Physiologically Based Biopharmaceutics Modeling for Gefapixant IR Formulation Development and Defining the Bioequivalence Dissolution Safe Space.

Gefapixant is a weakly basic drug which has been formulated as an immediate release tablet for oral administration. A physiologically based biopharmaceutics model (PBBM) was developed based on gefapixant physicochemical properties and clinical pharmacokinetics to aid formulation selection, bioequivalence safe space assessment and dissolution specification settings. In vitro dissolution profiles of different free base and citrate salt formulations were used as an input to the model. The model was validated against the results of independent studies, which included a bioequivalence and a relative bioavailability study, as well as a human ADME study, all meeting acceptance criteria of prediction errors ≤ 20% for both Cmax and AUC.  PBBM was also applied to evaluate gastric pH-mediated drug-drug-interaction potential with co-administration of a proton pump inhibitor (PPI), omeprazole. Model results showed good agreement with clinical data in which omeprazole lowered gefapixant exposure for the free base formulation but did not significantly alter gefapixant pharmacokinetics for the citrate based commercial drug product. An extended virtual dissolution bioequivalence safe space was established.  Gefapixant drug product batches are anticipated to be bioequivalent with the clinical reference batch when their dissolution is > 80% in 60 minutes. PBBM established a wide dissolution bioequivalence space as part of assuring product quality.

Pharmacokinetics and pharmacodynamics of intravenously and subcutaneously administered pantoprazole in sheep (Ovis aries).

Abomasal ulcers are recognized in sheep of all ages, but research regarding therapeutic interventions is limited. Proton Pump Inhibitors (PPIs) such as pantoprazole, are clinically used with a paucity of evidence regarding efficacy in mature sheep. Intravenous and subcutaneously administered pantoprazole dosed at 1.0 mg/kg in adult sheep will increase the pH of abomasal fluid compared to pre-administration baseline. The objectives were to assess the effect of pantoprazole, after single and multiple administration, on abomasal fluid pH in adult sheep. A third objective was to describe the pharmacokinetic parameters of IV and SC pantoprazole. Four clinically healthy adult Southdown ewes previously fitted with a gastrostomy tube in the abomasum were utilized in this randomized, 2-way cross-over trial. Ewes received pantoprazole (1.0 mg/kg) as a single and 3-dose regimen (every 24 hours). After a 10 day washout period the reverse treatment was applied. Blood for analysis of pantoprazole concentration was collected intermittently for 24 hours, and abomasal fluid pH was measured at intervals for a 96-hour period. The pH of the abomasal fluid was higher in pantoprazole treatments for up to 24 hours after dosing. Following intravenous administration of pantoprazole to study ewes, elimination half-life, volume of distribution, and clearance of pantoprazole was estimated as 3.29 hours, 0.35 L/kg, and 65.26 mL/hr/kg respectively. After subcutaneous dosing, maximum concentration, time to maximum concentration, half-life of elimination, and volume of distribution, were estimated as 2604 ng/mL, 0.55 hours, 2.48 hours, and 0.37 L/kg. Additionally, the bioavailability was estimated as 83.33%. Pantoprazole administered IV or SC may be useful for treatment or prevention of abomasal ulcers in adult sheep.

Modeled Hepatic/Plasma Exposures of Omeprazole Prescribed Alone in Cytochrome P450 2C19 Poor Metabolizers Are Likely Associated with Hepatic Toxicity Reported in a Japanese Adverse Event Database.

Omeprazole, a gastric acid pump inhibitor, is repeatedly administered and is oxidatively metabolized mainly by polymorphic cytochrome P450 2C19. The prescribed dosage of omeprazole was discontinued or reduced in 47 of the 135 patients who received omeprazole alone in this survey, as recorded in the Japanese Adverse Drug Event Report database. The days to onset of omeprazole-related disorders were 3-4 d (median) and 16 d for intravenous 20-40 mg and oral 20 mg daily doses, respectively, in 34 patients for whom relevant data were available. The maximum plasma concentration of omeprazole was pharmacokinetically modeled after a single oral 40-mg dose in P450 2C19-defective poor metabolizers and was 2.4-fold higher than that in extensive metabolizers. The modeled area under the hepatic concentration curves of omeprazole in P450 2C19 poor metabolizers after virtual daily 40-mg doses for 7 d was 5.2-fold higher than that in the extensive metabolizers. Omeprazole-induced P450 2C19 (approx. 2-fold), resulting in increased hepatic intrinsic clearance in repeated doses, was considered after the second day. Virtual plasma/hepatic exposure estimated using pharmacokinetic modeling in subjects with P450 2C19 poor metabolizers indicated that these exposure levels virtually estimated could be one of causal factors for unexpected hepatic disorders induced by prescribed omeprazole, such as those resulting from drug interactions with repeatedly co-administered medicines.

Integrated models of population pharmacokinetics and exposure response to optimize dosage regimen for anaprazole sodium in duodenal ulcer.

Anaprazole sodium enteric-coated tablet is a novel proton pump inhibitor which has been approved for the treatment of duodenal ulcer. The aim of this study is to provide reliable information for the design of an optimal dosage regimen. Population pharmacokinetics and exposure-response models were integrated to evaluate the pharmacokinetic parameters and covariates of Anaprazole and its metabolite M21-1, and subsequently provided dosage suggestions based on clinical trials and simulation data. A pharmacokinetic model incorporating two-compartment for the parent drug and one-compartment for the metabolite, with both first-order and zero-order mixed absorption was used to describe the pharmacokinetics of Anaprazole and M21-1. Age emerged as a significant covariate affecting the elimination rate constant of M21-1, with clearance decreasing as age advances. No correlation was observed between the pharmacokinetics of Anaprazole or M21-1 and the adverse reactions under the current dosages. BMI might be the influence factor of the mild gastrointestinal adverse reactions. Meanwhile, Anaprazole had a good healing rate (94.0 %) in duodenal ulcer patients and the exposure-response analysis indicated that the cured results were not influenced by the exposure parameters of parent drug or metabolite. In conclusion, the drug is safe when dosing between 20 and 100 mg once a day.

Influence of novel CYP2C-haplotype on proton pump inhibitor pharmacokinetics in children.

In this brief report, we provide an analysis of the influence of a novel CYP2C haplotype (CYP2C:TG) on proton pump inhibitor (PPI) pharmacokinetics (PK) in children. The CYP2C:TG haplotype has been proposed to be associated with increased CYP2C19 activity. We sought to determine if this CYP2C:TG haplotype resulted in similar alterations in metabolism for proton pump inhibitors, which are primarily metabolized by CYP2C19. In a cohort of 41 children aged 6-21 participating in a PPI pharmacokinetic study, effects of the CYP2C:TG allele were assessed by fitting two linear regression models for each of the six PK outcomes assessed, the second of which accounted for the presence of the CYP2C:TG allele. The difference in R2 values between the two models was computed to quantify the variability in the outcome that could be accounted for by the CYP2C:TG allele after adjustment for the CYP2C19 genotype. We found the CYP2C:TG haplotype to have no measurable additive impact on CYP2C19-mediated metabolism of PPIs in vivo in older children and adolescents. The findings of this study do not support the clinical utility of routine testing for the CYP2C:TG haplotype to guide PPI dose adjustments in children.

Pharmacokinetic Interactions Between Tegoprazan and the Combination of Clarithromycin, Amoxicillin and Bismuth in Healthy Chinese Subjects: An Open-Label, Single-Center, Multiple-Dosage, Self-Controlled, Phase I Trial.

BACKGROUND: Tegoprazan is a potassium-competitive acid blocker that inhibits gastric acid and which may be used for eradicating Helicobacter pylori. This study focuses on the pharmacokinetic interaction and safety between tegoprazan and the combination of clarithromycin, amoxicillin and bismuth in healthy Chinese subjects. METHODS: An open-label, three-period, single-center, multiple-dosage, single-sequence, phase I trial was conducted in 22 healthy subjects. In period 1, the subjects took tegoprazan 50 mg twice daily for 7 days, and in period 2 they were administered clarithromycin 500 mg, amoxicillin 1000 mg and bismuth potassium citrate 600 mg twice daily for 7 days (days 14-20). Tegoprazan, clarithromycin, amoxicillin and bismuth potassium citrate were then administered in combination for 7 days (days 21-27) in period 3. Blood samples were collected up to 12 h after the last dose of each period. Safety assessments were performed in each period. RESULTS: The geometric mean ratios (GMRs) [90% confidence interval (CI)] of maximum plasma concentration at steady state (Cmax,ss) and area under the plasma concentration-time curve over the dosing interval (AUCτ) at steady state were 195.93% (175.52-218.71%) and 287.54% (263.28-314.04%) for tegoprazan and 423.23% (382.57-468.22%) and 385.61% (354.62-419.30%) for tegoprazan metabolite M1, respectively. The GMRs (90% CI) of Cmax,ss and AUCτ were 83.69% (77.44-90.45%) and 110.30% (102.74-118.41%) for clarithromycin, 126.25% (114.73-138.93%) and 146.94% (135.33-159.55%) for 14-hydroxyclarithromycin, 75.89% (69.73-82.60%) and 94.34% (87.94-101.20%) for amoxicillin, and 158.43% (125.43-200.11%) and 183.63% (156.42-215.58%) for bismuth, respectively. All reported adverse events were mild. The frequency of adverse events during the coadministration stage was not higher than that during the single- or triple-drug administration stages. CONCLUSION: The plasma exposure of tegoprazan, M1, 14-hydroxyclarithromycin and bismuth was increased after the coadministration of tegoprazan, clarithromycin, amoxicillin and bismuth. The coadministration exhibited favorable safety and tolerability. CLINICAL TRIALS REGISTRATION: CTR20230643.

Proton Pump Inhibitors Do Not Affect the Bioavailability of a Novel Liquid Formulation of Levothyroxine.

OBJECTIVE: This study evaluates the impact of a representative proton pump inhibitor (PPI) (omeprazole), administered simultaneously or staggered, on the pharmacokinetics of levothyroxine (LT4) solution (Tirosint-SOL). METHODS: This was a randomized, 3-way crossover, comparative bioavailability study in 36 healthy adults under fasting conditions. Omeprazole 40 mg delayed-release capsule was administered once daily from Day 1 to 6 (mornings, Treatment-A; evenings, Treatment-B; none, Treatment-C) to increase and stabilize gastric pH. In the morning of Day 5, a single dose of LT4 solution 600 mcg was administered. Blood samples were collected 0 to 48 hours post-LT4 administration. Noncompartmental pharmacokinetic parameters were calculated for total serum thyroxine using baseline-corrected data. Maximum concentration (Cmax) and area under the concentration-time curve (AUC0-48) were included in an analysis of variance to obtain geometric mean ratios and 90% confidence intervals. RESULTS: For both comparisons (A/C and B/C), geometric mean ratios and 90% confidence intervals for all parameters were within the equivalence boundaries (80%-125%), indicating bioequivalence: for A/C, AUC0-48 98.98% [94%-104%], and Cmax 91.68% [87%-97%]; for B/C, AUC0-48 98.94% [95%-103%], and Cmax 94.90% [90%-100%]. Median Tmax (time associated with Cmax) was similar across treatments. CONCLUSION: This study demonstrated that Tirosint-SOL bioavailability is unaffected by coadministration of a representative PPI, given simultaneously or staggered by about 12 hours, compared to administration of LT4 solution alone. For hypothyroid patients on PPI therapy, administration of LT4 solution may reduce variations in thyroid stimulating hormone levels related to intermittent use of acid-reducing drugs and consequently the need for dose adjustments.

A comprehensive review on potential drug-drug interactions of proton pump inhibitors with antidiabetic drugs metformin and DPP-4 inhibitors.

A drug interaction is a condition in which two or more drugs are taken at the same time. Type 2 diabetes mellitus is a significant contributor to polypharmacy. Proton pump inhibitors (PPIs) are often prescribed in combination with metformin or DPP-4 inhibitors (sitagliptin, saxagliptin, linagliptin, and alogliptin) or a combined dose of metformin and DPP-4 inhibitor to treat gastritis in diabetic patients. This review article mainly focused on evaluating the potential drug-drug interactions (DDIs) between PPIs (i.e. esomeprazole, lansoprazole, omeprazole, pantoprazole, and rabeprazole) with metformin and PPIs with DPP-4 inhibitors. The findings demonstrated the existence of pharmacokinetic and pharmacodynamic DDIs between the aforementioned PPIs with metformin and DPP-4 inhibitors, which could impact the biological activities (i.e., hypoglycemia) of these drugs. Moreover, this review suggested that esomeprazole could be the best drug in the PPI group to be prescribed simultaneously with metformin and DPP-4 inhibitors, as most of the antidiabetic drugs of this study did not show any interaction with esomeprazole. The findings of this study also revealed that both antidiabetic drugs and PPIs could have positive interactions as PPIs have the potential to lessen the gastrointestinal side effects of metformin and DPP-4 inhibitors. To achieve the greatest therapeutic impact with the fewest side effects, careful dose control of these drugs is required. So, more extensive research on both human and animal subjects are needed to ascertain the veracity of this hypothesis.

Effect of Food and a Proton-Pump Inhibitor on the Absorption of Encorafenib: An In Vivo-In Vitro-In Silico Approach.

Encorafenib is a kinase inhibitor indicated for the treatment of patients with BRAF mutant melanoma and BRAF mutant metastatic colorectal cancer. To understand the effect of food and coadministration with a proton-pump inhibitor (PPI), in vitro, in vivo, and in silico data were generated to optimize the clinical dose, evaluate safety, and better understand the oral absorption process under these conditions. Study 1 evaluated the effect of food on the plasma pharmacokinetics, safety, and tolerability after a single oral dose of encorafenib 100 mg. Study 2 evaluated the same end points with coadministration of encorafenib and rabeprazole (PPI perpetrator). The in vitro gastrointestinal TIM-1 model was used to investigate the release of encorafenib and the amount available for absorption under different testing conditions (fasted, fed, and with the use of a PPI). The fasted, fed, and PPI states were predicted for the encorafenib commercial capsule in GastroPlus 9.8. In study 1, both AUCinf and AUClast decreased by 4% with the administration of a high-fat meal. The Cmax was 36% lower than with fasted conditions. All 3 exposure parameters in study 2 (AUCinf, AUClast, and Cmax) had mean changes of <10% when encorafenib was coadministered with a PPI. Using the in vitro gastrointestinal simulator TIM-1, the model demonstrated a similar release of drug, as the bioaccessible fraction, in the 3 conditions was equal (≥80%), predicting no PPI or food effect for this drug formulation. The modeling in GastroPlus 9.8 demonstrated complete absorption of encorafenib when formulated as an amorphous solid dispersion. To obtain these results, it was crucial to integrate the amorphous solubility of the drug that shows a 20-fold higher solubility at pH 6.8 compared with crystalline solubility. The increased amorphous solubility is likely the reason no PPI effect was observed compared with fasted state conditions. The prolongation in gastric emptying in the fed state resulted in delayed plasma Tmax for encorafenib. No dose adjustment is necessary when encorafenib is administered in the fed state or when coadministered with a PPI. Both the TIM-1 and physiologically based pharmacokinetic model results were consistent with the observed clinical data, suggesting that these will be valuable tools for future work.

Pharmacokinetic Interaction of Anaprazole, Amoxicillin and Clarithromycin after Single-Dose Simultaneous Administration and the Effect of Adding Bismuth on Their Pharmacokinetics in Healthy Male Chinese Subjects.

BACKGROUND AND OBJECTIVE: Helicobacter pylori-positive ulcers are treated with a proton pump inhibitor (PPI) + two antibiotics with/without bismuth. The objective of this study was to investigate the pharmacokinetic interaction of the novel PPI anaprazole, amoxicillin and clarithromycin with/without bismuth. METHODS: This single-centre, randomised, open-label phase 1 pharmacokinetic study included healthy Chinese male participants, comprising two cohorts (cohort 1, 4 × 4 crossover design; cohort 2, 2 × 2 crossover design). In cohort 1, 24 participants received four treatment cycles with a different treatment in each cycle; the washout period between cycles was 9 days. Participants were randomly assigned to one of the following four treatment sequences (1:1:1:1): anaprazole sodium enteric-coated tablet 20 mg monotherapy, amoxicillin 1000 mg monotherapy, clarithromycin 500 mg monotherapy, and a three-drug combination (anaprazole 20 mg, amoxicillin 1000 mg and clarithromycin 500 mg). During each treatment cycle, study drugs were administered twice daily for four consecutive days and once in the morning on the fifth day. Cohort 2 participants were administered a single dose of the three-drug combination and a single dose of a four-drug combination (three-drug combination + bismuth 0.6 g) with a washout period of 11 ± 2 days between treatments. Blood samples were collected for pharmacokinetic analysis. RESULTS: Twenty-nine of 32 enrolled participants (cohort 1, n = 24; cohort 2, n = 8) completed the study. There were no significant differences in exposure or time to reach maximum concentration (Tmax) between each single drug or the three-drug combination (cohort 1) or between the three- and four-drug combinations (cohort 1) for any of the drugs/metabolites. CONCLUSIONS: Dose adjustments for individual drugs are not necessary with combined dosing of anaprazole, amoxicillin, clarithromycin and bismuth.

Bioequivalence and Relative Bioavailability Studies to Assess a New Acalabrutinib Formulation That Enables Coadministration With Proton-Pump Inhibitors.

Acalabrutinib is a Bruton tyrosine kinase (BTK) inhibitor approved to treat adults with chronic lymphocytic leukemia, small lymphocytic lymphoma, or previously treated mantle cell lymphoma. As the bioavailability of the acalabrutinib capsule (AC) depends on gastric pH for solubility and is impaired by acid-suppressing therapies, coadministration with proton-pump inhibitors (PPIs) is not recommended. Three studies in healthy subjects (N = 30, N = 66, N = 20) evaluated the pharmacokinetics (PKs), pharmacodynamics (PDs), safety, and tolerability of acalabrutinib maleate tablet (AT) formulated with pH-independent release. Subjects were administered AT or AC (orally, fasted state), AT in a fed state, or AT in the presence of a PPI, and AT or AC via nasogastric (NG) route. Acalabrutinib exposures (geometric mean [% coefficient of variation, CV]) were comparable for AT versus AC (AUCinf 567.8 ng h/mL [36.9] vs 572.2 ng h/mL [38.2], Cmax 537.2 ng/mL [42.6] vs 535.7 ng/mL [58.4], respectively); similar results were observed for acalabrutinib's active metabolite (ACP-5862) and for AT-NG versus AC-NG. The geometric mean Cmax for acalabrutinib was lower when AT was administered in the fed versus the fasted state (Cmax 255.6 ng/mL [%CV, 46.5] vs 504.9 ng/mL [49.9]); AUCs were similar. For AT + PPI, geometric mean Cmax was lower (371.9 ng/mL [%CV, 81.4] vs 504.9 ng/mL [49.9]) and AUCinf was higher (AUCinf 694.1 ng h/mL [39.7] vs 559.5 ng h/mL [34.6]) than AT alone. AT and AC were similar in BTK occupancy. Most adverse events were mild with no new safety concerns. Acalabrutinib formulations were comparable and AT could be coadministered with PPIs, food, or via NG tube without affecting the PKs or PDs.

An update on drug-drug interactions associated with proton pump inhibitors.

INTRODUCTION: Proton pump inhibitors (PPIs) block the gastric H/K-ATPase, therefore inhibiting acid gastric secretion, leading to an increased pH (>4). They account for an extremely high number of prescriptions worldwide. Numerous drug-drug interactions have been described with PPIs, but all the described interactions do not have clinical significance. AREAS COVERED: This review will discuss the latest updates on drug-drug interactions with PPIs, focusing on the last 10-year publications in the following areas: anti-infective agents, anticancer drugs, antiplatelet agents and anticoagulants, and antidiabetics. EXPERT OPINION: Although pharmacokinetic interactions of PPIs have been described with many drugs, their clinical relevance remains controversial. However, given the extremely high number of people being treated with PPIs, clinicians should remain vigilant for interactions that may be clinically significant and require dose adjustment or therapeutic monitoring. Interestingly, not all PPIs have the same pharmacokinetic and pharmacodynamic profile, with some having a strong potential to inhibit CYP2C19, such as omeprazole, esomeprazole, and lansoprazole, while others, pantoprazole, rabeprazole, and dexlansoprazole, are weak CYP2C19 inhibitors. These may be preferred depending on co-prescribed treatments.In addition, new formulations have been developed to prevent some of the gastric pH-dependent drug interactions and should be evaluated in further large-scale prospective comparative studies.

Bioavailability of acalabrutinib suspension delivered via nasogastric tube in the presence or absence of a proton pump inhibitor in healthy subjects.

AIMS: Acalabrutinib, a selective Bruton tyrosine kinase inhibitor, is approved for the treatment of mantle cell lymphoma and chronic lymphocytic leukaemia. Many critically ill patients are unable to swallow and need oral medications to be delivered via a nasogastric (NG) tube. Furthermore, critically ill patients are typically administered proton-pump inhibitors (PPIs) to prevent stress ulcers. Concomitant administration with PPIs reduces acalabrutinib exposure and is not currently recommended. To evaluate acalabrutinib in subjects co-administered with PPIs who require NG delivery, a phase 1, open-label, randomized, crossover, single-dose study was conducted in healthy subjects. METHODS: The study assessed the relative bioavailability of an acalabrutinib suspension-in regular, degassed Coca-Cola-administered via NG tube (Acala-NG) versus the pharmacokinetics (PK) of an acalabrutinib capsule administered orally with water. In addition, the PPI effect was evaluated by comparing the PK following Acala-NG in the presence or absence of rabeprazole. RESULTS: Exposure of acalabrutinib and its active metabolite (ACP-5862) were comparable following administration of Acala-NG versus the oral capsule (Geo mean ratio, % ref [90% confidence interval, CI]: acalabrutinib AUCinf : 103 [93-113]; Cmax : 144 [120-173]). In addition, exposure was similar following administration of Acala-NG with and without a PPI (Geo mean ratio, % ref [90% CI]: acalabrutinib AUCinf : 105 [79-138]; Cmax : 95 [66-137]). No safety or tolerability concerns were observed, and all adverse events were mild and resolved without treatment. CONCLUSIONS: Acala-NG with or without a PPI is safe and well-tolerated without impeding bioavailability.

Controlled release floating drug delivery system for proton pump inhibitors lansoprazole: In-vitro, In-vivo floating and pharmacokinetic evaluation.

Lansoprazole (LPZ) show poor bioavailability because of first pass effect and absorption factors. The floating delivery systems could reduce fluctuations in plasma drug concentration through maintaining desirable plasma drug concentration. The objective of present study was to enhance bioavailability despite first pass effect through continuous availability of drug from floating system. Gum tragacanth (GT) and itaconic acid (IA) based floating hydrogels (FH) were synthesized. Parameters optimized were; microwave radiation exposure time, pH, GT:IA ratio and concentration of the glutaraldehyde. Optimized FH were evaluated for entrapment efficiency (% EE), in-vitro release, FTIR, SEM, and in- vitro and in-vivo floating study. Finally, pharmacokinetic was evaluated in ulcer-induced SD rats. Grafting percentage, swelling ratio and %EE of LPZ was 115%, Ì´250% and 90%, respectively. Microwave radiation exposure time, pH of reaction medium, GT:IA ratios and cross linker concentration were 2 min, pH 5, ratios 2:1 and 0.02%, respectively. The optimized FH showed acceptable floating behavior. The X-ray images revealed that hydrogels remained floated over gastric contents up to 24 hours. The in-vitro release and pharmacokinetics revealed availability of LPZ upto to 24h in-vitro and in ulcer-induced SD rats, respectively. The present hydrogels based floating system of lansoprazole is capable to extend the gastric residence time upto 24 hours.

Utility of the 13 C-pantoprazole breath test as a CYP2C19 phenotyping probe for children.

The 13 C-pantoprazole breath test (PAN-BT) is a safe, noninvasive, in vivo CYP2C19 phenotyping probe for adults. Our objective was to evaluate PAN-BT performance in children, with a focus on discriminating individuals who, according to guidelines from the Clinical Pharmacology Implementation Consortium (CPIC), would benefit from starting dose escalation versus reduction for proton pump inhibitors (PPIs). Children (n = 65, 6-17 years) genotyped for CYP2C19 variants *2, *3, *4, and *17 received a single oral dose of 13 C-pantoprazole. Plasma concentrations of pantoprazole and its metabolites, and changes in exhaled 13 CO2 (termed delta-over-baseline or DOB), were measured 10 times over 8 h using high performance liquid chromatography with ultraviolet detection and spectrophotometry, respectively. Pharmacokinetic parameters of interest were generated and DOB features derived using feature engineering for the first 180 min postadministration. DOB features, age, sex, and obesity status were used to run bootstrap analysis at each timepoint (Ti ) independently. For each iteration, stratified samples were drawn based on genotype prevalence in the original cohort. A random forest was trained, and predictive performance of PAN-BT was evaluated. Strong discriminating ability for CYP2C19 intermediate versus normal/rapid metabolizer phenotype was noted at DOBT30 min (mean sensitivity: 0.522, specificity: 0.784), with consistent model outperformance over a random or a stratified classifier approach at each timepoint (p < 0.001). With additional refinement and investigation, the test could become a useful and convenient dosing tool in clinic to help identify children who would benefit most from PPI dose escalation versus dose reduction, in accordance with CPIC guidelines.

Pharmacokinetic Drug-Drug Interaction Study of Omecamtiv Mecarbil With Omeprazole, a Proton Pump Inhibitor, in Healthy Subjects.

Omecamtiv mecarbil (OM) is a novel cardiac myosin activator in development for the treatment of heart failure (HF) with reduced ejection fraction. OM is administered as a 25-, 37.5-, or 50-mg modified-release formulation in patients with HF. Proton pump inhibitors are one of the most commonly prescribed drugs in this patient population. Given the potential for coadministration of both drugs in patients with HF, we evaluated the potential for omeprazole to affect the pharmacokinetics of OM in an open-label study in 14 healthy subjects. Subjects received a single 50-mg dose of OM on day 1, followed by 40-mg once-daily doses of omeprazole on days 4 to 8. On day 9, a single 40-mg dose of omeprazole was administered first and immediately followed by 50-mg of OM. Blood samples were collected up to 144 hours after dosing following administration of OM on days 1 and 9 to characterize plasma concentrations of OM. The ratios of the geometric least-square means (90% confidence intervals) of OM coadministered with omeprazole compared to OM alone were 94.5% (81.7%-109.3%), 94.3% (81.5%-109.1%), and 101.2% (95.4%-107.3%) for area under the plasma concentration-time curve from time 0 to infinity, area under the plasma concentration-time curve from time 0 to the last measurable concentration, and maximum observed plasma concentration, respectively. Coadministration of OM with omeprazole was not associated with any clinically significant pharmacokinetic drug interactions. Single doses of OM were safe and well tolerated when coadministered with omeprazole.

An analysis of the biopharmaceutical behaviour of proton pump inhibitors with different physicochemical properties.

At present, little information on the biopharmaceutical behaviour of proton pump inhibitors (PPIs) describing their absorption and biodistribution in vivo has been reported because the extreme instability of PPIs in the gastrointestinal environment makes it difficult to analyze such behaviour. In this work, a modified rat in situ intestinal perfusion model was employed to investigate absorption in the gastrointestinal tract and subsequent biodistribution of several PPIs (ilaprazole, esomeprazole and rabeprazole), which have different physicochemical properties. Our data indicated that PPIs exhibited significantly enhanced absorption rates in the whole intestine, including the duodenum, jejunum, ileum and colon, corresponding to the increase in the oil-water partition coefficient (LogP). PPIs and corresponding salt types showed no obvious differences in absorption, implying that solubility changes in the PPI have little effect on its absorption in the gastrointestinal tract. Among these PPIs, ilaprazole presented a more stable intestinal absorption behaviour, as well as more distribution and longer residence time in the stomach by HPLC-MS/MS analysis and radioactivity counts after 14C radiolabelling. These results may be useful information for PPI optimization and oral formulation design.

Effect of Elevated pH on the Commercial Enteric-Coated Omeprazole Pellets Resistance: Patent Review and Multisource Generics Comparison.

Omeprazole is a widely used over-the-counter (20 mg) proton pump inhibitor, usually supplied as oral enteric-coated pellets intended to release at pH 5.5 and higher; however, it is sensitive to acidic pH. The likelihood of elevated gastric pH in practice is very high for patients; thus, the aim of this study was to investigate the effect of elevated pH on the performance of commercial omeprazole pellets. Commercial enteric-coated delayed-release pellets were tested with water uptake-weight loss (WU-WL) test at pH range between 1.2 and 4.5 in addition to "gastric" (pH 1.2 or 4.5) and "intestinal" (pH 7.4) phase dissolution tests. The range of physical characteristics of pellets was determined with a single pellet size and sedimentation time measurement, followed by the application of modified Stokes' Law equation. The coefficient of variation of pellet size and density, and volume-density determination coefficient (R2) as descriptors of coating thickness and microstructure variability, degree of ionisation of enteric polymers, aqueous solubility and molecular weight of plasticisers have been found useful to explain commercial delayed-release pellets behaviour during WU-WL and dissolution test. Investigated commercial delayed-release pellets demonstrated pH-dependent WU-WL results. "Gastric phase" dissolution testing of pellets at pH 4.5 showed the highest omeprazole degradation (48.1%) for Nosch Labs, intermediate values of dose loss (23.4% and 17.1%) for Teva and UQUIFA delayed-release pellets, respectively. Lab Liconsa pellets have been found as the least susceptible (3.2% of dose loss). Additionally, "gastric phase" dissolution test at pH 4.5 significantly influenced omeprazole release during the "intestinal phase". The risk of inadequate therapy associated with intake of investigated enteric-coated delayed-release pellets at elevated gastric pH has been found as minimal for Lab Liconsa and has increased from UQUIFA and Teva to Nosh Labs pellets.

Pharmacokinetics and Pharmacodynamics of Esomeprazole/Sodium Bicarbonate Immediate-Release Capsules in Healthy Chinese Volunteers: A Cross-Over, Randomized Controlled Trial.

INTRODUCTION: Esomeprazole delayed release tablets (ESO) are one of the most effective treatments for acid-related disorders. The purpose of this study is to compare the safety, pharmacokinetics (PK) and pharmacodynamics (PD) of an immediate-release capsule formulation containing esomeprazole 20 mg and sodium bicarbonate 1100 mg (IR-ESO) compared to those of the esomeprazole delayed release tablet 20 mg (ESO). In addition, the impact of CYP2C19 gene polymorphisms on PK and PD was evaluated. METHODS: A single-center, open-label, randomized, 2-treatment, 2-sequence, and 2-period crossover study was conducted in 40 healthy Chinese subjects. Subjects received either IR-ESO or ESO for 5 days. After single- and multiple-dosing administration, blood samples were collected for PK analysis, and intragastric pH was assessed by 24-h pH monitoring. The CYP2C19 gene polymorphisms were analyzed by Sanger sequencing. RESULTS: The geometric mean ratios (90% confidence interval) [GMR (95%CI)] of IR-ESO/ESO for AUCinf [single dose: 103.60% (96.58%, 111.14%), multiple doses: 101.65% (97.88%, 105.57%)] were within the range of 80.00-125.00%. The AUCinf showed an increasing trend between CYP2C19 extensive metabolizer (EM), intermediate metabolizer (IM), and poor metabolizer (PM) after single-dose and multiple-dose administration (p < 0.05). The GMR (95%CI) of IR-ESO/ESO for 24-h integrated gastric acidity from baseline [single dose: 101.07% (96.56%, 105.78%), multiple doses: 101.24% (97.74%, 104.86%)] were within the range of 80.00-125.00%. The percentage changes in 24-h integrated gastric acidity from baseline was significant difference between EM, IM, and PM after single-dose IR-ESO and ESO (p < 0.05). Drugs were all well tolerated, and there were no significant differences in adverse events between IR-ESO and ESO. CONCLUSION: This study showed that IR-ESO can inhibit the secretion of gastric acid rapidly and continuously, and that the PK and PD of IR-ESO are affected by CYP2C19 genotypes. The GMR (95% CI) of IR-ESO/ESO for AUCinf and the percentage changes in 24-h integrated gastric acidity from baseline were all within the range of 80.00-125.00%. TRIAL REGISTRATION: Chinese Clinical Trial Registry: ChiCTR1900024935.

Use of Pharmacogenomics to Guide Proton Pump Inhibitor Therapy in Clinical Practice.

Prescribing the right medication, at the right dose, to the right patient is the goal of every physician. Pharmacogenomic information is an emerging tool that can be used to deliver precision medicine. In this review, we discuss the pharmacogenomics of available PPIs, racial differences of CYP2C19 and how PPI pharmacogenomics affects the treatment of common gastrointestinal diseases. We also provide practical guidance on when to order pharmacogenomic testing, which test to order, and how to modify treatment based on published guidelines.