Study Name: Efficacy of Famotidine in hospitalized adult COVID-19 patients

Study Type: Retrospective cohort study

Study Period

Discharges between Feb 1st 2020 and May 31st 2020

Study Entry Cohort

Inclusions: Hospitalized adult COVID-19 patients, defined as patients over the age of 18 admitted for inpatient care with either: 


  • Patients with ongoing hospitalizations at the end of the study period (not yet discharged or deceased) 
  • Patients who underwent mechanical ventilation or who were deceased the day of or day after hospital admission (midnight to midnight).

Target Cohort

Administration of famotidine on the day of or day after hospital admission (midnight to midnight), regardless of route (intravenous or oral), dose, or duration of therapy.

Comparison Cohort

Patients who were not administered famotidine within the day of or day after admission to the hospital, including patients who did not receive famotidine at all during their hospital stay, as well as patients who may have received famotidine after the exposure timeframe, as defined above. 


  • Mechanical Ventilation occurring between hospital admission through earliest of (mechanical ventilation, discharge, 14 days of hospital admission)
  • Inpatient Death occurring between hospital admission through earliest of (death, discharge, 30 days of hospital admission)

Statistical Analysis

  • Descriptive statistics
  • Multivariate Cox proportional hazards model, using elastic net for variable selection for reduced model


  • Age 
  • Sex: M, F, Unknown/other 
  • Comorbidities -- ascertained using a 2 year (730 day) look-back period prior to the date of hospital admission, unless otherwise noted: 
    • Coronary heart disease
    • Heart failure
    • End-stage renal disease (<=365 days before – and not including – the date of hospital admission)
    • Diabetes
    • COPD
    • Hypertension
    • Obesity
    • Smoking status
    • Number of comorbidities, using the subset of individual comorbidities above (any, 1, 2, 3, 4+)