Antibiotics have revolutionized modern medicine. But increasingly, they no longer work. Bacteria are developing resistance, and infections that were once easy to treat are becoming life-threatening diseases. Many people in Switzerland also suffer from chronic antibiotic-resistant infections. In some cases, only an experimental approach can help: phage therapy. Although this approach has existed for several decades, it is now set to receive renewed attention. Public events in Switzerland aim to bring together scientific findings, patient experiences, and political perspectives.
What are bacteriophages?
Bacteriophages, or phages for short, are viruses that specifically attack bacteria. They attach to the surface of a bacterium, infect it with their genetic material, and cause it to produce new phages. The bacterium becomes overloaded and bursts. Because phages are highly specific, they are interesting for use in antibiotic therapy. They only infect and destroy the bacterial strains they are directed against, leaving the other beneficial bacteria in the body undisturbed.
Phages as antibiotic alternatives?
Phages are considered a great hope, especially in the fight against multidrug-resistant pathogens. They take over when even the strongest antibiotics fail. A major advantage is also their adaptability. When bacteria become resistant, phages can also be further developed or newly combined. Modern genetic engineering allows phages to be specifically modified to increase their effectiveness or expand their host range. Researchers use methods such as the CRISPR-Cas gene scissors to adapt phages so that they can efficiently attack resistant bacterial strains. Such genetically optimized phages are considered a promising approach to further improve treatment options for multidrug-resistant infections.
IIn Switzerland, teams at ETH Zürich, the Universität Lausanne, as well as within the Zurich research initiatives "The Loop Zurich" and "ImmunoPhage" are researching phages that work against specific pathogens. The narrow spectrum of action of phages and the physically limited space to accommodate new genes in the phage shell represent the challenges that researchers must address. Since these are viruses intended for use as medicine in humans, another hurdle is their approval, which must be tackled together with the authorities.
Approval in Switzerland and international comparison
Officially, phage therapy is not approved in Switzerland. It may only be used in exceptional cases and under strict conditions imposed by Swissmedic, usually as a so-called compassionate use treatment. Since phages are "living," i.e., biologically active viruses and not medicines in the classical sense, they do not fit into any existing approval category. This means that patients who could be treated in other countries often have no chance of receiving phage therapy in Switzerland. Experts are therefore calling for clear rules and more flexibility to better help those affected.
Belgium has already created a legal framework that permits phage treatments. Since 2018, pharmacies there have been allowed to produce and use personalized phage therapies. France and Germany are also conducting clinical trials and examining new approval pathways. The USA is pursuing similar approaches with individual special authorizations. This has enabled infections that no longer responded to antibiotics to be contained within a few days in many cases. These international experiences show that phage therapies can be applied safely and effectively when regulations are adapted.
Research, politics, and the public in dialogue
In Switzerland, the "Phage Therapy Forum" project is supported by the Agora Program of the Swiss National Science Foundation and the Forum for Genetic Research of SCNAT. The first of two public events on phage therapy as an antibiotic alternative will take place in Basel on January 31, 2026. This will be followed by a second event on February 14, 2026, in Lenzburg. Participants include experts from medicine and research, representatives from Swissmedic, patients, and National Councillor Christian Lohr. The discussion will focus on how Switzerland can improve access to phage therapies while ensuring safety and quality. (Register here)
Sources
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