Table 2.

Main trials with erdosteine 300 mg twice daily in chronic bronchitis/chronic obstructive pulmonary disease (COPD)

Study, year and reference no	Trial number identifier/name	Design	Study duration (weeks or days)	No. of patients	Disease characteristics	FEV1 (% predicted)	Outcomes
Fioretti and Bandera, 1991 [25]	NA	Double-blind, randomized,	26	132	Chronic bronchitis	NA	Significant reduction in incidence and severity of exacerbations and number of days absent from work due to exacerbation compared with placebo
Marchioni et al., 1995 [26]	ECOBES	Multicentre, double-blind, randomized	10 days at the latest	237	Acute exacerbation of chronic obstructive bronchitis	NA	Faster improvement in breathlessness, cough, and sputum viscosity with the combination of amoxicillin and erdosteine compared with antibiotic alone
Aubier et al., 1999 [27]	NA	Multicentre, double-blind, randomized, parallel-group	3	170	Stable chronic obstructive bronchitis with hypersecretion	NA	The global index of efficacy (frequency of the cough + severity of the cough + difficulty in breathing + dyspnea) and also the intensity and frequency of the cough statistically significant in favour of erdosteine compared to placebo
Moretti et al., 2004 [28]	EQUALIFE	Multicentre, double-blind, randomized, parallel-group	32	124	Stable COPD	59.2	Significant reduction in the number of AECOPDs and hospitalization days, and improvement in health-related quality of life, with a lower mean total COPD-related disease cost per patient compared to placebo
Dal Negro et al., 2017 [38]	NCT01032304; RESTORE	Multicentre, double-blind, randomized, parallel-group	52	445	Stable COPD (Stage II and III according to GOLD 2007)	51.8	Reduction in AECOPD rate by 19.4% and in duration of all AECOPDs by 24.6%, improvement in subject and physician subjective severity scores, and reduction in the use of reliever medication with erdosteine vs placebo

AECOPD acute exacerbation of COPD, FEV₁ forced expiratory volume in 1 s