Long term studies on almitrine bismesylate in COPD patients.

Almitrine bismesylate is a chemoreceptor agonist which has been shown to improve arterial blood gas values in chronic obstructive pulmonary disease (COPD) patients, possibly through better ventilation/perfusion matching. On these basis, long term studies were undertaken to evaluate the therapeutic activity of almitrine bismesylate in COPD. We report here the overall results of 4 studies: a 6 months double blind placebo controlled study on clinical and biochemical data in 200 patients. a 12 months double blind placebo controlled study on clinical and hemodynamic data in 15 patients. a 12 months open study on clinical and biochemical data in 108 patients. a 52 months follow-up including therapeutic gap in 8 patients. Almitrine bismesylate group showed significant improvement of PaO2 and PaCO2 levels as compared with placebo group; this was found after 6 months of treatment and persisted after 12 months of treatment. 75% of almitrine treated patients were considered as responders, i.e. improved PaO2 and PaCO2 levels by at least 5 mmHg (0.665 KPa). Almitrine bismesylate groups showed significantly decreased dyspnea scores, received significantly less hospital care for acute decompensation or pulmonary infection and showed no significant change in hemodynamic parameters. After 20 months treatment interruption, patients showed progressively impairmed blood gas levels. Almitrine bismesylate ws well tolerated; nausea was occasionally observed and usually disappeared. Paresthesia was observed in some patients with identified predisposition. Altogether, these studies showed long term efficacy and acceptability of almitrine bismesylate in COPD patients with chronic respiratory failure.(ABSTRACT TRUNCATED AT 250 WORDS)