Phage Therapy
Nature’s Secret Weapon For The Fight Against Superbugs
A. J. Li
CHANCES ARE, YOU HAVE USED ANTIBIOTICS BEFORE. Perhaps they have even saved your life. It is no exaggeration to say antibiotics are a cornerstone of modern medicine that has saved millions of lives since the discovery of Penicillin in 1928. But antibiotic resistance has been an insidious problem for decades, caused by ignorant overuse of these miracle drugs. Is the curtain now falling on a near 100-year era of antibiotics? Enter the bacteriophage.
Bacteriophages, or more simply, phages, are tiny viruses that infect bacteria. Ranging from 24-200 nanometres in length, there are estimated to be more than 1031 of them, more than every other organism on Earth, combined. They attack their target bacteria by attaching to them and then injecting their genetic material into them, essentially hijacking the bacteria and turning it into a phage machine, forcing it to produce more phages until the bacteria bursts. Think of a balloon popping after too much air is blown in. These newly created phages then spread upon being released from within the now dead bacteria and infect other bacteria, continuing the cycle.
Phages are no new discovery. Their discovery dates back to the early 20th century, around 1915, before the discovery of antibiotics. In fact, at one point in history, phages were on course to be the revolutionary treatment for bacterial infections! It turned out to be the advent of antibiotics that overshadowed ongoing phage research, leading to its decline in the Western medical world. Meanwhile, states of the Soviet Union such as Russia continued to research and utilise phage therapy, preserving its potential efficacy. It is only with the grave dangers posed by antibiotic resistant bacteria that phage therapy has seen a renaissance as modern-day researchers search for novel solutions.
So what makes them so special compared to antibiotics? Phages are extremely selective in their targets. One type of phage only attacks a specific strain of bacteria, minimising collateral damage to the “good” bacteria within the body, something antibiotics are unable to do. Furthermore, they overcome bacterial mutations which cause antibiotic resistance by evolving alongside them, counteracting new bacterial defence mechanisms with their own new weapons. This dynamic interaction between phages and bacteria gives rise to a potentially sustainable treatment strategy, labelled “phage therapy” in a world beyond antibiotics.
However, one of the greatest strengths of phages is also one of its weaknesses in being integrated into mainstream medicine. Its specificity of target bacteria often means that phages are usually administered in “cocktails” during phage therapy. A selection of different types of phages are mixed together and this medicinal melange is served to the patient in the hope that one of the administered phages is effective at attacking the target bacteria. While this is not necessarily a problem during treatment, it requires a lot of time to develop such a precise cocktail for application, further exacerbated by current regulatory hurdles. For context, it takes a regular drug on average 10.5 years to complete clinical trials and progress to regulatory approval. Phage therapy treatments could take even longer. There is some hope though, recent technological advancements such as high-throughput sequencing and bioinformatics, have accelerated the identification of potent phages, streamlining the process of designing tailored treatments.
This does not mean phage therapy is not already being used however. As previously mentioned, many Eastern European countries continued phage research after it was all but dropped by the Western world, and it is a routine medical practice in countries such as Georgia, Poland, and Russia. In the Western world, phage therapy has also been used as a last resort treatment for otherwise untreatable cases involving antibiotic resistant bacteria. Notably, it has been used several times for patients suffering from MRSA (Methicillin resistant staphylococcus aureus). It does not take much to find a “miracle” case online of people using phage therapy against a life-threatening infection from one of the many strains of antibiotic resistant bacteria after having been told they have days to live.
Phage therapy also does not necessitate the complete phasing out of antibiotics. In fact, research has shown that in order for bacteria to develop some sort of resistance against phages, it has to shed its antibiotic resistance. This almost guarantees that humanity will have an effective treatment against even the most dangerous bacteria by using classic antibiotic treatment in tandem with phage therapy.
The future of phage therapy is certainly bright. It is also not an eternity away. Indeed, clinical trials and discussions around its regulation are already underway. Perhaps one day, we will no longer go to the pharmacist and ask for a course of antibiotics. Perhaps instead, we will be asking for a cocktail of phages.
