9 October 2018 - - US-based biotechnology company AmpliPhi Biosciences Corp. (NYSE American: APHB) has presented clinical case series data from the company's ongoing expanded access program for its investigational bacteriophage therapeutic, AB-SA01 targeting Staphylococcus aureus (S. aureus), at the IDWeek 2018 conference in San Francisco, the company said.

Prof. Jonathan Iredell, Senior Staff Infectious Diseases Physician at the Westmead Hospital in Sydney, director of Centre for Infectious Diseases and Microbiology at the Westmead Institute of Medical Research and Professor of Medicine and Microbiology at the University of Sydney, gave a presentation "Adjunctive bacteriophage therapy for severe Staphylococcal sepsis," including data on 13 patients suffering from severe S. aureusinfections, who were treated with AB-SA01 as an adjunct to antibiotics at the Westmead Hospital in 2017-2018.

The potential treatment of S. aureusbacteremia with AB-SA01 was also the subject of the company's recent Type B meeting with the FDA. The treatment was conducted under emergency protocols per the Australian Therapeutic Goods Administration's Special Access Scheme.

Thirteen patients treated with AB-SA01 had severe S. aureus sepsis and/or bacteremia. The patients had not responded to prior conventional antibiotic therapy and were eligible for treatment with AB-SA01 under the Australian TGA SAS Category A, which allows therapy for a patient who is "seriously ill with a condition from which death is reasonably likely to occur within a matter of months, or from which premature death is reasonably likely to occur in the absence of early treatment."

Ten of the patients also suffered from infective endocarditis (infection of the endocardium, the inner lining of the heart chambers and heart valves), and five of these patients had prosthetic valve endocarditis, which can be particularly challenging to treat with antibiotics due to formation of bacterial biofilm.

Approximately 290 doses of AB-SA01 were administered intravenously and were well tolerated with no adverse events attributable to AB-SA01.

Eighty three percent of patients (10 out of 12) in the mITT population achieved treatment success at the end of therapy. Treatment success, as determined by the treating physician, was defined as a complete resolution or significant improvement of baseline signs and symptoms.

Initial gene expression data indicate that bacteriophage treatment may downregulate pro-inflammatory genes and upregulate anti-inflammatory genes, which could be important for treatment of patients with sepsis to prevent septic shock and for patients with endocarditis to prevent destruction of heart tissue.

AmpliPhi Biosciences is a clinical-stage biotechnology company focused on treating antibiotic-resistant infections using its proprietary bacteriophage-based technology.
The company's lead clinical stage product candidates, AB-SA01 and AB-PA01, target multidrug-resistant Staphylococcus aureus and Pseudomonas aeruginosa, which are included on the WHO's 2017 Priority Pathogens List.

Phage therapeutics are uniquely positioned to address the threat of antibiotic-resistance as they can be precisely targeted to kill select bacteria, have a differentiated mechanism of action, can penetrate and disrupt biofilms (a common bacterial defense mechanism against antibiotics), are potentially synergistic with antibiotics and have been shown to restore antibiotic sensitivity to drug-resistant bacteria.

Bacteriophages, or more simply "phages," are the natural predators of bacteria and are thought to be the most abundant life form on earth.

Phages have evolved an incredible diversity of strains that typically prey upon just a few closely related strains or species of bacteria, enabling phage therapies to precisely target pathogenic bacteria while sparing the beneficial microbiota. Phages can infect and kill bacteria, whether they are antibiotic-resistant or not, and even when they have formed protective biofilms.