Lafutidine changes levels of somatostatin, calcitonin gene-related peptide, and secretin in human plasma

Effects of pirenzepine on vonoprazan-induced gastric acid inhibition and hypergastrinemia

BACKGROUND

Compared to proton pump inhibitors, vonoprazan exerts a greater inhibitory effect on gastric acid secretion and is useful for treating acid-related diseases, such as gastro-esophageal reflux disease. However, there is a problem that vonoprazan causes hypergastrinemia, which confers a risk of carcinoid tumor. A previous report demonstrated that pirenzepine, an M1 muscarinic receptor antagonist, enhances the acid inhibitory effects while suppressing hypergastrinemia induced by omeprazole. Here, we examined whether pirenzepine enhances the gastric acid inhibitory effects of vonoprazan without further increasing serum gastrin levels.

METHODS

Eleven healthy volunteers were subjected to 24-h intragastric pH monitoring and serum gastrin measurements on day 7 of three different regimens: pirenzepine 75 mg alone, vonoprazan 10 mg alone, and vonoprazan 10 mg plus pirenzepine 75 mg administered in a randomized crossover fashion.

RESULTS

Median pH 4 holding time ratios (range) achieved with pirenzepine 75 mg, vonoprazan 10 mg, and vonoprazan 10 mg plus pirenzepine 75 mg were 6.9% (2.4-32.8%), 88.4% (54.6-100%), and 84.2% (40.3-100%), respectively. Respective serum gastrin levels were 79 (75-210) pg/ml, 310 (110-870) pg/ml, and 170 (140-930) pg/ml. In cases with hypergastrinemia (gastrin ≥ 200 pg/ml) induced by vonoprazan 10 mg alone, concomitant treatment with pirenzepine significantly reduced serum gastrin levels from 370 to 180 pg/ml (P = 0.028).

CONCLUSION

Although pirenzepine does not enhance acid inhibition, it does improve hypergastrinemia induced by vonoprazan to some extent.

Comparison of effect of an increased dosage of vonoprazan versus vonoprazan plus lafutidine on gastric acid inhibition and serum gastrin

BACKGROUND

Vonoprazan, a novel potassium-competitive acid blocker, elicits potent acid inhibition and hypergastrinemia at a dose of 20 mg. Its recommended maintenance dose for gastro-esophageal reflux disease is 10 mg, which is sometimes insufficient for preventing nocturnal acid breakthrough (NAB). Concomitant use of a histamine 2 receptor antagonist (H2RA) is effective for NAB. However, further acid inhibition by addition of H2RA has concern of hypergastrinemia again. Lafutidine (H2RA) is known to stimulate somatostatin release.

AIMS

The aim of this study is to compare the levels of acid inhibition and serum gastrin attained by addition of lafutidine to vonoprazan 10 mg with levels after a dose increase of vonoprazan from 10 to 20 mg.

METHODS

Thirteen healthy volunteers underwent 24-h intragastric pH monitoring and serum gastrin measurements on day 7 of three different regimens: vonoprazan 10 mg, vonoprazan 10 mg plus lafutidine 10 mg, and vonoprazan 20 mg.

RESULTS

Median pH 4 holding time ratios (range) by vonoprazan 10 mg, vonoprazan 10 mg plus lafutidine 10 mg, and vonoprazan 20 mg were 82% (47-88%), 88% (76-93%), and 99% (95-100%) while those at nighttime from 10 p.m. to 8 a.m. were 94% (29-100%), 100% (95-100%), and 100%, respectively. The incidences of NAB with vonoprazan 10 mg, vonoprazan plus lafutidine, and vonoprazan 20 mg were 38, 8, and 0%, respectively. Respective serum gastrin levels were 420 (173-508), 323 (196-521), and 504 (400-812) pg/ml.

CONCLUSION

Addition of lafutidine 10 mg to vonoprazan 10 mg achieved sufficient acid inhibition, especially at nighttime, without further increase of serum gastrin levels.

Forced degradation of lafutidine and characterization of its non-volatile and volatile degradation products using LC-MS/TOF, LC-MSn and HS-GC-MS

The study involved establishment of the intrinsic degradation behaviour of lafutidine under hydrolytic, oxidative and photolytic conditions.

Randomized controlled trial of effectiveness of lafutidine versus pantoprazole in uninvestigated dyspepsia

OBJECTIVES

Lafutidine is a new H2-blocker in India claimed to be more potent and effective than existing H2-blockers. Proton pump inhibitors (PPIs), by virtue of their mechanism of action, have greater efficacy than H2-blockers in gastric acid suppression. However, clinical trials comparing H2-blockers directly with PPIs are limited. We carried out a head-to-head comparison of the effectiveness of lafutidine versus the PPI pantoprazole in uninvestigated dyspepsia [CTRI/2013/12/004261].

MATERIALS AND METHODS

A prospective, open label, randomized, controlled trial was conducted in a tertiary care hospital. Ambulatory adult patients with dyspepsia, not yet subjected to endoscopy, were recruited if they had at least moderately severe symptoms, defined as a score of ≥ 4 on a 7-point Global Overall Symptom (GOS) Scale. Those with alarm features or significant comorbidity were excluded. Subjects received either once daily lafutidine 10 mg or pantoprazole 40 mg, orally, for 8 weeks. Reflux, dysmotility and pain scores were assessed by Modified Frequency Scale for the Symptoms of Gastroesophageal Reflux Disease (mFSSGERD), and quality of life (QoL) by SF-8 scale. The latter had physical and mental components summarized by physical component summary score (PCS) and a mental component summary score (MCS).

RESULTS

Of 122 patients enrolled, data of 57 on lafutidine and 60 on pantoprazole were analyzed. At 4 weeks, proportion of subjects responding (GOS score ≤ 2) in the two arms (lafutidine 45.61% vs. pantoprazole 48.33%, P = 0.854) or showing symptom resolution (GOS score ≤ 1) (lafutidine 12.28% vs. pantoprazole 5.00%; P = 0.197) were comparable. Similarly at 8 weeks, both responder (lafutidine 52.63% vs. pantoprazole 56.67%; P = 0.712) and symptom resolution proportions (lafutidine 33.33% vs. pantoprazole 30%; P = 0.843) were comparable. Total score on mFSSGERD scale, as well as all its three component scores, and PCS and MCS scores on QoL SF-8 scale showed improvement but no statistically significant difference between the two arms. Tolerability of both drugs was excellent.

CONCLUSIONS

Lafutidine is well-tolerated and there is no clinically worthwhile difference between the two drugs in the empirical treatment of uninvestigated dyspepsia.

Lafutidine 10 mg versus Rabeprazole 20 mg in the Treatment of Patients with Heartburn-Dominant Uninvestigated Dyspepsia: A Randomized, Multicentric Trial

Background. Empirical therapy with antisecretory agents like PPIs and H2RAs has long been the traditional approach in the initial management of uninvestigated dyspepsia. Aim. The objective of the study was to examine relief of dyspepsia with lafutidine, a second-generation H(2)-RA, and rabeprazole and to compare their efficacy. Methods. This was a randomized, open, comparative trial in adult uninvestigated dyspeptic patients, who had at least moderate severity of symptoms, defined as a score of ≥4 on a 7-point global overall symptom (GOS) scale, and were randomized to receive once daily either lafutidine 10 mg or rabeprazole 20 mg for 4 weeks. Results. A total of 236 patients were enrolled, out of which 194 patients were included in the analysis. At the end of week 4, a significant difference was observed for symptom relief (lafutidine 89.90% versus rabeprazole 65.26%, P < .01) and symptom resolution (lafutidine 70.71% versus rabeprazole 25.26%, P < .01). Both the drugs were well tolerated. Conclusion. Both lafutidine and rabeprazole provide symptom relief in patients with heartburn-dominant uninvestigated dyspepsia. The present study confirms the appropriateness of lafutidine as an empiric treatment and superior efficacy for primary care practice patients with dyspepsia.

An open-label, randomized, cross-over bioequivalence study of lafutidine 10 mg under fasting condition

AIM: To assess the relative bioavailability and pharmacokinetic properties of two formulations (test and reference) of Lafutidine 10 mg.

METHODS: The study was performed as an open label, randomized, two-way, two-period, two-treatment, single dose cross-over bioequivalence study, under non-fed condition to compare the pharmacokinetic profiles of the lafutidine formulation manufactured by Emcure Pharmaceuticals Ltd., India using an indigenously developed active pharmaceutical ingredient (API) and the commercially available Stogra^® formulation, of UCB Japan Co., Ltd., Japan. The two treatments were separated by a wash-out period of 5 d. After an overnight fasting period of 10 h, the subjects were administered either the test or the reference medication as per the randomization schedule. Blood samples were collected at intervals up to 24 h, as per the approved protocol. Concentrations of lafutidine in plasma were analyzed by a validated liquid chromatography/tandem mass spectrometry (LC/MS/MS) method, and a non-compartmental model was used for pharmacokinetic analysis. The pharmacokinetic parameters were subjected to a 4-way ANOVA accounting for sequence, subjects, period and treatment. Statistical significance was evaluated at 95% confidence level (P ≥ 0.05).

RESULTS: The mean (± SD) values of the pharmacokinetic parameters (test vs reference) were C_max (265.15 ± 49.84 ng/mL vs 246.79 ± 29.30 ng/mL, P < 0.05), Area under the curve (AUC)_(0-t) (1033.13 ± 298.74 ng.h/mL vs 952.93 ± 244.07 ng.h/mL, P < 0.05), AUC_(0-∞) (1047.61 ± 301.22 ng.h/mL vs 964.21 ± 246.45 ng.h/mL, P < 0.05), and t_½(1.92 ± 0.94 h vs 2.05 ± 1.01 h, P < 0.05). The 90% confidence intervals (CI) for the test/reference ratio of mean C_max, AUC_(0-t), and AUC_(0-∞) were within the acceptable range of 80.00 to 125.00. The mean times (± SD) to attain maximal plasma concentration (t_max) of lafutidine were 0.95 ± 0.24 h vs 1.01 ± 0.29 h (P < 0.05) for the test and the reference formulations respectively. Both the formulations were well tolerated.

CONCLUSION: In summary, this study has demonstrated the bioequivalence of the two formulations of lafutidine 10 mg. Hence it can be concluded that the two formulations can be used interchangeably in clinical settings.

Lafutidine prevents low-dose aspirin and loxoprofen induced gastric injury: a randomized, double-blinded, placebo controlled study

BACKGROUND AND AIM

The concomitant use of non-steroidal anti-inflammatory drugs is a risk factor for low-dose aspirin (LDA)-associated upper gastrointestinal toxicity. Lafutidine is an H2-receptor antagonist with gastroprotective activity, produced by acting on capsaicin-sensitive afferent neurons. To evaluate the preventive effect of lafutidine on gastric damage caused by LDA alone and by the combination of both LDA and loxoprofen, we conducted a clinical study using healthy volunteers.

METHODS

A randomized, double-blinded, placebo-controlled, crossover study was carried out. Sixteen healthy volunteers without Helicobacter pylori infection were randomly assigned to two groups. Both groups received 81 mg of aspirin once daily for 14 days (on days 1 to 14) and 60 mg of loxoprofen three times daily for the last 7 days (on days 8 to 14). Placebo or 10 mg of lafutidine was administered twice daily for 14 days in each group. After a 2-week washout period, placebo and lafutidine were crossed over. Endoscopic findings of gastric mucosal damage were evaluated according to the modified Lanza score.

RESULTS

The mean modified Lanza score was 2.19 ± 1.06 (SD) for aspirin plus placebo as compared with 0.50 ± 0.77 for aspirin plus lafutidine (P < 0.001), and 3.00 ± 1.56 for aspirin plus loxoprofen and placebo as compared with 1.25 ± 1.37 for aspirin plus loxoprofen and lafutidine (P < 0.01).

CONCLUSIONS

The addition of loxoprofen to LDA increases gastric mucosal damage. Standard-dose lafutidine significantly prevents gastric mucosal damage induced by LDA alone or LDA plus loxoprofen in H. pylori-negative volunteers. Larger controlled studies are needed to strengthen these findings.

[Guidelines of treatment for non-bleeding peptic ulcer disease]

Over the past century, since the introduction of non steroidal anti-inflammatory drugs (NSAID), antacid, histamine H2-receptor antagonists (H2RA), proton pump inhibitors (PPI), and discovery of Helicobacter pylori infection, the paradigm of peptic ulcer disease has changed with marked decrease in morbidity and mortality. However, peptic ulcer disease still occupies a position as a major health problem with increase of aged population and NSAIDs usage. In daily general practice, the management of peptic ulcer disease is directed according to the presence of bleeding or not. For non-bleeding peptic ulcer disease, proper acid suppression and the correction of underlying causes such as Helicobacter pylori infection and NSAID use is the main stay of treatment. Though a complete understanding of pathophysiology and a perfect treatment strategy are still a challenge, this guideline aims to provide practical recommendations based on evidences or consensus of experts through in-depth literature review and expert meeting.

Pharmacokinetic and Pharmacodynamic Properties of Lafutidine after Postprandial Oral Administration in Healthy Subjects: Comparison with Famotidine

Lafutidine, a histamine H(2)-receptor antagonist, inhibits gastric acid secretion during the daytime, however, the relationship between the plasma concentration and the drug response remains unclear. The aim of this study was to compare the pharmacokinetic and pharmacodynamic properties of lafutidine and famotidine following postprandial oral administration. After a lafutidine tablet (10 mg), famotidine tablet (20 mg), or water only (control) was administered, blood samples were taken and intragastric pH was measured. The plasma concentrations of lafutidine and famotidine were determined by HPLC, and the median intragastric pH values per 30 min were used as the degrees of gastric acid suppression. Data were analyzed based on a one-compartment pharmacokinetic model and a sigmoid E(max) pharmacodynamic model. Lafutidine plasma concentrations rapidly increased after administration; famotidine required some time to increase the plasma concentrations, requiring an absorption lag time in the pharmacokinetic model. Between the plasma concentration and DeltapH (the difference in intragastric pH by the drug vs. control), lafutidine showed an anticlockwise hysteresis loop which indicated equilibration delay between the plasma concentration and effect site, requiring an effect site compartment in the pharmacodynamic model; famotidine showed more parallel relationship. These results indicated that the pharmacokinetic and pharmacodynamic properties of lafutidine after postprandial oral administration were different from those of famotidine at least 4.5 h after dosing.

Calcitonin gene-related peptide and somatostatin releases correlated with the area under the lafutidine concentration–time curve in human plasma

OBJECTIVE

To examine the effects of the histamine H(2)-receptor antagonist, lafutidine, at clinical dosage (10 mg tablet after a standardized meal) on plasma levels of the gastrointestinal peptides, calcitonin gene-related peptide (CGRP), somatostatin and gastrin.

METHODS

Six healthy male volunteers ate a standardized meal, and received either lafutidine orally at a dose of 10 mg or water only (control). Blood samples were taken before and up to 4 h after the drug administration. Plasma lafutidine concentrations were determined by high pressure liquid chromatography. Pharmacokinetic analysis of lafutidine was performed using one-compartmental model. The levels of immunoreactive substances of plasma CGRP, somatostatin and gastrin were measured by enzyme immunoassay, and the amount of peptide release was calculated by the trapezoidal method. Lafutidine significantly increased plasma CGRP levels at 1, 1.5, 2.5 and 4 h and the total amount of CGRP release (192 +/- 14.0 pg.h/mL) compared with the control group (128 +/- 21.5 pg.h/mL).

RESULTS

Lafutidine significantly increased the plasma somatostatin levels at 1 and 1.5 h, and the total amount of somatostatin released (107 +/- 18.2 pg.h/mL) compared with the control (78.4 +/- 7.70 pg.h/mL). The area under the drug concentration-time curve (AUC) from 0 to 4 h after administration correlated well with the Delta-CGRP and Delta-somatostatin release but not with total amount of gastrin released. However, plasma gastrin levels were significantly elevated at 1.5 h after drug administration.

CONCLUSION

Lafutidine at clinical dosage increases plasma CGRP and the somatostatin. The amounts released correlated with the AUC of lafutidine in humans. These results suggest that the increased release of CGRP and somatostatin may contribute to its gastroprotective and anti-acid secretory effect.

Lafutidine, a newly developed antiulcer drug, elevates postprandial intragastric pH and increases plasma calcitonin gene-related peptide and somatostatin concentrations in humans: comparisons with famotidine

Lafutidine, a newly developed histamine H(2)-receptor antagonist, inhibits daytime (i.e., postprandial) as well as nighttime gastric acid secretion in clinical studies. It also has gastroprotective activity that particularly affects mucosal blood flow in rats. This study focused on the efficacy of lafutidine on plasma concentrations of gastrointestinal peptides in humans. Six healthy male volunteers aged 23-32 years without Helicobacter pylori infection were orally administered either 10 mg lafutidine, 20 mg famotidine, or water only (control) 30 min after a standard meal (650 kcal). Plasma concentrations of lafutidine and famotidine were highest from 90 to 150 min after administration. Intragastric pH was elevated after both lafutidine and famotidine compared with the control. Plasma concentrations of calcitonin gene-related peptide (CGRP) and somatostatin were significantly increased after lafutidine at 60 and 90 min. We concluded that lafutidine increases plasma concentrations of CGRP and somatostatin in humans, which may result in inhibition of postprandial acid secretion and gastroprotective activity.

Determination of lafutidine in human plasma by high-performance liquid chromatography-electrospray ionization mass spectrometry: application to a bioequivalence study

A rapid, sensitive and specific high-performance liquid chromatography-electrospray ionization mass spectrometry (LC/ESI-MS) method was developed and validated for the first time to determine the concentration of lafutidine in human plasma. After the addition of diazepam (the internal standard, IS) and 1 M sodium hydroxide solution to 0.5-ml plasma sample, lafutidine was extracted from plasma with n-hexane : isopropanol (95 : 5, v/v). The organic layer was evaporated and the residue was redissolved in 200-microl mobile phase. The analyte was chromatographically separated on a prepacked Shimadzu Shim-pack VP-ODS C(18) column (250 x 2.0 mm i.d.) using a mixture of methanol-water (20 mM CH(3)COONH(4)) = 80 : 20 (v/v) as mobile phase. Detection was performed on a single quadrupole mass spectrometer using an electrospray ionization interface and the selected-ion monitoring (SIM) mode. The method showed excellent linearity (r = 0.9993) over the concentration range of 5-400 ng/ml and had good accuracy and precision. The within- and between-batch precisions were within 10% relative standard deviation. The limit of detection was 1 ng/ml. The validated LC/ESI-MS method has been successfully applied to the bioequivalence study of lafutidine in 24 healthy male Chinese volunteers.

Helicobacter pylori infection prevents the occurrence of the tolerance phenomenon of histamine H2 receptor antagonists

BACKGROUND

The attenuated anti-secretory activity of H2 receptor antagonists (H2RA) during continuous administration is referred to as the tolerance phenomenon. However, it is not clarified whether Helicobacter pylori infection affects the occurrence of tolerance to H2RA. It is also not clarified whether the tolerance phenomenon occurs to a new H2RA, lafutidine.

AIM

To investigate the occurrence of the tolerance phenomenon in subjects with and without H. pylori infection during the continuous administration of lafutidine and famotidine.

SUBJECTS AND METHODS

Subjects were 20 healthy male volunteers (seven H. pylori positive and 13 H. pylori negative cases). All subjects were examined by ambulatory intragastric pH monitoring five times without medication, on the first and 15th day of the administration of 20 mg b.d. famotidine and 10 mg b.d. lafutidine in a cross-over fashion.

RESULTS

The tolerance phenomenon was not observed in H. pylori-positive subjects during the 15-day-long administration of both H2RAs. In contrast, the tolerance phenomenon was observed in H. pylori negative subjects, which has been previously reported.

CONCLUSIONS

This study demonstrated that H. pylori infection affects the tolerance phenomenon during continuous administration of H2RAs.

Lafutidine inhibits Helicobacter pylori-induced interleukin-8 production in human gastric epithelial cells

BACKGROUND AND AIM

Attachment of Helicobacter pylori to gastric epithelial cells leads to the production of chemokines, such as interleukin-8 (IL-8), which in turn activate and recruit neutrophils to the site of infection. Lafutidine [(+/-)-2-(furfurylsulfinyl)-N-(4-(4-(piperidinomethyl)-2-pyridyl)oxy-(Z)-2-butenyl)acetamide] is a new type of antiulcer drug that possesses an antisecretory action as well as gastroprotective activity, independent of its antisecretory action. In the present study, we examined the effects of lafutidine on H. pylori-induced IL-8 release and H. pylori adhesion to MKN45 cells.

METHODS

MKN45 cells were stimulated with H. pylori, tumor necrosis factor (TNF)-alpha, or IL-1beta, then IL-6 and IL-8 levels in the culture supernatants were determined with a specific enzyme-linked immunosorbent assay kit.

RESULTS

Lafutidine significantly inhibited both the release of IL-8 induced by H. pylori and the adhesion of H. pylori to cells in a dose-dependent manner. These properties of lafutidine are unrelated to the blockade of histamine H(2)-receptors, because the same effects have not been observed with other H(2)-receptor antagonists, such as cimetidine and famotidine. Lafutidine also significantly inhibited H. pylori-induced IL-6 release. Both TNF-alpha and IL-1beta-induced IL-8 releases, conversely, were little affected by lafutidine up to a concentration of 10(-5) M.

CONCLUSIONS

These results suggest that lafutidine inhibits IL-8 release by inhibiting H. pylori adherence to gastric epithelial cells, indicating a novel mechanism by which lafutidine protects against the mucosal inflammation associated with H. pylori infection.

Effect of Sho-hange-ka-bukuryo-to on Gastrointestinal Peptide Concentrations in the Plasma of Healthy Human Subjects

Sho-hange-ka-bukuryou-to, a traditional Chinese herbal (Kampo) medicine, has been used to treat hyperemesis of pregnancy, nausea and vomiting. Most traditional herbal medicines are prepared from several herbs. For example, Sho-hange-ka-bukuryo-to is prepared from three herbs: Pinelliae Tuber, Zingiberis Rhizoma and Hoelen. Thus, to determine the precise mechanism of the pharmacological effects of Chinese herbal medicines is too difficult. So we have elucidated the effect of some Chinese herbal medicines by examining the change of the plasma levels of brain-gut peptides. In this study, we investigated the effects of Sho-hange-ka-bukuryo-to on the plasma levels of gut-regulated peptides (gastrin, somatostatin, motilin and vasoactive intestinal peptide (VIP)) and gastrointestinal mucosa regulatory neuropeptides (calcitonin gene-related peptide (CGRP) and substance P) in healthy human subjects. A single oral administration of Sho-hange-ka-bukuryo-to caused significant increases in plasma somatostatin-, CGRP- and substance P-immunoreactive substance (IS) levels, compared with a placebo group. Transient elevation of gastrin-IS levels in the placebo group was inhibited by the administration of Sho-hange-ka-bukuryo-to, but the medicine showed no effects on plasma motilin- or VIP-IS levels. In conclusion, these results might indicate that the pharmacological action of Sho-hange-ka-bukuryo-to is closely related to changes in gastrin-, somatostatin-, CGRP- and substance P-IS levels in human plasma.

Comparison of the effects of hange-shashin-to and rikkunshi-to on human plasma calcitonin gene-related peptide and substance P levels

Regarding the gastroprotective function as a neural emergency system, sensory afferent neurons in the gastrointestinal mucosa regulate neuropeptide (calcitonin gene-related peptide (CGRP), substance P, etc.) levels, and those peptides play various physiological roles. To determine whether the pharmacological effects of Hange-shashin-to and Rikkunshi-to on the gastrointestine are due to changes in gastrointestinal mucosa regulatory peptides levels, we investigated the levels of CGRP-like immunoreactive substances (IS) and substance P-IS in plasma from healthy subjects. A single oral administration of Hange-shashin-to caused significant increases in CGRP-IS (40-60 min) and substance P-IS (60-180 min) levels in the plasma compared with the levels induced by a placebo. Rikkunshi-to and a 5.0 g Pinelliae tuber extract had no significant effect on CGRP-IS and substance P-IS levels. Extract of a 2.5 g Zingiberis rhizoma significantly caused increases in CGRP-IS at 40 min and in substance P-IS at 60 min. These results, in comparison with Kampo medicines, might indicate that the pharmacological actions of Hange-shashin-to closely are related to changes in CGRP-IS and substance P-IS levels, while Zingiberis rhizoma partially might participate in those effects of Hange-shashin-to.