Effect of fudosteine, a cysteine derivative, on blood flow of tracheal microvasculature increased by airway inflammation

Pharmacokinetics and Bioequivalence of Fudosteine in Healthy Chinese Volunteers Under Fasting and Fed Conditions: A 4-Way Replicate Crossover Study

The bioequivalence of a generic fudosteine tablet vs a brand-named fudosteine tablet under fasting and fed conditions was evaluated in this study. This randomized, open-label, single-dose, 4-way replicate, crossover, bioequivalence study included 64 healthy Chinese subjects (fasting cohort, n = 32; fed cohort, n = 32) who were assigned to receive a single 200-mg dose of generic or brand-named fudosteine. Blood samples were collected before dosing and up to 24 hours after dosing. The plasma concentrations of fudosteine were analyzed by high-performance liquid chromatography-tandem mass spectrometry. Safety was monitored. There were no significant differences in maximum plasma concentration (C_max ), area under the plasma concentration-time curve (AUC) from time 0 to time t (AUC_0-t ), or AUC from time 0 to infinity (AUC_0-∞ ) between the test and reference formulations. However, food showed a significant effect on C_max , AUC_0-t , and AUC_0-∞ for both generic and brand-named fudosteine. The 90%CIs of the test/reference ratios of C_max , AUC_0-t, and AUC_0-∞ were within the range of 80% to 125% under both fasting and fed conditions. No serious adverse events were reported. The bioequivalence between generic and brand-named fudosteine under fasting and fed conditions was demonstrated. Both of them had good tolerance for healthy Chinese volunteers. In addition, food delayed the absorption of fudosteine, so taking this medicine before meals might be an optimized option.

Effect of fudosteine, a cysteine derivative, on airway hyperresponsiveness, inflammation, and remodeling in a murine model of asthma

AIMS

Fudosteine is a cysteine derivative that is used as an expectorant in chronic bronchial inflammatory disorders. It has been shown to decrease the number of goblet cells in an animal model. This study examined the effects of fudosteine on airway inflammation and remodeling in a murine model of chronic asthma.

MAIN METHODS

BALB/c mice were sensitized by an intraperitoneal injection of ovalbumin (OVA), and subsequently challenged with nebulized ovalbumin three days a week for four weeks. Seventy-two hours after the fourth challenge, airway hyperresponsiveness (AHR) and the cell composition of bronchoalveolar lavage (BAL) fluid were assessed. Fudosteine was administered orally at 10mg/kg or 100mg/kg body weight from the first to the fourth challenge.

KEY FINDINGS

We investigated the effects of fudosteine on the development of allergic airway inflammation and airway hyperresponsiveness after chronic allergen challenges. The administration of fudosteine during the challenge with ovalbumin prevented the development of airway hyperresponsiveness and accumulation of lymphocytes in the airways. Eotaxin, IL-4, and TGF-β levels and the relative intensity of matrix metalloproteinase-2 and matrix metalloproteinase-9 (MMP-2 and MMP-9) in BAL fluid were reduced by the fudosteine treatment; however, the number of eosinophils in BAL fluid and serum IgE levels did not change. The expression of TGF-β, the development of goblet cell hyperplasia, subepithelial collagenization, and basement membrane thickening were also reduced by the fudosteine treatment.

SIGNIFICANCE

These results indicate that fudosteine is effective in reducing airway hyperresponsiveness, airway inflammation, and airway remodeling in a murine model of chronic asthma.

Bronchoscopic imaging of pulmonary mucosal vasculature responses to inflammatory mediators

In current clinical practice, the initial stage in the detection of pulmonary airway disease is the clinician's interpretation of a bronchoscopy procedure. Due to the nature of this form of detection, diseases are often well advanced upon discovery. This paper proposes a new method for examining the pulmonary airway microcirculatory system via fluorescein imaging techniques similar to those used extensively in ophthalmology. Through the use of a specialized bronchoscopy imaging system we are able to successfully show that fluorescein emission detected in the rabbit trachea exhibits a clear response to inflammatory mediators and thus to changing local vascularity. The clinical implications of this technique are extensive including most importantly the potential use as an evaluation tool for pulmonary disease evaluation and likely other endoscopically accessible organs.