Pharmacokinetics, tolerability, and performance of a novel matrix transdermal delivery system of fentanyl relative to the commercially available reservoir formulation in healthy subjects.

A novel transdermal formulation of fentanyl-containing dipropylene glycol droplets dispersed in a silicone matrix with a rate-controlling membrane was developed. Healthy male subjects (n = 24) received repeated 72-hour applications of fentanyl (50 mug/h) as the novel matrix and the conventional reservoir formulations in a randomized, 2-way crossover study. Blood samples were collected, and serum concentrations of fentanyl were assayed using liquid chromatography with mass spectrometry detection. The mean area under the curve (AUCtau) and peak concentrations (C(max)) of the matrix formulation were 84 838 pg.h/mL and 1680 pg/mL, respectively. Ratio and 90% confidence intervals of AUCtau and C(max) between the 2 formulations were within 80% to 125%. Adherence of the matrix formulation was higher than the reservoir formulation (62.5 vs 56.2%, P < .0001), without affecting skin irritation. Vital signs and adverse events of the 2 formulations were similar in nature and frequency. The novel matrix formulation displayed enhanced adherence and resulted in similar pharmacokinetics and tolerability as the reservoir formulation.

Two open-label, randomized, crossover studies assessing the bioequivalence of ofloxacin administered as immediate-and extended-release formulations in healthy subjects.

BACKGROUND: Ofloxacin is a fluoroquinolone agent available as an immediate-release (IR) tablet formulation administered twice daily. An extended-release (ER) formulation of ofloxacin has been developed for oncedaily administration. OBJECTIVES: The present studies compared the pharmacokinetic (PK) and safety profiles of the ER and IR formulations of ofloxacin. METHODS: Based on specific inclusion and exclusion criteria, healthy adult male and female volunteers were selected to receive single and multiple oral doses of ofloxacin ER 400 mg QD and ofloxacin IR 200 mg BID in 2 separate open-label, randomized, crossover studies. Multiple blood samples were collected, and plasma concentrations of ofloxacin were analyzed using a high-throughput liquid chromatography system. PK parameters were calculated using noncompartmental methods. Safety was assessed in the clinical pharmacology unit based on vital signs, electrocardiograms (ECGs), and reported adverse events. The relationship of an adverse event to study drugs (definitely, probably, possibly, remotely, or unrelated) was assessed by the principal investigator. RESULTS: Forty healthy subjects were included in each study. Thirty-seven subjects (28 men, 9 women; mean age, 37 years; mean weight, 71.2 kg) completed the single-dose study, and 38 subjects (33 men, 5 women; mean age, 36 years; mean weight, 72.2 kg) completed the multiple-dose study. With the exception of 3 black subjects in each study of African-American origin, all subjects in both studies were white. The mean AUC(0-24) values for the ER formulation in the single-and multiple-dose studies (18.6 and 21.4 mg . h/L, respectively) were similar to those for the IR formulation (17.7 and 22.8 mg x h/L), with the 90% CIs falling between 80.0 and 125.0. Mean C(max) values for the ER formulation in the single- and multiple-dose studies (2.02 and 2.12 mg/L) were also similar to those for the IR formulation (1.74 and 1.85 mg/L). Under steady-state conditions, median T(max) values for the ER formulation were significantly longer than those for the IR formulation (5.00 vs 2.00 hours, respectively; P < 0.05). All vital signs and ECGs were within normal ranges during the single- and multipledose studies. Adverse events probably related to study drugs (eg, nausea, loose stools, emesis) were similar in nature and frequency between the 2 formulations. No serious adverse events were reported during either study. CONCLUSION: In these 2 trials in a selected group of healthy adult male and female volunteers, the ER and IR formulations of ofloxacin displayed a similar rate and extent of bioavailability and comparable safety profiles.

Estudo comparativo de biodisponibilidade relativa entre duas formulaçöes comerciais distintas de isotretinoína sistêmica existentes no Brasil / Comparative study of relative biovailability betwenn two Brazilian different commercial formulations of sistemic isotretinoin

Este estudo foi conduzido para avaliar a biodisponibilidade de uma nova formulação de isotretinoína sistêmica e de seu principal metabólico, a 4-oxo-ísotretinoína, relativo a um produto referência. Os dados das concentrações plasmáticas foram coletadas em 36 indivíduos sadios, em um delineamento cruzado de 2 vias, por um período de tempo de 144 horas. O plasma das amostras sanguíneas foram analisadas por um ensaio cromatográfico validado. Medidas farmacocinéticas indicadoras das taxas de absorção e eliminação dos fármacos, como concentração máxima (Cmax), área sob a curva de concentração até o tempo final de coleta t (Auc) e a área estimada até o infinito (Auc) foram analisadas sob modelo multiplicativo, isto é, utilizando log-transformado destas medidas. Os métodos para verificar a bioequivalência média entre T e R foram os intervalos de confiança e os dois testes unilaterais t. Conclui-se, então, que há bioequivalência média entre as duas formulações, baseados nos resultados obtidos pelas análises da isotretinoína e 4-oxo-isotretinoína.