Regulatory challenges with biosimilars: an update from 20 countries.

The World Health Organization (WHO) issued guidelines for the regulatory evaluation of biosimilars in 2009 and has provided considerable effort toward helping member states implement the evaluation principles in the guidelines into their regulatory practices. Despite this effort, a recent WHO survey (conducted in 2019-2020) has revealed four main remaining challenges: unavailable/insufficient reference products in the country; lack of resources; problems with the quality of some biosimilars (and even more with noninnovator products); and difficulties with the practice of interchangeability and naming of biosimilars. The following have been identified as opportunities/solutions for regulatory authorities to deal with the existing challenges: (1) exchange of information on products with other regulatory authorities and accepting foreign licensed and sourced reference products, hence avoiding conducting unnecessary (duplicate) bridging studies; (2) use of a "reliance" concept and/or joint review for the assessment and approval of biosimilars; (3) review and reassessment of the products already approved before the establishment of a regulatory framework for biosimilar approval; and (4) setting appropriate regulatory oversight for good pharmacovigilance, which is essential for the identification of problems with products and establishing the safety and efficacy of interchangeability of biosimilars.

Isolation and structural characterization of Coryxin, a novel cyclic lipopeptide from Corynebacterium xerosis NS5 having emulsifying and anti-biofilm activity.

Herein we reported the structure and several properties of a new biosurfactants produced by Corynebacterium xerosis strain NS5. This strain was capable of producing a novel lipopeptide biosurfactant that we have named coryxin. The biosurfactant structure was characterized by using Fourier transform infrared spectroscopy (FTIR), Nuclear magnetic resonance spectroscopy (NMR), and Liquid chromatography-mass spectrometry (LC-MS). It contained a hydrophobic moiety of 3-hydroxydecanoic acid and a peptide part predicted as a sequence of seven amino acids including Asn-Arg-Asn-Gln-Pro-Asn-Ser. Coryxin lowered the surface tension of water to 31.4 mN/m, with a critical micelle concentration of 25mg/l. It was a strong emulsifier with an emulsification index of 61% against n-hexane. Coryxin showed antibacterial activity against test organisms belonging to Gram-positive and Gram-negative bacteria and disrupted preformed biofilms of Staphylococcus aureus (82.5%), Streptococcus mutans (80%), Escherichia coli (66%) and Pseudomonas aeruginosa (30%). In conclusion, microbial surfactant from C. xerosis exhibited inhibitory and disruptive activities against biofilm formation that could be of use in biofilm-related menace.

Bacterial contamination of single- and multiple-dose vials after multiple use and intravenous admixtures in three different hospitals in iran.

There is possibility of microbial contamination of any single-dose vials (SDVs), multiple-dose vials (MDVs) and admixtures (ADXs) during the preparation and injection to the patients that could be resulted in bloodstream infection. The goal of this study was to investigate the microbial contamination of MDVs and SDVs after multiple use and ADXs prepared by nursing staff in the treatment room versus those prepared by the hospital pharmacist in the clean room. The sterility of 43 opened MDVs and SDVs, 92 prepared ADXs in treatment room and 17 prepared ADXs in clean room were studied by membrane filtration method. Only one of 92 ADXs prepared in treatment room was contaminated with Bacillus subtilis (%1.1) and none of the ADXs prepared in clean room, MDVs and SDVs had microbial contamination. Although good sanitization practices and training of nurses could reduce the risk of microbial contamination in traditional units, using clean room for preparation of parenteral products could be the best strategy.

Structural characterization and surface activities of biogenic rhamnolipid surfactants from Pseudomonas aeruginosa isolate MN1 and synergistic effects against methicillin-resistant Staphylococcus aureus.

The aim of present work was to study chemical structures and biological activities of rhamnolipid biosurfactants produced by Pseudomonas aeruginosa MN1 isolated from oil-contaminated soil. The results of liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis revealed that total rhamnolipids (RLs) contained 16 rhamnolipid homologues. Di-lipid RLs containing C(10)-C(10) moieties were by far the most predominant congeners among mono-rhamnose (53.29 %) and di-rhamnose (23.52 %) homologues. Mono-rhamnolipids form 68.35 % of the total congeners in the RLs. Two major fractions were revealed in the thin layer chromatogram of produced RLs which were then purified by column chromatography. The retardation factors (R (f)) of the two rhamnolipid purple spots were 0.71 for RL1 and 0.46 for RL2. LC-MS/MS analysis proved that RL1 was composed of mono-RLs and RL2 consisted of di-RLs. RL1 was more surface-active with the critical micelle concentration (CMC) value of 15 mg/L and the surface tension of 25 mN/m at CMC. The results of biological assay showed that RL1 is a more potent antibacterial agent than RL2. All methicillin-resistant Staphylococcus aureus (MRSA) strains were inhibited by RLs that were independent of their antibiotic susceptibility patterns. RLs remarkably enhanced the activity of oxacillin against MRSA strains and lowered the minimum inhibitory concentrations of oxacillin to the range of 3.12-6.25 µg/mL.