Design of in vitro skin permeation studies according to the EMA guideline on quality of transdermal patches

Transdermal patches and medicated plasters are designed to sustain efficacious systemic or loco-regional drug concentrations, respectively. In both cases, drug skin permeation is a critical attribute from the early stage of the pharmaceutical development. In 2014, the EMA introduced the "Guideline on the quality of transdermal patches", in which the importance of equivalence of drug fluxes in in vitro skin permeation study was particularly emphasized to generic or abridged applications for the marketing authorization or manage dossier variations during the product cycle life. Moving from experimental data, this work provides information on the set-up of such studies and the statistical evaluation of obtained fluxes. In particular, the impact of the inter-sample variability on the equivalence assessment was deeply investigated by using formulation pairs containing propranolol, diclofenac or nitroglycerine. The main outputs of the work were attributable to the definition of the acceptability interval and number of replicates to be performed. As an example, the equivalence of two propranolol patches (flux variability lower than 25%) can be assessed using six replicas and a confidence limit within the 0.8-1.25 range (alpha = 0.05; power 90%). In contrast, the equivalence of diclofenac plasters, which exhibit a variability near the 50%, can be demonstrated increasing the number of replicas (i.e., 20 skin samples) for each formulation and widening the acceptance range according to the statistical approach proposed in the work

Regulatory aspects and quality controls of polymer-based parenteral long-acting drug products: the challenge of approving copies

To assure the safety and the efficacy of a medicinal product, quality and batch-to-batch reproducibility need to be guaranteed. In the case of parenteral long-acting products, the European Union (EU) and US Regulatory Authorities provide different indications, from the classification to the in vitro release assays related to such products. Despite their relevance, there are few in vitro experimental set-ups enabling researchers to discriminate among products with different in vivo behavior. Consequently, most copies are authorized through hybrid instead of generic applications. Here, we review the actual regulatory frameworks to evaluate the in vitro release tests of polymer-based long-acting parenterals to highlights the directions followed by the Regulatory Agencies in the USA and EU

Continuous Glucose Monitoring in Preterm Infants: The Role of Nutritional Management in Minimizing Glycemic Variability

Glycemic variability (GV) is common in preterm infants. In the premature population, GV is a risk factor for morbidity and mortality. Both hypo- and hyperglycemia can impair neurodevelopment. We investigated the impact of continuous versus intermittent tube enteral feeding on GV. In our prospective observational study, 20 preterm infants with a gestational age ≤ 34 weeks at either continuous or intermittent bolus full enteral feeding. For five days, continuous glucose monitoring (CGM) was utilized, which was achieved through the subcutaneous insertion of a sensor. A total of 27,532 measurements of blood glucose were taken. The mean amplitude of glycemic excursions did not differ between the two cohorts statistically. Continuous feeding resulted in higher positive values, increasing the risk of hypo- and hyperglycemia. Subjects who were small for their gestational age had a higher standard deviation during continuous feeding (p = 0.001). Data suggest that intermittent bolus nutrition is better for glycemic control than continuous nutrition. Nutritional management optimization of preterm infants appears to be critical for long-term health. In the future, CGM may provide a better understanding of the optimal glucose targets for various clinical conditions, allowing for a more personalized approach to management

Copper induces Cu-ATPase ATP7A mRNA in a fish cell line, SAF1

Copper transporting ATPase, ATP7A, is an ATP dependent copper pump present in all vertebrates, critical for the maintenance of intracellular and whole body copper homeostasis. Effects of copper treatment on ATP7A gene expression in fibroblast cells (SAF1) of the sea bream (Sparus aurata) were investigated by qRT-PCR and by a medium density microarray from a closely related species, striped sea bream (Lithognathus mormyrus). To discriminate between the effects of Cu and other metals, SAF1 cells were exposed to sub-toxic levels of Cu, Zn and Cd. Expression of Cu homeostasis genes copper transporter 1 (CTR1), Cu ATPase (ATP7A), Cu chaperone (ATOX1) and metallothionein (MT) together with the oxidative stress markers glutathione reductase (GR) and Cu/Zn superoxide dismutase (CuZn/SOD) were measured 0, 4 and 24 hours post-exposure by qRT-PCR. Microarray was conducted on samples from 4 hours post Cu exposure. Cu, Zn and Cd increased MT and GR mRNA levels, while only Cu increased ATP7A mRNA levels. Microarray results confirmed the effects of Cu on ATP7A and MT and in addition showed changes in the expression of genes involved in protein transport and secretion. Results suggest that ATP7A may be regulated at the transcriptional level directly by Cu and by a mechanism that is different from that exerteted by metals on MT genes

Fixed Versus Free Combinations of Antihypertensive Drugs: Analyses Of Real-World Data Of Persistence With Therapy In Italy

Purpose: To analyse the pattern of use and cost of antihypertensive drugs in new users in an Italian population, and explore the patient/treatment factors associated with the risk of therapy discontinuation. Patients and methods: In this retrospective study, information was collected from a population-based electronic primary-care database. Persistence with medication use 1 year from therapy initiation was evaluated for each user using the gap method. Each new user was classified according to his/her pattern of use as: \u201ccontinuer\u201d, \u201cdiscontinuer\u201d \u201cswitching\u201d or \u201cadd-on\u201d. A Cox regression model was used to analyse the factors influencing therapy discontinuation. Primary-care costs comprised specialists\u2019 visits, diagnostic procedures and pharmacologic therapies. Results: Among 14,999 subjects included in persistence analyses, 55.1% of cases initially started on monotherapy were classified as discontinuers vs 36.5% of cases taking combination therapy (42.3% vs 32.7%, respectively, for free and fixed combinations, P < 0.01). Old age, high cardiovascular risk and being in receipt of fixed-combination therapy were associated with greater persistence. Overall, the primary-care cost/person/year of hypertension management was 3c\u20ac95.3 (IQR, 144.9). The monotherapy cost was \u20ac88 per patient (IQR, 132.9), and that for combination therapy was \u20ac151\ub1148.3. The median cost/patient with a fixed combination was lower than that for a free combination (\u20ac98.4 (IQR, 155.3) and \u20ac154.9 (IQR, 182.6), respectively). Conclusion: The initial type of therapy prescribed influences persistence. Prescribing fixed combinations might be a good choice as initial therapy

Simulation data for an estimation of the maximum theoretical value and confidence interval for the correlation coefficient

The data presented in this article are related to the article titled "Molecular Dynamics as a tool for in silico screening of skin permeability" (Rocco et al., 2017) [1]. Knowledge of the confidence interval and maximum theoretical value of the correlation coefficient r can prove useful to estimate the reliability of developed predictive models, in particular when there is great variability in compiled experimental datasets. In this Data in Brief article, data from purposely designed numerical simulations are presented to show how much the maximum r value is worsened by increasing the data uncertainty. The corresponding confidence interval of r is determined by using the Fisher r\u2192Z transform

Sex-dependent effects of developmental lead exposure in Wistar rats: Evidence from behavioral and molecular correlates

Lead (Pb) exposure in early life affects brain development resulting in cognitive and behavioral deficits. Epidemiologic and experimental evidence of sex as an effect modifier of developmental Pb exposure is emerging. In the present study, we investigated Pb effects on behavior and mechanisms of neuroplasticity in the hippocampus and potential sex differences. To this aim, dams were exposed, from one month pre-mating to offspring weaning, to Pb via drinking water at 5 mg/kg body weight per day. In the offspring of both sexes, the longitudinal assessment of motor, emotional, and cognitive end points was performed. We also evaluated the expression and synaptic distribution of N-methyl-D-Aspartate receptor (NMDA) and ff-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor subunits at post-natal day (pnd) 23 and 70 in the hippocampus. Neonatal motor patterns and explorative behavior in offspring were affected in both sexes. Pb effects in emotional response and memory retention were observed in adult females only, preceded by increased levels of GluN2A and GluA1 subunits at the post-synapse at pnd 23. These data suggest that Pb exposure during development affects glutamatergic receptors distribution at the post-synaptic spine in females. These effects may contribute to alterations in selected behavioral domains