Nicolas Simon

Dr. Nicolas Simon

Department of Clinical Pharmacology, CAP-TV, Aix-Marseille University, APHM, INSERM, IRD, SESSTIM, Hop Sainte Marguerite, 13000 Marseille, France
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Research Focus & Metrics

Academic Career Length

31Years (1996-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 November 2019 in Journal of Clinical Oncology
Verified
Journal Article
Open access
JDJean Donadieu
Jean Donadieu
ILIslam Amine LARABI
Islam Amine LARABI
MTMathilde Tardieu
Mathilde Tardieu
JVJohannes Visser
Johannes Visser
CHCaroline Hutter
Caroline Hutter
SHSébastien Héritier
Sébastien Héritier
PURPOSE: Off-label use of vemurafenib (VMF) to treat BRAFV600E mutation–positive, refractory, childhood Langerhans cell histiocytosis (LCH) was evaluated. PATIENTS AND METHODS: Fifty-four patients from 12 countries took VMF 20 mg/kg/d. They were classified according to risk organ involvement: liver, spleen, and/or blood cytopenia. The main evaluation criteria were adverse events (Common Terminology Criteria for Adverse Events [version 4.3]) and therapeutic responses according to Disease Activity Score. RESULTS: LCH extent was distributed as follows: 44 with positive and 10 with negative risk organ involvement. Median age at diagnosis was 0.9 years (range, 0.1 to 6.5 years). Median age at VMF initiation was 1.8 years (range, 0.18 to 14 years), with a median follow-up of 22 months (range, 4.3 to 57 months), whereas median treatment duration was 13.9 months (for 855 patient-months). At 8 weeks, 38 complete responses and 16 partial responses had been achieved, with the median Disease Activity Score decreasing from 7 at diagnosis to 0 ( P < .001). Skin rash, the most frequent adverse event, affected 74% of patients. No secondary skin cancer was observed. Therapeutic plasma VMF concentrations (range, 10 to 20 mg/L) seemed to be safe and effective. VMF discontinuation for 30 patients led to 24 LCH reactivations. The blood BRAFV600E allele load, assessed as circulating cell-free DNA, decreased after starting VMF but remained positive (median, 3.6% at diagnosis, and 1.6% during VMF treatment; P < .001) and was associated with a higher risk of reactivation at VMF discontinuation. None of the various empirical therapies (hematopoietic stem-cell transplantation, cladribine and cytarabine, anti-MEK agent, vinblastine, etc) used for maintenance could eradicate the BRAFV600E clone. CONCLUSION: VMF seemed safe and effective in children with refractory BRAFV600E-positive LCH. Additional studies are needed to find effective maintenance therapy approaches.

1 January 2012 in Clinical Pharmacokinetics
Verified
Journal Article
Closed access
PDF file
AMAmélie Marsot
Amélie Marsot
ABAudrey Boulamery
Audrey Boulamery
BBBernard Bruguerolle
Bernard Bruguerolle
Nicolas SimonNicolas Simon
Nicolas Simon

23 July 2015 in Current Pharmaceutical Design
Verified
Journal Article
Closed access
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LCLouise Carton
Louise Carton
OCOlivier Cottencin
Olivier Cottencin
MLMaryse Lapeyre-Mestre
Maryse Lapeyre-Mestre
Pierre A. GeoffroyPierre A. Geoffroy
Pierre A. Geoffroy
JFJonathan Favre
Jonathan Favre
BRBenjamin Rolland
Benjamin Rolland
Introduction: New antipsychotics continuously arrive on the market, which thereby influences the approved and off-label prescribing (OLP) schemes. We aimed to identify the recent trends in the OLP of antipsychotics. We conducted a literature review based on three different populations: adult, pediatric, and elderly patients. Methods: A literature search was performed in the PubMed and ScienceDirect databases using the following keyword algorithm: “offlabel” AND (“antipsychotic*” OR “neuroleptic*”). The period investigated ranged from January 2000 to January 2015. Only Englishwritten pharmacoepidemiological studies were included. Results: Seventy-seven relevant results were identified. Among adults, OLP consisted of 40 to 75% of all antipsychotic prescriptions. The main indications were mood disorders, anxiety disorders, insomnia and agitation. Quetiapine was the most frequently prescribed offlabel antipsychotic, especially for anxiety and insomnia. Among children, OLP was estimated between 36 and 93.2% of all antipsychotic prescriptions. Risperidone and aripiprazole were primarily used and were most often prescribed for attention deficit hyperactivity disorder, anxiety, or mood disorders. Among elderly individuals, OLP consisted of 22 to 86% of all antipsychotic prescriptions. Antipsychotic OLP was particularly frequent for agitation; however, a recent decrease in this OLP was identified. Discussion: Antipsychotics have largely been prescribed off-label in recent years. The types of antipsychotic OLP practices differ according to the age category of patients. OLP is often used in cases of therapeutic dead-ends or for specific disorders with few or no currently approved medications. However, other OLP practices only reflect temporary prescription trends for mild symptoms, which may induce safety concerns.

1 February 2006 in Current Pharmaceutical Design
Verified
Journal Article
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CMChristophe Morin
Christophe Morin
Nicolas SimonNicolas Simon
Nicolas Simon
Evidence obtained over the past two decades shows that reactive oxygen species (ROS) are involved in brain lesions, including those due to cerebral ischemia-reperfusion. The mitochondria are the primary intracellular source of ROS, as they generate huge numbers of oxidative-reduction reactions and use massive amounts of oxygen. When anoxia is followed promptly by reperfusion, the resulting increase in oxygen supply leads to overproduction of ROS. In ischemic tissues, numerous studies have established a direct role for ROS in oxidative damage to lipids, proteins, and nucleic acids. Thus, mitochondria are both the initiator and the first target of oxidative stress. Mitochondrial damage can lead to cell death, given the role for mitochondria in energy metabolism and calcium homeostasis, as well as the ability of mitochondria to release pro-apoptotic factors such as cytochrome C and apoptosis-inducing factor (AIF). This review discusses possible mitochondrion-targeted strategies for preventing ROS-induced injury during reperfusion. The sequence of events that follow oxidative damage provides the outline for the review: thus, we will discuss protection of oxidative phosphorylation, mitochondrial membrane integrity and fluidity, and antioxidant or mild-uncoupling strategies for diminishing ROS production. Among mechanisms of action, we will describe the modulation of mitochondrial permeability transition pore (MPTP) opening, which may not only operate as a physiological Ca2+ release mechanism, but also contribute to mitochondrial deenergization, release of pro-apoptotic proteins, and protection by ischemic preconditioning (IPC). Finally, we will review genetic strategies for controlling apoptotic protein expression, stimulating mitochondrial oxidative defences, and increasing mitochondrial proliferation.

17 January 2019 in Clinical Pharmacokinetics
Verified
Journal Article
Open access
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PCPieter J. Colin
Pieter J. Colin
Karel AllegaertKarel Allegaert
Karel Allegaert
ATAlison H. Thomson
Alison H. Thomson
Daniel Johannes TouwDaniel Johannes Touw
Daniel Johannes Touw
MDMichael Dolton
Michael Dolton
DEDouglas J. Eleveld
Douglas J. Eleveld
Uncertainty exists regarding the optimal dosing regimen for vancomycin in different patient populations, leading to a plethora of subgroup-specific pharmacokinetic models and derived dosing regimens. We aimed to investigate whether a single model for vancomycin could be developed based on a broad dataset covering the extremes of patient characteristics. Furthermore, as a benchmark for current dosing recommendations, we evaluated and optimised the expected vancomycin exposure throughout life and for specific patient subgroups.

1 July 2002 in Clinical Neuropharmacology
Verified
Journal Article
Closed access
BBBernard Bruguerolle
Bernard Bruguerolle
Nicolas SimonNicolas Simon
Nicolas Simon
The existence of circadian rhythms and their implication in many pathologic processes have been underlined in several diseases but have not been evaluated in Parkinson's disease. The aim of this paper is to review diurnal variations of clinical, biologic, or experimental factors described with Parkinson's disease. Clinical data often report daily fluctuations of motor activity pattern, but the effect of the stage of the disease and the respective roles of drugs are difficult to evaluate. Sleep disturbances in Parkinson's disease patients also reveal alterations of circadian rhythms. Autonomic dysfunction, described in Parkinson's disease, reveals numerous alterations in circadian regulations including loss of circadian rhythm of blood pressure, increased diurnal blood pressure variability, and postprandial hypotension. Many biologic indices such as cortisol, catecholamines, and melatonin are also altered. Circadian rhythms in dopaminergic systems as well as possible daily fluctuations in kinetics of drug treatments are likely involved in such variations. Few clinical studies have been devoted to circadian patterns of drug response. As for other diseases where biologic rhythms are concerned Parkinson's disease therapy may be influenced by further understanding of circadian influence.