About Phage Therapy
What is Phage Therapy?
Phage therapy is a treatment approach that utilizes bacteriophages (viruses that infect and kill bacteria) to treat bacterial infections, especially those resistant to conventional antibiotics. It involves delivering phages to a patient to specifically target and eliminate disease-causing bacteria. This method offers a potential alternative or supplement to antibiotics, with the advantage of potentially minimizing harm to the body's normal microbiota.
Antibiotic Resistance
Bacterial antimicrobial resistance occurs when changes in bacteria cause the drugs used to treat infections to become less effective. This has emerged as one of the leading public health threats of the 21st century. A 2022 study conducted by a variety of antimicrobial resistance collaborators in The Lancet found that approximately 1.27 million deaths in 2019 were found to be attributable to antibiotic resistance. The study also found approximately 4.95 million deaths in 2019 to correlate to antibiotic resistance. These statistics provide conclusive evidence that an alternative to antibiotics is needed. With this in mind, phage therapy presents an extremely necessary and promising alternative to antibiotics.
How Phage Therapy Works
The two primary categories of phages are lytic and lysogenic phages. Lytic phages directly and quickly kill bacterial cells, while lysogenic cells are less effective in part due to their delayed lysis. Lytic phages have a more immediate lysis compared to lysogenic phages. Furthermore, because lysogenic phages can integrate into their host’s genome, there is also a risk of gene transfer, which could spread an antibiotic resistance gene. With this in mind, lytic phages are typically used in phage therapy due to their direct and rapid action as well as the reduced risk of gene transfer. Researchers look for phage in places where bacteria grow, such as hospital sewage. Phages can be cataloged into a phage bank once they are identified and characterized. Next, the phage must be grown in bacteria and filtered into a phage stock. Phages will inject viral DNA into the host, causing the bacterium to produce more phages. These phages then infect and kill other bacteria which results in cell lysis. This process is depicted in the image below. Phage therapy typically uses administrations of phages orally, topically, or intravenously to clear a bacterial infection.
Gaining FDA Approval
Currently, gaining FDA approval for phage therapy boils down to one thing: research. To develop more treatment opportunities for phage therapy, clinical trials must be conducted to demonstrate the efficacy of phage therapy. Once the treatment is proven beneficial through clinical trials, the FDA can make progress towards approving phage therapy in a clinical setting. Research on phage therapy is relatively new to the medical field, so FDA approval has not been granted in the clinical setting. The Food and Drug Administration (FDA) requires new drugs or treatments to be thoroughly tested in clinical trials in order to grant approval. However, in emergent circumstances, the expanded access pathway can be used to gain emergency approval from the FDA. Expanded access, sometimes called “compassionate use,” is the use of an unapproved drug or treatment for a patient when there are no alternative therapy options available. As a patient or interested individual, your support as well as donations towards phage therapy research can make an extreme impact on gaining FDA approval. Once the FDA grants approval, millions of patients can be saved.