Physicochemical and Biological Examination of Two Glatiramer Acetate Products.

Herein we compared 40 mg/mL lots of the active ingredient, glatiramer acetate, manufactured by Mylan/Natco to the active ingredient, glatiramer acetate in Copaxone (Teva Pharmaceuticals, Ltd., Netanya Israel) using physicochemical (PCC) methods and biological assays. No differences were seen between the Mylan/Natco and Teva lots with some low resolution release PCC assays (amino acid analysis, molecular weight distribution, interaction with Coomassie Brilliant Blue G-250). Changes in polydispersity between Mylan/Natco and Copaxone lots were found using size exclusion chromatography and the high resolution PCC method, known as Viscotek, and suggestive of a disparity in the homogeneity of mixture, with a shift towards high molecular weight polypeptides. Using RPLC-2D MALLS, 5 out of 8 Mylan/Natco lots fell outside the Copaxone range, containing a high molecular weight and high hydrophobicity subpopulation of polypeptides not found in Copaxone lots. Cation exchange chromatography showed differences in the surface charge distribution between the Copaxone and Mylan/Natco lots. The Mylan/Natco lots were found to be within Copaxone specifications for the EAE model, monoclonal and polyclonal binding assays and the in vitro cytotoxicity assay, however higher IL-2 secretion was shown for three Mylan/Natco lots in a potency assay. These observations provide data to inform the ongoing scientific discussion about the comparability of glatiramer acetate in Copaxone and follow-on products.

Compositional differences between Copaxone and Glatopa are reflected in altered immunomodulation ex vivo in a mouse model.

Copaxone (glatiramer acetate, GA), a structurally and compositionally complex polypeptide nonbiological drug, is an effective treatment for multiple sclerosis, with a well-established favorable safety profile. The short antigenic polypeptide sequences comprising therapeutically active epitopes in GA cannot be deciphered with state-of-the-art methods; and GA has no measurable pharmacokinetic profile and no validated pharmacodynamic markers. The study reported herein describes the use of orthogonal standard and high-resolution physicochemical and biological tests to characterize GA and a U.S. Food and Drug Administration-approved generic version of GA, Glatopa (USA-FoGA). While similarities were observed with low-resolution or destructive tests, differences between GA and USA-FoGA were measured with high-resolution methods applied to an intact mixture, including variations in surface charge and a unique, high-molecular-weight, hydrophobic polypeptide population observed only in some USA-FoGA lots. Consistent with published reports that modifications in physicochemical attributes alter immune-related processes, genome-wide expression profiles of ex vivo activated splenocytes from mice immunized with either GA or USA-FoGA showed that 7-11% of modulated genes were differentially expressed and enriched for immune-related pathways. Thus, differences between USA-FoGA and GA may include variations in antigenic epitopes that differentially activate immune responses. We propose that the assays reported herein should be considered during the regulatory assessment process for nonbiological complex drugs such as GA.

Functional effects of the antigen glatiramer acetate are complex and tightly associated with its composition.

Glatiramer acetate (Copaxone®; GA) is a non-biological complex drug for multiple sclerosis. GA modulated thousands of genes in genome-wide expression studies conducted in THP-1 cells and mouse splenocytes. Comparing GA with differently-manufactured glatiramoid Polimunol (Synthon) in mice yielded hundreds of differentially expressed probesets, including biologically-relevant genes (e.g. Il18, adj p<9e-6) and pathways. In human monocytes, 700+ probesets differed between Polimunol and GA, enriching for 130+ pathways including response to lipopolysaccharide (adj. p<0.006). Key differences were confirmed by qRT-PCR (splenocytes) or proteomics (THP-1). These studies demonstrate the complexity of GA's mechanisms of action, and may help inform therapeutic equivalence assessment.

The effect of whole-body, repetitive, inhomogeneous static magnetic field-exposure on the symptoms of experimental autoimmune encephalomyelitis in mice.

Experimental autoimmune encephalomyelitis (EAE) is a model for human multiple sclerosis (MS) in rodents. Static magnetic field (SMF)-exposure was shown to be beneficial in specific cases of inflammatory background, where it suppresses symptoms. The null-hypothesis was that animals with induced EAE exposed to SMF would show different seriousness of symptoms, than those in the sham-exposed control group. Three replicated series of repetitive, 30 min/day whole-body exposure to SMF with 477 mT peak-to-peak magnetic induction and 48 T/m lateral induction gradient was tested on female CSJLF1 mice with a mild, mouse spinal cord homogenate emulsion-induced EAE. Conventional scores of the animal response to EAE were compared between sham- and SMF-exposed groups of animals. Following pilot test we used 18 animals per group. Primary outcome measure was the daily group average of standard EAE scores. Results show that SMF-exposure has a strong, reproducible, and significantly beneficial effect up to 51.82% (p<0.001) over sham-exposure on the symptoms of EAE in the course of the 25 days of the experiment. This study aimed to build experimental research foundation for a later therapy option by applying SMF-exposure in the clinical management of MS.

Production of FK520 by Streptomyces tubercidicus.

The discovery of immunosuppressant compounds created the conditions for the successful transplantations. Effective immunosuppressant compounds were isolated from cultures of different microorganisms, among others macrolide type immunosuppressants, FK506 and FK520, were isolated from the fermentation broths of Streptomyces species. In this study a screening program was carried out to isolate microorganisms, which produce macrolide type immunosuppressant compounds. More than 40,000 actinomycete strains were investigated in the screening program comprising chemical, microbiological and PCR methods for the investigation of the cultures. Actinomycete strains with FK520 biosynthesizing ability were isolated in the program, which were identified as isolates of the Streptomyces tubercidicus species according to the taxonomical investigations. A part of the 31-O-demethyl-FK520 methyltransferase gene of the isolated S. tubercidicus was sequenced and it showed 88% homology to that of Streptomyces hygroscopicus. Till now strains of the Streptomyces hygroscopicus species were known to produce FK520 and this study proved that strains of other Streptomyces species have FK520 biosynthetic ability.

Biological and chemical detections in adsorbent layer for monitoring microbial production of primycin.

Primycin is a macrolide antibiotic complex produced in microbiological fermentation processes. The microbial production of primycin requires an in-process analytical method suitable for monitoring the level of the active agents. In this paper, a method fulfilling the described requirement is presented. This method consists of a simple, efficacious extraction step, an instrumental sample application followed by a high-performance thin-layer chromatographic separation in relatively short time and a quantitative chromatogram evaluation. A dipping technique, in a solution containing sulfuric acid followed by heating at 120 degrees C, is used for chromogen formation, resulting in an absorption maximum at 290 nm. A progress diagram of the fermentation obtained by this technique is compared with one obtained by a microbiological agar diffusion method. The bioautographic evaluation of the active spots in the chromatogram are also presented. By our TLC method, the group of the active primycin components in the fermentation broth and by-products formed during the fermentation can be well separated. The relative intensities of the different TLC spots provide some information on the formation of the active components.

Generation of useful insertionally blocked sterol degradation pathway mutants of fast-growing mycobacteria and cloning, characterization, and expression of the terminal oxygenase of the 3-ketosteroid 9alpha-hydroxylase in Mycobacterium smegmatis mc(2)155.

Integration of the pCG79 temperature-sensitive plasmid carrying Tn611 was used to generate libraries of mutants with blocked sterol-transforming ability of the sterol-utilizing strains Mycobacterium smegmatis mc(2)155 and Mycobacterium phlei M51-Ept. Of the 10,000 insertional mutants screened from each library, 4 strains with altered activity of the sterol-degrading enzymes were identified. A blocked 4-androstene-3,17-dione-producing M. phlei mutant transformed sitosterol to 23,24-dinorcholane derivatives that are useful starting materials for corticosteroid syntheses. A recombinant plasmid, pFJ92, was constructed from the genomic DNA of one of the insertional mutants of M. smegmatis, 10A12, which was blocked in 3-ketosteroid 9alpha-hydroxylation and carrying the transposon insertion and flanking DNA sequences, and used to isolate a chromosomal fragment encoding the 9alpha-hydroxylase. The open reading frame encodes the 383-amino-acid terminal oxygenase of 3-ketosteroid 9alpha-hydroxylase in M. smegmatis mc(2)155 and has domains typically conserved in class IA terminal oxygenases. Escherichia coli containing the gene could hydroxylate the steroid ring at the 9alpha position.

Inhibition of the MDR1 transporter by new phenothiazine derivatives.

The MDR1 transporter mediated efflux of different xenobiotics out of the cells serves as the most important mechanisms of the multidrug resistance in cancer cells, thus inhibition of the MDR1 transporter may increase the efficiency of anticancer drugs in the therapy. Here we describe some new phenothiazine derivatives, which possess strong in vitro MDR1 inhibitory activity. The effectiveness of the compounds on the MDR1 mediated calcein-AM efflux, ATPase activity, and colchicine resistance was proven by microplate assays and flow cytometry using recombinant and control cell lines. Some of these derivatives were more active than verapamil and one of them was at least as active as cyclosporin A. According to our results the new structural elements built in these phenothiazine type compounds increased their MDR1 inhibitory activity, which may serve as a basis of the development of an effective MDR1 inhibitor drug.