Critical reappraisal of vitamin D deficiency

The current surge of interest in vitamin D is fuelled not only by evidence that vitamin D supplementation decreases the risk of osteoporotic fractures but also by vast observational studies indicating a variety of beneficial extraskeletal effects (including decreases in the risks of cancer, inflammatory diseases, and even death). Serum 25-hydroxyvitamin D (25(OH)D) assay is now a highly reliable method for evaluating vitamin D stores in individual patients. Nevertheless, the normal or desirable 25(OH)D range for patients seen in everyday clinical practice needs to be more accurately defined. Maintaining serum 25(OH)D above 75 nmol/L is currently recommended to ensure optimal bone health, but higher levels may be required to obtain some of the extraskeletal benefits. Naturally occurring vitamin D is by far the most widely used form for correcting vitamin D deficiency, and the hydroxylated derivatives have only a few highly specific indications. However, controversy persists about the optimal modalities of natural vitamin D supplementation in terms of the type of vitamin (D2 or D3), schedule (once daily or at wider intervals), and route (oral or injectable). For chronic supplementation to protect against bone loss, a daily dosage of at least 800 IU seems required. Higher dosages (e.g., 100,000 to 200,000 IU every 2 months for 6 months) may be needed to correct established vitamin D deficiency; a repeat 25(OH)D assay after 4 to 6 months may help to assess the treatment response and to adjust the subsequent vitamin D dosage. The current emphasis is on the detection of vitamin D deficiency in the general population and in subgroups at risk for osteoporosis followed by an assessment of severity and the initiation of appropriate treatment. From a public health perspective, supplying at least 800 IU per day seems useful and safe

Physical-chemical stability of docetaxel concentrated solution during one month

Background  Docetaxel is an antineoplastic agent widely used in combination with others cytotoxic agents in many cancers (breast cancer, non-small cell lung cancer, prostate cancer, etc.). Today, this costly cytotoxic agent is marketed by several pharmaceutical companies who suggest discarding any remainder immediately after use, making it a very costly drug. Purpose  The aim of this study was to determine the physical-chemical stability of docetaxel stock solution after the first sampling in the vial. Materials and methods  The study was conducted in accordance with European consensus guidelines for the practical stability of anticancer drugs (1) and by two societies GERPAC and SFPC (2). The physical-chemical stability was assessed on 3 different vials of docetaxel (Taxotere 20 mg/mL). On day 0, 2, 4 and 30 triplicate samples of each vial of docetaxel were assayed by a high performance liquid chromatography (HPLC) method with UV detection at 230 nm (method validated following ICH guidelines). Docetaxel concentration at day 0 was considered to be 100% and if the docetaxel concentrations in samples were greater than 90% in the following days they were considered stable. The reference concentration was degraded by 20% by addition of a quantity of 0.01N NaOH in order to produce and observe primary degradation products. On each vial and on different days, docetaxel UV absorption spectra between 200 and 600 nm, pH and colour change were compared by a visual inspection with reference at T = 0, and finally a turbidimetry method at 350, 410 and 530 nm was used to evaluate the formation of visible and sub-visible particles. Results  After 30 days, for each sample, no colour or pH change were observed, all UV spectra and turbidimetry measures were strictly similar. From day 2 to day 30, docetaxel concentrations were not significantly different to the day 0 solution and no degradation products were observed in any samples. According to these results, no significant drug loss was shown during the study period. Conclusions  At a storage temperature between 20 to 25°C for 30 days, docetaxel solution at 20 mg/mL was seen to be stable. The sterility of the solution was not tested because the handling environment (Iso 5) was strictly controlled and operator validations are regularly checked

New lipid nanocapsules for decitabine encapsulation

Introduction: Currently decitabine, an antimetabolite agent is approved for acute myeloid leukemia in old patients and is administered via intra-venous (IV) route. It is a harsh treatment characterized by side effects mainly related with the IV administration as pain, risk of infectious, nursing and hospitalization. Oral route may represent a valid alternative route to IV administration because patient convenience and compliance. Due to the quick hydrolyze of the molecule in acidic conditions, decitabine oral bioavailability is very low, it ranges from 3.9 to 14%. The objective of this work was to design and develop a novel formulation to administer the decitabine per os. Material and method: Firstly, decitabine was solubilized in a reverse micelle (RM) formulation based on a mixture of Transcutol® HP and Tween® 80. RM were then incorporated into lipid nanocapsules (LNC-RM) (1).The formulation was then freeze dried and the stability after the freeze drying process was evaluated by comparing the size, the polydispersity index and the zeta potential to the initial values obtained before the freeze drying. The drug paylaod and encapsulation efficiency were determined after an ultracentrifugation to collect the free decitabine and the decitabine loaded in LNC-RM in two different fractions. In vitro release behavior of decitabine from LNC-RM in PBS medium (pH 7.4, 37°C) was evaluated using a dialysis method (Float a Lyzer 100kDa) and compared with the free drug solution. The drug was quantified using LC-MS/MS method. Finally, in vitro permeability study of decitabine-loaded LNC-RM was assessed in a Caco-2 cell model (2). Results and discussion: After freeze drying LNC-RM were stables showing an average size of around 30nm, with a low polydispersity index and a neutral zeta potential. The decitabine payload was 216±57µg/mL, with an encapsulation efficiency of 45±8%. The in vitro release results showed that, after 90min, almost 5% of decitabine was released from the LNC-RM, while the 45% was released from decitabine solution. The apparent permeability was increased when decitabine is encapsulated as compared to the free drug solution in the Caco-2 model after a contact of four hours. Conclusion: Here we presented a new formulation for the oral administration of decitabine. Further studies will be developed to assed the stability of the system in simulated gastro-intestinal media. References: (1) Heurtault B., et al. Pharm Research. 19(6), 2002 (2) Roger E., et al. Eur J Pharm Biopharm. 79(1), 201

Design and stability study of a paediatric oral solution of methotrexate 2mg/ml

Oral paediatric forms development by pharmaceutical industry is still insufficient. The present study was performed to propose an adapted and pleasant formulation of liquid oral formulation of MTX. The solution is composed of injectable methotrexate, water, Ora Sweet(®) and sodium bicarbonate. After 120 days storage, pH remained stable at about 8 in all formulations, insuring no risk of MTX precipitation. MTX content in solution formulation, determined by high performance liquid chromatography measurements, remained in the specifications of >90% of the initial concentration when stored at 4 and 25°C. Forced degradation of MTX by heat and acidic conditions allowed formation and detection of degradation products by the analytical method. Microbial study of the preparation shows that the solution remains in the specifications during all the storage, or after one sample each week during one month, eventually indicating the microbial properties are not affected by patient use. To conclude, we here propose a new MTX liquid formulation stable for at least 120 days

Phase mapping of aging process in InN nanostructures: oxygen incorporation and the role of the zincblende phase

Uncapped InN nanostructures undergo a deleterious natural aging process at ambient conditions by oxygen incorporation. The phases involved in this process and their localization is mapped by Transmission Electron Microscopy (TEM) related techniques. The parent wurtzite InN (InN-w) phase disappears from the surface and gradually forms a highly textured cubic layer that completely wraps up a InN-w nucleus which still remains from original single-crystalline quantum dots. The good reticular relationships between the different crystals generate low misfit strains and explain the apparent easiness for phase transformations at room temperature and pressure conditions, but also disable the classical methods to identify phases and grains from TEM images. The application of the geometrical phase algorithm in order to form numerical moire mappings, and RGB multilayered image reconstructions allows to discern among the different phases and grains formed inside these nanostructures. Samples aged for shorter times reveal the presence of metastable InN:O zincblende (zb) volumes, which acts as the intermediate phase between the initial InN-w and the most stable cubic In2O3 end phase. These cubic phases are highly twinned with a proportion of 50:50 between both orientations. We suggest that the existence of the intermediate InN:O-zb phase should be seriously considered to understand the reason of the widely scattered reported fundamental properties of thought to be InN-w, as its bandgap or superconductivity.Comment: 18 pages 7 figure

Développement et validation d’une méthode de dosage des traces de détergents inactivants totaux du prion

OBJECTIVES: In this study, a novel analytical method to quantify prion inactivating detergent in rinsing waters coming from the washer-disinfector of a hospital sterilization unit has been developed. The final aim was to obtain an easy and functional method in a routine hospital process which does not need the cleaning product manufacturer services. METHODS: An ICP-MS method based on the potassium dosage of the washer-disinfector\u27s rinsing waters was developed. Potassium hydroxide is present on the composition of the three prion inactivating detergent currently on the French market. The detergent used in this study was the Actanios LDI(®) (Anios laboratories). A Passing and Bablok regression compares concentrations measured with this developed method and with the HPLC-UV manufacturer method. RESULTS: According to results obtained, the developed method is easy to use in a routine hospital process. The Passing and Bablok regression showed that there is no statistical difference between the two analytical methods during the second rinsing step. Besides, both methods were linear on the third rinsing step, with a 1.5ppm difference between the concentrations measured for each method. CONCLUSIONS: This study shows that the ICP-MS method developed is nonspecific for the detergent, but specific for the potassium element which is present in all prion inactivating detergent currently on the French market. This method should be functional for all the prion inactivating detergent containing potassium, if the sensibility of the method is sufficient when the potassium concentration is very low in the prion inactivating detergent formulation

Decitabine encapsulation in nanovector to improve acute myeloid leukemia treatment

Acute myeloid leukemia (AML) mainly affects adult patients, and for older ones unfit for intensive chemotherapy only few therapies are available. Hypomethylating agents, as decitabine, is a labeled option but its plasma half-life is short whereas a long cell exposure time improves response rate. Only intravenous administration is available, whereas an oral route is generally preferred by patients. Consequently, to enhance plasma half-life and to develop an oral decitabine formulation, in this work decitabine was encapsulated in nanoparticles. Two different strategies were tested: decitabine loaded into lipid nanocapsules (DAC-LNC), and a decitabine-prodrug synthesis [3’(OH)-5’(OH)-(lauroyl)2-modified DAC] encapsulated into LNC (DAC-(C12)2-LNC). DAC-LNC and DAC-(C12)2-LNC particles were obtained with sizes of 26.5 ± 0.5 nm and 27.45 ± 0.05 nm respectively, and drug payloads of 0.47 ± 0.06 mg/mL and 5.8 ± 0.5 mg/mL (corresponding to 2.3 ± 0.2 mg/mL of decitabine). Both formulations were able to increase in vitro human plasma half-life by protecting decitabine from degradations. Compared to free-decitabine solutions, both nanoparticle formulations were able to preserve decitabine cytotoxicity on an AML cell line (HEL). Moreover, permeability studies across an adenocarcinoma cell model (Caco-2 cells) demonstrated that DAC-LNC improve decitabine’s intestinal permeability whereas DAC-(C12)2-LNC decreased it. However, this drawback could be countered by the enhanced decitabine’s stability in gastrointestinal fluids thanks to DAC-(C12)2-LNC, leading to more available drug for absorption. Globally, both formulation have demonstrated their ability to improve DAC plasma half-life in vitro and their potential for oral administration. In vivo pharmacokinetics evaluations may now confirm interests of such strategies

Development of decitabine nano objects for oral administration

Introduction: Currently decitabine (trade name Dacogen®) is only approved for acute myeloid leukemia in old patients and is administered via intra-venous (IV) route once a day for five days, every four weeks. It’s a painful treatment with difficulties due to IV administration: pain, risk of infectious, nursing, hospitalization. Decitabine oral bioavailability is limited to 3.9 to 14% mainly due to the quick hydrolyse of the molecule in acidic conditions. The aim of our study was to design new formulations to administer decitabine orally. Material and methods: Four different nano-object strategies, already published, have been adapted for decitabine encapsulation: lipid nanocapsules (LNC) with a Transcutol® HP core (1), lipid drug conjugate (LDC) (2), polymeric nanoparticles (NP) (3), and LNC loaded with reverse micelles (LNC-RM) (4). For each strategy, size, polydispersity index (PdI), and Zeta potential were monitored by dynamic light scattering on a Zetasizer® Nano series DTS 1060. Encapsulation efficiency and encapsulation yield were determined after an ultra-centrifugation of the formulation or by filtration associated to centrifugation depending on the nanoparticles formulated. An UPLC-UV method was developed to quantify decitabine. Results and discussion: Very different sizes of nanoparticles were obtained: 27.4±1.6 nm for LNC-RM, 38.7±7.0 nm for LNC, 34.3±4.5 nm for LDC and 145.2±0.9 for NP. PdI were found inferior to 0.2 for all the encapsulation strategies used. Encapsulation efficiency was not sufficient for LNC, LDC and NP (1.20±2.00%, 25.00±1.94% and 2.81±3.10% respectively) but promising for the LNC-RM (48.76±14.18%), corresponding to an encapsulation yield of 244.6±74.9μg/mL. Conclusion: All formulations were prepared with only GRAS excipients and without class 1 and 2 solvents. Analytical method were designed and validated in accordance with the international conference on harmonization. An interesting formulation based on LNC and reverse micelle were obtained. The stability of this formulation in simulated fluids and in vitro permeability across a caco-2 cells culture model are in progress. References: (1) Heurtault B., Saulnier P., Pech B., Proust J-E., B J-P. Pharmaceutical Research. 19(6), 875-880, 2002 (2) Neupane Y-R., Sabir M-D., Ahmad N., Ali M., Kohli K. Nanotechnology. 24, 1-11, 2013 (3) Gonzalo T., Lollo G., Garcia-Fuentes M., Torres D., Correa J., Riguera R., Fernandez-Megia E., Calvo P., Avilés P, Guillén M-J., Alonso M-J., Journal of Controlled Release. 169, 10–16, 2013 (4) Vrignaud S, Anton N, Gayet P, Benoit J-P., Saulnier P. European journal of pharmaceutics and biopharmaceutics. 79, 197-204, 201

Stability of micafungin sodium solutions at different concentrations in glass bottles and syringes

Micafungin is a costly treatment and packaging of 50mg or 100mg bottles only are available, while doses lower than 5mg and 20mg are often necessary in neonates and paediatrics patients, respectively. The stability of micafungin sodium in polypropylene syringes and glass bottles was studied at different concentrations. Solutions of micafungin diluted with NaCl 0.9% were prepared in glass bottles (20 and 10mg/mL) or syringes (1 and 0.5mg/mL) and stored at 25°C, 60% humidity (RH), in the dark (ICH conditions). Solutions were also exposed to heat (70°C) or alkaline solution (NaOH) in order to force degradation. Samples were analysed at days 1, 5, 8 (for bottles) and also 15 (for syringes) after the preparation and assayed in triplicate. Stability was studied using a stability-indicating high-performance liquid chromatographic method. Syringes stored at 25°C retained over 90% of their initial concentration over the study period. Temperature and alkaline conditions had significant effect on the stability of micafungin, leading to apparition of degradation products. Moreover, sub visible particles were in the specification of the European Pharmacopeia along 15 days. To conclude, micafungin diluted in NaCl 0.9% and stored in polypropylene syringes was chemically stable for at least 15 days at 25°C in the dark