On-demand proton pump inhibitor therapy in patients with gastro-oesophageal reflux disease

Cost minimization of on-demand maintenance therapy with proton pump inhibitors in nonerosive gastroesophageal reflux disease

On-demand proton pump inhibitor maintenance therapy is one of the suggested strategies for patients with nonerosive gastroesophageal reflux disease who achieve symptom remission after 4 weeks of continuous treatment. This review evaluates the difference in cost and quality of life of six on-demand proton pump inhibitor maintenance strategies in patients with nonerosive gastroesophageal reflux disease. This was performed by decision analysis and Markov modeling of costs (from the perspective of the healthcare service and society) and utility up to 12 months. Median utility scores associated with each proton pump inhibitor ranged from 0.731 to 0.745 quality-adjusted life years and were not statistically different. Annual expected cost, however, was statistically different among the different drugs and the following cost-minimization ranking was obtained for median costs to the healthcare service and society, respectively: rabeprazole (euro 181, euro 295), pantoprazole (euro 223, euro 341), lansoprazole (euro 249, euro 370), omeprazole 10 mg (euro 297, euro 412), esomeprazole (euro 295, euro 419) and omeprazole 20 mg (euro 405, euro 528). Unit cost of proton pump inhibitors was the major determinant of cost to the healthcare service, while the number of productivity days lost due to symptoms was the major determinant of cost to society. In Italy, on-demand use of rabeprazole for maintenance therapy of nonerosive gastroesophageal reflux disease incurs the least cost in comparison with the other proton pump inhibitors evaluated.

Asia-Pacific consensus on the management of gastroesophageal reflux disease: update

BACKGROUND AND AIMS

Since the publication of the Asia-Pacific GERD consensus in 2004, more data concerning the epidemiology and management of gastroesophageal reflux disease (GERD) have emerged. An evidence based review and update was needed.

METHODS

A multidisciplinary group developed consensus statements using the Delphi approach. Relevant data were presented, and the quality of evidence, strength of recommendation, and level of consensus were graded.

RESULTS

GERD is increasing in frequency in Asia. Risk factors include older age, male sex, race, family history, higher socioeconomic status, increased body mass index, and smoking. Symptomatic response to a proton pump inhibitor (PPI) test is diagnostic in patients with typical symptoms if alarm symptoms are absent. A negative pH study off therapy excludes GERD if a PPI test fails. The role for narrow band imaging, capsule endoscopy, and wireless pH monitoring has not yet been undefined. Diagnostic strategies in Asia must consider coexistent gastric cancer and peptic ulcer. Weight loss and elevation of head of bed improve reflux symptoms. PPIs are the most effective medical treatment. On-demand therapy is appropriate for nonerosive reflux disease (NERD) patients. Patients with chronic cough, laryngitis, and typical GERD symptoms should be offered twice daily PPI therapy after excluding non-GERD etiologies. Fundoplication could be offered to GERD patients when an experienced surgeon is available. Endoscopic treatment of GERD should not be offered outside clinical trials.

CONCLUSIONS

Further studies are needed to clarify the role of newer diagnostic modalities and endoscopic therapy. Diagnostic strategies for GERD in Asia must consider coexistent gastric cancer and peptic ulcer. PPIs remain the cornerstone of therapy.

Rabeprazole is equivalent to omeprazole in the treatment of erosive gastro-oesophageal reflux disease. A randomised, double-blind, comparative study of rabeprazole and omeprazole 20 mg in acute treatment of reflux oesophagitis, followed by a maintenance open-label, low-dose therapy with rabeprazole

BACKGROUND

Previous studies have shown similar effects of rabeprazole and omeprazole, when used at the same dose in the treatment of reflux oesophagitis. However, such studies have been conducted as superiority studies but interpreted as equivalence ones.

AIM

To properly assess the comparative efficacy of rabeprazole and omeprazole in inducing complete endoscopic healing and symptom relief in patients with reflux oesophagitis.

METHODS

Patients (n=560) with Savary-Miller grade I-III reflux oesophagitis were randomised in a double-blind, double-dummy fashion to rabeprazole or omeprazole 20 mg once daily for 4-8 weeks. Then, patients endoscopically healed and symptomatically relieved were openly maintained with rabeprazole 10 mg or 2x10 mg once daily (in the event of clinical and/or endoscopic relapse) for a maximum of 48 weeks.

RESULTS

After 4-8 weeks of treatment, healing (primary end-point) was observed in 228/233 (97.9%) patients in the rabeprazole group and in 231/237 (97.5%) in the omeprazole one (equivalence effect demonstrated by p<0.0001 at Blackwelder test and an upper confidence limit at 97.5% of 0.023). However, rabeprazole was faster in inducing heartburn relief than omeprazole (2.8+/-0.2 versus 4.7+/-0.5 days of therapy to reach the first day with satisfactory heartburn relief, p=0.0045 at log-rank test). In the maintenance phase, 15.2% of patients had an endoscopic and/or clinical relapse.

CONCLUSION

Rabeprazole is equivalent to omeprazole in healing reflux oesophagitis, but shows a faster activity on reflux symptoms in the early treatment phase.

Systematic review: the efficacy of intermittent and on-demand therapy with histamine H2-receptor antagonists or proton pump inhibitors for gastro-oesophageal reflux disease patients

AIM

To perform a systematic review on the efficacy of intermittent and on-demand therapy with either histamine H2-receptor antagonists or proton pump inhibitors for patients with erosive oesophagitis or symptomatic heartburn.

METHOD

We conducted randomized-controlled trials of non-continuous therapy in gastro-oesophageal reflux disease patients.

RESULTS

Fourteen studies met inclusion criteria. Because of variation in outcome measures statistical pooling of results was not possible. Results were analysed qualitatively. Four studies evaluated intermittent therapy of treatment 3 days a week with omeprazole 20 mg or daily with ranitidine which were not efficacious compared to a daily proton pump inhibitor. Famotidine 10 and 20 mg, ranitidine 75 mg and cimetidine 200 mg were efficacious in five on-demand studies for relief of symptomatic heartburn episodes. In three of four studies, evaluating only non-erosive (endoscopy-negative) gastro-oesophageal reflux disease patients, esomeprazole 20 and 40 mg and omeprazole 10 and 20 mg a day were efficacious using willingness to continue as an endpoint. Lansoprazole 30 mg and omeprazole 20 mg maintained symptom control in 60-70% of healed oesophagitis patients.

CONCLUSIONS

Intermittent proton pump inhibitor or H2-receptor antagonist therapy is not effective in maintaining control in oesophagitis patients. H2-receptor antagonists are effective for relief of heartburn episodes. On-demand proton pump inhibitor therapy may work in a proportion of non-erosive gastro-oesophageal reflux disease patients.

Progress with novel pharmacological strategies for gastro-oesophageal reflux disease

Gastro-oesophageal reflux disease (GORD) is a chronic disorder characterised by an increased exposure of the oesophagus to intragastric contents. Currently, GORD symptoms are maintained under control with antisecretory agents, mainly gastric proton pump inhibitors (PPIs). Although impaired oesophageal motility may partly underlie the pathophysiology of GORD, the use of prokinetic agents has been found to be unsatisfactory. To date, novel pharmacological approaches for GORD are mainly related to the control of transient lower oesophageal sphincter (LOS) relaxations (TLOSRs). The majority of patients with GORD have reflux episodes during TLOSRs, which are evoked by gastric distension, mainly occurring after ingestion of a meal. Patients with reflux disease with normal peristalsis and without or with mild erosive disease could potentially benefit from anti-TLOSR therapy. This therapy might also be of value to treat some severe forms of esophagitis in combination with PPIs. GABA-B-receptor agonists are the most promising class of agents identified so far for TLOSR control. The GABA-B-receptor agonist, baclofen, is the most effective compound in inhibiting TLOSRs in humans. Since baclofen has several CNS adverse effects, novel orally available GABA-B agonists are needed for effective and well tolerated treatment of GORD. Endogenous or exogenous cholecystokinin (CCK) causes a reduction in LOS pressure, an increase in TLOSR frequency and a reduction in gastric emptying. In healthy volunteers and patients with GORD, loxiglumide, a selective CCK1-receptor antagonist, was found to reduce the rate of TLOSRs, although its effect on postprandial acid reflux may be modest. Orally effective CCK antagonists are not marketed to date. The anticholinergic agent atropine, given to healthy volunteers and patients with GORD, markedly reduced the rate of TLOSRs. Because of severe gastrointestinal (and other) adverse effects of anticholinergics, including worsening of supine acid clearance and constipation, it is unlikely that this class of drugs will have a future as anti-TLOSR agents on a routine basis. In spite of their effectiveness in reducing TLOSR rate, untoward adverse effects, such as addiction and severe constipation, currently limit the use of morphine and other opioid mu-receptor agonists. The same applies to nitric oxide synthase inhibitors, which are associated with marked gastrointestinal, cardiovascular, urinary and respiratory adverse effects. Animal studies provide promising evidence for the use of cannabinoid receptor 1 agonists, by showing potent inhibition of TLOSRs in the dog, thus opening a new route for clinical investigation in humans. A better understanding of TLOSR pathophysiology is a necessary step for the further development of novel drugs effective for anti-reflux therapy.

Les nouveaux inhibiteurs de la pompe à protons, un progrès dans la prise en charge des maladies acido-peptiques ?

EFFECTS AND INCONVENIENCIES OF THE OLDER PRODUCTS: The proton pump inhibitors (PPIs) are now universally considered the treatment of choice for management of gastric-acid-related diseases, mainly gastro-oesophageal reflux disease (GERD). These drugs share similar properties: general structure, acid-activation step, covalent binding to the proton pump of the gastric parietal cell via the production of covalent disulphide bonds, relatively stable inhibition of H+,K+-ATPase. However, the older PPIs (omeprazole, lansoprazole et pantoprazole) have notable limitations. These drugs exhibit substantial interpatient variability and may have significant interactions with other drugs. These first-generation PPIs also do not achieve a rapid and sustained suppression of gastric acid, leading to the development of new acid-pump antagonists. The new-generation PPIs, esomeprazole and rabeprazole, offer several pharmacokinetic advantages: lower oxidative hepatic metabolism rate via the CYP 2C19 reducing the activity variations due to genetic polymorphisms and decreasing the risk of significant drug-drug interactions (advantages mainly for rabeprazole), lower metabolic clearance of esomeprazole (S-enantiomer of omeprazole) increasing plasma concentrations and acid suppression of this new PPI, higher accumulation of rabeprazole in the parietal cell due to its higher pKa. Gastric pH studies and therapeutic trials have demonstrated significant advantages of esomeprazole and rabeprazole compared with the older PPIs, which omeprazole is the prototype: a greater inhibition of acid secretion, a more rapid onset of action to provide reflux symptoms relief over 24 hours with lower GERD-related cost for rabeprazole, a sustained acid suppression, cost-effectiveness advantages for esomeprazole in the healing and maintenance of erosive esophagitis compared with lansoprazole, reduced potential for clinically significant drug-drug interactions with rabeprazole compared with omeprazole and esomeprazole. Due to their properties, esomeprazole and rabeprazole are the best candidates for "on demand" treatment of GERD.