Eligibility criteria

Inclusion criteria
  • 2–59 months of age

    Cough <14 days or difficulty breathing

    Fast breathing for age (≥50 breaths·min−1 among children 2–11 months; ≥40 breaths·min−1 among children ≥12 months)

Exclusion criteria
  • Severe respiratory distress (head nodding, nasal flaring, grunting, and/or chest indrawing)

    Hypoxaemia (SpO2<90%)

    Resolution of fast breathing after bronchodilator challenge, if wheezing at screening examination

    WHO IMCI general danger signs (lethargy or unconsciousness, convulsions, vomiting everything, inability to drink or breastfeed)

    Stridor when calm

    HIV-1 seropositivity or HIV-1 exposure (children <24 months of age with a HIV-infected mother)

    Severe acute malnutrition (weight for height/length < −3 sd, mid-upper arm circumference <11.5 cm, or peripheral oedema)

    Possible tuberculosis (coughing ≥14 days)

    Anaemia with haemoglobin <8.0 g·dL−1

    Severe malaria (positive malaria rapid diagnostic test with any WHO IMCI general danger sign, stiff neck, abnormal bleeding, clinical jaundice, or haemoglobinuria)

    Known allergy to penicillin or amoxicillin

    Receipt of an antibiotic treatment in the 48 h prior to the study

    Hospitalised within 14 days prior to the study

    Living outside the study area

    Any medical or psychosocial condition or circumstance that, in the opinion of the investigators, would interfere with the conduct of the study or for which study participation might jeopardise the child's health

    Any nonpneumonia acute medical illness which requires antibiotic treatment per local standard of care

    Participation in a clinical study of another investigational product within 12 weeks prior to randomisation or planning to begin participation during this study

    Prior participation in the study during a previous pneumonia diagnosis

SpO2: arterial oxygen saturation measured by pulse oximetry; WHO: World Health Organization; IMCI: Integrated Management of Childhood Illnesses.