Commercial specifications for a new biotherapeutic product are a critical component of the product's overall control strategy that ensures safety and efficacy. This paper describes strategies for setting commercial specifications as proposed by a consortium of industry development scientists. The specifications for some attributes are guided by compendia and regulatory guidance.
View Article and Find Full Text PDFEarly-phase specifications are established to ensure that materials used in clinical studies have appropriate product quality, reducing the risk of harm to patients. Currently, guidance is available for specification setting practices at commercial phase. With very limited data and manufacturing experience available, it is not possible to fully align to these expectations at the start of clinical trials.
View Article and Find Full Text PDFThe characterization of orally-delivered peptide pharmaceuticals presents several challenges to analytical methods in comparison to characterization of conventional small-molecule drugs. These challenges include the analysis and characterization of difficult-to-separate impurities, secondary structure, the amorphous solid-state form, and the integrity of enteric-coated drug delivery systems. This work presents the multidisciplinary analytical characterization of a parathyroid hormone (PTH) peptide active pharmaceutical ingredient (API) and an oral formulation of this API within enteric-coated sucrose spheres.
View Article and Find Full Text PDFWe describe structural properties and biological activities of two related O-glycosylated peptide toxins isolated from injected (milked) venom of Conus striatus, a piscivorous snail that captures prey by injecting a venom that induces a violent, spastic paralysis. One 30 amino acid toxin is identified as kappaA-SIVA (termed s4a here), and another 37 amino acid toxin, s4b, corresponds to a putative peptide encoded by a previously reported cDNA. We confirm the amino acid sequences and carry out structural analyses of both mature toxins using multiple mass spectrometric techniques.
View Article and Find Full Text PDFThe beta-thymosins have been known as actin-sequestering proteins, but now are recognized as molecules with multiple and diverse intracellular and extracellular functions. Two closely related proteins, beta-thymosin(His) and beta-thymosin(Gln), have been de novo sequenced by top-down mass spectrometry in the common neurobiology model, Aplysia californica. As determined by nanoelectrospray quadrupole-enhanced Fourier-Transform mass spectrometry with collisionally activated and electron-capture dissociations, both of these Aplysia beta-thymosins are acetylated and differ by a single residue in the central actin-binding domain.
View Article and Find Full Text PDFMass spectrometry has emerged as an important technique for conotoxin analysis due to its capacity for selective, sensitive, information-rich analyses. Using liquid chromatography/mass spectrometry, Conus venom can be fractionated and the peptides surveyed for specific post-translational modifications, indicating those toxin components likely to have an important biological function. With Conus striatus and Conus victoriae venom as models, bromination, carboxylation and glycosylation modifications are identified through characteristics such as isotopic distribution and labile losses observed during mass spectrometric analysis.
View Article and Find Full Text PDFVenom peptides from two species of fish-hunting cone snails (Conus striatus and Conus catus) were characterized using microbore liquid chromatography coupled with matrix-assisted laser desorption/ionization-time of flight-mass spectrometry and electrospray ionization-ion trap-mass spectrometry. Both crude venom isolated from the venom duct and injected venom obtained by milking were studied. Based on analysis of injected venom samples from individual snails, significant intraspecific variation (i.
View Article and Find Full Text PDFA combination of cDNA cloning and detailed mass spectrometric analyses was employed to identify novel conotoxins from Conus victoriae. Eleven conotoxin sequences were determined using molecular methods: one belonging to the A superfamily (Vc1.1), six belonging to the O superfamily (Vc6.
View Article and Find Full Text PDFThe crustacean stomatogastric ganglion (STG) is modulated by both locally released neuroactive compounds and circulating hormones. This study presents mass spectrometric characterization of the complement of peptide hormones present in one of the major neurosecretory structures, the pericardial organs (POs), and the detection of neurohormones released from the POs. Direct peptide profiling of Cancer borealis PO tissues using matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) mass spectrometry (MS) revealed many previously identified peptides, including proctolin, red pigment concentrating hormone (RPCH), crustacean cardioactive peptide (CCAP), several orcokinins, and SDRNFLRFamide.
View Article and Find Full Text PDFA novel potassium channel antagonist has been purified from the defensive mucus secreted by Calliostoma canaliculatum, a marine snail found in the temperate coastal waters of the western Pacific. The toxin is expelled from the hypobranchial gland as part of a defensive response and is contained within a viscous matrix that minimizes dilution and degradation. The active compound was isolated by multistage microbore HPLC separations followed by bioactivity assays.
View Article and Find Full Text PDFNeuropeptides are a complex set of signaling molecules produced through enzymatic cleavages from longer prohormone sequences. The most common cleavage sites in prohormones are basic amino acid residues; however, processing is observed at non-basic sites. Cleavage at Leu-Leu sequences has been observed in three Aplysia californica prohormones.
View Article and Find Full Text PDFLike all members of the genus, Conus californicus has a specialized venom apparatus, including a modified radular tooth, with which it injects paralyzing venom into its prey. In this paper the venom duct and its connection to the pharynx, along with the radular sac and teeth, were examined using light and transmission electron microscopy. The general anatomy of the venom apparatus resembles that in other members of the genus, but several features are described that have not been previously reported for other species.
View Article and Find Full Text PDFThe orcokinins are a family of neuropeptides recently isolated from several crustacean species. We found orcokinin-like immunoreactivity in the stomatogastric nervous systems and pericardial organs of three decapod crustacean species, Homarus americanus, Cancer borealis, and Panulirus interruptus. The neuropil of the stomatogastric ganglion was stained in adults of all three species as well as in embryonic and larval H.
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