A review of published personalized phage therapy cases in clinical practice

The increase in antimicrobial resistant infections has fueled a resurgent interest in bacteriophage (phage) therapy. We conducted a literature review of personalized phage therapy cases in the peer-reviewed, English-language literature reported between 1/1/2005, to 8/31/2025 for which individual patient data were available, identifying and synthesizing data from a total of 323 patients described in 83 studies. Most patients (68%, 221/323) were treated with ≥ 2 phages (a phage cocktail). The median concentration of phages was 108 PFU/mL (IQR 107-109). Most patients (76%, 246/323) received antibiotics concurrent with phage therapy. The median duration of therapy was 10 days (IQR 5-21). The most common indications for phage therapy were skin/soft tissue, pulmonary, orthopedic, osteoarticular, and genitourinary infections. 144 patients received fixed (off-the-shelf) phage preparations whereas 179 received bespoke phage preparations (i.e., personalized therapy). For cases where outcomes data were available, 78% (253/323), experienced clinical improvement while the targeted pathogen was eradicated in 61% (177/290) of cases. Nine patients had treatment withdrawn due to tolerability concerns. These data indicate that there is substantial heterogeneity in current personalized phage therapy clinical practices but that this approach can be successful.