Pharmeuropa bio & scientific notes最新文献

This publication describes the outcome of a project to develop a replacement European Pharmacopoeia (Ph. Eur.) Biological Reference Preparation (BRP) for Human tetanus immunoglobulin (TIg) as well as for the World Health Organization (WHO) International Standard (IS) for Tetanus Immunoglobulin, Human. Bulk TIg was kindly provided by a European manufacturer and was used to prepare the candidate standard. The candidate standard was freeze-dried and calibrated in an international collaborative study jointly co-ordinated by the Medicines & Healthcare products Regulatory Agency (MHRA) and the European Directorate for the Quality of Medicines & HealthCare (EDQM, Council of Europe). The results of this study show that there was good agreement between laboratories for the potency estimates obtained for the candidate standard relative to the current WHO IS/Ph. Eur. BRP. The study also demonstrated that the candidate standard is suitable for use in Ph. Eur. assays for potency testing of TIg products and there was good agreement in the potency estimates obtained using the different assay methods included in the study. Accelerated degradation studies performed at the MHRA over a period of 4 years suggest that the freeze-dried candidate standard will be very stable. The candidate standard was established as Ph. Eur. BRP for Human tetanus immunoglobulin, batch 2 with an assigned potency of 45 IU/ampoule. The same preparation was also adopted by the WHO Expert Committee on Biological Standardization (ECBS) to serve as the WHO 2nd IS for Tetanus Immunoglobulin, Human (13/240).

An international collaborative study was run within the framework of the Biological Standardisation Programme (BSP) of the Council of Europe and the Commission of the European Union to establish replacement batches for European Pharmacopoeia (Ph. Eur.) Heparin Low-Molecular-Mass (LMM) for calibration Chemical Reference Substance batch 3 (CRS3) used for the characterisation of LMM heparins by high performance size-exclusion chromatography. Two candidate batches (A, cCRS4 and B, cCRS5) were filled using the same material as the existing official calibrants, adopted with either an assigned number-average molecular mass (Mna) or a broad standard table (BST). Fifteen laboratories evaluated the suitability of these candidate batches for use as calibrants with the pharmacopoeial dual refractive index/ultraviolet (RI/UV) detector calibration method, as well as with a modified mobile phase and the BST calibration method. Seven preparations of LMM heparin were tested. The results confirmed that the proposed batches are suitable for use with the same characteristic Mna as CRS3 and with the BST established for the World Health Organization (WHO) 2^nd International Standard (IS). The BST calibration method gave comparable results to the RI/UV method, while showing better reproducibility, being easier to perform and requiring no calibrant with UV absorbance. The modified mobile phase had no impact on the calculated values while improving separation between the calibrant and salt peaks. The two candidate batches were adopted as Ph. Eur. Heparin LMM for calibration CRS batches 4 and 5, respectively, with the assigned Mna value of 3800 and a BST. In anticipation of the depletion of the calibrant required for use with the RI/UV method, and taking into account the unlikely procurement of a new lot of suitable starting material, it was recommended to include the BST method in Ph. Eur. monograph 0828, Heparins, low-molecular-mass. In order to improve peak separation, it was also recommended to include the use of ammonium acetate solution as mobile phase in the monograph, both for the Ph. Eur. RI/UV and the proposed BST calibration methods. Further to this study, Ph. Eur. monograph 0828 was revised to replace the RI/UV method by the BST method. This contributed to the harmonisation of methods across regions, thereby facilitating a concerted global action for the development and establishment of the next batches of calibrants for the quality control of LMM heparins.

Chromogenic assay discrepancies were reported at General European Official Medicines Control Laboratories Network (GEON) meetings by laboratories testing FVIII-products. The objectives of the present investigation were to carry out a controlled collaborative study to examine these reports and to delineate the reasons for these discrepancies by assessing affected and unaffected FVIII products. The laboratories followed a strict study protocol, which included assessing their own individual observed factor X (FX) activation times, i.e. the time to reach 50% of maximal FX activation (T_1/2), for each chromogenic kit. This measurement was used, in parallel with the kit manufacturers' prescribed FX activation times, to assess the performance of the chromogenic potency assays on FVIII test products. This study confirmed a significant discrepancy between Coatest® and Coamatic® kits and between Siemens and Coamatic® kits when the kit manufacturers' prescribed T_1/2 incubation times were followed. Coamatic® kits tended to produce higher potencies than the Coatest® or Siemens kits. Furthermore, FX activation assays revealed marked differences between individual laboratories for all three chromogenic kits in the observed T_1/2 incubation times, which also did not correspond to the prescribed T_1/2 incubation times. The resulting differences in potency between kits, in some cases, were significantly reduced when using the actual observed T_1/2 incubation times instead of the prescribed T_1/2 incubation times. The study showed that FVIII potency discrepancies can occur between chromogenic kits. To compensate for this, laboratories should ideally perform FX activation curves for each new chromogenic kit in order to determine the correct observed T_1/2 incubation times, which can then be used to determine FVIII potencies in therapeutic concentrates.

The viral genome titre is universally used for the dosing of adeno-associated virus (AAV)-based vectors used for gene therapy. To standardise this determination, the development of a common method would be valuable to facilitate comparison of viral doses used in the clinic and in the subsequent quality control of the products. A collaborative study was initiated by the Gene Therapy Working Group of the General European Official Medicines Control Laboratories Network in order to validate a qPCR-based method targeting the ITR2 sequence common to a broad variety of AAV vectors, independently from the serotype of the capsid or from the specific transgene. Five preparations of AAV vectors from various serotypes, including the AAV2/2 (RSS2) and AAV2/8 (RSS8) Reference Standard Stocks (American Type Culture Collection, USA) were used in the study. A plasmid carrying the ITR2 sequence was used to prepare standard curves. Its digestion outside the ITR regions facilitated melting of the hairpin ITR sequence during PCR, allowing better accessibility to the DNA polymerase. The results show that this qPCR method is satisfactory in terms of accuracy and precision. The reproducibility is also acceptable when compared with other similar studies, as it was shown previously that titres obtained by qPCR generally show higher inter-laboratory variability. The use of RSS2 or RSS8 as normalisation control in each assay demonstrated a promising help to identify potential sources of variation in a given laboratory or to smooth out inter-laboratory variations, thus improving reproducibility.

The manufacture of advanced therapy medicinal products (ATMPs) is critically impacted by the quality of the raw materials (RMs) used. Following the need expressed by stakeholders to establish a certification scheme for biological RMs used in the manufacture of ATMPs, the European Pharmacopoeia (Ph. Eur.) Cell Therapy Products Working Party (CTP WP) conducted an informal investigation with the aim of issuing a technical opinion on the feasibility of such a certification scheme. Seven RM Drug Master Files were reviewed for compliance of the RM with Ph. Eur. general chapter 5.2.12. Raw materials of biological origin for the production of cell-based and gene therapy medicinal products by members of the CTP WP who were representatives of competent authorities and experienced in the evaluation of RMs for ATMPs. This article presents the results of these case studies, including the potential benefits and concerns identified by the experts. It was concluded that it would be technically feasible, albeit challenging, to set up a certification system for RMs of biological origin against chapter 5.2.12. Although the establishment of such a scheme is currently perceived by some CTP WP members as premature, it could potentially be beneficial for all stakeholders (RM manufacturers, ATMP manufacturers and assessors).

Several analytical procedures are described in the European Pharmacopoeia (Ph. Eur.) to determine total protein content. However, the method for the determination of protein content in therapeutic immunoglobulins prescribed in the Ph. Eur. monographs is the Kjeldahl method. The Kjeldahl method is time-consuming and requires the use of large amounts of hazardous reagents, which also results in the production of a large amount of hazardous chemical waste. The purpose of this work was to validate an alternative chromatographic method that requires no hazardous reagents and saves time, using the same instrumental conditions specified in the Ph. Eur. for the human immunoglobulin size-exclusion high-performance liquid chromatography (SEC-HPLC) molecular-size distribution assay. The chromatographic separation was achieved with a TSKgel G3000SW (600 × 7.5 mm, 10 µm) column, using an isocratic elution, with detection at 280 nm wavelength. The mobile phase consisted of an aqueous solution of 0.03 M disodium hydrogen phosphate dehydrate, 0.01 M sodium dihydrogen phosphate monohydrate, 0.2 M sodium chloride and 1 mM sodium azide. The protein content of the test samples was determined referring to a standard with a known protein concentration (i.e. Human immunoglobulin (molecular size) Biological Reference Preparation). The method was validated evaluating the characteristics precision and trueness according to the ICH Q2 guideline, and the goodness of linear fit for the signal response was assessed (given for information only). In addition, the equivalence of methods was evaluated with two one-sided t-tests (TOST) analysis with the Kjeldahl method mentioned in Ph. Eur. monographs on therapeutic immunoglobulins, and with Bland-Altman analysis of SEC-HPLC and manufacturers' data (Kjeldahl and biuret methods). The uncertainty of measurement was also calculated in order to evaluate the accuracy and quality of the results, thus facilitating a reliable compliance/non-compliance decision. Based on the outcome, the method is proposed as a suitable and convenient alternative for the determination of protein content in human immunoglobulins.

The European Pharmacopoeia (Ph. Eur.) monographs Human plasma for fractionation (0853) and Human plasma (pooled and treated for virus inactivation) (1646) require that plasma pools be tested for hepatitis C virus (HCV) RNA presence by nucleic acid amplification techniques (NAT) using a positive control at 100 IU/mL. HCV RNA for NAT testing BRP batch 1 was established in 1999 to this end. Due to dwindling stocks, the European Directorate for the Quality of Medicines & HealthCare (EDQM) organised a collaborative study to establish a replacement batch. The candidate material was produced as a lyophilised preparation of human plasma containing HCV genotype IA and calibrated against the 6th WHO International Standard for HCV RNA for NAT. Quantitative and qualitative HCV NAT assays based on real-time quantitative PCR techniques were used. Both types of assays were assessed separately. However, since no significant difference was observed between them, all results were pooled for the final potency assignment. Calculations based on Ct values were less variable than those based on end-point dilutions; they were thus used in the final combination. The combined overall mean potency was 959 IU/vial. An accelerated degradation study showed that the stability of the candidate material was satisfactory at the recommended long-term storage temperature, i.e. -20°C. The candidate BRP was established as Ph. Eur. HCV RNA for NAT testing BRP batch 2 by the Ph. Eur. Commission, with an assigned potency of 960 IU/vial. It will be available from the EDQM under catalogue number H0215000.

Due to the diminished stocks of the third batch of the European Pharmacopoeia (Ph. Eur.) Biological Reference Preparation (BRP) for Human immunoglobulin for electrophoresis, in 2020 the European Directorate for the Quality of Medicines & HealthCare (EDQM) initiated an international collaborative study for the establishment of a replacement batch. The study was run under the aegis of the Biological Standardisation Programme (BSP). Nineteen laboratories participated in the collaborative study to verify the suitability of the candidate reference preparations according to the Ph. Eur. monographs Human normal immunoglobulin for intravenous administration (0918), Human normal immunoglobulin for intramuscular administration (0338) and Human normal immunoglobulin for subcutaneous administration (2788) using the zone electrophoresis method with cellulose acetate and/or agarose as the testing medium. Capillary zone electrophoresis (CZE), a technique not yet included in monographs 0338, 0918 and 2788, was also used by some laboratories. The assignment of a value for immunoglobulin as a percentage of the total protein content could only be made for agarose electrophoresis and for CZE. The candidate preparation was found suitable for the intended purpose and was subsequently adopted by correspondence in May 2021 by the Ph. Eur. Commission as Human immunoglobulin for electrophoresis BRP batch 4 with an assigned range for immunoglobulin of 82.5 % to 87.8 % of the total protein content.

Weighing is a key activity in every quality control laboratory as it is one of the first steps in the preparation of samples and reagents for most analytical procedures. It is also critical because weighing errors will add up and propagate throughout the whole analysis, affecting the accuracy and precision of the reported results. A new general chapter, Balances for analytical purposes (2.1.7), has recently been published in the European Pharmacopoeia (Ph. Eur.). This new text sets out clear requirements for an instrument that is essential to every analytical procedure described within the pages of the Ph. Eur. This article explains in detail these requirements and generally reviews the other quantity-related requirements present in Ph. Eur. texts.

Progress towards standardisation of allergen products has been made in recent years. Nevertheless, no standardised test method to quantify the allergen content of grass pollen allergen products is available at present. One aim of the BSP090 project was to validate a quantitative assay for a major Timothy grass (Phleum pratense) pollen allergen, Phl p 5. Qualification of a candidate ELISA system was performed with regard to range, robustness and cross-reactivity in preliminary studies. The assay specifically detected Phl p 5 with a quantification range from 3.9 ng/mL to 62.5 ng/mL. Suitability to quantify recombinant and natural Phl p 5 was further assessed in a collaborative study including 14 laboratories in Europe and the USA. Precision and accuracy of the assay was satisfactory with 93% of calculated Phl p 5 concentrations and 100% of total recoveries being within the ± 30% acceptance range. Similar results were obtained for spike recoveries, with exclusion of the lowest concentration spike, showing spike recoveries exceeding the acceptance range for six laboratories. Inter-assay (repeatability) and inter-laboratory (reproducibility) variability were satisfactory, in the format used in the present study. Robustness towards different statistical methods for data analysis was demonstrated. In conclusion, the assay can easily be established in routine testing and results of the preliminary testing and collaborative study support the proposal of the assessed Phl p 5-specific ELISA as a European Pharmacopoeia general method.