Study to Compare the Efficacy of Pristinamycin (Pyostacine ®) Versus Amoxicillin in the Treatment of Acute Community Acquired Pneumonia

Inclusion criteria: Male or female more than 18 years old with a presumed bacterial acute community acquired pneumonia presenting a PORT score of II or III (Fine II or III). The acute community acquired pneumonia is defined by: * Pulmonary x-ray (carried out within the 48 hours prior to randomization) showing new lobar or multilobar infiltrates. * At least 4 functional and/or clinical symptoms from among the following: * Fever characterized by a temperature of more than 38.5 at least once within 24h prior to inclusion. * Appearance or aggravation of a cough. * Appearance of purulent expectoration. * Appearance or aggravation of dyspnoea. * Tachypnoea * Chest pain * A characteristic sign on percussion and/or auscultation associated with a pulmonary condensation focus. Exclusion criteria: Patients having been diagnosed with legionellosis. Patients having received systemic antibiotic therapy of over 24 hours within the week preceding the start of study treatment. Associated neoplasm (active cancer \[of whatever type, solid or haematological\] or diagnosed within the year other than basocellular skin cancer). Severe or very severe chronic obstructive pulmonary disease (COPD) (GOLD3 and GOLD4). History of bacterial pneumonia in the past 12 months. Bronchopulmonary diseases likely to interfere with the assessment of the therapeutic response. Known hypersensitivity to streptogramins, penicillin and other betalactamines or excipients of the treatments studied. History of severe skin reaction after taking pristinamycin or amoxicillin. Kidney disease (chronic kidney failure or creatinine clearance ≤30 mL/minute). Patients treated with allopurinol, colchicine, immunosuppressants (cyclosporin, tacrolimus, mycophenolate mofetil, methotrexate, biotherapies) oral anticoagulants in the previous 6 months or during the study. Known HIV infection, whatever the stage. The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial.