DARWIN EU® - Drug Utilisation Study on Antibiotics in the ‘Watch’ category of the WHO AWaRe classification of antibiotics for evaluation and monitoring of use

Study type

• Study topic:
  Human medicinal product
• Study type:
  Non-interventional study
• Scope of the study:
  Drug utilisation
• Data collection methods:
  Secondary use of data

Non-interventional study

• Non-interventional study design:
  Cohort

Study drug and medical condition

• Medicinal product name, other:
  All antibiotics on the WHO AWaRe watch category 2023

Population studied

• Short description of the study population:
  The study domain includes all persons present in the data sources in the study period: 01/01/2012 to 31/12/2024 (or the latest available date) with at least 365 days observation time. This will be used as the denominator population for calculating incidence rates.

Study design details

• Study design:
  • Population-level cohort study (Objective 1, Population-level drug utilisation study on ‘Access, Watch, ; Reserve’ categories antibiotics) ; • New drug user cohort study (Objectives 2 and 3, Patient-level drug utilisation analysis with regard to ; duration and indication of antibiotics use)
• Main study objective:
  1. To investigate the incidence of use of antibiotics (from the WHO AWaRe Watch category) stratified by age, sex, calendar year/month, and antibiotics class during the study period 2012-2024.; 2. To characterise antibiotic (WHO AWaRe Watch category 2023) use by duration of use over the study period 2012 to 2024 stratified by calendar year and by antibiotics class.; 3. To characterise antibiotic use (WHO AWaRe Watch category 2023) by indication of use over the period 2012 to 2024 stratified by calendar year and by antibiotics class.;
• Setting:
  This study was conducted using routinely collected data from 12 primary/secondary care data sources in the DARWIN EU® network of data partners from 11 European countries. All data were a priori mapped to the OMOP CDM.
• Summary results:
  CONCLUSION ; This multi-country analysis highlights variation in antibiotic use across the WHO 2023 AWaRe categories. In the Access group, penicillins, β-lactam/β-lactamase inhibitors, 1st-generation cephalosporins, and nitrofuran derivatives were most prescribed, with amoxicillin, amoxicillin–clavulanic acid, and nitrofurantoin leading. Declines in broad-spectrum antibiotics and moderate increases in narrow-spectrum options such as pivmecillinam have occurred. The Watch category showed consistently higher use of macrolides, fluoroquinolones, and cephalosporins compared with other Watch antibiotics, with azithromycin, ciprofloxacin, and cefuroxime being the most commonly prescribed agents. Despite decreasing trends after 2018, broad-spectrum use remained, with seasonal peaks for respiratory and urinary infections and higher incidence rates in females and older adults. The Reserve category displayed low but increasing use of linezolid, daptomycin, and tigecycline, reflecting their expanding role in resistant infections. ; Collectively, these findings demonstrate both progress and ongoing challenges in optimizing antibiotic use.