Efficacy and safety of letosteine in the treatment of sputum thickening and expectoration difficulty in patients with respiratory diseases: a multicenter, randomized, double-masked, double dummy, positive drug parallel controlled trial. This study aimed to compare the efficacy and safety of letosteine and ambroxol hydrochloride for the treatment of sputum thickening and expectoration difficulty due to either acute or chronic respiratory diseases. Patients (n = 240) were randomized to receive either letosteine + placebo (50 mg thrice daily, Group A) or ambroxol hydrochloride + placebo (30 mg thrice daily, Group B) orally for 5-14 days. The primary outcomes comprised the total effectiveness rate and the total improvement rate. Secondary outcomes included: post-treatment IgA level changes
[Clinical evaluation of letosteine activity in the treatment of acute febrile bronchitis in children. Double-blind controlled study versus placebo]. A double blind vs placebo study was carried out to study the effect of letosteine on the symptoms and clinical course of paediatric patients suffering from acute febrile bronchitis. Forty children were recruited for the research: 20 were treated with letosteine in a dose of 25 mg x 3 g/die and 20 with placebo; treatment lasted 10 days. The following parameters were assessed during the trial: body temperature, cough, thoracic objectivity, respiratory function indices. The results of the study show that in the letosteine treated group there is a statistically significant decrease in fever, a favourable evolution of thoracic objectivity and an improvement
[Comparative clinical evaluation of two mucolytic agents: S-carboxy-methyl-cysteine and letosteine (author's transl)]. A controlled double-blind clinical trial comparing a noval medicament, letosteine, to a known bronchial fluidifier, S-carboxy-methyl-cysteine, was conducted on a total of 47 hospitalized patients suffering from various types of chronic obstructive lung disease. Daily observations were made on the patients themselves and on sputum samples obtained from them before, during and after the course of mucolytic therapy. When the code was broken at the end of the trial, there appeared no significant difference between the patient groups treated with the two drugs regarding either changes in respiratory symptoms or changes in sputum characteristics. Thus, in this study, letosteine (50
Development of a novel LC-MS/MS method for the determination of letosteine in human plasma and its application on pharmacokinetic studies. Letosteine has been found to be effective in treating patients with chronic bronchopneumopathies in clinical practice. To provide robust support for its pharmacokinetic and clinical studies, a rapid and sensitive method based on liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) was developed and validated for the analysis of letosteine in plasma samples. After protein precipitation, the plasma samples were separated on a reversed-phase C(18) column in less than 1.5 min. The LC-MS/MS system was performed in the positive ion multiple-reaction-monitoring (MRM) mode to produce intensive product ions of m/z 280.1→160.0 for letosteine and m/z