Exebacase for patients with Staphylococcus aureus bloodstream infection and endocarditis

Area of Science:

• Infectious Diseases
• Microbiology
• Pharmacology

Background:

• Novel therapeutics are urgently needed for Staphylococcus aureus bloodstream infections (BSIs), particularly drug-resistant methicillin-resistant S. aureus (MRSA).
• Exebacase, a pioneering antistaphylococcal lysin, offers rapid bacteriolysis, biofilm eradication, and synergistic effects with antibiotics.

Purpose of the Study:

• To evaluate the efficacy of exebacase as a novel therapeutic agent for S. aureus BSIs.
• To assess clinical outcomes in patients treated with exebacase plus antibiotics versus antibiotics alone.

Main Methods:

• A superiority-design study involving 121 patients with S. aureus BSI/endocarditis.
• Random assignment to receive a single dose of exebacase or placebo, alongside standard-of-care antibiotics.
• Primary endpoint: clinical responder rate on day 14.

Main Results:

• Overall clinical responder rates on day 14 were 70.4% (exebacase) vs. 60.0% (placebo).
• In the MRSA subgroup, responder rates were significantly higher: 74.1% vs. 31.3%.
• Adverse events were similar between groups; exebacase demonstrated a notable reduction in mortality and hospital readmissions for MRSA patients.

Conclusions:

• Exebacase demonstrates proof of concept as a direct lytic agent for treating BSIs.
• The study supports further investigation of exebacase, particularly for MRSA BSIs, due to promising efficacy and safety findings.