Evaluation of Safety, PK and Immunomodulatory Effects of AB103 in Necrotizing Soft Tissue Infections Patients

Inclusion Criteria * Clinical diagnosis of NSTI due to bacterial infection (Necrotizing Fasciitis, Group A streptococcal infection or non group A streptococcal infection, Fournier's gangrene, Bacterial synergistic gangrene, Synergistic Necrotizing Cellulitis, Clostridial gas gangrene/ myonecrosis) that may be supported by specific signs and symptoms, e.g. tense edema outside area of compromised skin, pain disproportionate to appearance, skin discoloration, ecchymosis, blisters/bullae, necrosis, tense edema, crepitus and/or subcutaneous gas AND a decision for urgent surgical exploration and debridement; * Patient who did not receive the study drug prior to the surgery need to have a definite diagnosis of NSTI confirmed surgically (e.g. presence of necrotic tissue, thrombosed vessels in the subcutaneous tissue, lack of bleeding and "dishwater" (cloudy, thin, gray) fluid) in order to get the drug during or after operation; * IV drug administration within 6 hours from the clinical diagnosis and from the documented decision to have an urgent surgical exploration and debridement; * Signed and dated ICF as defined by the IRB and, if applicable, California Bill of Rights. By signing the ICF, the patient agrees to release any medical records pursuant to current Health Insurance Portability and Accountability Act (HIPAA) Guidelines. If patient is unable to comprehend or sign the ICF, patient's legally acceptable representative may sign the ICF; Exclusion Criteria * Age \< 18 years; …