In vitro: A previous study compared the molecular interactions of the streptogramin combinations Synercid (type A, dalfopristin; type B, quinupristin) and NXL 103 (type A, flopristin; type B, linopristin) with the Escherichia coli 70S ribosome. Results showed that the streptogramin A and B components in Synercid and NXL 103 exhibited synergistic antimicrobial activity against certain pathogenic bacteria. Moreover, in transcription-coupled translation assays, only combinations including dalfopristin, the streptogramin A component of Synercid, showed synergy [1].

In vivo: A previous animal study aimed to investigate the efficacy of quinupristin/dalfopristin in the prevention of prosthetic graft infection in a rat subcutaneous pouch model. Results showed that quinupristin/dalfopristin had significantly higher efficacy than levofloxacin and doxycycline. In addition, only the group treated with quinupristin/dalfopristin combined with levofloxacin or doxycycline showed no evidence of staphylococcal infection [2].