Optimization of an in vitro method for assessing pulmonary permeability of inhaled drugs using alveolar epithelial cells.

INTRODUCTION: Inhalation of drugs for the treatment of pulmonary diseases has been used since a long time. Due to lungs' larger absorptive surface area, delivery of drugs to the lungs is the method of choice for different disorders. Here we present the establishment of a comprehensive permeability model using Type II alveolar epithelial cells and Beclomethasone Dipropionate (BDP) as a model drug delivered by pressurized metered dose inhaler (pMDI). METHODS: Using Type II alveolar epithelial cells, the method was standardized for parameters viz., cell density, viability, incubation period and membrane integrity. The delivery and deposition of drug were using the pMDI device with a Twin Stage Impinger (TSI) modified to accommodate cell culture insert having monolayer of cells. The analytical method for simultaneous estimation of BDP and Beclomathasone-17-Monopropionate (17-BMP) was validated as per the bioanalytical guidelines. The extent and rate of absorption of BDP was determined by quantifying the amount of drug permeated and the data represented by calculating its apparent permeability. RESULTS: Type II alveolar epithelial cells cultured at 0.55 × 105 cells/cm2 for 8-12 days under air-liquid interface were optimized for conducting permeability studies. The data obtained for absorptive transport showed a linear increase in the drug permeated against time for both BDP and 17-BMP along with proportional permeability profile. DISCUSSION: We have developed a robust in vitro model to study absorptive rate of drug transport across alveolar layer. Such models would create potential value during formulation development for comparative studies and selection of clinical candidates.

Evaluating the pharmacokinetics of beclometasone dipropionate/formoterol fumarate/glycopyrronium bromide delivered via pressurised metered-dose inhaler using a low global warming potential propellant.

INTRODUCTION: Use of propellants with high global warming potential (such as HFA-134a) for pressurised metered-dose inhalers (pMDIs) is being phased down. Switching to dry-powder inhalers may not be clinically feasible for all patients; an alternative is reformulation using propellants with low global warming potential. The combination of beclometasone dipropionate/formoterol fumarate/glycopyrronium bromide (BDP/FF/GB) is available for asthma or chronic obstructive pulmonary disease via pMDI using HFA-134a as propellant. This is being reformulated using the low global warming potential propellant HFA-152a. This manuscript reports three studies comparing BDP/FF/GB pharmacokinetics delivered via pMDI using HFA-152a vs HFA-134a. METHODS: The studies were four-way crossover, single-dose, randomised, double-blind, in healthy volunteers. In Studies 1 and 2, subjects inhaled four puffs of BDP/FF/GB (Study 1: 100/6/12.5 µg [medium-strength BDP]; Study 2: 200/6/12.5 µg [high-strength]), ingesting activated charcoal in two of the periods (once per propellant). In Study 3, subjects inhaled medium- and high-strength BDP/FF/GB using a spacer. All three studies compared HFA-152a vs HFA-134a in terms of lung availability and total systemic exposure of beclometasone-17-monopropionate (B17MP; active metabolite of BDP), BDP, formoterol and GB. Bioequivalence was concluded if the 90 % confidence intervals (CIs) of the ratios between formulations of the geometric mean maximum plasma concentration (Cmax) and area under the plasma concentration-time curve between time zero and the last quantifiable timepoint (AUC0-t) for the analytes were between 80 and 125 %. RESULTS: In Studies 1 and 2, systemic exposure bioequivalence (i.e., comparisons without charcoal block) was demonstrated, except for GB Cmax in Study 2 (upper 90 % CI 125.11 %). For lung availability (i.e., comparisons with charcoal block), B17MP and formoterol demonstrated bioequivalence in both studies, as did BDP in Study 2; in Study 1, BDP upper CIs were 126.96 % for Cmax and 127.34 % for AUC0-t). In Study 1, GB AUC0-t lower CI was 74.54 %; in Study 2 upper limits were 135.64 % for Cmax and 129.12 % for AUC0-t. In Study 3, the bioequivalence criteria were met for BDP, B17MP and formoterol with both BDP/FF/GB strengths, and were met for GB AUC0-t, although not for Cmax. Both formulations were similarly well tolerated in all three studies. CONCLUSIONS: Overall, while formal bioequivalence cannot be concluded for all analytes, these data suggest therapeutic equivalence of the new formulation with the existing BDP/FF/GB pMDI formulation, therefore supporting reformulation using a propellant with low global warming potential.

Stability-indicating RP-HPLC method for determination of beclomethasone dipropionate in nanocapsule suspensions

abstract A simple stability-indicating RP-HPLC/UV method was validated for determination of beclomethasone dipropionate (BD) in nanocapsule suspensions. Chromatographic conditions consisted of a RP C18column (250 mm x 4.60 mm, 5 µm, 110 Å), using methanol and water (85:15 v/v) as mobile phase at 1.0 mL/min with UV detection at 254 nm. The calibration curve was found to be linear in the concentration range of 5.0-25.0 µg/mL with a correlation coefficient > 0.999. Precision was demonstrated by a relative standard deviation lower than 2.0%. Accuracy was assessed by the recovery test of BD from nanocapsules (98.03% to 100.35%). Specificity showed no interference from the components of nanocapsules or from the degradation products derived from acid, basic and photolytic conditions. In conclusion, the method is suitable to be applied to assay BD in bulk drug and in nanocapsules, and it can be employed to study stability and degradation kinetics.

resumo Um método simples de CLAE-FR/UV indicativo de estabilidade foi validado para a determinação do dipropionato de beclometasona (BD) em suspensões de nanocápsulas. As condições cromatográficas foram: coluna C18 fase reversa (250 mm x 4,60 mm, 5 µm, 110 Å), usando como fase móvel metanol e água (85:15 v/v) a 1,0 mL/min, com detecção UV a 254 nm. A curva de calibração foi linear no intervalo de 5,0-25,0 µg/mL com coeficiente de correlação >0,999. A precisão foi demonstrada por um desvio padrão relativo menor que 2,0%. A exatidão foi avaliada pelo teste de recuperação do BD a partir das nanocápsulas (98,03% a 100,35%). O teste de especificidade não mostrou interferência dos componentes das nanocápsulas e nem dos produtos de degradação derivados de condições ácidas, básicas e fotolíticas. Em conclusão, o método é adequado para ser aplicado na avaliação do BD puro e em nanocápsulas e pode ser empregado para o estudo de estabilidade e degradação cinética.

Formulation and evaluation of CFC free inhalers for beclomethasone dipropionate

Beclomethasone dipropionate CFC free inhalation formulations were developed with a view to treat asthma prophylactically. Dry powder inhalers (DPI) for beclomethasone dipropionate were prepared with different grades of lactose monohydrate. The influence of carrier and overages on performance of DPI was studied. Metered dose inhalers (MDI) with HFA based propellants were formulated with various doses, overages and different concentrations of alcohol. Formulated DPI and MDI were evaluated for various official and unofficial quality control tests. The influence of over doses on valve delivery, effect of overages on emitted dose and influence of alcohol on spray pattern from MDI were studied. The better fine particle fraction and emitted dose were obtained from the DPI formulated with 10:90 ratio of fine lactose: coarse lactose and with 20% w/w overages. The studies on MDI revealed that the 15% of overdoses are required for effective valve delivery and 20% overages are required for 100% drug delivery. 5-10%v/v alcohol was found to be preferable to get optimum emitted dose and fine particle fraction.

Desenvolveram-se formulações por inalação de dipropionato de beclometasona, livres de CFC, com o objetivo de tratar a asma profilaticamente. Prepararam-se inaladores de pó seco (DPI) para o dipropionato de beclometasona com diferentes gradações de lactose monoidratada. Estudou-se a influência do transportador e dos excessos de fármaco em relação ao rotulado no desempenho do DPI. Inaladores de dose calibrada (MDI) com propelentes à base de hidrofluoralcanos (HFA) foram formulados com várias doses, excessos de fármaco em relação ao rotulado e diferentes concentrações de álcool. Avaliaram-se as DPI e MDI formuladas por vários métodos oficiais e não oficiais de controle de qualidade. Estudaram-se a influência da superdosagem na liberação da válvula, o efeito dos excessos na dose emitida e a influência do álcool no padrão do spray do MDI. Obtiveram-se a melhor partícula fina e a dose emitida do DPI formulado com proporção de 10:90 de lactose fina:lactose grossa e 20% p/p de excesso. Os estudos em MDI revelaram que 15% de sobredose são requeridos para a liberação efetiva da válvula e 20% de excessos, para a liberação de 100% dos fármacos. Álcool a 5-10% v/v permitiu alcançar ótima dose emitida e fração de partícula fina.

Estudio comparativo: fenoterol - cromoglicato vs. salbutamol - beclometasona en pacientes pediátricos con asma bronquial moderada / Comparative study: fenoterol - cromoglicate vs salbutamol - beclomethasone in pediatric patients with moderate bronchial asthma

Se evaluó la acción profiláctica de fenoterol-cromoglicato (FC) vs salbutamol-beclometasona (SB) en pacientes pediátricos con asma bronquial moderada. En el primer estudio (estudio A) 60 pacientes fueron distribuidos al azar recibiendo la mitad de ellos FC y la otra mitad SB durante 2 meses, se evaluó índices clínicos y funcionales. Ambos grupos fueron similares al comparar tos, número de crisis, días de ausencia escolar, frecuencia respiratoria, presencia de sibilancias a la auscultación y uso de otros broncodilatadores (p: NS). Ninguno requirió hospitalización. Se encontró diferencia estadísticamente significativa (p<0.01) al analizar VEF y PEF inicial vs VEF y PEF al término del estudio en cada grupo, pero no hubo diferencias significativa al comparar el estudio funcional entre ellos (FC vs SB). En el estudio B, 62 pacientes pediátricos con asma bronquial moderada fueron tratados por 2 meses con SB y luego se distribuyeron al azar continuando 32 de ellos con placebo y 30 con FC por 3 meses más. Tanto la evolución clínica como la respiratoria (VEF y PEF) reveló una evolución favorable al ser tratados con SB. Dicha evolución favorable se continuó en el grupo que recibió FC, no así con el grupo que recibió placebo el cual recayó rapidamente en su sintomatología con un deterioro importante de su función pulmonar. Hubo una diferencia estadísticamente significativa (p< 0.01) a favor de FC vs placebo desde el mes de tratamiento, tanto en las variables clínicas estudiadas como en los índices funcionales. Se evidenció que los pacientes pediátricos con asma bronquial moderada tratados con SB tuvieron una evolución significativamente mejor cuando continuaron su tratamiento con FC que los tratados con placebo (más salbutamol prn) y que incluso se mantuvo la evolución favorable obtenida previamente con SB

Efecto de beclometasona en el eje hipotálamo-hipófisis suprarrenal en niños / Effect of beclomethasone on the hypothalamic-pituitary adrenal axis in children

Se estudió el efecto del dipropionato de beclometasona en 10 niños catalogados como asmáticos con prueba de hiperrectividad bronquial positiva, usando dosis de 400 y 1.000ug/día durante un período de tres meses. Se demostró formación del eje hipotálamo-hipófisis-suprarrenal en dos de los 6 pacientes que recibieron la dosis mayor. No hubo efecto sobre el eje en los pacientes que usaron de 400 ug/día