Bad Homburg vor der Höhe, Germany
Bad Homburg vor der Höhe, Germany

Time filter

Source Type

Guillot A.,PHAST GmbH | Guillot A.,Helmholtz Center for Infection Research | Guillot A.,PHAST Development GmbH and Co. KG | Couffin A.-C.,University Grenoble Alpes | And 8 more authors.
Pharmaceutical Research | Year: 2015

Purpose: Contrary to physical characterization techniques for nanopharmaceuticals (shape, size and zeta-potential), the techniques to quantify the free and the entrapped drug remain very few and difficult to transpose in routine analytical laboratories. The application of Solid Phase Extraction (SPE) technique was investigated to overcome this challenge. Methods: The separation of free and entrapped drug by SPE was quantitatively validated by High Performance Liquid Chromatography. The developed protocol was implemented to characterize cyclosporine A-loaded 120 nm-sized lipid nanoparticles (LNPs, Lipidot®) dispersed in aqueous buffer. The colloidal stability was assessed by Dynamic Light Scattering (DLS). Results: Validation experiments demonstrated suitable linearity, repeatability, accuracy and specificity to quantify residual free, entrapped and total drug. For the investigated LNPs, the method revealed a very limited shelflife of the formulation when stored in an aqueous buffer at 5°C and even more at elevated temperature. Nevertheless, the DLS measurements confirmed the stability of nanoparticles during SPE in a suitable concentration range. Conclusions: SPE, when successfully validated, represents a valuable tool for drug development and quality control purposes of lipid-based nanopharmaceuticals in an industrial environment. © 2015 Springer Science+Business Media New York.


Gajendran J.,PHAST GmbH | Gajendran J.,Johannes Gutenberg University Mainz | Kramer J.,PHAST GmbH | Shah V.P.,International Pharmaceutical Federation | And 7 more authors.
Journal of Pharmaceutical Sciences | Year: 2015

Literature data relevant to the biopharmaceutical properties of the active pharmaceutical ingredient (API) nifedipine are reviewed to evaluate whether a waiver of in vivo bioequivalence (BE) testing of immediate-release (IR) dosage forms formulated as tablets and soft gelatin capsules is warranted. Nifedipine's solubility and permeability, its therapeutic use and index, pharmacokinetics, food drug interactions, and any reported BE/bioavailability problems were all taken into consideration. Solubility and BA data indicate conclusively that nifedipine is a class II substance of biopharmaceutics classification system (BCS) and that the formulation of drug product plays a key role on the dissolution characteristics of the API. Therefore, a BCS biowaiver-based approval of nifedipine containing IR oral dosage forms cannot be recommended for reformulated/new multisource drug products or for major scale-up and postapproval changes to the existing drug products. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 104:3289-3298.


Guillot A.,PHAST GmbH | Guillot A.,Helmholtz Center for Infection Research | Guillot A.,PHAST Development GmbH & Co. KG | Couffin A.-C.,University Grenoble Alpes | And 8 more authors.
Pharmaceutical Research | Year: 2015

Purpose: Contrary to physical characterization techniques for nanopharmaceuticals (shape, size and zeta-potential), the techniques to quantify the free and the entrapped drug remain very few and difficult to transpose in routine analytical laboratories. The application of Solid Phase Extraction (SPE) technique was investigated to overcome this challenge. Methods: The separation of free and entrapped drug by SPE was quantitatively validated by High Performance Liquid Chromatography. The developed protocol was implemented to characterize cyclosporine A-loaded 120 nm-sized lipid nanoparticles (LNPs, Lipidot®) dispersed in aqueous buffer. The colloidal stability was assessed by Dynamic Light Scattering (DLS). Results: Validation experiments demonstrated suitable linearity, repeatability, accuracy and specificity to quantify residual free, entrapped and total drug. For the investigated LNPs, the method revealed a very limited shelflife of the formulation when stored in an aqueous buffer at 5°C and even more at elevated temperature. Nevertheless, the DLS measurements confirmed the stability of nanoparticles during SPE in a suitable concentration range. Conclusions: SPE, when successfully validated, represents a valuable tool for drug development and quality control purposes of lipid-based nanopharmaceuticals in an industrial environment. © 2015 Springer Science+Business Media New York


Reischmann P.,Kaiserslautern University of Applied Sciences | Fiebeck J.,Kaiserslautern University of Applied Sciences | Von Der Weiden N.,PHAST GmbH | Muller O.,Kaiserslautern University of Applied Sciences
International Journal of Cell Biology | Year: 2015

The Wnt signaling pathway has been associated with many essential cell processes. This study aims to examine the effects of Wnt signaling on proliferation of cultured HEK293T cells. Cells were incubated with Wnt3a, and the activation of the Wnt pathway was followed by analysis of the level of the β-catenin protein and of the expression levels of the target genes MYC and CCND1. The level of β-catenin protein increased up to fourfold. While the mRNA levels of c-Myc and cyclin D1 increased slightly, the protein levels increased up to a factor of 1.5. Remarkably, MTT and BrdU assays showed different results when measuring the proliferation rate of Wnt3a stimulated HEK293T cells. In the BrdU assays an increase of the proliferation rate could be detected, which correlated to the applied Wnt3a concentration. Oppositely, this correlation could not be shown in the MTT assays. The MTT results, which are based on the mitochondrial activity, were confirmed by analysis of the succinate dehydrogenase complex by immunofluorescence and by western blotting. Taken together, our study shows that Wnt3a activates proliferation of HEK293 cells. These effects can be detected by measuring DNA synthesis rather than by measuring changes of mitochondrial activity. © 2015 Patricia Reischmann et al.


PubMed | PHAST GmbH and Kaiserslautern University of Applied Sciences
Type: | Journal: International journal of cell biology | Year: 2016

The Wnt signaling pathway has been associated with many essential cell processes. This study aims to examine the effects of Wnt signaling on proliferation of cultured HEK293T cells. Cells were incubated with Wnt3a, and the activation of the Wnt pathway was followed by analysis of the level of the -catenin protein and of the expression levels of the target genes MYC and CCND1. The level of -catenin protein increased up to fourfold. While the mRNA levels of c-Myc and cyclin D1 increased slightly, the protein levels increased up to a factor of 1.5. Remarkably, MTT and BrdU assays showed different results when measuring the proliferation rate of Wnt3a stimulated HEK293T cells. In the BrdU assays an increase of the proliferation rate could be detected, which correlated to the applied Wnt3a concentration. Oppositely, this correlation could not be shown in the MTT assays. The MTT results, which are based on the mitochondrial activity, were confirmed by analysis of the succinate dehydrogenase complex by immunofluorescence and by western blotting. Taken together, our study shows that Wnt3a activates proliferation of HEK293 cells. These effects can be detected by measuring DNA synthesis rather than by measuring changes of mitochondrial activity.


Ermer J.,Sanofi S.A. | Limberger M.,Phast GmbH | Lis K.,Phast GmbH | Watzig H.,TU Braunschweig
Journal of Pharmaceutical and Biomedical Analysis | Year: 2013

Analytical method transfers are certainly among the most discussed topics in the GMP regulated sector. However, they are surprisingly little regulated in detail. General information is provided by USP, WHO, and ISPE in particular. Most recently, the EU emphasized the importance of analytical transfer by including it in their draft of the revised GMP Guideline. In this article, an overview and comparison of these guidelines is provided.The key to success for method transfers is the excellent communication between sending and receiving unit. In order to facilitate this communication, procedures, flow charts and checklists for responsibilities, success factors, transfer categories, the transfer plan and report, strategies in case of failed transfers, tables with acceptance limits are provided here, together with a comprehensive glossary. Potential pitfalls are described such that they can be avoided.In order to assure an efficient and sustainable transfer of analytical procedures, a practically relevant and scientifically sound evaluation with corresponding acceptance criteria is crucial. Various strategies and statistical tools such as significance tests, absolute acceptance criteria, and equivalence tests are thoroughly descibed and compared in detail giving examples. Significance tests should be avoided. The success criterion is not statistical significance, but rather analytical relevance. Depending on a risk assessment of the analytical procedure in question, statistical equivalence tests are recommended, because they include both, a practically relevant acceptance limit and a direct control of the statistical risks. However, for lower risk procedures, a simple comparison of the transfer performance parameters to absolute limits is also regarded as sufficient. © 2013 Elsevier B.V.


Gajendran J.,Johannes Gutenberg University Mainz | Gajendran J.,PHAST GmbH | Kraemer J.,PHAST GmbH | Langguth P.,Johannes Gutenberg University Mainz
Biopharmaceutics and Drug Disposition | Year: 2012

Understanding the performance of a drug product in vivo plays a key role in the development of meaningful in vitro drug release methodology. In case of functional chewing gums, the mode and the mechanism of release and the site of application differ significantly from other conventional solid oral dosage forms and require a special consideration to extract meaningful information from clinical studies. In the current study, suitable drug release methodology was developed to predict the in vivo performance of an investigated chewing gum product. Different parameters of the drug release testing apparatus described in the Ph. Eur. and Pharmeuropa were evaluated. Drug release data indicate that the parameters, chewing distance, chewing frequency and twisting motion, affect the drug release. Higher drug release was observed when the frequency was changed from 40 chews/min to 60 chews/min for apparatus A and B, as was the case for the twisting motion when changed from 20° to 40° for apparatus B. As far as the chewing distance is concerned, the release rate was in the following order; apparatus A: 0.3 mm > 0.5 mm > 0.7 mm; apparatus B: 1.4 mm > 1.6 mm > 1.8 mm. A suitable apparatus set-up for in vitro release testing was identified. The method will be useful for the establishment of in vitro in vivo correlations (IVIVC) for medicated chewing gums. Interchangeability of the apparatus for a product is not generally recommended without prior knowledge of the performance of the product, as the construction and principle of operation for the apparatus differ considerably. Copyright © 2012 John Wiley & Sons, Ltd. Copyright © 2012 John Wiley & Sons, Ltd.


PubMed | PHAST GmbH
Type: Journal Article | Journal: The Journal of pharmacy and pharmacology | Year: 2012

For industrially manufactured pharmaceutical dosage forms, product quality tests and performance tests are required to ascertain the quality of the final product. Current compendial requirements specify a disintegration and/or a dissolution test to check the quality of oral solid dosage forms. These requirements led to a number of compendial monographs for individual products and, at times, the results obtained may not be reflective of the dosage form performance. Although a general product performance test is desirable for orally disintegrating tablets (ODTs), the complexity of the release controlling mechanisms and short time-frame of release make such tests difficult to establish. For conventional oral solid dosage forms (COSDFs), disintegration is often considered to be the prerequisite for subsequent dissolution. Hence, disintegration testing is usually insufficient to judge product performance of COSDFs. Given the very fast disintegration of ODTs, the relationship between disintegration and dissolution is worthy of closer scrutiny. This article reviews the current status of dissolution testing of ODTs to establish the product quality standards. Based on experimental results, it appears that it may be feasible to rely on the dissolution test without a need for disintegration studies for selected ODTs on the market.

Loading PHAST GmbH collaborators
Loading PHAST GmbH collaborators