severe or refractory cases. For patients whose GERD is refractory even to PPIs or who are unwilling to face years of PPI therapy, antireflux surgery remains an option.

Switching between intravenous and oral pantoprazole

Proton pump inhibitors (PPIs) are the most effective antisecretory drugs available for controlling gastric acid acidity and volume. They are the drugs of choice in the treatment of moderate-to-severe gastroesophageal reflux disease, hypersecretory disorders, and peptic ulcers. Currently in the United States, they are only available in an oral formulation. However, pantoprazole will soon be available in an intravenous formulation and will extend the power of PPIs to inpatient hospital settings. Intravenous pantoprazole has been shown to be effective and safe in clinical trials. Intravenous pantoprazole is indicated for the treatment of patients who require PPI therapy but who are unable to take oral medication. Intravenous pantoprazole has been shown to maintain acid suppression in patients switched from oral PPIs, so no change in dosage is required when switching from one formulation to the other. Potential hospital-based uses for intravenous PPI therapy include perioperative use as prophylaxis for acid aspiration syndrome during induction of anesthesia, prophylaxis for stress-related mucosal disease, and management of gastrointestinal bleeding from stress or acid peptic disease.

Pantoprazole: a new proton pump inhibitor

OBJECTIVE

This paper reviews the pharmacology, clinical efficacy, and tolerability of pantoprazole in comparison with those of other available proton pump inhibitors (PPIs).

METHODS

Relevant English-language research and review articles were identified by database searches of MEDLINE, International Pharmaceutical Abstracts, and UnCover, and by examining the reference lists of the articles so identified. In selecting data for inclusion, the author gave preference to full-length articles published in peer-reviewed journals.

RESULTS

Like other PPIs, pantoprazole exerts its pharmacodynamic actions by binding to the proton pump (H+,K+ -adenosine triphosphatase) in the parietal cells, but, compared with other PPIs, its binding may be more specific for the proton pump. Pantoprazole is well absorbed when administered as an enteric-coated, delayed-release tablet, with an oral bioavailability of approximately 77%. It is hepatically metabolized via cytochrome P2C19 to hydroxypantoprazole, an inactive metabolite that subsequently undergoes sulfate conjugation. The elimination half-life ranges from 0.9 to 1.9 hours and is independent of dose. Pantoprazole has similar efficacy to other PPIs in the healing of gastric and duodenal ulcers, as well as erosive esophagitis, and as part of triple-drug regimens for the eradication of Helicobacter pylori from the gastric mucosa. It is well tolerated, with the most common adverse effects being headache, diarrhea, flatulence, and abdominal pain. In clinical studies, it has been shown to have no interactions with various other agents, including carbamazepine, cisapride, cyclosporine, digoxin, phenytoin, theophylline, and warfarin.

CONCLUSIONS

Pantoprazole appears to be as effective as other PPIs. Its low potential for drug interactions may give it an advantage in patients taking other drugs.

Clinical experience with pantoprazole in gastroesophageal reflux disease

BACKGROUND

Pantoprazole is a new proton pump inhibitor indicated for the treatment of erosive esophagitis associated with gastroesophageal reflux disease (GERD) and is available in both oral and intravenous (IV) formulations.

OBJECTIVE

This paper reviews the pharmacologic properties of pantoprazole and summarizes the findings from clinical studies of this drug.

METHODS

This review was compiled from the published literature, abstracts from clinical trials, and data on file with the manufacturer of pantoprazole.

RESULTS

Pantoprazole selectively accumulates in the acidic environment of gastric parietal cells and acts at the final step of acid secretion by binding 2 key cysteine residues of the proton pump involved in gastric acid production. The bioavailability of pantoprazole is not altered by concomitant administration of food or antacids or with repeated dosing. Both oral and IV formulations of pantoprazole exhibit linear pharmacokinetics. Several clinical trials have proved pantoprazole superior to histamine-2-receptor antagonists (H2RAs) in reducing acid secretion and elevating gastric pH levels. Pantoprazole has been shown to be more effective than ranitidine (P < 0.05), famotidine (P < 0.001), and nizatidine (P < 0.05), and at least as effective as omeprazole, in healing erosive esophagitis and relieving associated symptoms of GERD, including regurgitation. Pantoprazole is also more effective than the H2RA nizatidine for the treatment of nighttime heartburn (P < 0.05). Studies have shown pantoprazole to be well tolerated; adverse events, including headache, diarrhea, flatulence, abdominal pain, eructation, nausea, and rash, occurred in < or = 6% of patients. The oral and IV formulations of pantoprazole are equally potent in inhibiting gastric acid secretion; thus, switching between formulations requires no dosage adjustments. Special patient populations, including the elderly and patients with renal or mild to moderate hepatic impairment, can take pantoprazole without an adjustment in dosage.

CONCLUSIONS

Because of its unique pharmacokinetic properties, mechanism of action, and reduced potential for producing cytochrome P-450-based drug interactions, pantoprazole in both oral and IV formulations is effective over a full 24 hours and is well tolerated in a variety of patient types.

Intravenous pantoprazole rapidly controls gastric acid hypersecretion in patients with Zollinger-Ellison syndrome

BACKGROUND & AIMS

Parenteral control of gastric acid hypersecretion in conditions such as Zollinger-Ellison syndrome (ZES) or idiopathic gastric acid hypersecretion is necessary perioperatively or when oral medications cannot be taken for other reasons (e.g., during chemotherapy, acute upper gastrointestinal bleeding, or in intensive care unit settings).

METHODS

We evaluated the efficacy and safety of 15-minute infusions of the proton pump inhibitor pantoprazole (80-120 mg every 8-12 hours) in controlling acid output for up to 7 days. Effective control was defined as acid output >10 milliequivalents per hour (mEq/h) (<5 mEq/h in patients with prior acid-reducing surgery) for 24 hours.

RESULTS

The 21 patients enrolled had a mean age of 51.9 years (range, 29-75) and a mean disease duration of 8.1 years (range, <0.5-21); 13 were male, 7 had multiple endocrine neoplasia syndrome type I, 4 had undergone acid-reducing surgery, 2 had received chemotherapy, and 13 had undergone gastrinoma resections without cure. Basal acid output (mean +/- SD) was 40.2 +/- 27.9 mEq/h (range, 11.2-117.9). In all patients, acid output was controlled within the first hour (mean onset of effective control, 41 minutes) after an initial 80-mg intravenous pantoprazole dose. Pantoprazole, 80 mg every 12 hours, was effective in 17 of 21 patients (81%) for up to 7 days. Four patients required upward dose titration, 2 required 120 mg pantoprazole every 12 hours, and 2 required 80 mg every 8 hours. At study end, acid output remained controlled for 6 hours beyond the next expected dose in 71% of patients (n = 15); mean acid output increased to 4.0 mEq/h (range, 0-9.7). No serious or unexpected adverse events were observed.

CONCLUSIONS

Intravenous pantoprazole, 160-240 mg/day administered in divided doses by 15-minute infusion, rapidly and effectively controlled acid output within 1 hour and maintained control for up to 7 days in all ZES patients.

Oral and intravenous dosage forms of pantoprazole are equivalent in their ability to suppress gastric acid secretion in patients with gastroesophageal reflux disease

OBJECTIVE

The aim of this study was to assess the ability of pantoprazole to maintain gastric acid suppression in patients with gastroesophageal reflux disease who are switched from an oral (p.o.) to an intravenous (i.v.) dosage form.

METHODS

A total of 65 patients with gastroesophageal reflux disease were administered either 40 or 20 mg of p.o. pantoprazole daily for 10 days, then were switched to either a matching dose of i.v. pantoprazole or to placebo for 7 days. Acid output (basal and maximal) was measured at the end of the p.o. treatment period and on the first and last days of i.v. therapy. In the primary efficacy analysis, the acid output values at the end of the p.o. pantoprazole treatment were compared with those at the end of the i.v. treatment. Safety was monitored by periodic vital sign measurements, clinical laboratory evaluations, ophthalmic examinations, electrocardiograms, and reports of adverse events. The data were tested by an analysis of covariance and by Wilcoxon signed rank and t tests.

RESULTS

Maximal acid output (mean +/- SD) in the 40 mg and 20 mg pantoprazole group after p.o. treatment was 6.5 +/- 5.6 mEq/h and 14.5 +/- 15.5 mEq/h, respectively; whereas, at the end of the i.v. treatment period, the values were 6.6 +/- 6.3 mEq/h and 11.1 +/- 10.2 mEq/h, respectively. In patients given i.v. placebo, acid output was significantly (p < 0.05) increased to 29.2 +/- 13.0 mEq/h by day 7. Both p.o. and i.v. pantoprazole dosage forms had similar favorable safety and tolerability profiles.

CONCLUSIONS

The p.o. and i.v. formulations of pantoprazole (40 and 20 mg) are equivalent in their ability to suppress gastric acid output. The i.v. form of pantoprazole offers an alternative for gastroesophageal reflux disease patients who are unable to take the p.o. formulation.

Inhibition of pentagastrin-induced gastric acid secretion by intravenous pantoprazole: a dose-response study

OBJECTIVE

The purpose of this study was to compare the gastric acid inhibitory ability of increasing doses of intravenous (i.i.) pantoprazole with that of i.v. famotidine and placebo. Pentagastrin was infused continuously in healthy subjects as a model for patients with Zollinger-Ellison syndrome.

METHODS

Pentagastrin (1 microg/kg/h) was infused to stimulate maximum acid output in 39 subjects over a 25-h period. After 60 min of pentagastrin infusion, subjects received a single dose of i.v. pantoprazole (20, 40, 80, or 120 mg), i.v. famotidine (20 mg), or saline placebo. The variables measured were onset of response (time until acid output fell to < 10 mEq/h), duration of response (time acid output remained < 10 mEq/h), and cumulative acid output over 24 h.

RESULTS

All doses of i.v. pantoprazole produced a dose-dependent suppression of acid output to < 10 mEq/h. Single i.v. doses of pantoprazole, 80 and 120 mg, suppressed acid output by > 90% in all subjects for < or = 21 h and had an onset of action of < 1 h.

CONCLUSIONS

Intravenous pantoprazole has a rapid onset and a clear dose-related effect, with a significantly longer duration of action than that of i.v. famotidine.