Towards Virtual Bioequivalence Studies for Oral Dosage Forms Containing Poorly Water-Soluble Drugs: A Physiologically Based Biopharmaceutics Modeling (PBBM) Approach.

The objective of the present study was to develop a physiologically based biopharmaceutics (PBBM) approach to predict the bioequivalence of dosage forms containing poorly soluble drugs. Aripiprazole and enzalutamide were used as model drugs. Variations in the gastrointestinal (GI) physiological parameters of fasted humans were taken into consideration in in vitro biorelevant dissolution testing and in an in silico PBBM simulations.

Biowaiver Monograph for Immediate-Release Solid Oral Dosage Forms: Carbamazepine.

Literature relevant to assessing whether BCS-based biowaivers can be applied to immediate release (IR) solid oral dosage forms containing carbamazepine as the single active pharmaceutical ingredient are reviewed. Carbamazepine, which is used for the prophylactic therapy of epilepsy, is a non-ionizable drug that cannot be considered "highly soluble" across the range of pH values usually encountered in the upper gastrointestinal tract. Furthermore, evidence in the open literature suggests that carbamazepine is a BCS Class 2 drug.

Biowaiver Monographs for Immediate Release Solid Oral Dosage Forms: Metformin Hydrochloride.

Data are examined regarding possible waiver of in vivo bioequivalence testing (i.e. biowaiver) for approval of metformin hydrochloride (metformin) immediate-release solid oral dosage forms.

The use of PBPK/PD to establish clinically relevant dissolution specifications for zolpidem immediate release tablets.

Background: Zolpidem is a non-benzodiazepine hypnotic agent which has been shown to be effective in inducing and maintaining sleep in adults and is one of the most frequently prescribed hypnotics in the world. For drugs that are used to treat sleeping disorders, the time to reach the maximum concentration (T) of the drug in plasma is important to achieving a fast onset of action and this must be maintained when switching from one product to another.

Objectives: The main objective of the present work was to create a PBPK/PD model for zolpidem and establish a clinically relevant "safe space" for dissolution of zolpidem from the commercial immediate release (IR) formulation.

Opportunities for Successful Stabilization of Poor Glass-Forming Drugs: A Stability-Based Comparison of Mesoporous Silica Versus Hot Melt Extrusion Technologies.

Amorphous formulation technologies to improve oral absorption of poorly soluble active pharmaceutical ingredients (APIs) have become increasingly prevalent. Currently, polymer-based amorphous formulations manufactured by spray drying, hot melt extrusion (HME), or co-precipitation are most common. However, these technologies have challenges in terms of the successful stabilization of poor glass former compounds in the amorphous form.

A novel in vivo predictive dissolution testing coupled with a modeling and simulation for hydrogel matrix monolithic extended release oral dosage forms.

The objective of this research was to design a novel in vitro dissolution testing for hydrogel matrix monolithic extended release tablets, in which physiologically relevant conditions of swelling, stress, and erosion for the tablets in the fasted gastrointestinal tract are taken into consideration. Mirabegron extended release tablets (three variations) were used as model formulations in this research. In in vitro dissolution testing, the tablets were allowed to swell in 10 mL of dissolution medium, after which they were stressed under a pressure of ca.

PBPK modeling coupled with biorelevant dissolution to forecast the oral performance of amorphous solid dispersion formulations.

The aim of this research was to develop an in silico modeling and simulation approach to predict the oral performance of a poorly soluble drug candidate, T2CP, formulated as an amorphous solid dispersion and an amorphous powder. The dissolution and precipitation profiles of T2CP of the two amorphous formulations were evaluated in biorelevant media using USP 2 paddle apparatus. Three equations, the Noyes-Whitney equation for dissolution and separate equations describing nucleation and crystal growth, were fitted simultaneously to the in vitro profiles to estimate the dissolution and precipitation parameters for each formulation.

The Discriminatory Power of the BCS-Based Biowaiver: A Retrospective With Focus on Essential Medicines.

This article summarizes historic developments, recent expert opinions, and (currently) unresolved challenges concerning the Biopharmaceutics Classification System (BCS)-based Biowaiver. An overview of approval statistics and application potential, case examples addressing the discriminatory power of the procedure, as well as an outlook on possible refinements in the future are provided and critically discussed. Over the last decade, regulatory guidance documents have been harmonized, for example, following scientific consent on allowing biowaivers for BCS class III drugs, making over 50% of orally administered drugs on the World Health Organization Essential Medicines List eligible for an abbreviated approval.

Predicting the Changes in Oral Absorption of Weak Base Drugs Under Elevated Gastric pH Using an In Vitro-In Silico-In Vivo Approach: Case Examples-Dipyridamole, Prasugrel, and Nelfinavir.

The aim of the current research was to develop an in silico oral absorption model coupled with an in vitro dissolution/precipitation testing to predict gastric pH-dependent drug-drug interactions for weakly basic drugs. The effects of elevated gastric pH on the plasma profiles of dipyridamole, prasugrel, and nelfinavir were simulated and compared with pharmacokinetic data reported in humans with or without use of proton pump inhibitors or histamine H receptor antagonists. The in vitro dissolution and precipitation data for the weakly basic drugs in biorelevant media were obtained using paddle apparatus.

Effects of medicines used to treat gastrointestinal diseases on the pharmacokinetics of coadministered drugs: a PEARRL Review.

Objectives: Drugs used to treat gastrointestinal diseases (GI drugs) are widely used either as prescription or over-the-counter (OTC) medications and belong to both the 10 most prescribed and 10 most sold OTC medications worldwide. The objective of this review article is to discuss the most frequent interactions between GI and other drugs, including identification of the mechanisms behind these interactions, where possible.

Key Findings: Current clinical practice shows that in many cases, these drugs are administered concomitantly with other drug products.

In vitro methods to assess drug precipitation in the fasted small intestine - a PEARRL review.

Objectives: Drug precipitation in vivo poses a significant challenge for the pharmaceutical industry. During the drug development process, the impact of drug supersaturation or precipitation on the in vivo behaviour of drug products is evaluated with in vitro techniques. This review focuses on the small and full scale in vitro methods to assess drug precipitation in the fasted small intestine.

Past, Present, and Future of Bioequivalence: Improving Assessment and Extrapolation of Therapeutic Equivalence for Oral Drug Products.

The growth in the utilization of systems thinking principles has created a paradigm shift in the regulatory sciences and drug product development. Instead of relying extensively on end product testing and one-size-fits-all regulatory criteria, this new paradigm has focused on building quality into the product by design and fostering the development of product-specific, clinically relevant specifications. In this context, this commentary describes the evolution of bioequivalence regulations up to the current day and discusses the potential of applying a Bayesian-like approach, considering all relevant prior knowledge, to guide regulatory bioequivalence decisions in a patient-centric environment.

Approaches to increase mechanistic understanding and aid in the selection of precipitation inhibitors for supersaturating formulations - a PEARRL review.

Objectives: Supersaturating formulations hold great promise for delivery of poorly soluble active pharmaceutical ingredients (APIs). To profit from supersaturating formulations, precipitation is hindered with precipitation inhibitors (PIs), maintaining drug concentrations for as long as possible. This review provides a brief overview of supersaturation and precipitation, focusing on precipitation inhibition.

Biowaiver Monographs for Immediate Release Solid Oral Dosage Forms: Proguanil Hydrochloride.

Literature data relevant to the decision to waive in vivo bioequivalence testing for the approval of generic immediate release solid oral dosage forms of proguanil hydrochloride are reviewed. To elucidate the Biopharmaceutics Classification System (BCS) classification, experimental solubility and dissolution studies were also carried out. The antimalarial proguanil hydrochloride, effective via the parent compound proguanil and the metabolite cycloguanil, is not considered to be a narrow therapeutic index drug.

Solubility Determination of Active Pharmaceutical Ingredients Which Have Been Recently Added to the List of Essential Medicines in the Context of the Biopharmaceutics Classification System-Biowaiver.

Since the publication of Lindenberg et al., which classified orally administered active pharmaceutical ingredients (APIs) on the 2004 Essential Medicines List (EML) of the World Health Organization according to the Biopharmaceutics Classification System (BCS), various APIs have been added to the EML. In this work, BCS classifications for 16 of the orally administered APIs which were added to the EML after 2004 were determined.

Biowaiver Monographs for Immediate-Release Solid Oral Dosage Forms: Folic Acid.

This work presents a review of literature and experimental data relevant to the possibility of waiving pharmacokinetic bioequivalence studies in human volunteers for approval of immediate-release solid oral pharmaceutical forms containing folic acid as the single active pharmaceutical ingredient. For dosage forms containing 5 mg folic acid, the highest dose strength on the World Health Organization Essential Medicines List, the dose/solubility ratio calculated from solubility studies was higher than 250 mL, corresponding to a classification as "not highly soluble." Small, physiological doses of folic acid (≤320 μg) seem to be absorbed completely via active transport, but permeability data for higher doses of 1-5 mg are inconclusive.

Mesoporous silica-based dosage forms improve bioavailability of poorly soluble drugs in pigs: case example fenofibrate.

Objectives: Mesoporous silicas (SLC) have demonstrated considerable potential to improve bioavailability of poorly soluble drugs by facilitating rapid dissolution and generating supersaturation. The addition of certain polymers can further enhance the dissolution of these formulations by preventing drug precipitation. This study uses fenofibrate as a model drug to investigate the performance of an SLC-based formulation, delivered with hydroxypropyl methylcellulose acetate succinate (HPMCAS) as a precipitation inhibitor, in pigs.

Forecasting gastrointestinal precipitation and oral pharmacokinetics of dantrolene in dogs using an in vitro precipitation testing coupled with in silico modeling and simulation.

The aim of the current research was to determine the precipitation kinetics of dantrolene sodium using canine biorelevant in vitro testing and to model the precipitation kinetics by appropriately coupling the data with an in silico tool adapted for dogs. The precipitation profiles of dantrolene sodium solutions were obtained with the in vitro paddle apparatus at a revolution rate of 50rpm. The in silico prediction tool was designed using STELLA software and the predicted plasma concentration profiles of dantrolene using the in vitro precipitation data were compared with the observed in vivo pharmacokinetics in beagle dogs.

Biowaiver Monographs for Immediate-Release Solid Oral Dosage Forms: Enalapril.

Literature data relevant to the decision to allow a waiver of in vivo bioequivalence testing for the marketing authorization of immediate-release, solid oral dosage forms containing enalapril maleate are reviewed. Enalapril, a prodrug, is hydrolyzed by carboxylesterases to the active angiotensin-converting enzyme inhibitor enalaprilat. Enalapril as the maleate salt is shown to be highly soluble, but only 60%-70% of an orally administered dose of enalapril is absorbed from the gastrointestinal tract into the enterocytes.

Mechanistic investigation of the negative food effect of modified release zolpidem.

Aims: When administered orally as either an immediate or modified release dosage form, zolpidem demonstrates a negative food effect, i.e. decrease in C and AUC.

Assessment of Bioequivalence of Weak Base Formulations Under Various Dosing Conditions Using Physiologically Based Pharmacokinetic Simulations in Virtual Populations. Case Examples: Ketoconazole and Posaconazole.

Postabsorptive factors which can affect systemic drug exposure are assumed to be dependent on the active pharmaceutical ingredient (API), and thus independent of formulation. In contrast, preabsorptive factors, for example, hypochlorhydria, might affect systemic exposure in both an API and a formulation-dependent way. The aim of this study was to evaluate whether the oral absorption of 2 poorly soluble, weakly basic APIs, ketoconazole (KETO) and posaconazole (POSA), would be equally sensitive to changes in dissolution rate under the following dosing conditions-coadministration with water, with food, with carbonated drinks, and in drug-induced hypochlorhydria.

Bridging the Gap Between In Vitro Dissolution and the Time Course of Ibuprofen-Mediating Pain Relief.

In vitro-in vivo extrapolation techniques combined with physiologically based pharmacokinetic models represent a feasible approach to establishing links between critical quality attributes and the time course of drug concentrations in vivo. By further integrating the results with pharmacodynamic (PD) models, scientists can also explore the time course of drug effect. The aim of this study was to assess whether differences in dissolution rates would affect the onset, magnitude, and duration of the time course of ibuprofen-mediating pain relief.

Is it possible to achieve bio-equivalence between an oral solid immediate-release and an analogue enteric-coated formulation?

Objectives: While bioequivalence between enteric-coated and immediate-release formulations can be achieved in terms of AUC, gastric emptying of enteric-coated dosage forms is a stochastic event, usually leading to lower Cmax values than those observed with the corresponding immediate release. This article examines challenges of developing enteric-coated dosage forms which are bioequivalent to the corresponding immediate-release formulations in terms of both AUC and Cmax using rasagiline as a model compound.

Methods: In vitro drug release profiles of enteric-coated formulations were obtained and compared to those of the immediate-release formulation by dissolution testing.

Dissolution Methods to Increasing Discriminatory Power of In Vitro Dissolution Testing for Ibuprofen Free Acid and Its Salts.

The predictive capacity of in vitro dissolution tests using the Biopharmaceutics Classification System (BCS)-based experimental setup to anticipate in vivo bioequivalence outcomes for BCS class 2 weak acids has been questioned. In this work, the effect of buffer concentration media was investigated as a possible approach to ensuring the discriminative capacity of the in vitro dissolution methods. The case example used to test this approach was ibuprofen, formulated as either the free acid or in various salt forms.