In Vitro-in Vivo Correlation Model Research Articles

A convolution-based in vitro-in vivo correlation model for methylphenidate hydrochloride delayed-release and extended-release capsule.

Delayed-release and extended-release methylphenidate hydrochloride (JORNAY PM®) is a novel capsule formulation of methylphenidate hydrochloride, used to treat attention deficit hyperactivity disorder in patients 6 years and older. In this paper, we develop a Level A invitro-in vivo correlation (IVIVC) model for extended-release methylphenidate hydrochloride to support post-approval manufacturing changes by evaluating a point-to-point correlation between the fraction of drug dissolved invitro and the fraction of drug absorbed invivo. Dissolution data from an invitro study of three different release formulations: fast, medium, and slow, and pharmacokinetic data from two invivo studies were used to develop an IVIVC model using a convolution-based approach. The time-course of the drug concentration resulting from an arbitrary dose was considered as a function of the invivo drug absorption and the disposition and elimination processes defined by the unit impulse response function using the convolution integral. An IVIVC was incorporated in the model due to the temporal difference seen in the scatterplots of the estimated fraction of drug absorbed invivo and the fraction of drug dissolved invitro and Levy plots. Finally, the IVIVC model was subjected to evaluation of internal predictability. This IVIVC model can be used to predict invivo profiles for different invitro profiles of extended-release methylphenidate hydrochloride.

Computational prediction of pharmacokinetic parameters as an in vitro approach for assessing paracetamol tablets for IVIVC; a strategy in COVID-19 disruptive times.

In vitro-in vivo correlation (IVIVC) is a desirable attribute for any drug dissolution test to establish relevance and confidence in evaluating the quality and safety of products. The pharmacokinetic parameters of paracetamol have been studied extensively but information about the IVIVC is scanty and mostly controversial; this justifies its choice as a model drug for this study. This work is aimed to evaluate and compare the IVIVC dissolution profile of different brands of paracetamol tablets using authentic pharmacokinetic parameters such as; maximum observed dug concentration (Cmax), time to reach Cmax (Tmax) and Area under Curve concentration-time curve (AUC) obtained from literature. In vitro release data were obtained for each brand (n=12) using the USP II apparatus at 50 rpm in 900 ml phosphate buffer of pH 5.8, maintained at 37±0.5 °C and the results were mathematically extrapolated to predict in vivo data. The percent predicted error (% PE) for Cmax ranges from 1.70 to 6.52 % across the brands, while those for Tmax and AUC were < 0 % and > 20 % respectively. The observed low prediction error for Cmax and Tmax (<10 %) demonstrated that the paracetamol IVIVC model was valid based on FDA guidelines. While a satisfactory result could not be achieved for AUC, promising results were obtained exploiting the convolution based IVIVC model.

Development of an In Vitro System To Emulate an In Vivo Subcutaneous Environment: Small Molecule Drug Assessment.

A reliable in vitro system can support and guide the development of subcutaneous (SC) drug products. Although several in vitro systems have been developed, they have some limitations, which may hinder them from getting more engaged in SC drug product development. This study sought to develop a novel in vitro system, namely, Emulator of SubCutaneous Absorption and Release (ESCAR), to better emulate the in vivo SC environment and predict the fate of drugs in SC delivery. ESCAR was designed using computer-aided design (CAD) software and fabricated using the three-dimensional (3D) printing technique. ESCAR has a design of two acceptor chambers representing the blood uptake pathway and the lymphatic uptake pathway, respectively, although only the blood uptake pathway was investigated for small molecules in this study. Via conducting a DoE factor screening study using acetaminophen solution, the relationship of the output (drug release from the "SC" chamber to the "blood circulation" chamber) and the input parameters could be modeled using a variety of methods, including polynomial equations, machine learning methods, and Monte Carlo simulation-based methods. The results suggested that the hyaluronic acid (HA) concentration was a critical parameter, whereas the influence of the injection volume and injection position was not substantial. An in vitro-in vivo correlation (IVIVC) study was developed using griseofulvin suspension to explore the feasibility of applying ESCAR in formulation development and bioequivalence studies. The developed LEVEL A IVIVC model demonstrated that the in vivo PK profile could be correlated with the in vitro release profile. Therefore, using this model, for new formulations, only in vitro studies need to be conducted in ESCAR, and in vivo studies might be waived. In conclusion, ESCAR had important implications for research and development and quality control of SC drug products. Future work would be focused on further optimizing ESCAR and expanding its applications via assessing more types of molecules and formulations.

Evaluating the bioequivalence of two pitavastatin calcium formulations based on IVIVC modeling and clinical study.

In vitro-in vivo correlation (IVIVC) allows prediction of the in vivo performance of a pharmaceutical product based on its in vitro drug release profiles and can be used to reduce the number of bioequivalence (BE) studies during product development, and facilitate certain regulatory decisions. Here, we developed an IVIVC model for pitavastatin calcium, a basic Biopharmaceutics Classification System (BCS) II lipid-lowering drug, which was then used to predict the BE outcome of formulations manufactured at two manufacturers. In addition, virtual trials using the IVIVC model using pH4.0 acetate buffer dissolution showed similarity in areas under the curves and maximum plasma concentration (Cmax ) for test and reference tablets under fasting condition. These predicted results were verified in definitive BE study. In conclusion, we demonstrated that for certain BCS II molecules, IVIVC modeling could be used as a priori to predict the BE outcome.

Development of an In Vitro Drug Release Method to Enable In Vitro-In Vivo Correlation of Potassium Chloride Extended-Release Tablets.

An in vitro drug release test was developed to establish a level A in vitro-in vivo correlation (IVIVC) for predicting the in vivo performance of potassium chloride extended-release (ER) matrix tablets. Three ER formulations of potassium chloride with different in vitro release rates were designed using the USP dissolution test, and their urinary pharmacokinetic profiles were evaluated in healthy subjects. Due to the lack of IVIVC with the USP method, experiments were designed to investigate the effects of in vitro test conditions on drug release in order to match in vitro drug release with in vivo behaviors of different formulations. The evaluated in vitro variables included the type of USP apparatus, surfactant, and ionic strength of the dissolution medium. Based on the study findings and data analysis, a discriminatory drug release method was successfully developed that enabled the establishment and validation of a level A IVIVC model of the potassium chloride ER tablet using urinary pharmacokinetic data. This method uses USP apparatus I at 50 rpm in 900 mL of 150 mM NaCl solution containing 40 mM sodium dodecyl sulfate at 37 °C. The current study highlights the value of investigating test conditions in developing a predictive in vitro test method for establishing IVIVC.

Population pharmacokinetics and IVIVC for mesalazine enteric-coated tablets.

Although in-vivo bioequivalence (BE) study serves as a golden standard for establishing interchangeability of oral dosage forms, it remains challenging for products with high inter-subject variability such as mesalazine enteric-coated tablet to fulfil the BE criteria set by regulatory authorities. Mesalazine, as a BCS class IV drug, targets to be delivered to distal ileum or colon with a pH-sensitive polymer coating for the remission of ulcerative colitis. Through population pharmacokinetic (PK) analysis and in-vitro in-vivo correlation (IVIVC) modeling on the dissolution and BE data of a generic enteric-coated product (EM) and its reference Salofalk® 250mg tablet (SM), we for the first time revealed the underlying mechanism of the high inter-subject variability for such delayed-release formulation. It was also noted that the in-vivo start time of absorption (Ts) for EM and SM was positively correlated with their in-vitro lag time (Tlag) under the USP three-stage dissolution condition and reversely correlated with their in-vivo bioavailability. The varied oral bioavailability of mesalazine enteric-coated tablet was mainly due to the varied N-acetyltransferase activities along GI tract. Although such extensive intestinal first-pass metabolism with large individual differences led to a significant variation of mesalazine Cmax (coefficient of variation: 60-63.5%) and AUC0-t (coefficient of variation: 37.5-46.9%), the corresponding variations in the total absorbed mesalazine (mesalazine and its metabolite N-acetyl mesalazine) were significantly reduced by 12 to 45%. Since the BE purpose for mesalazine enteric-coated tablet focused on their comparable safety profiles, total absorbed mesalazine was recommended to be adopted for the development of the IVIVC model and BE evaluation for EM. All in all, our model-based approach has not only successfully identified the key factors that affect the BE of EM to guide its further formulation optimization, but also demonstrated the indispensable role of modeling in the development of generic pharmaceutical product at its early stages.

Novel extended IVIVC combined with DoE to predict pharmacokinetics from formulation compositions

The objective of this study was to develop a novel extended in vitro in vivo correlation (IVIVC) model combined with design of experiment (DoE) that integrates the DoE into IVIVC, which can predict the pharmacokinetics of sustained-release (SR) tablets from their formulation compositions, and vice versa. To develop the extended IVIVC model, ketoprofen was used as a model drug. Nineteen types of ketoprofen SR tablets with different formulation compositions were prepared based on the mixture design and used to derive mathematical relationships between the formulation composition and the in vitro dissolution profiles for DoE. The predictability of the DoE equation was externally validated by using additional seven types of SR formulations with prediction errors (%PE) of less than 11.45%. For the development of IVIVC model, three SR formulations that have fast, medium, and slow drug-releasing rates were selected, and the in vivo pharmacokinetics were assessed in Beagle dogs. The pharmacokinetic properties of ketoprofen SR tablets were described by a population pharmacokinetics (POP-PK) model which incorporated the pH-dependent dissolution of ketoprofen by a time-dependent Hill-type equation. The final POP-PK model could describe the overall in vivo pharmacokinetic profiles and allowed estimation of the in vivo dissolution parameters. The POP-PK model estimated in vivo dissolution parameter, Kdiss, in vivo were then correlated with the in vitro dissolution parameter, Kdiss, in vitro by linear regression (R2 = 0.9989), establishing IVIVC. Finally, the equation derived from DoE was introduced to the IVIVC model to develop the extended IVIVC, which connects the formulation composition, in vitro dissolution, and in vivo pharmacokinetic profiles. The average %PE of the final extended IVIVC model was 4.24% for Cmax and 4.46% and AUC. Finally, the final extended IVIVC was applied to predict the in vivo PK profiles of SR tablets from their formulation compositions as well as to design the optimal formulation to achieve certain target PK profiles. The %PE of the final extended IVIVC model was less than 14.67% for Cmax and 12.41% for AUC, satisfying the FDA criteria of conventional IVIVC. The present extended IVIVC model may provide a useful tool towards rationalized design and development of new SR formulations.

Evaluation of in vitro/in vivo correlations for three fentanyl transdermal delivery systems using in vitro skin permeation testing and human pharmacokinetic studies under the influence of transient heat application

The value of developing an in vitro/in vivo correlation (IVIVC) is substantial in biopharmaceutical drug development because once the model is developed and validated, an in vitro method may be used to efficiently assess and predict drug product performance in vivo. In this study, three bioequivalent, matrix-type, fentanyl transdermal delivery systems (TDS) were evaluated in vitro using an in vitro permeation test (IVPT) and dermatomed human skin, and in vivo in human pharmacokinetic (PK) studies under harmonized study designs to evaluate IVIVC. The study designs included 1 h of transient heat application (42 ± 2°C) at either 11 h or 18 h after TDS application to concurrently investigate the influence of heat on drug bioavailability from TDS and the feasibility of IVPT to predict the effects of heat on TDS in vivo. Level A (point-to-point) and Level C (single point) IVIVCs were evaluated by using PK-based mathematical equations and building IVIVC models between in vitro fraction of drug permeation and in vivo fraction of drug absorption. The study results showed that the three differently formulated fentanyl TDS have comparable (p > 0.05) heat effects both in vitro and in vivo. In addition, the predicted steady-state concentration (Css) from in vitro flux data and the observed Css in vivo showed no significant differences (p > 0.05). However, the effects of heat on enhancement of fentanyl bioavailability observed in vivo were found to be greater compared to those observed in vitro for all three drug products, resulting in a weak prediction of the impact of heat on bioavailability from the in vitro data. The results from the current work suggest that while IVPT can be a useful tool to evaluate the performance of fentanyl TDS in vivo with a relatively good predictability at a normal temperature condition and to compare the effect of heat on drug delivery from differently formulated TDS, additional testing measures would enhance the ability to predict the heat effects in vivo with a lower prediction error.

Characterization, in vitro dissolution, and pharmacokinetics of different batches of efavirenz raw materials

Objective To perform the solid-state characterization and the in vitro-in vivo correlation (IVIVC) of three batches of efavirenz (EFV) active pharmaceutical ingredients. Significance EFV is an effective anti-HIV drug. Due to the poor aqueous solubility, the rate and extent of EFV absorption deeply depend on its dissolution characteristics. Methods Thermal analyses, x-ray diffraction, and particle size distribution were performed. The saturation solubility and dissolution profiles were assessed in 0.5% (w/v) sodium lauryl sulfate (SLS), fasted-state simulated intestinal fluid (FaSSIF), and fed-state simulated intestinal fluid (FeSSIF) using a flow-through cell. Each batch was orally administered to Wistar rats and the pharmacokinetic parameters were correlated with those obtained from in vitro dissolution. Results All batches of EFV consisted polymorph I. EFV-A presented the lowest particle size distribution [d(v,0.5) = 197.8 µm; d(v,0.9) = 444.6 µm] followed by EFV-B [d(v,0.5) = 223.9 µm; d(v,0.9) = 481.1 µm], and EFV-C [d(v,0.5) = 240.8 µm; d(v,0.9) = 497.3 µm]. The saturated solubility in FaSSIF was 36% and 40% of that in FeSSIF and SLS, respectively. EFV-A presented the fastest rate and largest extension of dissolution than EFV-B and C (79.15%, 69.93% and 54.22%, respectively, as well as the highest maximum plasma concentration. Levels B, C, and multiple-C of IVIVC models were achieved. Conclusion The FaSSIF medium discriminated the dissolution profiles of EFV APIs. Small differences in particle size distribution had a significant impact on the biopharmaceutical parameters of EFV, suggesting that strict control of such parameter is an important aspect during API development and drug formulation.

On Absorption Modeling and Food Effect Prediction of Rivaroxaban, a BCS II Drug Orally Administered as an Immediate-Release Tablet.

The present work evaluates the food effect on the absorption of rivaroxaban (Riva), a BCS II drug, from the orally administered commercial immediate-release tablet (Xarelto IR) using physiologically based pharmacokinetic (PBPK) and conventional in vitro–in vivo correlation (IVIVC) models. The bioavailability of Riva upon oral administration of Xarelto IR tablet is reported to exhibit a positive food effect. The PBPK model for Riva was developed and verified using the previously reported in vivo data for oral solution (5 and 10 mg) and Xarelto IR tablet (5 and 10 mg dose strength). Once the PBPK model was established, the in vivo performance of the tablet formulation with the higher dose strength (Xarelto IR tablet 20 mg in fasted and fed state) was predicted using the experimentally obtained data of in vitro permeability, biorelevant solubility and in vitro dynamic dissolution data using United States Pharmacopeia (USP) IV flow-through cell apparatus. In addition, the mathematical IVIVC model was developed using the in vitro dissolution and in vivo profile of 20 mg strength Xarelto IR tablet in fasted condition. Using the developed IVIVC model, the pharmacokinetic (PK) profile of the Xarelto IR tablet in fed condition was predicted and compared with the PK parameters obtained via the PBPK model. A virtual in vivo PK study was designed using a single-dose, 3-treatment cross-over trial in 50 subjects to predict the PK profile of the Xarelto® IR tablet in the fed state. Overall, the results obtained from the IVIVC model were found to be comparable with those from the PBPK model. The outcome from both models pointed to the positive food effect on the in vivo profile of the Riva. The developed models thus can be effectively extended to establish bioequivalence for the marketed and novel complex formulations of Riva such as amorphous solid dispersions.

In Vitro-In Vivo Correlation (IVIVC) Population Modeling for the In Silico Bioequivalence of a Long-Acting Release Formulation of Progesterone.

Health authorities carefully evaluate any change in the batch manufacturing process of a drug before and after regulatory approval. In the absence of an adequate in vitro–in vivo correlation (Level A IVIVC), an in vivo bioequivalence (BE) study is frequently required, increasing the cost and time of drug development. This study focused on developing a Level A IVIVC for progesterone vaginal rings (PVRs), a dosage form designed for the continuous delivery in vivo. The pharmacokinetics (PK) of four batches of rings charged with 125, 375, 750 and 1500 mg of progesterone and characterized by different in vitro release rates were evaluated in two clinical studies. In vivo serum concentrations and in vitro release profiles were used to develop a population IVIVC progesterone ring (P-ring) model through a direct differential-equation-based method and a nonlinear-mixed-effect approach. The in vivo release, , was predicted from the in vitro profile through a nonlinear relationship. was used as the input of a compartmental PK model describing the in vivo serum concentration dynamics of progesterone. The proposed IVIVC P-ring model was able to correctly predict the in vivo concentration–time profiles of progesterone starting from the in vitro PVR release profiles. Its internal and external predictability was carefully evaluated considering the FDA acceptance criteria for IVIVC assessment of extended-release oral drugs. Obtained results justified the use of the in vitro release testing in lieu of clinical studies for the BE assessment of any new PVRs batches. Finally, the possible use of the developed population IVIVC model as a simulator of virtual BE trials was explored through a case study.

A novel combination of Soluplus®/Poloxamer for Meloxicam solid dispersions via hot melt extrusion for rapid onset of action. Part 2: comparative bioavailability and IVIVC

Objective Bioavailability of Meloxicam (MLX) from solid dispersions (SDs), against innovator product Mobic® in humans was conducted. Furthermore, to establish a good in vitro–in vivo correlation (IVIVC); dissolution studies were carried-out in different media. Methods MLX/SDs was prepared using Soluplus/Poloxamer via hot-melt-extrusion (EXT-SD) and fusion melt (FUS-SD) techniques. A single oral dose (15 mg), three periods, crossover study of MLX/SDs and Mobic® in four healthy humans under fed conditions was carried-out. In vitro dissolution was studied in pH 1.2, distilled water (pH 6.4), and biorelevant simulated gastric media in pre- and post-prandial states. Level A IVIVC was carried-out by comparing time-scaled fraction dissolved versus fraction absorbed and calculated using the Wagner-Nelson method. Multiple level C models were developed for C max and AUC0–96 versus % dissolved at different time-points. Internal predictability was evaluated for both IVIVC models. Results MLX rate of absorption (T max) from EXT-SD, FUS-SD, and Mobic® was 1.5, 3.0, and 4.0 h, respectively. Moreover, 1.45- and 1.40-folds increase in AUC0–∞ and C max, was obtained for EXT-SD versus Mobic®, respectively, while FUS-SD gave the lowest extent of drug absorption. EXT-SD provided highest dissolution profiles in all studied media. IVIVC models showed linear-regression (R 2≥0.90) and prediction errors (≤10%) in water and post-prandial simulated gastric media. Conclusion Hot-melt-extrusion technology promises an ideal alternative for enhancing MLX extent of absorption compared to Mobic® with T max value almost equal to the reported intramuscular injection. Predictive IVIVC was established for in vitro dissolution profile and in vivo performance.

In Vitro-In Vivo Correlation for Desvenlafaxine Succinate Monohydrate Extended Release Tablets.

The objective of this study was to develop a dissolution test in order to establish an in vitro-in vivo correlation (IVIVC) model for desvenlafaxine succinate monohydrate (DVSM) extended release (ER) tablets. The in vitro release characteristics of the drug were determined using USP apparatus 1 at 75rpm, with volume of HCl pH1.2, acetate buffer solution (ABS) pH4.5, or phosphate buffer solution (PBS) pH6.8. In vivo plasma concentrations and pharmacokinetic parameters in healthy volunteers were obtained from a bioequivalence study. The similarity factors f1 and f2 were used to compare the dissolution data. The IVIVC model was developed using fraction dissolved and fraction absorbed of the reference product. For predictability, the results showed that the percentage prediction error (%PE) value of Cmax was 7.63%. The observed low prediction error for Cmax demonstrated that the IVIVC model was valid for this parameter.

In vitro - In vivo correlation in the development of oral drug formulation: A screenshot of the last two decades.

In vitro - in vivo correlation (IVIVC) allows prediction of the in vivo performance of a pharmaceutical product based on its in vitro drug release profiles and can be used to optimize formulations, set dissolution limits, reduce the number of bioequivalence studies during product development, and facilitate certain regulatory decisions. This review article aimed to assess papers published in the last two decades regarding the use of the IVIVC in the development of oral formulations, to demonstrate the scenario in this area, as well as to describe the main characteristics of the assessed studies. A systematic search of PubMed and Web of Science databases was conducted to retrieve articles reporting the use of the IVIVC in the oral formulation development in the period from 1998 to 2018. The qualified studies were abstracted regarding drug name, dosage form, BCS class, in vitro and in vivo data, level of IVIVC, number of formulations, presence of the validation and predictability. The discussion was supported by these data, which allowed to address broadly strengths and weaknesses in this area. Moreover, a large database has been described in this article containing different IVIVC models, with different substances, providing support to scientists interested in this area.

Development of a Population Pharmacokinetics-Based in vitro-in vivo Correlation Model for Drugs with Site-Dependent Absorption: the Acyclovir Case Study.

Acyclovir is a Biopharmaceutics Classification System (BCS) class III antiviral agent which is only absorbed in the upper part of the gastrointestinal tract. This study aimed to establish a new in vitro-in vivo correlation (IVIVC) platform based on population pharmacokinetic modeling for drugs with site-dependent absorption using acyclovir as a model drug. Three types of sustained-release (SR; 500mg) acyclovir tablets were prepared by the wet granulation method. The in vitro dissolution profiles of the acyclovir SR tablets and the immediate-release (IR; 200mg) were determined by the paddle method and their in vivo pharmacokinetics were evaluated in Beagle dogs. A population pharmacokinetic model was developed using S-ADAPT. By separating the dissolution and absorption processes, the population pharmacokinetic model adequately described all the in vivo pharmacokinetic data and estimated the in vivo dissolution profiles. The changes of absorption rate over time after oral administration were also successfully estimated. The parameter estimates of the in vitro and in vivo drug releases were correlated by linear regression. Finally, the in vivo pharmacokinetic profiles were well predicted by the developed IVIVC model from the in vitro dissolution data with the prediction errors within 8.26% and 10.06% for the maximum plasma concentration (Cmax) and area under the plasma concentration-time curve (AUC), respectively. The present approach provides a better understanding of the in vivo absorption for drugs that have limited absorption window and may be useful for their new formulation design and development.

Development of Level A In Vitro-Vivo Correlation for Electrosprayed Microspheres Containing Leuprolide: Physicochemical, Pharmacokinetic, and Pharmacodynamic Evaluation.

This study optimized the preparation of electrosprayed microspheres containing leuprolide and developed an in vitro–in vivo correlation (IVIVC) model that enables mutual prediction between in vitro and in vivo dissolution. The pharmacokinetic (PK) and pharmacodynamic (PD) study of leuprolide was carried out in normal rats after subcutaneous administration of electrosprayed microspheres. The parameters of the IVIVC model were estimated by fitting the PK profile of Lucrin depot® to the release compartment of the IVIVC model, thus the in vivo dissolution was predicted from the in vitro dissolution. From this correlation, the PK profile of leuprolide was predicted from the results of in vivo dissolution. The IVIVC model was validated by estimating percent prediction error (%PE) values. Among prepared microspheres, an optimal formulation was selected using the IVIVC model. The maximum plasma concentration and the area under the plasma concentration–time curve from zero to infinity from the predicted PK profile were 4.01 ng/mL and 52.52 h·ng/mL, respectively, and from the observed PK profile were 4.14 ng/mL and 56.95 h·ng/mL, respectively. The percent prediction error values of all parameters did not exceed 15%, thus the IVIVC model satisfies the validation criteria of the Food and Drug Administration (FDA) guidance. The PK/PD evaluation suggests that the efficacy of OL5 is similar to Lucrin depot®, but the formulation was improved by reducing the initial burst release.

A Review on IVIVC in The Development of Oral Drug Formulation: Data Obtained from Past Two Decades

Rapidity in Drug development can be achieved by researchers on finding a mathematical link between bioavailability and dissolution testing which leads to the concept of in vitro -in vivo correlation (IVIVC). This review article aimed to assess papers published in the last two decades regarding the use of the IVIVC in the development of oral formulations. A systematic search was done to retrieve articles reporting the use of the IVIVC in the oral formulation development in the period from 2000 to2020. The qualified studies were abstracted regarding the Biopharmaceutical Classification System (BCS)that explains the suitability of IVIVC, drug name, dosage form number of formulations, presence of the validation and predictability. The discussion was supported by these data, which allowed to address broadly strengths and weaknesses in thisarea. Moreover, a large database has been described in this article containing different IVIVC models, with different substances, providing support to scientists interested in this area.

Development and validation of a Level A in-vitro in-vivo correlation for tofacitinib modified-release tablets using extrudable core system osmotic delivery technology

PurposeTo determine if a validated Level A in-vitro in-vivo correlation (IVIVC) could be achieved with the extrudable core system (ECS) osmotic tablet platform. Tofacitinib is an oral JAK inhibitor for the treatment of rheumatoid arthritis. MethodsFast-, medium-, and slow-release modified-release formulations of 11 mg tofacitinib ECS tablets, and one formulation of 22 mg tofacitinib ECS tablet, were manufactured. In vitro dissolution of the tofacitinib ECS tablets was performed using USP Apparatus 2 (paddles) and in vivo pharmacokinetic (PK) data were obtained from a Phase 1 study in healthy volunteers. A 5 mg immediate-release formulation tablet was included to support deconvolution of the tofacitinib ECS PK tablet data to obtain the in vivo absorption profiles. A linear, piecewise correlation and a simple linear correlation were used to build and validate two IVIVC models. ResultsThe prediction errors (PEs) for the linear, piecewise correlation met the Food and Drug Administration's criteria for establishing a Level A IVIVC, with a maximum absolute individual internal PE of 4.6%, a maximum absolute average internal PE of 3.9%, and a maximum absolute external PE of 8.4% obtained. ConclusionsThis study demonstrates that the tofacitinib ECS osmotic tablet platform can achieve a Level A IVIVC, similar to other osmotic delivery systems.

Novel extended in vitro-in vivo correlation model for the development of extended-release formulations for baclofen: From formulation composition to in vivo pharmacokinetics

In vitro-in vivo correlation (IVIVC), a predictive mathematical model between the in vitro dissolution and the in vivo pharmacokinetics has been utilized for the development of new extended release (ER) formulations. The aim of the present study was to extend the IVIVC approach, which correlates among the formulation composition, the in vitro dissolution, and the plasma drug concentration, to predict plasma drug concentrations from a given composition of the formulation, and vice versa, using baclofen as a model drug. Baclofen ER tablets with different dissolution rates were prepared by varying the composition of hydroxypropyl methylcellulose (HPMC). First, the HPMC compositions and the corresponding in vitro dissolutions parameters were correlated, and then the in vitro dissolution parameters were correlated with the in vivo dissolution parameters extracted from the pharmacokinetic profiles of the baclofen ER formulations via population pharmacokinetic modeling. The final extended IVIVC model linked the composition of the formulation, the in vitro dissolution, and the in vivo plasma concentration profile and was successfully applied for the prediction of in vivo pharmacokinetics from the amount of HPMC in baclofen ER formulations. The present approach holds great promise for designing optimal compositions of ER formulations to present desired plasma concentration profile.

Development of a Clinically Relevant Dissolution Method for Metaxalone Immediate Release Formulations Based on an IVIVC Model.

The aim of the present work was to classify metaxalone according to the Biopharmaceutics Classification System (BCS), to develop a clinically relevant dissolution method that can be used to predict the oral absorption of metaxalone and to establish an in vitro-in vivo correlation (IVIVC). Solubility of the drug was studied in different pH media and permeability studies were performed using a Caco-2 cell model. The in vitro dissolution and in vivo disposition of metaxalone from 3 different immediate release (IR) tablet formulations were investigated using USP 2 apparatus and a single dose, four-way, crossover bioequivalence study in healthy humans along with an oral solution of the drug, respectively. An IVIVC was established by using a direct, differential based method. Metaxalone has been confirmed as a Class II drug according to BCS. Bioavailability studies performed in humans demonstrated that dissolution was the rate limiting step for bioavailability of the drug and one of the test products had significantly improved bioavailability compared to the marketed product Skelaxin®. An IVIVC model was developed that demonstrated an acceptable internal predictability. The IVIVC demonstrated that formulation factors play a significant role in dissolution and absorption of metaxalone. A pH 4.5 dissolution medium containing 0.5% NaCl with 0.2% SLS (USP apparatus 2 at 50 rpm) is clinically relevant to predict bioavailability of the drug and is superior to the USP method in terms of the Quality by Design (QbD) concept.