Pharmeuropa bio & scientific notes最新文献

In trying to estimate the separation efficiency of Capillary Electrophoresis (CE) methods, the resolution (RS), the number of theoretical plates (N) and the peak-to-valley ratio (p/v) are often used assessment criteria. This study demonstrates that these criteria are not as suitable to describe the separation efficiency in case of Capillary Zone Electrophoresis (CZE) methods as they are for Liquid Chromatography (LC) methods. The investigations were performed by means of a validated CZE method for the evaluation of tetracyclines and their related substances. Four impurities of tetracycline hydrochloride are described in the European Pharmacopoeia. Three were found in the sample used for our investigations, i.e. epi-tetracycline formed by keto-enol-tautomerism, anhydrotetracyclin and epi-anhydrotetracyline. It could be shown that higher values of these assessment criteria like RS do not necessarily represent better separation. Thus, a discussion on the usefulness of separation selectivity and efficiency as assessment criteria for capillary electrophoresis as well as on the introduction of additional parameters is needed.

A joint collaborative study was organised by the European Directorate for the Quality of Medicines & HealthCare (EDQM) and the World Health Organization (WHO)/National Institute for Biological Standards and Control (NIBSC) to establish replacement batches for the European Pharmacopoeia (Ph. Eur.) Tetanus Vaccine (adsorbed) Biological Reference Preparation (BRP) batch 2 and for the WHO 3rd International Standard (IS) for Tetanus toxoid (adsorbed). Two freeze-dried stabilised tetanus vaccine (adsorbed) candidate preparations (Preparation A, 08/218 and Preparation B, 08/102) were calibrated against the current 3rd IS/BRP batch 2 (Preparation C) using challenge methods in guinea pigs and mice as described in the Ph. Eur. general chapter 2.7.8. Assay of tetanus vaccine (adsorbed). They were also assayed by serology methods. The WHO 2nd IS for Tetanus toxoid adsorbed (TEXA-2) was additionally included in the sample panel as Preparation D. Thirty-four laboratories (regulatory organisations and manufacturers) from 22 countries participated in the collaborative study. The majority of participants performed 2 independent challenge tests. Nine laboratories performed challenge assays in guinea pigs and 30 laboratories performed challenge assays in mice. Eight laboratories performed serology in guinea pigs and 1 laboratory performed serology in mice. For Preparation A, the geometric mean (GM) potency estimate (with 95 % confidence interval (CI)) in guinea pigs for all laboratories that provided valid results (n = 6) was 488.5 (354.2-673.6) IU/ampoule. For valid mouse assays (n = 25) the GM potency (with 95 % CI) was 259.8 (223.5-302.0) IU/ampoule. The inter-laboratory geometric coefficient of variation (GCV) was 36 % for guinea pig assays and 45 % for mouse assays. This compared favourably with the calibration of the 3rd IS/BRP batch 2 where the inter-laboratory GCV was 36 % and 42 % in guinea pigs and mice, respectively. For Preparation B, the GM potency estimate (with 95 % CI) in guinea pigs for all laboratories that provided valid results (n = 6) was 107.9 (64.1-181.7) IU/ampoule. For valid mouse assays (n = 24) the GM potency (with 95 % CI) was 147.9 (126.3-173.1) IU/ampoule. The inter-laboratory GCV was 64.3 % for guinea pig assays and 45.2 % for mouse assays. From the collaborative study, Preparation A appeared more suitable to be the replacement Ph. Eur. BRP as it is similar to the Tetanus vaccine (adsorbed) BRP batch 2, except for nature of the stabiliser. Preparation A was confirmed to have higher potency, readily detectable tetanus toxoid, and confirmed satisfactory stability and performance in challenge assays. Preparation A was adopted in January 2011 by the Ph. Eur. Commission as the Tetanus vaccine (adsorbed) BRP batch 3, with assigned potencies of 490 IU/ampoule in the guinea pig challenge assay and of 260 IU/ampoule in the mouse challenge assay. The same Preparation A was adopted in October 2010 as the WHO 4th IS for Tetanus toxoid (adso

To guarantee the safety of medicinal products as regards infectious agents, numerous national guidelines and recommendations have in recent years been included in the pharmacopoeia general monographs and have influenced the content of the substance monographs. Although the stipulations of the European Pharmacopoeia set out objectives, there is still a certain scope in how the requirements are implemented. This is reflected in the very different responses in Europe to the problems of safety from infection. Different traditions in the use of homoeopathic and anthroposophic therapy and varying levels of expertise among the regulatory authorities within the European Union have resulted in varying standard of assessment. The aim of this publication is to present a standard form of assessment for medicinal products in these therapeutic systems. Demonstrated hereunder is an approach that can be adopted to ensure that the high safety standard required is met for homoeopathic and anthroposophic medicinal products.

A collaborative study was run by the Biological Standardisation Programme (BSP) under the aegis of the European Directorate for the Quality of Medicines & HealthCare (EDQM, Council of Europe) and the European Union (EU) Commission, to address the issue of the poor standardisation of serological assays used for the evaluation of seasonal influenza vaccines in Europe. The Phase 1 of the study focused on the compliance to Committee for Human Medicinal Products (CHMP) criteria by 6 manufacturers and 5 public laboratories. It confirmed the poor inter-laboratory correlation of haemagglutination inhibition (HI) test results. Phase 2 consisted in a reproducibility study examining the impact of extended method standardisation and the use of reference sera on inter-laboratory variation. Six manufacturers and 5 public laboratories contributed HI results, while the 5 public laboratories also performed single radial haemolysis (SRH) tests on the same sample panels. Results showed that method standardisation failed to significantly improve the inter-laboratory variation. Correction for pre-vaccination titres (Beyer correction) was found to have limited effect to improve the bias constituted by the Protection Rate (PR) criterion. The reasons underlying the difficulty in standardisation of HI and SRH tests are discussed and improved approaches for the compliance testing to CHMP criteria are suggested.

The Quality of Medicines & HealthCare (EDQM, Council of Europe) and the European Union (EU) Commission to evaluate the reproducibility of clinical serology results for seasonal influenza vaccines and to assess the impact of technical differences between laboratories on the compliance with the Committee for Human Medicinal Products (CHMP) criteria set by the European Medicines Agency (EMA). The study was run in 2 phases. The present article reports the 1st phase of the study, which aimed at evaluating the variability of the results obtained by 11 laboratories (5 national control laboratories and 6 influenza vaccine manufacturers) using their routine haemagglutination inhibition (HI) assay to test a common panel of clinical trial sera. The results confirmed the limited inter-laboratory reproducibility of the HI testing of influenza vaccine clinical trial samples. In some cases a good agreement was found between laboratories, while a systematic bias or a random scatter of results was observed in other cases. Analysis of estimated systematic bias confirmed that differences between laboratories can be significant (up to 16-fold) in some cases. Correction for this bias resulted in limited improvement. Differences between laboratories were found to result in discrepant decisions on marketing acceptance of vaccines or to decisions based on compliance to different criteria. The study showed that the seroconversion (SC) and mean fold increase (MFI) criteria are more robust against systematic over- or under-estimation of titres whereas the protection rate (PR) is very sensitive to this effect. The fundamental issues with the PR criteria are discussed.

An international collaborative study was organised by the European Directorate for the Quality of Medicines & HealthCare (EDQM) to establish the WHO second International Standard (IS) for gramicidin as the stocks of the 1st IS, established in 1964, were close to depletion. The candidate material did not show any sign of potency loss when kept at elevated temperatures of + 4 °C, + 20 °C, + 37 °C and + 45 °C for 3 months. Six laboratories from 5 countries as well as the EDQM laboratory participated in the collaborative study. Potencies of the candidate material were estimated by microbiological assays with sensitive micro-organisms. To ensure continuity between consecutive batches, the 1st IS for gramicidin was used as standard. Based on the results of the study, the 2nd IS for gramicidin was adopted at the meeting of the WHO Expert Committee on Biological Standardization (ECBS) in 2008 with an assigned potency of 1070 International Units per mg (IU/mg). The 2nd IS for gramicidin is available from the EDQM.

The European Pharmacopoeia Biological Reference Preparation (Ph. Eur. BRP) Batch 4 was established as an international common working standard for potency determination of human coagulation factor VIII (FVIII) preparations to replace the dwindling stocks of the BRP Batch 3, the current European standard. Similarly, stocks of the current World Health Organisation 7th International Standard (WHO 7th IS) were also running low. Therefore a project was jointly organised by the European Directorate for the Quality of Medicines & HealthCare (EDQM, Council of Europe) and the National Institute for Biological Standards and Control (NIBSC, UK) in order to replace both standards concomitantly. The potency of the BRP Batch 4 was assigned during an international collaborative study involving 38 laboratories with reference to the WHO 7th IS and the BRP Batch 3. Four candidate materials, 2 plasma-derived (samples A and C) and 2 recombinant (samples B and D) have been evaluated, sample C being the specific candidate for the replacement of the BRP Batch 3. Participants were instructed to perform 8 independent assays following their own routine validated methods, by either the one-stage clotting assay or the chromogenic assay, or both. Laboratories returned 22 data sets for the clotting assay and 30 data sets for the chromogenic assay. This publication reports the results obtained with both assays but only the results of the chromogenic assay are highlighted in the conclusions, as it is the assay prescribed by the European Pharmacopoeia. Data were analysed separately for both assays. The consensus potency value was calculated as the unweighted geometric mean of the unweighted geometric means of each individual laboratory. For sample C, there was a significant difference in potency estimate between the chromogenic and the clotting assay. It was therefore not possible to reconcile both results. The chromogenic potencies however were in very good agreement being 10.4 IU/ampoule (n = 30), when assessed against both standards. The inter-laboratory geometric coefficient of variation (GCV) was 4.8 % and 7.1 % against the WHO 7th IS and the BRP Batch 3 respectively. The Ph. Eur. BRP Batch 4 is a freeze-dried, plasma-derived concentrate. The material was filled in approximately 20,000 ampoules and lyophilised. The final residual water content is 0.33 %. Based on accelerated degradation studies, the stability of the material is suitable for a reference preparation. The candidate Ph. Eur. BRP Batch 4 was adopted at the 136th session of the European Pharmacopoeia Commission in March 2010. The standard will be available from the EDQM with the catalogue number H0920000 upon exhaustion of the current batch.

A collaborative study was run by the European Directorate for the Quality of Medicines & HealthCare (EDQM) in the context of the Biological Standardisation Programme (BSP), under the aegis of the Council of Europe and the European Commission, to establish replacement batches for the dwindling stocks of the Heparin low-molecular-mass for assay European Pharmacopoeia Biological Reference Preparation (BRP). The replacement batches of BRP are intended to be used in the assays for anti-Xa and anti-IIa activities, as described in the European Pharmacopoeia (Ph. Eur.) monograph Heparins, low-molecular-mass (0828). Three freeze-dried candidate batches were calibrated against the current International Standard (IS) for Heparin, lowmolecular- weight (2nd IS, 01/608). For the purpose of the continuity check between subsequent BRP batches, the current Heparin low-molecular-mass for assay BRP (batch 5) was also included in the test panel. Thirteen official medicines control and manufacturers laboratories from European and non-European countries contributed data. A central statistical analysis of the datasets was performed at the EDQM. On the basis of the results, the 3 candidate materials were assigned a potency of 104 IU/vial for the anti-Xa activity and 31 IU/vial for the anti-IIa activity. Taken into account the preliminary stability data and the results of this collaborative study, the 3 batches of candidate BRP were adopted in June 2010 by the Commission of the Ph. Eur. as Heparin low-molecular-mass for assay BRP batches 6, 7 and 8.

The European Pharmacopoeia (Ph. Eur.) monographs for the water-soluble cellulose ethers require viscosity determination, either in the "Tests" section or in the non-mandatory "Functionality-related characteristics" section. Although the derivatives are chemically closely related and used for similar applications, the viscosity tests strongly differ. Some monographs generically speak of the rotating viscometer method (2.2.10) and a fixed shear rate (e.g. 10 s-1), which would necessitate an absolute measuring system, while others recommend the capillary viscometer method for product grades of less than 600 mPa∙s and the rotating viscometer method and given operating conditions for grades of higher nominal viscosity. Viscometer methods also differ between the United States Pharmacopeia/National Formulary (USP/NF) and the Japanese Pharmacopoeia (JP) monographs. In addition, for some cellulose ethers the tests sometimes diverge from one pharmacopoeia to the other, although the three compendiums are in a harmonisation process. But the main issue is that the viscometer methods originally employed by the product manufacturers are often not those described in the corresponding monographs and generally vary from one manufacturer to the other. The aim of this study was therefore to investigate whether such a situation could invalidate the present pharmacopoeial requirements. 2 per cent solutions of several viscosity grades of hydroxyethylcellulose, hypromellose and methylcellulose were prepared and their (apparent) viscosity determined using both relative and absolute viscometer methods. The viscometer method used not only affects the measured viscosity but experimental values generally do not correspond to the product nominal viscosities. It emerges that, in contrast to Newtonian solutions (i.e. those of grades of up to ca. 50 mPa∙s nominal viscosity), some of the viscometer methods currently specified in the monographs are not able unambiguously to characterise the grades exhibiting non-Newtonian behaviour. It is also concluded that, unless the various manufacturers redefine their product viscosity grades using a single compendial test, two strategies could be adopted, both based on the operating conditions specified in the labeling (i.e those of the manufacturer), the test appearing either in the mandatory section if this is acceptable to the pharmacopoeia (like in some USP/NF monographs) or, for the Ph. Eur., in the "Functionality-related characteristics" section.

This paper presents in-vitro metoprolol release from four different extended-release (ER) formulations, i.e. Metoprolol GEA® Retard, Logimax® forte, Metoprolol Sandoz® and Seloken ZOC® in the presence of 10 to 40% (v/v%) ethanol at pH 1.2 and pH 6.8. The assay of metoprolol in the dissolution media was performed by reversed phase liquid chromatography (RP-LC) using a mixture of methanol and 100 mM phosphate buffer (pH 3.5) in 40:60 ratio as eluent. The dissolution data showed that the metoprolol contents of Metoprolol Sandoz® and Seloken ZOC® were released fast in the presence of 20% ethanol at the investigated conditions, while the other products demonstrated much more stability against ethanol. Unexpectedly it was discovered that the release of metoprolol from Metoprolol GEA® Retard and to some extent also from Logimax® forte decreased in the ethanol containing media.