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Pseudomonas aeruginosa is an opportunistic pathogen associated with infections of immune compromised individuals. These bacterial infections often present as biofilms that are typically refractory to antibiotic therapy, and which complicate and limit therapeutic options. For these reasons, it is vital to examine whether phage therapy offers a useful alternative for treating P. aeruginosa infections. Although few approved clinical trials have tested the efficacy of phage therapy in Western medicine, no such studies have reported harmful side effects. Thus, available evidence suggests that therapeutic applications of phages are safe for human use. However, few studies have examined the ability of phage to destroy P. aeruginosa biofilms on indwelling medical prostheses, which would be crucial for phage therapy as a truly viable alternative. We examined the ability of phage to eradicate P. aeruginosa biofilms on two materials used in prosthetic grafts alone and in the presence of antibiotics (ciprofloxacin and/or ceftazidime). Biofilms were grown in culture on pieces of Dacron or Gore-Tex then exposed to phage and/or antibiotics. Phage were selected from a library of over 50 candidate environmental isolates and a three-phage cocktail was created. Each phage in the cocktail was experimentally evolved via serial passage on the clinical isolate to select for improved killing (higher phage virulence) on host bacteria. This clinical strain and phage cocktail were then used in modified Minimum Biofilm Eliminating Concentration (MBEC) assays that examined phage ability to destroy the biofilm alone, in combination, and in the presence/absence of antibiotics. Our results showed effective removal of biofilms by individual phage and phage cocktails for biofilms grown on both Dacron and Gore-Tex. Antibiotics alone were unable to eliminate biofilms at 2x the minimum inhibitory concentration and we did not observe antagonism between phage and antibiotics. The use of phages to eliminate biofilm on indwelling medical prosthetic grafts, therefore, shows promise and may be used in addition to traditional antibiotics.