Elaborating European Pharmacopoeia monographs for biotherapeutic proteins using substances from a single source.

For more than twenty years, the European Pharmacopoeia (Ph. Eur.) monographs for biotherapeutic proteins have been elaborated using the multisource approach (Procedure 1), which has led to robust quality standards for many of the first-generation biotherapeutics. In 2008, the Ph. Eur. opened up the way towards an alternative mechanism for the elaboration of monographs (Procedure 4-BIO pilot phase), which is applied to substances still under patent protection, based on a close collaboration with the Innovator company, to ensure a harmonised global standard and strengthen the quality of the upcoming products. This article describes the lessons learned during the P4-BIO pilot phase and addresses the current thinking on monograph elaboration in the field of biotherapeutics. Case studies are described to illustrate the standardisation challenges associated with the complexity of biotherapeutics and of analytical procedures, as well as the approaches that help ensure expectations are met when setting monograph specifications and allow for compatibility with the development of biosimilars. Emphasis is put on monograph flexibility, notably by including tests that measure process-dependent microheterogeneity (e.g. glycosylation) in the Production section of the monograph. The European Pharmacopoeia successfully concluded the pilot phase of the P4-BIO during its 156th session on 22-23 November 2016.

Further characterization of the tyrosine hydroxylase induction elicited by reserpine in the rat locus coeruleus and adrenals.

This study shows that reserpine causes a long lasting increase in the amount of protein and activity of tyrosine hydroxylase (TH) in central noradrenergic neurons of the locus coeruleus (LC) and in peripheral cells of the adrenal gland. In these structures, the drug effect appears to be reversible (maximum at day 2-4 after injection) and is entirely dose-dependent. Variations in TH activity were measured both in vitro in optimal enzymatic conditions and in vivo. Reserpine did not modify the ratio between activities measured in vivo and in vitro. But it decreased the specific activity of the enzyme as measured in homogenates of LC. The reversibility of the reserpine effect on all parameters studied appeared faster in adrenal than in central LC neurons. Reserpine did not change the activity and amount of TH in the region of the substantia nigra where dopaminergic neurons are located, except at a high dose (10 mg/kg): a significant elevation (+36%) of the TH protein amount was then observed 2 days after treatment. Moreover, reserpine did not influence the amount of neuron specific enolase in the LC region at a time when maximal effect was observed for TH, thus showing the biochemical specificity of this regulation. Concomitant injection of clonidine at two doses 30 min before (100?g/kg) and 3 h after (50?g/kg) reserpine administration did not affect the induction by reserpine alone. Thus, stimulation of LC noradrenergic cell firing resulting from reserpine administration is probably of negligible importance in the genesis of TH induction by this drug.

[Hypersomnia by isthmic lesion in cat. Study of the metabolism of cerebral monamines]. / Hypersomnie par lésion isthmique chez le chat. I. Etude du métabolisme des monoamines cérébrales

(1) A significant increase of 5-HT synthesis is observed in several areas of the cat brain 24 h after the bilateral destruction of the dorsal noradrenergic bundle in the isthmus. This stimulation of the synthesis was simultaneously observed at the level fo serotoninergic cell bodies (anterior part of the raphe system) and of 5-HT terminals (cortex, thalamus, mesencephalon, medulla oblongata). Conversely, a significant decrease of 5-HT synthesis was found in the caudal part of the raphe and in the hypothalamus. The possibility of a catecholaminergic control of 5-HT synthesis by neurons passing through the isthmus is discussed. (2) in the same experimental conditions, an important decrease of endogenous dopamine content without any subsequent change of noradrenaline concentration was observed in the thalamus, the geniculate body and the pons. This important decrease could be due to a greater utilization of dopamine into hypothetical dopaminergic terminals localized in these structures.