Dexlansoprazole: A proton pump inhibitor with a dual delayed-release system

The Effect of Dexlansoprazole on Gastroesophageal Reflux Disease: A Systematic Review and Meta-Analysis

This systematic review and meta-analysis evaluated the efficacy of dexlansoprazole (a proton pump inhibitor-PPI) in resolving heartburn, reflux, and other symptoms and complications resulting from gastroesophageal reflux disease (GERD). The study followed PRISMA 2020 and was registered in PROSPERO (CRD42020206513). The search strategy used MeSH and free terms appropriately adapted for each database. Only randomized clinical trials (RCTs) were included. The Cochrane tool (RoB 2.0) was used to assess the risk of bias, and the certainty of evidence was rated using GRADE. Ten RCTs were included. Dexlansoprazole outperformed the placebo and other PPIs in the resolution of heartburn and reflux symptoms in patients with GERD, with benefits during and after treatment, especially in those with moderate and severe symptoms. The meta-analyses indicated that dexlansoprazole at doses of 30 and 60 mg had more 24 h heartburn-free days and nights compared to the placebo medications; no difference was reported between dexlansoprazole at doses of 30 and 60 mg in heartburn-free nights. A low bias risk and a moderate certainty of evidence were observed. This review confirms the therapeutic effect of dexlansoprazole (placebo-controlled) and its improvements in GERD symptoms compared to another PPI. However, the interpretation of the results should be carried out cautiously due to the small number of included studies and other reported limitations.

Benzimidazole based hybrids against complex diseases: A catalogue of the SAR profile

The fused heterocyclic ring system has been recognized as a privileged structure that is used as a template in medicinal chemistry for drug discovery. Benzimidazole is one of the common scaffolds found in several natural products such as histidine, purines, and an integral part of vitamin B12. This hetero-aromatic bicyclic ring system acts as a pharmacophore in various drugs of therapeutic interest and has a broad spectrum of activity. Literature reports suggest that diversely substituted benzimidazoles possess distinct pharmacological profiles with multi-targeting potential, thereby, an indispensable anchor for the development of novel therapeutic agents against complex diseases such as cancer, malaria, inflammatory disorders, microbial diseases, hypertension, etc. Thus, lots of efforts have been diverted towards exploring the therapeutic potential of benzimidazoles. Despite great efforts made by the research community, still, some multi-factorial diseases continue to progress due to their complex pathophysiology. Under these sets of circumstances, there is a need to explore this nucleus for hybrid designing with multi-targeting potential against complex diseases. Benzimidazole-based hybrids have been reported to treat multifactorial diseases, making it a scaffold of interest for various pharmaceutical companies and research groups. In this write-up, we shed light on the recent pharmacological profiles, various designing strategies, and structure-activity relationships (SAR) of different benzimidazole-based hybrids.

Development of Dexlansoprazole Delayed-Release Capsules, a Dual Delayed-Release Proton Pump Inhibitor

Proton pump inhibitors (PPIs) are widely used for treating acid-related disorders. For an "ideal PPI," achieving maximal absorption and sustaining pharmacodynamic effects through the 24-h dosing cycle are critical features. Dexlansoprazole offers a relevant case study on how an improved PPI was developed capitalizing on the rational optimization of a precursor molecule-in this case, using lansoprazole as a starting point, leveraging its chemical properties on pharmacokinetics, and exploring optimized formulations. Dexlansoprazole is the R(+)-enantiomer of lansoprazole and shows stereoselective differences in absorption and metabolism compared with the racemic mixture of lansoprazole. The formulation was further refined to use pulsate-type granules with enteric coating to withstand acidic gastric conditions, while allowing prolonged absorption in the proximal and distal small intestine. As a result, the dual delayed-release formulation of dexlansoprazole has a plasma concentration-time profile characterized by 2 distinct peaks, leading to an extended duration of therapeutic plasma drug concentrations compared with the conventional delayed-release lansoprazole formulation. The dual delayed-release formulation maintains plasma drug concentrations longer than the lansoprazole delayed-release formulation at all doses.

Bioavailability of dexlansoprazole delayed-release capsule granules when administered via nasogastric tube or orally via syringe

Objective

To assess the effect of route of administration on the bioavailability of dexlansoprazole 60 mg delayed-release capsule granules.

Methods

One open-label, Phase I, single-dose, 3-period crossover study was conducted in healthy adults. The bioavailability of Dexilant^® (dexlansoprazole) after dexlansoprazole capsule granules were mixed with water and administered via 16 French nasogastric tube or orally via syringe was compared to administration of the intact capsule in the fasted state, swallowed with water. Blood samples were collected before and after dosing to determine dexlansoprazole pharmacokinetic parameter estimates and plasma concentrations.

Results

Similar values for area under the plasma concentration-time curve and observed maximum plasma concentration were achieved when the dexlansoprazole 60 mg capsule was administered as the intact capsule or when the granules were mixed with water and administered via nasogastric tube or orally via syringe. The primary endpoints of maximum plasma concentration and area under the plasma concentration-time curve demonstrated bioequivalence when assessing these alternative routes of administration. Most adverse events were rated as mild and were comparable irrespective of administration route.

Conclusion

Systemic exposure to dexlansoprazole was equivalent regardless of administration route. The dexlansoprazole capsule was well tolerated.

Industry Payments to Physicians and Prescriptions of Brand-Name Proton-Pump Inhibitors

OBJECTIVE

To characterize the association between industry payments and prescriptions of 2 brand-name proton-pump inhibitors (PPIs).

STUDY DESIGN

Cross-sectional retrospective.

SETTING

Physicians nationwide.

SUBJECTS AND METHODS

We identified all physicians receiving industry payments for Dexilant and Nexium 2014-2015 from the Open Payments database. We linked this to records of prescriptions for PPIs paid for by Medicare Part D these same years and compared the proportion of prescriptions written for Dexilant and Nexium in industry-compensated vs nonindustry compensated physicians. The number and dollar amount of payments were associated with the rate of drug prescriptions.

RESULTS

We identified 254,452 physicians prescribing PPIs; 8586 and 2766 physicians received industry payments for Dexilant and Nexium, respectively. A total of 5052 of 7876 (64%) physicians compensated for Dexilant prescribed Dexilant vs 39,778 of 246,571 (16%) noncompensated physicians ( P < .001). For Nexium, 2525 of 2654 (95%) compensated physicians prescribed Nexium, compared to 123,913 of 252,067 (49%) noncompensated physicians. For both Dexilant and Nexium, there was a significant correlation between the number (ρ = 0.22, P < .001 and ρ = 0.12, P < .001) and dollar amount (ρ = 0.22, P < .001 and ρ = 0.13, P < .001) of payments and the percentage of prescriptions written for the compensated drug. Industry payments for Nexium remained associated with rate of prescription even after generic esomeprazole became available.

CONCLUSION

Both the number and dollar amount of industry payments were associated with increased prescriptions for both Dexilant and Nexium. Although unable to show causality, this study suggests that industry payments may increase physician prescriptions of costly, brand-name drugs.

Dexlansoprazole: delayed-release orally disintegrating tablets for the treatment of heartburn associated with non-erosive gastroesophageal reflux disease and the maintenance of erosive esophagitis

Gastroesophageal reflux disease (GERD) is a common condition afflicting millions of patients, whose prevalence continues to rise owing to the aging population and increasing burden of comorbid conditions, such as obesity. Currently, the mainstay of therapy for GERD is treatment with proton pump inhibitors (PPIs), which have proven efficacy, safety, and tolerability. Despite this, a considerable number of patients have refractory symptoms to PPI therapy. Dexlansoprazole is a new addition to the class of PPIs, which has a unique dual delayed drug release system, which aims to address the current limitations of acid suppressive therapy by offering extended acid suppression and improved ease of administration. Areas covered: This manuscript covers the pharmacokinetics, pharmacodynamics, clinical efficacy, and regulatory approval of dexlansoprazole. Additionally, there is further discussion concerning the current market settings and the potential future impact of dexlansoprazole. Expert commentary: Overall, dexlansoprazole offers benefits in its ease of administration and proven efficacy in the healing, maintenance of erosive esophagitis, and symptomatic non-erosive GERD. Long-term, dexlansoprazole will likely find a niche market among patients who fail other acid suppressive therapy or who desire simplified administration for compliance concerns, but will likely come at a higher out of pocket expense than comparable generic PPIs.

Potassium-competitive acid blockers: Advanced therapeutic option for acid-related diseases

Acid-related diseases (ARDs), such as peptic ulcers and gastroesophageal reflux disease, represent a major health-care concern. Some major milestones in our understanding of gastric acid secretion and ARD treatment reached during the last 50years include 1) discovery of histamine H₂-receptors and development of H₂-receptor antagonists, 2) identification of H⁺,K⁺-ATPase as the parietal cell proton pump and development of proton pump inhibitors (PPIs), and 3) identification of Helicobacter pylori (H. pylori) as the major cause of peptic ulcers and development of effective eradication regimens. Although PPI treatments have been effective and successful, there are limitations to their efficacy and usage, i.e. short half-life, insufficient acid suppression, slow onset of action, and large variation in efficacy among patients due to CYP2C19 metabolism. Potassium-competitive acid blockers (P-CABs) inhibit H⁺,K⁺-ATPase in a reversible and K⁺-competitive manner, and exhibit almost complete inhibition of gastric acid secretion from the first dose. Many pharmaceutical companies have tried to develop P-CABs, but most of their clinical development has been discontinued due to safety concerns or a similar efficacy to PPIs. Revaprazan was developed in Korea and was the first P-CAB approved for sale. Vonoprazan, approved in 2014 in Japan, has a completely different chemical structure and higher pKa value compared to other P-CABs, and exhibits rapid onset of action and prolonged control of intragastric acidity. Vonoprazan is an effective treatment for ARDs that is especially effective in healing reflux esophagitis and for H. pylori eradication. P-CABs, such as vonoprazan, promise to further improve the management of ARDs.

High-dose extended-release lansoprazole (dexlansoprazole) and amoxicillin dual therapy for Helicobacter pylori infections

BACKGROUND

Helicobacter pylori infections have become increasingly difficult to treat.

AIM

To examine whether amoxicillin and high-dose dexlansoprazole would reliably achieve an H. pylori eradication rate of ≥90%.

METHODS

An open-label prospective pilot study of H. pylori eradication in treatment-naïve subjects with active H. pylori infection (positive by two tests).

THERAPY

amoxicillin 1 g and dexlansoprazole 120 mg each twice a day at approximately 12-hour intervals for 14 days. Success was accessed by urea breath test. An effective therapy was defined as a per-protocol treatment success of 90% or greater; treatment success of 80% or less was prespecified as an unacceptable result.

RESULTS

After 13 subjects were entered (12 men, one woman; average age of 54 years), the prespecified stopping rule of six treatment failures was achieved (i.e., the 95% confidence interval excluded achieving the required 90% success rate even if the proposed study of 50 completed patients were entered) and enrollment was stopped. Per-protocol and intention-to-treat treatment success were both 53.8%; (7/13); 95% CI = 25-80%. Compliance was 100%. Three patients (23%) reported side effects, all of which were mild and none interrupted therapy.

CONCLUSION

Theoretically, dual PPI plus amoxicillin should reliably eradicate H. pylori provided nearly neutral intragastric pH can be maintained. Clearly, dexlansoprazole, despite being administered at high dose and twice a day (i.e., total daily dose 240 mg), failed to achieve an intragastric milieu consistent with dual PPI plus amoxicillin therapy being an effective anti-H. pylori regimen.

Indirect comparison of randomised controlled trials: comparative efficacy of dexlansoprazole vs. esomeprazole in the treatment of gastro-oesophageal reflux disease

BACKGROUND

Dexlansoprazole is a new proton pump inhibitor (PPI) with a dual delayed-release system. Both dexlansoprazole and esomeprazole are an enantiomer of lansoprazole and omeprazole respectively. However, there is no head-to-head trial data or indirect comparison analyses between dexlansoprazole and esomeprazole.

AIM

To compare the efficacy of dexlansoprazole with esomeprazole in healing erosive oesophagitis (EO), the maintenance of healed EO and the treatment of non-erosive reflux disease (NERD).

METHODS

Randomised Controlled Trials (RCTs) comparing dexlansoprazole or esomeprazole with either placebo or another PPI were systematically reviewed. Random-effect meta-analyses and adjusted indirect comparisons were conducted to compare the treatment effect of dexlansoprazole and esomeprazole using a common comparator. The relative risk (RR) and 95% confidence interval (CI) were calculated.

RESULTS

The indirect comparisons revealed significant differences in symptom control of heartburn in patients with NERD at 4 weeks. Dexlansoprazole 30 mg was more effective than esomeprazole 20 mg or 40 mg (RR: 2.01, 95% CI: 1.15-3.51; RR: 2.17, 95% CI: 1.39-3.38). However, there were no statistically significant differences between the two drugs in EO healing and maintenance of healed EO. Comparison of symptom control in healed EO was not able to be made due to different definitions used in the RCTs.

CONCLUSIONS

Adjusted indirect comparisons based on currently available RCT data suggested significantly better treatment effect in symptom control of heartburn in patients with NERD for dexlansoprazole against esomeprazole. No statistically significant differences were found in other EO outcomes. However, these study findings need to be interpreted with caution due to small number of studies and other limitations.

Current pharmacological management of gastroesophageal reflux disease

Gastroesophageal reflux disease (GERD), a common disorder with troublesome symptoms caused by reflux of gastric contents into the esophagus, has adverse impact on quality of life. A variety of medications have been used in GERD treatment, and acid suppression therapy is the mainstay of treatment for GERD. Although proton pump inhibitor is the most potent acid suppressant and provides good efficacy in esophagitis healing and symptom relief, about one-third of patients with GERD still have persistent symptoms with poor response to standard dose PPI. Antacids, alginate, histamine type-2 receptor antagonists, and prokinetic agents are usually used as add-on therapy to PPI in clinical practice. Development of novel therapeutic agents has focused on the underlying mechanisms of GERD, such as transient lower esophageal sphincter relaxation, motility disorder, mucosal protection, and esophageal hypersensitivity. Newer formulations of PPI with faster and longer duration of action and potassium-competitive acid blocker, a newer acid suppressant, have also been investigated in clinical trials. In this review, we summarize the current and developing therapeutic agents for GERD treatment.