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

Primary Objective: To evaluate the clinical efficacy of pristinamycin at a dose of 2g x 2/day for 2 days then 1g x 3/day for 5 to 7 days versus amoxicillin 1g x3 /day for 7 to 9 days, 5 to 9 days after the end of treatment. Secondary Objectives: To evaluate the clinical efficacy in a subpopulation bacteriologically documented at inclusion and according to procalcitonin level. To evaluate the efficacy of treatments against pneumococcus. To evaluate the rate of relapse and mortality 30±2 days after treatment is started. To document failures. To collect and follow up adverse events.