What is the first line treatment for Community-Acquired Pneumonia (CAP)?

From the Guidelines

The first line treatment for community-acquired pneumonia (CAP) in outpatients without comorbidities is typically amoxicillin 1 gram three times daily for 5 days, as recommended by the most recent guidelines 1. For patients with comorbidities or risk factors for drug-resistant pathogens, a combination of amoxicillin-clavulanate 875/125 mg twice daily or a respiratory fluoroquinolone (levofloxacin 750 mg daily or moxifloxacin 400 mg daily) for 5 days is recommended. In patients with penicillin allergies, doxycycline 100 mg twice daily or a macrolide like azithromycin 500 mg on day 1 followed by 250 mg daily for 4 more days can be used, though macrolide resistance is increasing. The choice of antibiotic should be based on the severity of the disease, the presence of comorbidities, and the risk of drug-resistant pathogens. Some key points to consider when choosing an antibiotic include:

• The patient's medical history and current health status
• The severity of the pneumonia
• The presence of comorbidities, such as chronic obstructive pulmonary disease (COPD) or heart disease
• The risk of drug-resistant pathogens, such as methicillin-resistant Staphylococcus aureus (MRSA) or Pseudomonas aeruginosa
• The potential for allergic reactions or interactions with other medications For hospitalized non-ICU patients, a beta-lactam (ampicillin-sulbactam, ceftriaxone, or cefotaxime) plus a macrolide is preferred, as stated in the guidelines 1. Severely ill patients requiring ICU admission should receive a beta-lactam plus either a respiratory fluoroquinolone or azithromycin. These regimens target the most common CAP pathogens including Streptococcus pneumoniae, Haemophilus influenzae, and atypical organisms like Mycoplasma pneumoniae. Treatment should be initiated promptly after diagnosis, ideally after obtaining appropriate cultures but before results are available, as early appropriate therapy reduces mortality and complications, as supported by the evidence 1.

From the FDA Drug Label

Clinical success (cure plus improvement) with levofloxacin at 5 to 7 days posttherapy, the primary efficacy variable in this study, was superior (95%) to the control group (83%). The clinical success rate in patients with atypical pneumonia due to Chlamydophila pneumoniae, Mycoplasma pneumoniae, and Legionella pneumophila were 96%, 96%, and 70%, respectively.

The first line treatment for Community-Acquired Pneumonia (CAP) is not explicitly stated in the label, but levofloxacin is presented as a treatment option with high clinical success rates.

• Key points:
  • Levofloxacin has a clinical success rate of 95% in the treatment of CAP.
  • The drug is effective against atypical pneumonia caused by Chlamydophila pneumoniae, Mycoplasma pneumoniae, and Legionella pneumophila.
  • Levofloxacin is also effective against multi-drug resistant Streptococcus pneumoniae (MDRSP). 2

From the Research

First-Line Treatment for Community-Acquired Pneumonia (CAP)

The first-line treatment for CAP varies by disease severity and etiology.

• For hospitalized patients with suspected bacterial CAP and without risk factors for resistant bacteria, treatment with β-lactam/macrolide combination therapy, such as ceftriaxone combined with azithromycin, for a minimum of 3 days is recommended 3.
• Levofloxacin, a fluoroquinolone, has a broad spectrum of activity against several causative bacterial pathogens of CAP and can be used as a monotherapy in patients with CAP 4.
• High-dose levofloxacin treatment has been used as single-agent therapy for treating CAP, covering atypical pathogens, and has shown excellent clinical and microbiological efficacy with a safety profile comparable to that of ceftriaxone plus azithromycin therapy 5.
• The clinical response rate and microbiological response rate of levofloxacin and combination therapy (amoxicillin/clavulanate plus clarithromycin) were similar in a randomized, open-label study 6.

Considerations for Treatment

• The selection of empirical antibacterial therapy should consider disease severity and evaluate the likelihood of a bacterial infection or resistant infection and risk of harm from overuse of antibacterial drugs 3.
• Patients with CAP should be tested for COVID-19 and influenza when these viruses are common in the community, as their diagnosis may affect treatment and infection prevention strategies 3.
• Systemic corticosteroid administration within 24 hours of development of severe CAP may reduce 28-day mortality 3.