Study Comparing the Safety and Efficacy of Cethromycin to Clarithromycin for the Treatment of Community-Acquired Pneumonia

Inclusion Criteria: * Ambulatory male or female, 18 years of age or older * If female, non-lactating and at no risk or pregnancy (post-menopausal or must use adequate birth control) * Positive Chest X-ray consistent with diagnosis of bacterial pneumonia * Must be a suitable candidate for oral antibiotic therapy and must be able to swallow capsules intact * Recent history of respiratory illness consistent with the clinical signs and symptoms of bacterial CAP * Must be able to produce sputum Exclusion Criteria: * Prior hospitalization within previous 4 weeks * Residence at a chronic care facility * Active tuberculosis (or other mycobacterial infection, empyema, lung abscess, pulmonary embolism, pulmonary edema, cystic fibrosis, tumor (primary or metastatic) involving the lung, bronchial obstruction, a history of post-obstructive pneumonia (Chronic Obstructive Pulmonary Disease \[COPD\] is not exclusionary), known or suspected Pneumocystis carinii pneumonia * Treatment with long-acting antimicrobial agents within the last 4 weeks, treatment with ceftriaxone, azithromycin or dirithromycin antibiotic within the last 7 days, or subjects who have received more than 24 hours of treatment with other antibiotics within 7 days prior to study drug administration * Any infection which requires the use of a concomitant antimicrobial agent * History of hypersensitivity or allergic reactions to macrolide, ketolide, quinolone, azalide or streptogramin antimicrobials * Treatment with another investigational drug within the last 4 weeks * Females who are pregnant or lactating * Subjects with known significant renal or hepatic impairment or disease * Subjects with a history of impaired renal function * Evidence of uncontrolled clinically significant cardiovascular, pulmonary, metabolic, gastrointestinal, neurological or endocrine disease, malignancy, or other abnormality (other than the disease being studied) * Subjects who would require parenteral antimicrobial therapy for the treatment of pneumonia * Any underlying disease or condition that would interfere with the completion of the study procedures and evaluations or absorption of the study drug * Currently receiving or are likely to require any of the following medications during the period between 2 weeks prior to Evaluation 1 and within 24 hours after the last dose of study drug: astemizol (Hismanal®) or pimozide (Orap®) * Currently receiving or are likely to require any of the following during the period from Evaluation 1 and within 24 hours after the last dose of study drug: theophylline or theophylline analogues (unless adequately monitored), carbamazepine, dexamethasone, phenobarbital, phenytoin, St. John's Wort, lamotrigine, troglitazone, warfarin and digitalis glycoside. Other barbiturates may be used with careful monitoring * Subjects who are currently receiving or who are likely to require any of the following medications during the period between Evaluation 1 and 4: other systemic antibiotic therapy, rifampin or rifabutin * Immunocompromised subjects, subjects receiving immunosuppressive agents, subjects with known human immunodeficiency virus (HIV) infections and history of acquired immune deficiency syndrome (AIDS) defining conditions or CD4+ T-lymphocyte count \<200. * Subject with known or suspected central nervous system (CNS) disorder that predisposes them to seizures/lower seizure threshold (e.g., severe cerebral arteriosclerosis, epilepsy) * Previous treatment with cethromycin * Subjects with signs of septic shock (e.g., mental confusion, severe hypoxemia, severe hypotension, any other condition requiring intensive care unit \[ICU\] admission)