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The administration of aminoglycosides can induce nephrotoxicity or ototoxicity, which can be monitored through pharmacological therapeutic drug monitoring. However, there are cases of genetic predisposition to ototoxicity related to the MT-RNR1 gene, which may occur from the first administrations. Pharmacogenetic analysis recommendations have recently been proposed by the Clinical Pharmacogenetics Implementation Consortium (CPIC). The Francophone Pharmacogenetics Network (RNPGx) provides a bibliographic synthesis of this genetic predisposition, as well as professional recommendations. The MT-RNR1 gene codes for mitochondrial 12S rRNA, which constitutes the small subunit of the mitochondrial ribosome. Three variants can be identified: the variants m.1555A>G and m.1494C>T of the MT-RNR1 gene have a 'high' level of evidence regarding the risk of ototoxicity. The variant m.1095T>C has a 'moderate' level of evidence. The search for these variants can be performed in the laboratory if the administration of aminoglycosides can be delayed after obtaining the result. However, if the treatment is urgent, there is currently no rapid test available in France (a 'point-of-care' test is authorized in Great Britain). RNPGx considers: (1) the search for the m.1555A>G, m.1494C>T variants as 'highly recommended' and the m.1095T>C variant as 'moderately recommended' before the administration of an aminoglycoside (if compatible with the medical context). It should be noted that the level of heteroplasmy detected does not modify the recommendation; (2) pharmacogenetic analysis is currently not feasible in situations of short-term aminoglycoside administration, in the absence of an available analytical solution (rapid test to be evaluated in France); (3) the retrospective analysis in case of aminoglycoside-induced ototoxicity is 'recommended'; (4) analysis of relatives is 'recommended'. Through this summary, RNPGx proposes an updated review of the MT-RNR1-aminoglycoside gene-drug pair to serve as a basis for adapting practices regarding pharmacogenetic analysis related to aminoglycoside treatment., (Copyright © 2024 The Author(s). Published by Elsevier Masson SAS.. All rights reserved.)

Iron deficiency and iron-deficiency anemia are common medical conditions. Management of the etiology and iron supplementation are both necessary to treat this condition. Use of intravenous iron preparations is increasing due to its advantages over oral iron. Indeed, the total dose required can be provided in a single infusion, and it is more effective and increases hemoglobin levels more quickly than oral iron. Hypophosphatemia, sometimes severe, following intravenous iron administration, has been described in literature these past years, in particular with ferric carboxymaltose. We report here a case of severe hypophosphatemia with ferric carboxymaltose and carry out a literature review to determine the incidence of hypophosphatemia and to precise its clinical presentation, its pathophysiological mechanisms and its treatment. We found that hypophosphatemia is frequent with ferric carboxymaltose. Most of the time, there are no clinical manifestations, but cases of symptomatic osteomalacia have been described. Duration of hypophosphatemia is variable, from a few weeks to several months in case of prolonged administration. Hypophosphatemia owing to renal phosphate wasting is caused by an increase in intact fibroblast growth factor 23 (FGF-23) levels. However, the mechanism of ferric carboxymaltose- induced increase in intact FGF-23 is still unknown., (Copyright © 2021 Société française de pharmacologie et de thérapeutique. Published by Elsevier Masson SAS. All rights reserved.)

Pharmacogenetics, which concepts are known for a long time, is entering a new period at least as far as its practical applications for patients are concerned. In recent years there have been more and more initiatives to promote widespread dissemination, and health authorities are increasingly incorporating these concepts into drug labels. In France, the national network of pharmacogenetics (RNPGx) works to promote these activities, both with health actors (biologists, clinicians) and health authorities. This article reviews the current situation in France and the milestones of the year 2018. It highlights recent advances in this field, in terms of currently recommended analyses, sharing of information or technological developments, and the prospects for future developments in the near future from targeted pharmacogenetics to eventually preemptive approaches., (Copyright © 2019 Société française de pharmacologie et de thérapeutique. Published by Elsevier Masson SAS. All rights reserved.)

Adverse drug reactions are a significant cause of morbidity and mortality and represent a major burden on the healthcare system. Some of those reactions are immunologically mediated (hypersensitivity reactions) and can be clinically subdivided into two categories: immediate reactions (IgE-related) and delayed reactions (T-cell-mediated). Delayed hypersensitivity reactions include both systemic syndromes and organ-specific toxicities and can be triggered by a wide range of chemically diverse drugs. Recent studies have demonstrated a strong genetic association between human leukocyte antigen alleles and susceptibility to delayed drug hypersensitivity. Most notable examples include human leukocyte antigen (HLA)-B*57:01 allele and abacavir hypersensitivity syndrome or HLA-B*15:02 and HLA-B*58:01 alleles related to severe cutaneous reactions induced by carbamazepine and allopurinol, respectively. This review aims to explore our current understanding in the field of pharmacogenomics of HLA-associated drug hypersensitivities and its translation into clinical practice for predicting adverse drug reactions., (Copyright © 2017 Société française de pharmacologie et de thérapeutique. Published by Elsevier Masson SAS. All rights reserved.)

Type 1 Gaucher disease is a rare genetic disease characterized by enzymatic deficit leading to glucosylceramide overload in body tissues (lysosomal overload disease). Standard treatment is based on substitutive enzyme therapy by intravenous perfusion. A new drug for oral administration, eliglustat, was recently awarded marketing approval in Europe and the USA. Eliglustat acts by reducing the enzyme substrate. Eliglustat is mainly eliminated by a CYP2D6 pathway. CYP2D6 exhibits genetic variability or expression, leading to 20-fold differences in serum levels. In marketing approval documents, both the FDA and the EMA mention the requirement for CYP2D6 genotyping before prescribing eliglustat: the drug is contraindicated for ultra-rapid metabolizers (under-dosing inefficacy) and slow metabolizers should be given a 50% reduced daily dose (risk of overdose-related adverse effects). Finally, potential drug interactions (inhibition or induction of CYP2D6 or CYP3A40) are also dependent on CYP2D6 genotyping, such that prescribers must be aware of a patient's genotype before prescribing eliglustat., (Copyright © 2017 Société française de pharmacologie et de thérapeutique. Published by Elsevier Masson SAS. All rights reserved.)

Since the beginning of this century, information on pharmacogenetics appears in the summary of product characteristics (SPC) of drugs. Pharmacogenetic tests particularly concern the enzymes involved in the metabolism of drugs, among which P450 cytochromes. Some patients known as poor metabolisers eliminate some drugs more slowly, causing overdoses and adverse drug reactions (ADRs). The best-known examples are AVK and VKORC1-CYP2C9 or clopidogrel and CYP2C19. In the USA, the tests are recommended before the introduction of these drugs to prevent the occurrence of ADRs. Other tests are also commonly performed to address the toxicity of certain anticancer drugs (DPYD-capecitabine, UGT1A1-irinotecan, TPMT 6-mercaptopurine). Pharmacogenetic testing is also available to identify HLA loci that are very strongly associated with the occurrence of immuno-allergic reactions to a specific drug. The best-known example is HLA-B*5701, strongly associated with hypersensitivity to abacavir, and this test is now always prescribed before the instatement of this drug., (Copyright © 2016 Société française de pharmacologie et de thérapeutique. Published by Elsevier Masson SAS. All rights reserved.)

Objectives: To determine if and when prescription of psychotropic medication in women is modified by pregnancy., Method: Psychotropic prescription of 87 213 pregnant women affiliated with the French General Health System was examined. Period of analyses lasted 17 months to cover 4 months before and after pregnancy. A comparable cohort of 87 213 non pregnant women constituted the control group., Results: More than half of pregnant women to whom a psychoactive drug was prescribed were novel users during all three trimesters and after delivery. Prevalence of psychotropic medication before pregnancy is comparable to that of non-pregnant women. Rate of psychotropic medication during the peripartum stayed high, even though it decreased by half during the first trimester, showing a "pregnancy impact effect"., Conclusions: Data show a dramatic impact of pregnancy. More information on specific patterns of prescription needs to be gained in order to establish decision-making models for psychotropic prescription during pregnancy., (© 2014 Société Française de Pharmacologie et de Thérapeutique.)

The participants in round table 6 of the Giens Workshops 2012 drafted recommendations based on the collective interpretation of important elements of the decree concerning the medico-economic evaluation of health products published a few days earlier (02 October 2012). The medico-economic evaluation (MEE), becomes an additional determinant for fixing the prices of health products by the Health products economic committee (Comité économique des produits de santé, CEPS) via the hierarchisation of treatment strategies, and thus modifies the market access conditions. Limiting the analysis to medicinal products and medical devices for which a major, important or moderate improvement in the medical service rendered (ASMR) or of the expected service (ASA) has been requested and presenting a significant budget impact on the Social Security expenses, excludes health products with ASMR or ASA with a lower level requested which often create complex price fixing problems and often have a major budget impact. This latter concept remains to be defined in detail. The MEE envisaged for the first registration must include the need to confirm or refute the initial hypotheses especially concerning the actual position in the therapeutic strategy at the time of renewal of the registration. For the first registration, the conventional reference to European prices guaranteeing a minimum price to innovative medicinal products, the medico-economic models submitted by the industry to the French Drug Authority (Haute autorité de santé, HAS) must be used to guide the compilation of new data to be requested at the time of the registration renewal and to negotiate the level of the discounts in the framework of a price-volume agreement, if applicable. The MEE will allow comparing the result of the analysis to the model hypothesis at the time of the renewal of the registration, which may contribute to the renegotiation (either up or down) of the price of health goods. The costs related to obtaining new data must be controlled. In order for the MEE to allow confirming the relationship between the price requested and the benefit expected, the group privileges the definition of reference values with an indicative and non-normative value, likely to evolve with time rather than a threshold. Concerning the evaluation procedure: the time to market access must not be lengthened; while the possibility of regular meetings between the industry and the HAS is recommended to avoid methodological divergences. A transitory period should allow the implementation of the entire evaluation procedure which must also take into account the specificities of health products registered before the 3 October 2013., (© 2013 Société Française de Pharmacologie et de Thérapeutique.)

The primary objective of the S.AGES cohort is to describe the real-life therapeutic care of elderly patients. Patients and methods. This is a prospective observational cohort study of 3 700 non-institutionalized patients over the age of 65 years with either type 2 diabetes mellitus (T2DM), chronic pain or atrial fibrillation (AF) recruited by French general practitioners (GPs). Follow-up is planned for 3 years. Baseline characteristics. In the chronic pain sub-cohort, 33% of patients are treated with only grade 1 analgesics, 29% with grade 2 analgesics and 3% with grade 3 analgesics, and 22% have no pain treatment. In the T2DM sub-cohort, 61% of patients have well-controlled diabetes (Hb1c<7%) and 18% are treated with insulin. In the AF sub-cohort, 65% of patients have a CHADS2 score greater than 2, 77% are treated with oral anticoagulants, 17% with platelet inhibitors, 40% with antiarrhythmic drugs and 56% with rate slowing medications. Conclusion. The S.AGES cohort presents a unique opportunity to clarify the real-life therapeutic management of ambulatory elderly subjects and will help to identify the factors associated with the occurrence of major clinical events., (© 2013 Société Française de Pharmacologie et de Thérapeutique.)

One of the challenges of the coming years is to personalize medicine in order to provide each patient with an individualized treatment plan. The three objectives of personalized medicine are to refine diagnosis, rationalize treatment and engage patients in a preventive approach. Personalization can be characterized by various descriptors whether related to the field, biology, imaging, type of lesion of the entity to be treated, comorbidity factors, coprescriptions or the environment As part of personalized medicine focused on biological markers including genetics or genomics, the integration of the clinical development plan to obtain marketing authorization may be segmented in 3 stages with a known descriptor identified before clinical development, a known descriptor discovered during clinical development or a known descriptor known after clinical development. For each stage, it is important to clearly define the technical optimization elements, to specify the expectations and objectives, to examine the methodological aspects of each clinical development phase and finally to consider the fast changing regulatory requirements in view of the few registered therapeutics complying with the definition of personalized medicine as well as the significant technological breakthroughs according to the screened and selected biomarkers. These considerations should be integrated in view of the time required for clinical development from early phase to MA, i.e. more than 10 years. Moreover, business models related to the economic environment should be taken into account when deciding whether or not to retain a biomarker allowing the selection of target populations in a general population., (© 2012 Société Française de Pharmacologie et de Thérapeutique.)

Little is known of the influence of nutritional status on cytochrome P450 (CYP) 1A2 activity in elderly patients. Thirty elderly institutionalised patients with malnutrition (group A, aged 88 +/- 5 years) and 24 without (group B, aged 81 +/- 9 years) were included. Malnutrition was defined as weight loss of >10% over the previous 6 months and/or a body mass index (BMI) <21 kg/m2 and albuminaemia < or = 32 g/L. CYP1A2 activity was evaluated by the plasma paraxanthine/caffeine (PAX/CAF) metabolic ratio. The plasma PAX/CAF metabolic ratio was similar in both groups regardless of nutritional status (0.34 +/- 0.13 [A] versus 0.30 +/- 0.11 [B]; p = 0.11). The CYP1A2 metabolic ratio was not correlated to either BMI, serum albumin or renal clearance. CYPI A2 activity, as measured by the plasma PAX/CAF ratio, was not influenced by nutritional status in elderly patients.

The HMG-CoA reductase inhibitors (statins) and fibrates have been associated with myotoxicity, which, in some cases, has been fatal. Rhabdomyolysis is frequently observed during drug interactions with elevated plasma concentrations. Statins have a low oral bioavailability because of their intense first-pass extraction. Cytochrome P450 3A4 (CYP3A4) is responsible for the metabolism of atorvastatin and simvastatin which present the highest risk of drug interactions with CYP3A4 inhibitors, such as macrolides, antifungal agents, protease inhibitors, calcium channel blockers, amiodarone, and grapefruit juice. Fluvastatin has a low potential for drug interactions due to its CYP2C9-dependant metabolism. Pravastatin liver extraction does not involve CYPs and presents a low potential for drug interactions. Fibrates have a high oral bioavailability (approximately 100%), and this minimises the risk of drug interactions. However, fibrates alter the pharmacokinetics of some drugs, possibly via CYP2C9 and UDP-glucuronyltransferase (UGT) inhibition. Only three cholesterol-reducing agents have demonstrated their ability to reduce the incidence of cardiovascular death in long-term follow-up randomised trials among patients with atherosclerosis. Simvastatin exhibits the highest potential for drug interactions, pravastatin and gemfibrozil the lowest.

Liver drug metabolism is a major source of drug interactions. Three major human in vitro models are employed to detect drug interactions in the preclinical phases of drug development: recombinant enzymes, human liver microsomes and primary human hepatocyte cell cultures. Results obtained from these models may vary during the different phases of drug development. Identification of the metabolic pathways, enzymes involved in drug metabolism (mainly cytochrome P450s), enzyme induction or inhibition allow us to detect the major pharmacokinetic drug interactions which can occur in man and to identify specific populations at risk for such interactions. In vitro models are essential to decide if and which future drug interaction studies should be performed in man. However, the clinical relevance of the potential pharmacokinetic drug interactions detected by these in vitro models remains to be determined and confirmed by human studies.

Objectives: To determine the viability and differentiation of human hepatocytes immunoprotected by encapsulation and transplanted in rats without immunosuppression., Methods: Freshly isolated human hepatocytes were encapsulated in hollow fibers and transplanted in the peritoneal cavity of immunocompetent rats. The fibers were explanted for analysis at D3, D7 and D14 following transplantation. Morphological features under light and electron microscopy and gene expression were compared to those of non-transplanted encapsulated hepatocytes (D0). Human cytochrome P450 3A and albumin mRNAs were quantified by Northern blot. Cytochrome P450 3A proteins were detected by Western blot and cytochrome P450 3A enzyme activity was assessed by measuring the formation of 6beta-hydroxytestosterone by high performance liquid chromatography., Results: Transplanted hepatocytes were more than 60 % viable and exhibited morphological criteria of hepatocytic differentiation up to D7. Albumin and cytochrome P450 3A transcripts were also detected up to D14. At D3 and D7, albumin mRNA levels were of 30 %, compared to control D0 hepatocytes, while cytochrome P450 3A5 and cytochrome P450 3A4 mRNA levels were 65 % and 0 %, respectively. Cytochrome P450 3A immunoreactivity was detected by Western blot up to D14 and 6beta-hydroxylase activity was 17 % at D3 compared to D0, supporting with disappearance of cytochrome P450 3A4 mRNA., Conclusions: Human hepatocytes remain viable for a short period, following encapsulation and intraperitoneal transplantation in rat. Other experimental conditions need to be tested to prevent or delay a decrease in hepatocyte specific gene expression.

Between 1968 and 1991, 36 pregnancies were reported in 28 patients who had undergone kidney transplantation at the Necker hospital, Paris. Pregnancies with favourable graft outcome were compared with those accompanied by significant deterioration of graft function and requiring haemolysis. The risk factors for renal function deterioration during pregnancy in kidney-transplanted women were found to be an initial nephropathy induced or aggravated by a previous pregnancy, an alteration, even mild, of graft function, hypertension, even controlled by treatment, an HLA mismatch and several episodes of acute graft rejection soon after kidney transplantation.