Exebacase Gains Breakthrough Therapy Status for MRSA Bacteremia, Including Right-Sided Endocarditis

The Food and Drug Administration (FDA) has granted Breakthrough Therapy designation to exebacase (ContraFect) for the treatment of methicillin-resistant Staphylococcus aureus (MRSA) bacteremia, including right-sided endocarditis, when used in addition to standard of care anti-staphylococcal antibiotics in adult patients. 

Exebacase, a recombinantly-produced lysin, targets the peptidoglycan cell wall, which is vital to S. aureus bacteria. The designation is based on data from a phase 2 trial that included 116 patients with confirmed Staphylococcus aureus bacteremia including endocarditis.  Patients were randomized to receive exebacase (n=71) or placebo (n=45) in addition to standard of care antibiotics (eg, vancomycin or daptomycin for MRSA and a semi-synthetic penicillin or first-generation cephalosporin for methicillin-susceptible S. aureus).

Results showed patients treated with exebacase achieved clinically meaningful improvement in the primary efficacy end point of clinical response at Day 14 (responder rate: 70.4% vs 60.0% with standard of care antibiotics alone). Moreover, exebacase treatment was associated with higher responder rates at Day 14 in MRSA patients (P =.010) and in patients diagnosed with S. aureus bacteremia alone (P =.035), as well as in those with bacteremia including right-sided endocarditis (P =.028).

The Company is currently conducting a phase 3 superiority study (DISRUPT) to evaluate the efficacy and safety of exebacase in addition to standard of care antibiotics, compared with  standard of care antibiotics alone, for the treatment of patients with S. aureus bacteremia, including right-sided infective endocarditis. “Based on our interactions with the FDA regarding streamlined development of exebacase, this single phase 3 study, in addition to the full package of data generated to date, may serve as the basis of a Biologics License Application for FDA review and potential approval of exebacase,” said Cara Cassino, MD, Chief Medical Officer and Executive Vice President of Research and Development at ContraFect.

The FDA’s Breakthrough Therapy designation is designed to expedite the development and review of drugs for serious or life-threatening diseases with preliminary clinical evidence that the novel therapy may demonstrate substantial improvement over other available therapies.

For more information visit contrafect.com.