High in Vitro Susceptibility to the First-in-Class Spiropyrimidinetrione Zoliflodacin among Consecutive Clinical Neisseria gonorrhoeae Isolates from Thailand and South Africa

We evaluated the in vitro susceptibility to the first-in-class spiropyrimidinetrione zoliflodacin among recent consecutive clinical Neisseria gonorrhoeae isolates cultured in Thailand (n = 99) (in 2018) and South Africa (n = 100) (in 2015 to 2017). Zoliflodacin was highly active in vitro against all tested isolates (MIC range, 0.004 to 0.25 μg/ml; MIC50, 0.064 μg/ml; MIC90, 0.125 μg/ml), with no cross-resistance to any of the seven comparator antimicrobials. Our data support the initiation of the global phase 3 randomized controlled clinical trial of zoliflodacin for uncomplicated gonorrhea.