Global update on the in vitro activity of tigecycline and comparators against isolates of Acinetobacter baumannii and rates of resistant phenotypes (2016–2018)

•Treatment options for carbapenem-resistant A. baumannii are limited.•The ATLAS program collects antimicrobial activity data against A. baumannii worldwide.•Regional tigecycline and colistin MIC90s were 1 or 2 mg/L against A. baumannii.•1.6%–10.2% of meropenem-resistant A. baumannii in each region were colistin-resistant.•Rates of meropenem resistance were highest in Africa/Middle East and Latin America.