Towards harmonization of solutions used for cystic fibrosis diagnosis by nasal potential difference measurements: A formulation approach with CHESS® software.

BACKGROUND: One diagnosis of cystic fibrosis involves measuring the nasal transepithelial potential difference (NPD) as a complementary technique in the forms of the disease, where the sweat test is non-discriminating. The NPD is measured using solutions with and without chlorides, containing a variety of substances whose activities on nasal mucus membranes are studied or assessed. Among the solutions described in the literature and used in specialized centers, none seems to be best adapted for industrial production for reasons of stability (formulas of the international consensus of Rowe et al. and formulas of Knowles et al.) and/or potential toxicity (formulas of Middleton et al.). OBJECTIVE(S): Defining new formulas, according to those of the international consensus, with greater physicochemical and microbiological stability. METHODS: The reformulation tests were conducted on the formulas of Rowe et al., using CHESS® (CHemical Equilibrium of Species and Surfaces) software for modeling aqueous systems that substantially reduced the number of experiments. CHESS® software was first validated using models of ideal and non-ideal solutions. Thereafter, experimentation was carried out for the sake of comparison with theoretical data. RESULTS: CHESS® software using models of ideal and non-ideal solutions were validated. The experimentation confirmed the theoretical data, and new formulas were assessed based on their physicochemical (pH, content, Osmolality) and microbiological stability. CONCLUSION: The new formulas defined here guarantee excellent physicochemical and microbiological stability of diagnostic solutions, indispensable criteria for harmonizing and comparing results from different specialized centers using NPD measurements. These new formulas apply to the harmonization approach of techniques for measuring the nasal transepithelial potential difference.

Interest of flow injection spectrophotometry as an orthogonal method for analyzing biomolecule aggregates: Application to stressed monoclonal antibody study.

This study aimed to explore the suitability of flow injection spectrophotometry (FIS) to analyze three degraded therapeutic monoclonal antibodies (bevacizumab, nivolumab, and rituximab). For this purpose, aggregates were generated with stirring, freeze-thaw, and heat stresses. The intact and stressed mab samples were filtered with 0.22 µm hydrophilic filters and analyzed by size exclusion chromatography (SEC), cation-exchange chromatography (CEX), and FIS. In terms of quantitative and qualitative analysis, protein loss and structural changes were assessed. Various aggregates profiles were obtained according to the mabs and the stresses. FIS allowed performing very satisfactory quantifications for each mab with intermediate precision RSD < 3.0 % and recovery between 97.9 and 102.0 %. From the protein loss measurements, it appears that SEC underestimates the mab aggregate proportions up to two times less as compared with FIS since the latter avoids any non-specific interactions (electrostatic or hydrophobic interactions). Using second derivative spectroscopy and multivariate data analysis, we noticed apparent structural differences, located in the regions 245-265 nm for rituximab and nivolumab and 280-300 nm for bevacizumab, depending on the stress. The FIS complementarity with the other techniques used in this study allowed us to demonstrate that the three mabs behave differently for a given stress condition. While extreme mechanical stress formed large aggregates irrespective of the mabs, rituximab showed to be less stable and more sensitive than the two other mabs under freeze-thaw and heat stresses, generating large aggregates (>200 nm) and partial unfolding. Nivolumab tends to form small aggregates less than 50 nm when heated and freeze-thawed. Moreover, freeze-thaw seems to generate native IgG-1 aggregates with rituximab. Similarly, bevacizumab showed to form these IgG-1 aggregates and was resistant to freeze-thaw, likely thanks to trehalose cryoprotectant from its formulation. Finally, FIS associated with multivariate analysis can provide rich information in one single run and appears to be a fast, simple, and reliable method to set complementary and orthogonal approaches for protein aggregates monitoring.

[Health technology assessment of innovative medical devices: Timing and decision at national and local level]. / Accès au marché des dispositifs médicaux innovants : articulation entre évaluations nationales et hospitalières.

INTRODUCTION: The Medical Device Committee (CODIMS) evaluates all innovative medical devices (MD) before their introduction in the hospitals of the Assistance publique-hôpitaux de Paris (AP-HP). At the national level, the Medical Device and Health Technology Evaluation Committee (CNEDiMTS) provides recommendation for MD with respects to reimbursement by the National Health Insurance Fund. The aim of this study is to compare the recommendations of both committees and to analyze their timing on a six-year period. MATERIAL AND METHOD: We selected all innovative MD assessed by the CODIMS between 2013 and 2018. We retrieved all the recommendations for these MD from the CNEDiMTS. We performed quantitative and qualitative analysis of data collected. RESULTS: On 30 innovative MD assessed by both the CODIMS and the CNEDiMTS, 11 (37%) evaluations were performed by the CODIMS before the CNEDiMTS evaluation. They occurred approximately a year before the CNEDiMTS recommendation (an average of 378 days). Among the 25 MD with a recommendation of both committees, the two opinions were consistent in 88 per cent of all cases. DISCUSSION/CONCLUSION: This study highlights that there is a good consistency between the recommendations of both committees. This suggests that the MD evaluations conducted at the hospital level are relevant and timely. Finally, a better coordination between the national and local levels should be promoted for the MD assessment.

UV spectroscopy and least square matching for high throughput discrimination of taxanes in commercial formulations and compounded bags.

The need for high-throughput quality control of pharmaceuticals after compounding is often required before the treatment of the patients. Ultra-fast analysis using flow injection analysis coupled to UV spectroscopy and least square matching was assessed for the simultaneous quantification and identification of three therapeutic taxanes after dilution in physiological saline (cabazitaxel, docetaxel, and paclitaxel). In-depth preliminary analysis of the zero and first order UV spectra of the taxanes using principal component analysis (PCA) allowed us focusing on relevant spectral range with very low formulation influence. Least square-matching algorithm available on basic HPLC software was applied to these spectra yielding very high match scores (>999) with significant difference (P < 0.0001). The approach was qualitatively assessed through specificity and sensitivity which were excellent for the three taxanes (100%, n = 378), irrespective of their formulation. In terms of quantification, satisfactory linearity and accuracy were achieved for each of the taxanes according to their therapeutic range (0.05 to 1.02 mg·mL-1). The RSD (%) of the precision was satisfactory (<3%). Finally, the suitability of the approach for the taxanes QC has been demonstrated under routine application.

Simple and ultra-fast recognition and quantitation of compounded monoclonal antibodies: Application to flow injection analysis combined to UV spectroscopy and matching method.

Compounding of monoclonal antibody (mAbs) constantly increases in hospital. Quality control (QC) of the compounded mAbs based on quantification and identification is required to prevent potential errors and fast method is needed to manage outpatient chemotherapy administration. A simple and ultra-fast (less than 30 s) method using flow injection analysis associated to least square matching method issued from the analyzer software was performed and evaluated for the routine hospital QC of three compounded mAbs: bevacizumab, infliximab and rituximab. The method was evaluated through qualitative and quantitative parameters. Preliminary analysis of the UV absorption and second derivative spectra of the mAbs allowed us to adapt analytical conditions according to the therapeutic range of the mAbs. In terms of quantitative QC, linearity, accuracy and precision were assessed as specified in ICH guidelines. Very satisfactory recovery was achieved and the RSD (%) of the intermediate precision were less than 1.1%. Qualitative analytical parameters were also evaluated in terms of specificity, sensitivity and global precision through a matrix of confusion. Results showed to be concentration and mAbs dependant and excellent (100%) specificity and sensitivity were reached within specific concentration range. Finally, routine application on "real life" samples (n = 209) from different batch of the three mAbs complied with the specifications of the quality control i.e. excellent identification (100%) and ±â€¯15% of targeting concentration belonging to the calibration range. The successful use of the combination of second derivative spectroscopy and partial least square matching method demonstrated the interest of FIA for the ultra-fast QC of mAbs after compounding using matching method.

[3D printed medical devices and anatomical models: What kind of distribution and which uses in French hospitals?] / Dispositifs médicaux et modèles anatomiques produits par impression 3D : quelle diffusion et quelles utilisations dans les établissements de santé français ?

3D printing plays an increasingly important role in the medical sector and particularly in surgery. Nowadays, numerous manufacturers benefit from this technology to produce their medical devices and some hospitals have also purchased 3D printers. In this context, the aim of the present study was to study the distribution and the use of 3D printing in French hospitals in order to its main features in surgery. By conducting a national survey, we targeted hospitals equipped with 3D printers and those using external providers to benefit from this technology. Forty-seven hospitals were identified as using 3D printing including eight equipped with in-house 3D printers. This work gives us a first picture of 3D printing for hospital use in France and it raises questions about hospital pharmacists' involvement in 3D printed medical device production.

Discrimination and quantification of two isomeric antineoplastic drugs by rapid and non-invasive analytical control using a handheld Raman spectrometer.

Raman spectroscopy is a rapid, non-destructive and non-invasive method that is a promising tool for real-time analytical control of drug concentrations. This study evaluated a handheld Raman device to discriminate and quantify two isomeric drugs used to treat cancer. Doxorubicin (DOXO) and epirubicin (EPIR) samples were analyzed at therapeutic concentrations from 0.1 to 2mg/mL (n=90) and 0.08-2mg/mL (n=90) by non-invasive measurements using a portable Raman spectrometer. The discrimination of these two molecules was demonstrated for all concentrations (n=180) by qualitative analysis using partial least square discriminant analysis (PLS-DA) with 100% classification accuracy, sensitivity and specificity and 0% error rate. For each molecule, quantitative analyses were performed using PLS regression. The validity of the model was evaluated using root mean square error of cross validation (RMSECV) and prediction (RMSEP) that furnished 0.05 and 0.02mg/mL for DOXO and 0.17 and 0.16mg/mL for EPIR after pretreatment optimization. Based on the accuracy profile, the linearity range was from 1.256 to 2.000mg/mL for DOXO (R2=0.9988) and from 0.553 to 2.000mg/Ml for EPIR (R2=0.9240) and repeatability (CV% max of 1.8% for DOXO and 3.2% for EPIR) and intermediate precision (CV% max of 2.8% for DOXO and 4.5% for EPIR) were both acceptable. Despite the narrow validated concentration range for quantitative analysis, this study shows the potential of a handheld Raman spectrometer coupled to chemometric approaches for real-time quantification of cytotoxic drugs, as well for discriminating between two drugs with similar UV absorption profiles. Finally, the use of a handheld spectrometer with the possibility of a direct measurement of substances in containers is a potentially valuable tool for combining patient safety with security of healthcare workers.

Medicinal leech therapy and Aeromonas spp. infection.

While the use of medicinal leech therapy (MLT) in reconstructive and orthopaedic surgery is widely described, post-operative complications related to leeches remain a major concern. Aeromonas spp. strains are involved in the majority of reported cases. As surgical success rate is directly impacted, an adapted antibiotic prophylaxis should be instituted in order to minimize these complications. We assessed pharmaceutical process, microbiological control and related infections in order to provide data and choose the appropriate antibiotherapy for patients requiring MLT. We report a clinical and microbiological study over a 24-month period. Clinical data were collected from patients' database, and microbiological analysis both on leeches' tank water and crushed leeches were performed to characterize isolated strains and their susceptibility to antibiotics. A total of 595 leeches were used to treat 28 patients (12 in plastic surgery and 16 in orthopaedic surgery), and three documented cases of post-operative infections were reported. Aeromonas spp. isolates yielded from 62 % of analyzed batches (75 % of Aeromonas veronii). Eighteen Aeromonas spp. isolates yielded from 23 water samples and three crushed leeches. Isolates were similar in tank and crushed leeches. Strains were susceptible to fluoroquinolones, sulfamethoxazole/trimethoprim, aminosides, and third-generation cephalosporins but resistant to amoxicillin/clavulanic acid and second-generation cephalosporins. According to collected data, routine tank water microbiological analyses are mandatory in order to identify leeches' batches containing resistant strains and to discard them. In this context, the surgeon is able to select an appropriated antibiotic prophylaxis in order to avoid MLT associated serious post-operative complications.

[Hospital-based health technology assessment in France: how to proceed to evaluate innovative medical devices?]. / Évaluation des technologies de santé en milieu hospitalier : quelle organisation pour évaluer et acquérir des dispositifs médicaux innovants ?

Innovative medical devices offer solutions to medical problems and greatly improve patients' outcomes. Like National Health Technology Assessment (HTA) agencies, hospitals face numerous requests for innovative and costly medical devices. To help local decision-makers, different approaches of hospital-based HTA (HB-HTA) have been adopted worldwide. The objective of the present paper is to explore HB-HTA models for adopting innovative medical devices in France and elsewhere. Four different models have been conceptualized: "ambassador" model, "mini-HTA" model, "HTA unit" model and "internal committee". Apparently, "HTA unit" and "internal committee" (or a mixture of both models) are the prevailing HB-HTA models in France. Nevertheless, some weaknesses of these models have been pointed out in previous works. Only few examples involving hospital pharmacists have been found abroad, except in France and in Italy. Finally, the harmonization of the assessment of innovative medical devices in France needs a better understanding of HB-HTA practices.

[Computerized prescription for medical devices: examples, interest and limits]. / Vers la prescription informatisée des dispositifs médicaux : exemples d'application, intérêts et limites.

INTRODUCTION: Related to the good practice contract implemented in hospitals, the prescription dedicated to medical devices, such as pharmaceuticals, could promote safety and good practice. MATERIAL AND METHOD: We attempted to implement a computerized prescription for medical devices. In order to illustrate the method, two examples were selected: the Negative Pressure Wound Therapy (NPWT) and the Drug Eluting Stents (DES). RESULTS: In partnership with the medical teams was elaborated a computerized protocol which included all the needed items for the good use of NPWT. For DES, a pre-existing questionnaire was used. We updated it in order to integrate new items such as the prescriber's name, the patient's name, the characteristics of the wound, the DES references and the indications. DISCUSSION AND CONCLUSION: Computerized prescriptions for high-risk and expensive medical devices seem to be an interesting approach to guarantee the patient care safety and to reduce the budget impacts. In order to monitor the indications funded as fee-for-service medical devices, a prescription will emerge as a gold standard in the future in France. Eventually, this study highlights a new activity of clinical pharmacy for hospital pharmacists dealing with medical devices.

Identification of hematite particles in sealed glass containers for pharmaceutical uses by Raman microspectroscopy.

Raman microspectroscopy has been shown to enable the identification of micro-particles inside sealed glass containers for pharmaceutical use without any sample preparation. Raman spectra were collected from unknown particles with a maximum size of 1mm, adsorbed on the inner surface of ampoules. The particles were clearly identified as primarily hematite with traces of magnetite by their characteristic Raman spectral bands. The presence of this deposit was attributed to the projection of iron oxides during the manufacturing process. These oxide particles were not detected by the quality control process of the glass manufacturer, showing that in-process quality controls failed to detect this problem. Particle identification by Raman microspectroscopy appears to be a selective, rapid and reliable analytical procedure for quality control and assurance in the pharmaceutical industry. Identification of the particles was also helpful for evaluating the nature of the contaminant and enables consequences for the toxicological aspects of final product quality to be managed.

[Quality insurance system establishment in the management of home-based chemotherapy: example of hospital at home "Assistance publique-Hôpitaux de Paris"]. / Mise en place d'un système d'assurance-qualité dans la prise en charge des chimiothérapies à domicile : exemple de l'hospitalisation à domicile « Assistance publique-Hôpitaux de Paris ¼

While home-based chemotherapy improves comfort and quality of life of patients, quality and safety conditions must be equivalent to hospital settings. In addition, organization is much more complex. At the hospital at home "Assistance publique-Hôpitaux de Paris", prescribers are potentially spread across 21 health facilities. The administration of chemotherapy is performed by about 300 nurses at the patient's home in Paris and its suburbs. Centralized preparations of chemotherapy began in September 2009 by the pharmacy department of Georges-Pompidou European hospital, with a progressive increase of the activity. This article describes the quality insurance system established with this new organization to meet the specific challenges of home therapy: choice of eligible anticancer drugs, computerized information systems and networking with other heath facilities, secure transport conditions, traceability from the prescription to the administration, security of administration. This experience can offer an important support for other centres in their approach of quality insurance for home chemotherapy.

Non-adherence with drug treatment after heart or lung transplantation in adults: a systematic review.

OBJECTIVE: Heart or lung transplantation is a complex intervention requiring medication adherence. The objective of this systematic review is to estimate the prevalence of non-adherence (NA) with post-transplantation medication in heart or lung recipients and to assess its clinical impact. We examined in the selected studies if the authors considered the patient's perspective in their evaluations. METHODS: The electronic database MEDLINE, EMBASE and The Cochrane Central Register were searched. Only studies that reported the number of non-adhere subjects were eligible. The different methods of measurement, the ways in which authors defined NA and if authors had integrated patient's perspective in their secondary objectives were also assessed. RESULTS: The range frequency of NA was 1-42.9% for all drugs. Non-adherent patients tend to experience worse outcomes compared to adherent patients. The patient's perception of drug side-effects is the most reported patient-related factor for impairing adherence. CONCLUSION: NA after heart or lung transplantation is an important issue and concerns not only immunosuppressant treatments. The main striking point of the selected studies is the lack of patient perspective and the omission of patients-healthcare providers' relationship. PRACTICE IMPLICATIONS: Future research must focus on patients' motivation for the medication-taking behaviour.

Clinical outcomes of lung-transplant recipients treated by voriconazole and caspofungin combination in aspergillosis.

BACKGROUND AND OBJECTIVE: Invasive pulmonary aspergillosis (IPA) is a serious cause of death among immune-compromised patients such as organ-transplant recipients. Recently, voriconazole has been approved for first-line therapy in IPA. Theoretically, optimal voriconazole blood level (superior to 1 mg/L according to recent studies) should be reached within 24 h. In practice, a significantly longer time seems to be needed in lung-transplant recipients. Therefore, caspofungin is now used in combination with voriconazole to provide cover against Aspergillus spp. infection during this gap. The first aim of this study was to investigate Aspergillus spp. infection treated with this combination and the atter's tolerability. The median time for attainment of apparently active blood levels in lung transplant recipients were compared between those with cystic fibrosis and those without. METHODS: Lung-transplant recipients who received a combination of voriconazole and caspofungin between 2002 and 2008 as primary therapy were identified retrospectively. The median number of days to reach active voriconazole blood levels was compared between cystic fibrosis and other patients by Student's t-test. Statistical significance was defined by P-value <0.05. RESULTS: Four patients were treated for Aspergillus colonization before transplantation and their culture were negative at 90 days. Eleven patients were treated for proven or probable invasive aspergillosis and 14 of them had a complete response. Hallucinations (n = 2) and significant hepatic toxicity (n = 2) were reported. Among the 15 studied transplant recipients, a median of 12.3 days was observed for active voriconazole blood levels to be reached. With cystic fibrosis patients, time tended to be longer than with other recipients (14.9 days vs. 8.3 days). Tacrolimus blood levels (between 5 and 15 ng/mL) may have been increased by voriconazole. CONCLUSION: This retrospective study describes practical experience in the management of this rare and severe disease in a referral centre for cystic fibrosis lung transplantation. Voriconazole and caspofungin combination was acceptably safe and was associated with good clinical outcomes in almost all patients. We showed that in 15 lung-transplant recipients a median of 12.3 days was required for voriconazole to reach high enough blood levels. Caspofungin in combination with voriconazole provides cover against Aspergillus infection during the period when voriconazole may be at subtherapeutic levels with good tolerability.

[Fabry disease: enzymatic screening using dried blood spots on filter paper]. / Dépistage de la maladie de Fabry par mesure de l'activité enzymatique de gouttes de sang séché sur papier filtre.

INTRODUCTION: Fabry disease (FD) is an X-linked lysosomal storage disorder caused by mutations in the GLA gene, which leads to a deficient activity of α-galactosidase A. α-galactosidase A activity can be assayed on dried blood spots on filter paper but the original method has been associated with a number of false positive due in great part to quenching of fluorescence. Here, we describe an adaptation of the original fluorimetric method reducing quenching of the fluorescence. RESULTS: A simple and sensitive fluorimetric method has been described for the determination of the α-galactosidase A activity in dried blood spots on filter paper, convenient for screening of FD in at-risk populations. The procedure uses 4-methylumbelliferyl-α-D-galactose, as a synthetic substrate for the enzyme. In this study, protein precipitation was added after incubation both to stop the enzymatic reaction and eliminate interfering proteins. With the novel method the risk of false-positive due to fluorescence quenching was minimized. A cut-off level of 2.1 µmol.h(-1).L(-1) (control values: 5.6 ± 2.0 µmol.h(-1).L(-1), mean ± SD) was chosen corresponding to 40 % of median control value. In all 60 hemizygotes males, α-gal A activities were below 1.1 µmol.h(-1).L(-1) (0.11 ± 0.2 µmol.h(-1).L(-1)). In the 68 heterozygous females, α-gal A activity ranged from 0 to 7.8 µmol.h(-1).L(-1) (2.2 ± 1.7 µmol.h(-1).L(-1)). Using the improved methodology, one third of the females were not identified using the enzymatic assay, due to significant residual enzyme activity. CONCLUSION: This improved method for the assay of α-gal A was robust and reduced the number of false-positive results. It can be applied for the screening of at-risk populations. α-galactosidase A enzymatic assay should not be used for screening for FD in women or, if used, should be interpreted cautiously together with the results of genotyping.

[Clinical and economical evaluation of bivalirudin during percutaneous coronary interventions]. / Evaluations clinique et économique de la bivalirudine au cours des procédures d'angioplasties coronaires.

Bivalirudin, with provisional GP IIb/IIIa inhibitor use allows the same protection against ischemic complications while reducing the hemorrhagic complications compared with the systematic association of a GP IIb/IIIa inhibitor plus heparin (The Randomized Evaluation in PCI Linking Angiomax to Reduced Clinical Events-2 [Replace-2]). In clinical practice, the use of heparin is not systematically associated with a GP IIb/IIIa inhibitor. That's why we studied the clinical and economic interest of bivalirudin only versus heparin (UFH) only. Opened pragmatic monocentric study carried out in 2007. We made a chronological matching: for each patient treated with bivalirudin, we included the next patient with the same clinical presentation treated with unfractionated heparin. Ninety-two patients were included (46 in each group). The need for a GP IIb/IIIa inhibitor during the PCI was not significantly different between the two groups (p=0.11). No major hemorrhagic complications were observed in the two groups. Prevalence of ecchymosis was not significantly different: 22 % in the UFH group versus 13 % in the bivalirudin group (p=0.27). The average troponin level the next day was significantly higher in the bivalirudin group (p=0,049), although the change in troponin levels before and after the procedure was similar in the two groups. The average cost by patient of anticoagulation by bivalirudin and HNF is very different, respectively 473+/-150 and 51+/-146 euro (p=0.0001). Bivalirudin can be an interesting alternative for patients with a high risk of having complications. But considering its cost this therapy must be used only for selected patients.

[Evaluation of flow rate regulators for intravenous infusion]. / Evaluation des régulateurs de débit passifs utilisés pour la perfusion intraveineuse.

OBJECTIVE: The aim of our study is to evaluate seven flow rate regulators (FRR) to assess the reliability of these devices compared to standard perfuser with roller clamp. STUDY DESIGN: Each FRR was tested with 5% dextrose and 0.9% sodium chloride combined with three different theoretical flow rates (30, 80 and 250 ml/h). Accuracy was compared with the theoretical value. Repeatability of flow rate was assessed thanks to variance break-up. RESULTS: Each FFR exhibits at least one combination "flow rate-solution" significantly different of the theoretical flow rate. Exadrop was the least successful of the FFR according to the accuracy. This FFR had for each combination a flow rate different of the theoretical (mean error: -24.0 ml/h). Tutodrop was the most successful of the FFR according to the accuracy with five combinations comparable to the theoretical value (mean error: -1.2 ml/h). The standard perfuser with roller clamp, used without FRR, reported two combinations comparable to the theoretical value and showed lowest rates for repeatability. CONCLUSION: Our study exhibits the poor performances of the FRR studied: according to expected flow regulation, the reported results demonstrate the lack of accuracy. Their only one value added compare to the roller clamp is to improve the repeatability of the flow rate.

Long-term effects of a multifaceted intervention to encourage the choice of the oral route for proton pump inhibitors: an interrupted time-series analysis.

PROBLEM: Drugs are often given intravenously even when the patient is able to swallow and when an oral form would be more cost-effective. DESIGN: Evaluation of the impact of a multifaceted intervention on the early switch from intravenous to oral administration of proton pump inhibitors (PPI) in a hospital setting. The interrupted time series of intravenous PPI consumption was analysed. BACKGROUND AND SETTING: At a French University Hospital, the Drug Committee, composed of multidisciplinary pharmacy and medical staff, addressed the issue of increasing consumption of intravenous PPI drugs (May 2003). STRATEGY FOR CHANGE: Letters to department heads, academic analyses from members of the Drug Committee, paper reminders at the point of care and audit-feedbacks by pharmacists. Monitoring of consumption and repeated reminder letters were planned. EFFECT OF CHANGE: The consumption of PPI was stable before the first intervention (mean level: 954 units/month). An immediate decrease occurred after the first Drug Committee letter (30% relative reduction, 95% CI -16% to -46%; p<0.001) with a significant trend change during the first multifaceted intervention (-24 units/month, 95% CI -42 to -7; p = 0.007). After the end of the outreach visits (July 2004), the consumptions increased (+32 units/month, 95% CI: 14 to 50, p<0.001). The second intervention had no significant impact. LESSONS LEARNT: A complex intervention (audit, feedbacks, outreach visits) had an effect on practice. It was not sustained even after a less resource-intensive intervention. Other types of interventions are needed that could be continuously implemented to improve ordering practices long term.

[Photosensitizing anticancer tetrapyrroles: or how photophysics becomes a mechanism of action]. / Tétrapyrroles anticancéreux photosensibilisants : ou comment la photophysique devient mécanisme d'action.

The macrocyclic tetrapyrrole derivatives used for the treatment of certain solid tumors include porphyrins and their chlorine and bacteriochlorin derivatives. These are highly conjugated, rigid molecules characterized by a strong absorbance in the spectral domain from near ultra-violet to far red (350-750 nm). The combination of tetrapyrroles plus light is called dynamic phototherapy (DPT). This combination transforms the molecule to its triplet form which by deactivation generates free radicals and a singlet oxygen from molecular oxygen, causing tumor destruction. Tetrapyrroles are thus, with psoralens, used for the treatment of psoriasis. They are the only drugs whose mechanism of action results exclusively from their electronic and photophysical spectroscopic characteristics. This class of anticancer agents is usually free of any specific cytotoxic effect. We describe here the current elements linking structure and spectroscopy and observations leading to the design of compounds with strong tumor selectivity and optimal cytotoxic properties.