RESUMEN
A double-blind, dose escalation gene transfer trial was conducted in subjects with cystic fibrosis (CF), among whom placebo (saline) or compacted DNA was superfused onto the inferior turbinate of the right or left nostril. The vector consisted of single molecules of plasmid DNA carrying the cystic fibrosis transmembrane regulator- encoding gene compacted into DNA nanoparticles, using polyethylene glycol-substituted 30-mer lysine peptides. Entry criteria included age greater than 18 years, FEV1 exceeding 50% predicted, and basal nasal potential difference (NPD) isoproterenol responses (> or = -5 mV) that are typical for subjects with classic CF. Twelve subjects were enrolled: 2 in dose level I (DLI) (0.8 mg DNA), 4 in DLII (2.67 mg), and 6 in DLIII (8.0 mg). The primary trial end points were safety and tolerability, and secondary gene transfer end points were assessed. In addition to routine clinical assessments and laboratory tests, subjects were serially evaluated for serum IL-6, complement, and C-reactive protein; nasal washings were taken for cell counts, protein, IL-6, and IL-8; and pulmonary function and hearing tests were performed. No serious adverse events occurred, and no events were attributed to compacted DNA. There was no association of serum or nasal washing inflammatory mediators with administration of compacted DNA. Day 14 vector polymerase chain reaction analysis showed a mean value in DLIII nasal scraping samples of 0.58 copy per cell. Partial to complete NPD isoproterenol responses were observed in eight subjects: one of two in DLI, three of four in DLII, and four of six in DLIII. Corrections persisted for as long as 6 days (1 subject to day 28) after gene transfer. In conclusion, compacted DNA nanoparticles can be safely administered to the nares of CF subjects, with evidence of vector gene transfer and partial NPD correction.
Asunto(s)
Regulador de Conductancia de Transmembrana de Fibrosis Quística/administración & dosificación , Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Fibrosis Quística/tratamiento farmacológico , ADN/genética , Técnicas de Transferencia de Gen , Nanoestructuras/química , Mucosa Nasal/metabolismo , Administración Intranasal , Proteína C-Reactiva/análisis , Protocolos Clínicos , Proteínas del Sistema Complemento/análisis , Fibrosis Quística/genética , Regulador de Conductancia de Transmembrana de Fibrosis Quística/efectos adversos , Método Doble Ciego , Terapia Genética/métodos , Vectores Genéticos , Interleucina-6/sangre , Líquido del Lavado Nasal , Reacción en Cadena de la Polimerasa , Factores de TiempoRESUMEN
Long-term treatment with ibuprofen twice daily, at doses that achieve peak plasma concentration (Cmax) >50 microg/ml, slows progression of lung disease in patients with cystic fibrosis (CF). Previous data suggest that Cmax >50 microg/ml is associated with a reduction in neutrophil (PMN) migration into the lung and that lower concentrations are associated with an increase in PMN migration. To estimate the threshold concentration at which ibuprofen is associated with a decrease in PMN migration in vivo, we measured the PMN content of oral mucosal washes in 35 healthy (age 19-40 years) and 16 CF (age 18-32 years) subjects who took ibuprofen twice daily for 10 days in doses that achieved Cmax 8 to 90 microg/ml. Cmax >50 microg/ml was associated with a 31 +/- 7% (mean +/- S.E.M.) reduction in PMNs in CF (n = 11, p < 0.001) and 25 +/- 6% reduction in PMNs in healthy subjects (n = 16, p < 0.001). Increasing concentrations above 50 microg/ml was not associated with a greater decrease in PMNs. The reduction in PMN migration was consistently present 12 h after a dose, but not after 24 h. Cmax <50 microg/ml was associated with an increase in PMNs of approximately 40%. These results suggest that Cmax >50 microg/ml and twice daily dosing of ibuprofen are required to decrease PMN migration, and reinforce the current recommendation that pharmacokinetics should be performed in CF patients prescribed ibuprofen.
Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Fibrosis Quística/patología , Ibuprofeno/farmacología , Neutrófilos/efectos de los fármacos , Antiinflamatorios no Esteroideos/farmacocinética , Área Bajo la Curva , Movimiento Celular/efectos de los fármacos , Fibrosis Quística/metabolismo , Humanos , Ibuprofeno/farmacocinética , Mucosa Bucal/patología , Neutrófilos/patologíaRESUMEN
CPX (8-cyclopentyl-1,3-dipropylxanthine) is a novel compound currently under development as a potential treatment for cystic fibrosis (CF). The drug has been shown to increase chloride efflux and CFTR trafficking in vitro in CF airway cells. This phase I multicenter, single-dose, placebo-controlled trial was performed at four institutions. Thirty-seven subjects homozygous for the Delta F(508) allele were studied in an escalating dose protocol of seven single-dose cohorts (1, 3, 10, 30, 100, 300, and 1,000 mg) to evaluate the safety, pharmacokinetics, and efficacy of CPX. Efficacy was determined using nasal transepithelial potential difference and sweat chloride measurements prior to dosing and at 1, 2, and 4 hr postdose. The incidence of adverse events in the treatment group was similar to that with placebo, indicating safety of the single doses studied. One serious adverse event (an acute pulmonary exacerbation) occurred 13 days after dosing, and was not considered related to the study drug. The maximal plasma CPX concentration and total amount of CPX absorbed appeared to be linearly related to dose, but was highly variable throughout the dose range studied, suggesting inconsistent absorption. There was no apparent effect of single-dose administration on either nasal transepithelial potential difference or sweat chloride measurements. The positive safety and pharmacokinetic findings of this study support continued development of CPX as a potential therapeutic for CF.
Asunto(s)
Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Fibrosis Quística/tratamiento farmacológico , Fragmentos de Péptidos/genética , Antagonistas de Receptores Purinérgicos P1 , Xantinas/administración & dosificación , Adolescente , Adulto , Cloruros/análisis , Fibrosis Quística/genética , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino , Potenciales de la Membrana , Mutación Missense , Mucosa Nasal/fisiología , Análisis de Regresión , Proyectos de Investigación , Sudor/química , Resultado del Tratamiento , Xantinas/efectos adversos , Xantinas/farmacocinética , Xantinas/uso terapéuticoRESUMEN
One of the goals of current research in cystic fibrosis (CF) is to develop treatments that correct or compensate for defects in function of the cystic fibrosis transmembrane regulator (CFTR) gene. The use of outcome measures that assess CFTR function such as nasal potential difference (NPD) measurements and sweat chloride determinations will be required to evaluate the efficacy of such treatments in multicenter clinical trials. The purpose of this work was to identify the sources and magnitude of variability in NPD and sweat chloride measurements when performed at multiple centers. For the variance component analysis presented here, we used NPD and sweat chloride measurements from 37 subjects with CF participating in a phase I, four-center clinical trial of CPX (8-cyclopentyl-1,3-dipropylxanthine), a drug intended to enhance trafficking of Delta F508 CFTR to the cell membrane. The specific techniques used to measure these outcomes were not standardized, and varied between the four sites. Variability of both NPD measurements (baseline potential difference during infusion with Ringer's solution; change in response to addition of 0.1 mM amiloride; and subsequent change in response to perfusion with low chloride solution containing 0.1 mM amiloride and 0.01 mM isoproterenol) and sweat chloride measurements differed significantly between study sites. For change in NPD, one study site had significantly greater variability (lower reproducibility) of measurement than the other three sites. For sweat chloride measurements, reproducibility was lower at two of the sites relative to the other two sites. Sample size calculations showed that lower reproducibility at one or more sites can substantially reduce the power of studies using NPD or sweat chloride determinations as outcome measures. Standardization of measurement protocols, careful operator training and certification, and ongoing monitoring of individual operator performance may help to improve reliability in multicenter trials.