We prospectively conducted virtual bioequivalence (VBE) trials under fasted conditions to guide a clinical trial design and candidate selection for a model drug with a long elimination half-life. We combined biopredictive dissolution methods that mimic gastric motility with innovative biopharmaceutical modeling, enabling suitability checks of crossover and parallel study layouts. Three batches of immediate-release tablets containing 20 mg of vortioxetine were tested against a reference product. Subsequent VBE trials combined a semi-mechanistic biopharmaceutics model with an empirical population approach to describe drug disposition. Parallel VBE included between-subject variability, while the crossover design added interoccasion variability (IOV) at 5% to 15% for the primary PK parameters. Ten trial series were simulated across different sample sizes (12-48), with and without unexplained residual error. Crossover VBE predicted 100% bioequivalence probability for all candidate batches, regardless of the sample size or IOV. In parallel VBE, a maximum bioequivalence probability of 80% was achieved, with at least 60 subjects (30 per arm) required to attain a success probability rate of ≥50%. The selected formulation was bioequivalent with the reference product (90% CI: 97.77-106.05% for Cmax and 96.52-104.32% for AUC0-72h, n = 36). Proposed workflow provides a realistic approximation of bioequivalence study outcome.
Formulation and manufacturing of push-pull osmotic pump (PPOP) tablets are perceived to be complex technological processes. Multiple factors affect drug release kinetics, including polymer grade, drug-to-osmotic agent ratio, membrane characteristics, and manufacturing methods. In this study, we comprehensively investigated how manufacturing techniques impacted glipizide PPOP tablet performance. PPOP tablets comprised push and drug layers manufactured via wet granulation and/or direct compression methods, and different grades of poly(ethylene oxide) (molecular weights 5000 kDa and 4000 kDa) were used in the push layer. Tablets were characterized using biopredictive dissolution tests in the Advanced Modular Platform (AMP) apparatus under both fasted and fed conditions, simulating physiologically relevant mechanical stress events. Magnetic resonance imaging (MRI) was employed to noninvasively monitor tablet hydration, swelling dynamics, and water distribution in the PPOP during hydration. Physiologically based biopharmaceutics modeling (PBBM) was used to simulate glipizide plasma concentrations. All manufactured PPOP tablets released glipizide similarly, following zero-order kinetics, regardless of the manufacturing method and polymer grade in the push layer. Push and drug layer swelling patterns were also comparable. Under simulated mechanical stress conditions, even those exceeding physiological values, all batches maintained consistent release profiles without dose dumping. Only one batch, with both layers directly compressed, showed slightly slower release under fed conditions, but the PBBM model showed a limited influence on the predicted glipizide plasma concentrations. In conclusion, the manufacturing method and polymer grade had minimal impact on PPOP tablet performance, with direct compression providing a viable alternative to wet granulation. PPOP tablets demonstrated robust resistance to physiologically relevant mechanical stress, confirming their prominent role as controlled drug delivery systems.
Current physiologically-based biopharmaceutics modeling (PBBM) neglects the effect of gastrointestinal stress events on the disintegration and dissolution of oral solid dosage forms. Biorelevant dissolution testing can simulate the behavior of drug products under physiological agitation but a workload limits variability examination. In this study, we overcame these deficiencies by inputting dissolution profiles generated by machine-learning (ML) into PBBM-based simulations. Our specific aim was to examine how the varied timing of intragastric stress and housekeeping wave (GET) and fasted stomach pH affect dabigatran exposure from the Pradaxa capsule. Twenty experimental dissolution profiles of dabigatran etexilate from the flow-through apparatus PhysioCell and 1,036 ML-derived profiles representing various gastric motility patterns were a basis for single-dose simulations. A novel timewise dissolution model, which estimates the first-order rate constants at consecutive two-point time intervals, provided an excellent fit to the highly irregular and variable dissolution curves (coefficient of determination ≥ 0.9835, median 0.9992). The time between the onset of dissolution (Tlag), either intragastric stress-related or spontaneous, and the housekeeping wave (GET) systematically impacted the bioavailability of dabigatran. Regardless of gastric emptying rate constant and pH, the dabigatran bioavailability was an increasing sigmoid function of the GET - Tlag difference, with the midpoint around 7 min and plateau of 7-8% after 20 min. The plasma concentrations and bioavailability of dabigatran simulated under varied gastric motility well matched clinical data reported for healthy subjects. We expect that the proposed approach will improve the prediction of the in vivo variability of oral formulations.
A direct oral anticoagulant rivaroxaban fails to prevent stroke and systemic embolism in one-to-several percent of patients with nonvalvular atrial fibrillation (NVAF), but the reasons are unknown. The study used semimechanistic in vitro-in vivo prediction (IVIVP) modeling to explore the reasons for ineffective thrombosis prevention in NVAF patients. Steady-state drug concentrations in plasma were measured at 0 h (C-trough), 3 h (C-3h), and 12 h post-dosing in thirty-four patients treated with 20 mg rivaroxaban daily. The clinical data were compared against "virtual twins" generated with a novel IVIVP model that combined drug dissolution modeling, mechanistic description of gastric drug transit, and population pharmacokinetics defining the variability of drug disposition. The nonresponders had significantly lower C-3h and C-trough than the responders (p < 0.001) and the covariates included in the population pharmacokinetic submodel did not fully explain this difference. Simulations involving varied gastrointestinal parameters in the "virtual twins" revealed that lower small intestinal effective permeability (P-eff), rather than a slower stomach emptying rate, could explain low rivaroxaban exposure in the nonresponders. IVIVP modeling was effectively used for exploring pharmacotherapy failure. Low P-eff,P- found as a major determinant of ineffective rivaroxaban treatment, encourages further research to find (pato) physiological factors influencing suboptimal absorption.
COMPASS is a novel tool for predicting the in vivo similarity of immediate-release oral dosage forms. It bridges the gap between straightforward but purely mathematical f2 factor-based assessment of dissolution profiles and complex physiologically-based pharmacokinetic simulations. This Python-based program uses semi-mechanistic modeling to evaluate the relative differences between key pharmacokinetic endpoint parameters- Cmax and AUC- at variable gastric emptying rate (kGE) and the housekeeping wave time (GET) under fasting conditions. Through a graphical interface the user uploads dissolution results and fits a modified Noyes-Whitney model. Then, after providing the pharmacokinetic absorption and disposition parameters (effective permeability, clearances and distribution volumes) of a given drug, COMPASS generates an interactive report with predicted differences for Cmax and AUC as a function of kGE and GET (3D surface plot), as well as the full plasma concentration-time profiles. Using a dataset comprising 15 formulations (reference and test pairs) containing 11 different drug substances (BCS class I- IV), we determined the measures for discriminating between bioequivalent vs. nonbioequivalent test and reference pairs. We also found that COMPASS-based bioequivalence predictions were similar as those from physiologically-based pharmacokinetic models built in commercially available software. Therefore, COMPASS can support the development of immediate-release dosage forms by fast screening of formulations for bioequivalence/non-bioequivalence, particularly in the early stages, thereby boosting the success rate of clinical trials.
Aim: We aimed to define the influence of P2Y12 polymorphisms (rs6801273, rs2046934, and rs6809699), diabetes, hypertension, obesity, hypercholesterolemia, statins intake, and smoking habit on clopidogrel therapy in patients undergoing percutaneous coronary intervention.Materials & methods: We used PCR-RFLP and PCR-ASO for P2Y12 genotype analysis. The effectiveness of the therapy was measured with the VerifyNow method and defined in platelet reactivity units.Results: Studied polymorphisms had no statistically significant influence on PRU before (PRU0) and 6 months (PRU6) after the procedure. H1/H1 diabetic carriers had significantly higher PRU6 values than patients without diabetes. Obese H1/H2 subjects had significantly lower PRU6 values than H1/H2 non-obese carriers.Conclusion: We found that obesity and diabetes may influence the long-term outcome of antiplatelet therapy.
In vivo studies of formulation performance with in vitro and/or in silico simulations are often limited by significant gaps in our knowledge of the interaction between administered dosage forms and the human gastrointestinal tract. This work presents a novel approach for the investigation of gastric motility influence on dosage form performance, by combining biopredictive dissolution tests in an innovative PhysioCell apparatus with mechanistic physiology-based pharmacokinetic modeling. The methodology was based on the pharmacokinetic data from a large (n = 118) cohort of healthy volunteers who ingested a capsule containing a highly soluble and rapidly absorbed drug under fasted conditions. The developed dissolution tests included biorelevant media, varied fluid flows, and mechanical stress events of physiological timing and intensity. The dissolution results were used as inputs for pharmacokinetic modeling that led to the deduction of five patterns of gastric motility and their prevalence in the studied population. As these patterns significantly influenced the observed pharmacokinetic profiles, the proposed methodology is potentially useful to other in vitro-in vivo predictions involving immediate-release oral dosage forms.
Variability of the gastrointestinal tract is rarely reflected in in vitro test protocols but often turns out to be crucial for the oral dosage form performance. In this study, we present a generation method of dissolution profiles accounting for the variability of fasted gastric conditions. The workflow featured 20 biopredictive tests within the physiological variability. The experimental array was constructed with the use of the design of experiments, based on three parameters: gastric pH and timings of the intragastric stress event and gastric emptying. Then, the resulting dissolution profiles served as a training data set for the dissolution process modeling with the machine learning algorithms. This allowed us to generate individual dissolution profiles under a customizable gastric pH and motility patterns. For the first time ever, we used the method to successfully elucidate dissolution properties of two dosage forms: pellet-filled capsules and bare pellets of the marketed dabigatran etexilate product Pradaxa. We showed that the dissolution of capsules was triggered by mechanical stresses and thus was characterized by higher variability and a longer dissolution onset than observed for pellets. Hence, we proved the applicability of the method for the in vitro and in silico characterization of immediate-release dosage forms and, potentially, for the improvement of in vitro-in vivo extrapolation.
Mathematical models that treat the fed stomach content as a uniform entity emptied with a constant rate may not suffice to explain pharmacokinetic profiles recorded in clinical trials. In reality, phenomena such as the Magenstrasse or chyme areas of different pH and viscosity, play an important role in the intragastric drug dissolution and its transfer to the intestine. In this study, we investigated the data gathered in the bioequivalence trial between an immediate-release tablet (Reference) and an orally dispersible tablet (Test) with a poorly soluble weak base drug administered with or without water after a high-fat high-calorie breakfast. Maximum concentrations (Cmax) were significantly greater after administering the Reference product than the Test tablets, despite similar in vitro dissolution profiles. To explain this difference, we constructed a novel semi-mechanistic IVIVP model including a heterogeneous gastric chyme. The drug dissolution in vivo was modeled from the in vitro experiments in biorelevant media simulating gastric and intestinal fluids in the fed state (FEDGAS and FeSSIF). The key novelty of the model was separating the stomach contents into two compartments: isolated chyme (the viscous food content) that carries the drug slowly, and aq_chyme open for rapid Magenstrasse-like routes of drug transit. Drug distribution between these two compartments was both formulation- and administrationdependent, and recognized the respective drug fractions from the clinical pharmacokinetic data. The model's assumption about the nonuniform mixing of the API with the chyme, influencing differential drug dissolution and transit kinetics, led to simulating plasma concentration profiles that reflected well the variability observed in the clinical trial. The model indicated that, after administration, the Reference product mixes to a greater extent with aq_chyme, where the released drug dissolves better and transfers faster to the intestine. In conclusion, this novel approach underlines that diverse gastric emptying of different oral dosage forms may significantly impact pharmacokinetics and affect the outcomes of bioequivalence trials.
Biorelevant dissolution tests of oral solid dosage forms open the gate to valid in vitro-in vivo predictions (IVIVP). A recently developed apparatus, PhysioCell, allows mimicking the fluid flow and pressure waves occurring in the human fasted stomach. In this work, we used the PhysioCell to perform IVIVP for vortioxetine immediate-release (IR) tablets: the originator (Brintellix) and generic product candidates (VORTIO). The dissolved drug was monitored in the gastric (StressCell) and intestinal (Collection Vessel) compartments that contained biorelevant media. Simulated intermittent gastric stress at 15 min and "housekeeping wave" at 30 min increased the dissolution of Brintellix formulations only. A mechanistic model that best described the observations involved the first-order tablet disintegration with a stress-induced enhancement for Brintellix, dissolution of solid particles in the StressCell, and drug transfer to the Collection Vessel. Then, a semi-mechanistic pharmacokinetic model with dissolution parameters as inputs simulated vortioxetine plasma concentrations in healthy volunteers after single and multiple dosing of Brintellix. Despite different dissolution characteristics, VORTIO provided similar concentration profiles to the originator. In conclusion, PhysioCell dissolution tests, combined with semi-mechanistic IVIVP, can be successfully used to develop IR dosage forms exhibiting gastric stress-related effects.
Virtual bioequivalence trial (VBE) simulations based on (semi)mechanistic in vitro-in vivo (IVIV) modeling have gained a huge interest in the pharmaceutical industry. Sophisticated commercially available software allows modeling variable drug fates in the gastrointestinal tract (GIT). Surprisingly, the between-subject and inter-occasion variability (IOV) of the distribution volumes and clearances are ignored or simplified, despite substantially contributing to varied plasma drug concentrations. The paper describes a novel approach for IVIV-based VBE by using population pharmacokinetics (popPK). The data from two bioequivalence trials with a poorly soluble BCS class II drug were analyzed retrospectively. In the first trial, the test drug product (biobatch 1) did not meet the bioequivalence criteria, but after a reformulation, the second trial succeeded (biobatch 2). The popPK model was developed in the Monolix software (Lixoft SAS, Simulation Plus) based on the originator's plasma concentrations. The modified Noyes-Whitney model was fitted to the results of discriminative biorelevant dissolution tests of the two biobatches and seven other reformulations. Then, the IVIV model was constructed by joining the popPK model with fixed drug disposition parameters, the drug dissolution model, and mechanistic approximation of the GIT transit. It was used to simulate the drug concentrations at different IOV levels of the primary pharmacokinetic parameters and perform the VBE. Estimated VBE success rates for both biobatches well reflected the outcomes of the bioequivalence trials. The predicted 90% confidence intervals for the area under the time-concentration curves were comparable with the observed values, and the 10% IOV allowed the closest approximation to the clinical results. Simulations confirmed that a significantly lower maximum drug concentration for biobatch 1 was responsible for the first clinical trial's failure. In conclusion, the proposed workflow might aid formulation screening in generic drug development.
The physiologically relevant dissolution apparatuses simulate various aspects of gastrointestinal physiology and help to understand and predict the in vivo behavior of an oral dosage form. In this paper, we present and characterize for the first time a novel bio-relevant dissolution apparatus - PhysioCell®;. We evaluated the impact of several factors on the hydrodynamic conditions in the key vessel of the apparatus - the StressCell. We observed that the medium flow rate, but not the glass beads' size or amount, significantly influenced the dissolution rate. The relationship was disproportional: the increase in the flow rate from 4.6 to 9.0 mL/min reduced the dissolution time of 85% (T85) of the NaCl tablet by 46%, but from 134 to 300 mL/min decreased the T85 only by 24%. At the same time, the contractions of the StressCell's elastic walls promoted the content mixing and enhanced the dissolution rate of the paracetamol tablets: even very rare mixing contractions (1 per 10 min) decreased the T85 over twofold for the flow rate of 8 mL/min. In conclusion, the hydrodynamic conditions in the StressCell affect the dissolution of solid dosage forms and the understanding of these effects is crucial for modeling physiologically-based test conditions in the novel apparatus. Combinations of the unique PhysioCell®;features - adjustable medium flow, temperature control, controllable pH gradients and predefined mechanical agitation - can create a set of dissolution test scenarios for characterization of oral dosage forms and, in the future, making the in vitro-in vivo predictions. Graphical Abstract.
Gastric mechanical stress often impacts drug dissolution from solid oral dosage forms, but in vitro experiments cannot recreate the substantial variability of gastric motility in a reasonable time. This study, for the first time, combines a novel dissolution apparatus with the design of experiments (DoE) and machine learning (ML) to overcome this obstacle. The workflow involves the testing of soft gelatin capsules in a set of fasted-state biorelevant dissolution experiments created with DoE. The dissolution results are used by an ML algorithm to build the classification model of the capsule’s opening in response to intragastric stress (IS) within the physiological space of timing and magnitude. Next, a random forest algorithm is used to model the further drug dissolution. The predictive power of the two ML models is verified with independent dissolution tests, and they outperform a polynomial-based DoE model. Moreover, the developed tool reasonably simulates over 50 dissolution profiles under varying IS conditions. Hence, we prove that our method can be utilized for the simulation of dissolution profiles related to the multiplicity of individual gastric motility patterns. In perspective, the developed workflow can improve virtual bioequivalence trials and the patient-centric development of immediate-release oral dosage forms.
Purpose P2Y 12 receptor inhibitors are drugs that decrease the risk of stent thrombosis and lower the long-term risk of non-stent-related myocardial infarction and stroke. They inhibit the binding of adenosine diphosphate (ADP) to the P2Y 12 receptor and effectively reduce platelet reactivity. However, considerable variability in the pharmacodynamics response contributes to a failure of antiplatelet therapy; this phenomenon is especially notorious for older drugs, such as clopidogrel. Some genetic polymorphisms associated with these drugs’ metabolic pathway, especially in the CYP2C19 gene, can significantly decrease antiplatelet efficacy. There are few reports on the variability stemming from the target of this drug class that is the P2Y 12 receptor itself. Results and conclusion This review summarizes the results of research that focus on the influence of P2Y 12 genetic polymorphisms on the pharmacodynamics and the efficacy of P2Y 12 inhibitors. We found that the conclusions of the studies are unequivocal, and despite several strong candidates, such as G52T (rs6809699) or T744C (rs2046934), they may not be independent predictors of the inadequate response to the drug. Most probably, P2Y 12 genetic polymorphisms contribute to the effect exerted by other gene variants (such as CYP2C19*2/*3/*17), drug interactions, or patient habits, such as smoking. Also, epigenetic modifications, such as methylation or miRNA levels, may play a role in the efficacy of antiplatelet treatment.
Current guidelines suggest radiotherapy as a first-line treatment for prostate cancer, along with prostatectomy, and androgen deprivation therapy. Abiraterone is a first-in-class medicinal product recommended in the treat-ment of metastatic castration resistant prostate cancer (mCRPC) that targets androgen receptors and inhibits systemic synthesis. However, successful therapy with this drug may pose some challenges. It has to be admin-istered as an inactive prodrug -abiraterone acetate. It is also dissolved and absorbed poorly with large inter -individual variability and exhibits considerable food effects. Additionally, the recommended daily dose of the drug is high (1000 mg abiraterone acetate), and the cost of the therapy is burdensome.The following review focuses on the strategies to optimize therapy with abiraterone acetate. First, it sum-marizes current findings on abiraterone pharmacokinetics and accentuates the need for utilizing therapeutic monitoring in clinical practice. Next, it extensively describes the options for improving the low bioavailability of the drug. The two major approaches are the utilization of the positive food effect to increase the exposure and development of supergenerics. The review emphasizes how different formulation approaches lead to increased solubility and impact the outcomes of pre-clinical and clinical trials. The review concludes with a discussion on possible future directions that may lead to the increase of the therapeutic efficacy of abiraterone.
Sustained-release (SR) formulations may appear advantageous in first-in-human (FIH) study of innovative medicines. The newly developed SR matrix tablets require prolonged maintenance of API concentration in plasma and should be reliably assessed for the risk of uncontrolled release of the drug. In the present study, we describe the development of a robust SR matrix tablet with a novel G-protein-coupled receptor 40 (GPR40) agonist for first-in-human studies and introduce a general workflow for the successful development of SR formulations for innovative APIs. The hydrophilic matrix tablets containing the labeled API dose of 5, 30, or 120 mg were evaluated with several methods: standard USP II dissolution, bio-predictive dissolution tests, and the texture and matrix formation analysis. The standard dissolution tests allowed preselection of the prototypes with the targeted dissolution rate, while the subsequent studies in physiologically relevant conditions revealed unwanted and potentially harmful effects, such as dose dumping under an increased mechanical agitation. The developed formulations were exceptionally robust toward the mechanical and physicochemical conditions of the bio-predictive tests and assured a comparable drug delivery rate regardless of the prandial state and dose labeled. In conclusion, the introduced development strategy, when implemented into the development cycle of SR formulations with innovative APIs, may allow not only to reduce the risk of formulation-related failure of phase I clinical trial but also effectively and timely provide safe and reliable medicines for patients in the trial and their further therapy.
Introduction: Depressive disorders are common in older patients, and their prevalence may reach up to 17.1%. Though for older adults, the initial recommended treatment is either life-review treatment or group cognitive-behavioral therapy, a combination of pharmacotherapy with interpersonal psychotherapy is also an option. There are many classes of antidepressants, and some meta-analyses suggest that the efficacy of different antidepressant groups is similar. Therefore, depression treatment in an elderly patient should consider preference, safety, and tolerability. Most reports suggest that SSRIs, such as citalopram, escitalopram, or sertraline, should be proposed as first-time medications. Areas covered: This article discusses the pharmacokinetic and pharmacodynamic properties of vortioxetine, emphasizing the observed differences, benefits, and risks for older patients. Vortioxetine - a multimodal antidepressant drug - was shown to be effective against major depressive disorders in both double-blinded, placebo-controlled trials and open-label studies. Expert opinion: Compared with commonly used antidepressants, vortioxetine appears to have unique properties that may be beneficial for elderly patients. Not only does it enhance cognitive function, but it also has a favorable safety profile.
Development of generic extended-release (ER) formulations is challenging. Especially under fed conditions, the risk of failure in bioequivalence trials is high because of long gastric residence times and susceptibility to food effects. We describe the development of a generic trazodone ER formulation that was aided with a biorelevant dissolution evaluation. Trazodone hydrochloride 300-mg monolithic matrix tablets were dissolved both in USP and EMA compliant conditions and in the StressTest device that simulated both physicochemical and mechanical conditions of the gastrointestinal passage. The final formulation was tested against the originator, Trittico XR 300 mg, in a randomized cross-over bioequivalence trial with 44 healthy volunteers, in agreement with EMA guidelines. Initially developed formulations dissolved trazodone similarly to the originator under standard conditions (f 2 factor above 50), but their dissolution kinetics differed significantly in the biorelevant tests. The formulation was optimized by the addition of low-viscosity hypromellose and mannitol. The final formulation was approved for the bioequivalence trial. Calculated C max were 1.92 ± 0.77 and 1.92 ± 0.63 [μg/mL], AUC 0-t were 27.46 ± 8.39 and 29.96 ± 9.09 [μg∙h/mL], and AUC 0-∞ were 28.22 ± 8.91 and 30.82 ± 9.41 [μg∙h/mL] for the originator and test formulations, respectively. The 90% confidence intervals of all primary pharmacokinetic parameters fell within the 80–125% range. In summary, biorelevant dissolution tests supported successful development of a generic trazodone ER formulation pharmaceutically equivalent with the originator under fed conditions. Employment of biorelevant dissolution tests may decrease the risk of failure in bioequivalence trials of ER formulations.
The original version of this article, published on 30 May 2020 contained a mistake.
ELISA has become a standard analytical tool in the numerous branches of science and industry. Processing of the ELISA results may be a multistep process, often requiring a prior adaptation, using proprietary software, or exporting the results into external internet platforms. It may be problematic in the light of good documentation practices and maintaining good data integrity. In this paper, we present the development and application of the ELISA Tool software. The program is based on a Python scripting programming language and is available under an open-source license. The ELISA Tool allows users to fully control and validate the calculation procedure through a user-friendly graphical user interface. The modular architecture of the software allows its application in other information technology (IT) projects used for data processing in research laboratories. We successfully applied the ELISA Tool for the analysis of real-life samples. The ELISA Tool allowed import of the measurement data, an approximation of the calibration curves with two different algorithms, exploration and diagnostics of the model fit, and generation of the final report with the calculations while maintaining the raw data file unchanged. We report here for the first time the implementation of the idea of full control over data processing, from measured raw data to the final report. We obtained a transparent, open, registered system of data processing control, independent of third parties. The modular and flexible architecture of the created software encourages its further development following the individual demands of the users.