Bacteriophage or ‘phage’ is a virus that selectively attacks bacteria. Phage therapy was used for centuries to treat bacterial infections, but was largely replaced when antibiotics became widely available.

Researchers are now revisiting the use of phage therapy to treat bacterial infections that are growing increasingly resistant to current antibiotic treatments.

Lead researcher of the study, Professor Jon Iredell from The Westmead Institute for Medical Research (WIMR) said, “Antibiotic resistance is a rapidly emerging threat to global health. Because of this, phage therapy is experiencing a renaissance.

“We know that phage therapy has the potential to treat infections, but evidence of its safety and effectiveness, particularly from clinical trials, is currently limited.

“Our study investigated whether phage therapy is safe in treating severe Staphylococcus aureus bacteraemia.”

Staphylococcus aureus bacteraemia occurs when bacteria enters the bloodstream. This can lead to life threatening conditions, including infective endocarditis (an infection of the heart) and sepsis (a severe immune response to infection).

The research team administered phage therapy intravenously to 13 patients with severe Staphylococcus aureus infections. The patients also received treatment with antibiotics at the same time.

Professor Iredell said, “Our patients did not show any signs of adverse reaction from the phage therapy.
“Importantly, our phage was produced under Goods Manufacturing Practices (GMP), which ensure the quality of therapeutic products.

“This is the first time that research has been able to show that IV-administered phage therapy, produced under GMP conditions is safe and well-tolerated in people with severe Staphylococcus aureus infections.”
Rates of antibiotic resistance are increasing worldwide, making it harder to treat common infections, such as urinary tract infections, and certain sexually transmissible infections.

“If we can’t combat this threat, we may reach a point where infections that were previously simple to treat will become untreatable,” Professor Iredell said.

“Antibiotic resistance is a huge threat to our health system – we wouldn’t be able to perform certain life-saving treatments, such as transplantation and cancer therapy, without effective treatment against infections.

“More evidence in support of phage is still needed before it’s offered to patients on a larger scale.
“However, our study makes it clear that it could, potentially, offer a safe treatment for serious infections, and help reduce the impact of antibiotic resistance,” he concluded.

The research was published in Nature Microbiology.