Staphylococcus aureus Phage Product Candidate, AP-SA02

The three natural lytic phage that comprise our first-generation phage product candidate, AP-SA01, were chosen for their ability to cover approximately 95% of S. aureus clinical isolates, including multidrug-resistant strains. Human exposure obtained from two previously completed Phase 1 studies and through use under investigator Emergency IND, indicate that AP-SA01 is generally well-tolerated. AP-SA01 has advanced through a pre-IND meeting with the U.S. FDA.

Armata is developing a second-generation phage product candidate for S. aureus, known as AP-SA02, which offers significantly improved therapeutic attributes compared to AP-SA01.

Armata is committed to developing novel phage therapies that specifically address areas of high need which includes drug resistant and difficult to treat infections such as S. aureus bacteremia (SAB). We intend to file an IND Application with the U.S. FDA to initiate a Phase 1b/2, multi-center, randomized, double-blind, placebo-controlled dose escalation study that will assess the safety, tolerability, and prelimiary efficacy of AP-SA02 administered intravenously as an adjunct to best available antibiotic therapy for the treatment of SAB.

Armata received a $15 million Award through the U.S. Department of Defense (The Naval Medical Research Center: NMRC; The United States Army Medical Research Acquisition Activity USAMRAA; Defense Health Agency: DHA). This nondilutive funding will support IND enabling activities and the Phase 1b/2 study in bacteremia.

Target Market and Medical Need

Bacteremia is a bacterial infection of the bloodstream. A common diagnosis, the Centers for Disease Control and Prevention (CDC) estimates that up to 1.7 million people in the U.S. develop bacteremia each year. S. aureus is the most commonly identified pathogen in both hospital- and community-acquired blood stream infections. Annually in the U.S. there are approximately 200,000 hospitalizations for S. aureus bacteremia (SAB). Despite conventional antibiotics, mortality in SAB results in death of up to 40% of all cases and 57% of patients over the age of 85. Patients with comorbidities such as alcoholism, malignancy, diabetes, end-stage renal disease requiring hemodialysis, and immunosuppression are at even higher risk for death when SAB develops. Age-adjusted mortality assessments show that SAB mortality is higher than that of AIDS, tuberculosis, or viral hepatitis, and comparable to mortality rates for breast or prostate cancer. Outcomes are even poorer for SAB due to methicillin-resistant S. aureus (MRSA), classified as a serious threat to global health by the CDC and a high priority threat by the World Health Organization, with higher rates of complications and increased mortality as compared to methicillin-susceptible S. aureus (MSSA). Average hospital costs to patients with nosocomial SAB ranges between $40,000 (MSSA) and $114,000 (MRSA). Treatment failures are common in SAB, with highest rates due to MRSA. These failures can be attributed in part to poor penetration of some tissues by antibiotics, slow onset of bactericidal effects, emerging resistance patterns, and biofilm formation. While biofilms can render traditional antibiotics ineffective, phages may have the ability to penetrate the biofilm allowing rapid and efficient infection of the host and amplification at the site of infection. Daptomycin (approved in 2005; based on clinical cure rates of <50%) and vancomycin are the only two antibiotics with label indications in the U.S. for the treatment of SAB, and the emergence of drug-resistant S. aureus isolates, including to these two standard of care drugs, represents a major threat in terms of increasing morbidity, mortality and health care utilization.