Inclusion Criteria:

• Outpatients,
• With a documented history of chronic bronchitis defined by one expectoration daily for at least three consecutive months over at least two consecutive years

• Presenting with an evident acute exacerbation of their disease defined by the presence of at least two of Anthonisen's criteria:

  • exacerbation of dyspnea,
  • increase in the expectoration volume,
  • increase in the expectoration purulence,

Exclusion Criteria:

• Acute bronchitis,
• Chronic obstructive pulmonary disease, those having FEV1 value <35% (FEV1: Forced Expiratory Volume in 1 second)
• Suspected pneumonia or bronchial pneumonia,
• Paroxysmal asthma or continuous dyspnea in asthma,
• Cystic fibrosis,
• Active tuberculosis,
• Lung cancer or lung metastasis,
• Severe bronchiectasia,
• Acute respiratory decompensation,
• Chronic respiratory insufficiency associated with resting hypoxemia,
• Patients requiring hospitalization for parenteral antibiotic treatment
• Patients with suspected or known bacterial infection other than study diseases, as well as associated systemic or intra-tracheal antibiotic treatment other than study treatment,
• Participating in another clinical study with any product within 30 days before the inclusion of study
• Known immunosuppression (AIDS and/or CD4+ lymphocytes < 200/mm3, neutropenia <1500/mm3, blood diseases or terminal stage cancer)
• Cardiovasculary, neurologic or other severe diseases interfering with the compliance with study protocol or confusing with results.

Conditions associated with study medications:

• Hypersensitivity against telithromycin , macrolides or any of the excipients,
• Congenital long QT syndrome or family history of congenital long QT syndrome (this possibility should be excluded with normal ECG) or known acquired QT interval prolongation,
• Treatment with CYP3A4 inducers (rifampicin, carbamazepine, phenytoin, phenobarbital, St-John's-wort) within 2 weeks prior to the study inclusion
• Possibility of treatment with ergot alkaloid derivatives, terfenadine, astemizole, pimozide, cisapride, simvastatin, athorvastatin or lovastatin during studies
• Congenital galactosemia, lactase deficiency glucose or galactose malabsorption syndrome,
• Pregnant or lactating women,
• Women with childbearing potential (e.g. ovulating, pre-menopausal or not surgically sterilized) and do not employ any effective contraception method The patients may not participate to the study more than once. The patients who were treated with study drugs previously may not participate to the study.

The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial.