A non-interventional prospective study of the efficacy and tolerability of Elmucin® (erdosteine) in patients with acute bronchitis in real clinical practice (OPERA)

Acute bronchitis is a common respiratory tract disease, the key pathogenetic mechanism of which is abnormal rheological properties of bronchial secretions. Despite the availability of various mucolytic agents, their comparative effectiveness remains insufficiently studied.

The aim. To evaluate the efficacy and safety of Elmutsin® (erdosteine) as part of combination therapy for acute bronchitis in real­world clinical practice.

Methods. The study included 120 outpatients (3 groups of 40 patients each): erdosteine (capsules 300 mg), ambroxol (tablets 30 mg), and acetylcysteine (powder 200 or 600 mg). Demographic and clinical data were collected; efficacy was assessed using patient diaries, the Bronchitis Severity Score (BSS), the Breathlessness, Cough and Sputum Scale (BCSS), a visual analogue scale (VAS) for cough intensity, and the Clinical Global Impression (CGI) scale. The primary endpoint was the proportion of patients achieving clinical improvement by Visit 3 according to patient diary data. Descriptive statistics were used for analysis, with a significance threshold of p < 0.05.

Results. By Visit 3, clinical improvement was achieved in the vast majority of patients across all three groups. Despite initially higher disease severity in the erdosteine group compared with the ambroxol group (BSS, VAS, CGI­S; p = 0.037, 0.027, and 0.002, respectively), differences between groups were no longer significant by Visit 3. Compared with acetylcysteine, the erdosteine group showed statistically significantly lower scores for BSS (0.88 ± 0.85 vs 1.75 ± 1.35; p < 0.001), BCSS (1.03 ± 0.97 vs 2.00 ± 1.52; p = 0.002), VAS (5.56 ± 5.86 vs 11.75 ± 12.70; p = 0.003), and CGI­I (1.30 ± 0.46 vs 1.60 ± 0.50; p = 0.013). According to patient diary, symptom regression in the erdosteine group was faster starting from day 4 – 5 of therapy. One adverse reaction (epigastric pain, acetylcysteine group) was recorded; no serious adverse reactions occurred.

Conclusion. Erdosteine holds a leading position among the studied mucolytic agents in the treatment of acute bronchitis. Its multifaceted pleiotropic action on pathogenetic mechanisms of the disease, combined with a favorable safety profile and rapid onset of clinical effect, makes it the drug of choice in patients with acute bronchitis.

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