Antimicrobial Activity of Aztreonam-Avibactam and Comparator Agents When Tested against a Large Collection of Contemporary Stenotrophomonas maltophilia Isolates from Medical Centers Worldwide.

Aztreonam-avibactam was tested against 1,839 Stenotrophomonas maltophilia isolates collected worldwide and demonstrated potent activity against isolates from all geographic regions and infection types (overall MIC50/90, 4/4 mg/liter; 97.8% inhibited at ≤8 mg/liter). Trimethoprim-sulfamethoxazole (TMP-SMX) (MIC50/90, ≤0.5/1 mg/liter; 95.4% susceptible) and minocycline (MIC50/90, 0.5/2 mg/liter; 99.5% susceptible) were also very active. Aztreonam-avibactam inhibited 84.7% of non-TMP-SMX-susceptible isolates at ≤8 mg/liter. Aztreonam-avibactam may represent a valuable option for the treatment of S. maltophilia infections, addressing a major unmet medical need.