Exebacase in Addition to Daptomycin Is More Active than Daptomycin or Exebacase Alone in Methicillin-Resistant Staphylococcus aureus Osteomyelitis in Rats

Bacteriophage-derived lysins are being developed as anti-infective agents. In an acute osteomyelitis methicillin-resistant (MRSA) model, rats receiving no treatment or treatment with daptomycin, exebacase (CF-301), or daptomycin plus exebacase had means of 5.13, 4.09, 4.65, and 3.57 log CFU/gram of bone, respectively. All treated animals had fewer bacteria than did untreated animals ( ≤ 0.0001), with daptomycin plus exebacase being more active than daptomycin ( = 0.0042) or exebacase ( < 0.001) alone.