Method for testing combinations of antibiotics awarded EU funds

A new method that evaluates how effective different combinations of antibiotics are against resistant bacteria is to be tested at several universities in Europe, including Karolinska Institutet. Christian Giske, a researcher at the Department of Laboratory Medicine, is Academic Lead for the EU-funded study, which will last for at least two years.

Antibiotic resistance is a major global problem. In Europe, more and more patients develop sepsis caused by intestinal bacteria and which is very difficult to treat.

“In Sweden, too, we come across bacteria that are very difficult to treat. We try to overcome this by using combination treatment; in other words, we give more than one antibiotic at the same time. The problem is that two preparations can sometimes affect each other negatively and cause side effects,” says Christian Giske.

Now he is to collaborate with researchers at universities in a number of EU countries to test a new and rapid analysis method for demonstrating which antibiotic combinations are effective.

Kill a given bacteria

“It is important to know whether two preparations actually work or not. At the moment, when faced with an infection we have to guess how the preparations could work together. There are methods that evaluate whether several preparations together can kill a given bacteria, but these methods are time-consuming and you have to have access to research animals. The new method involves measuring the energy production in the bacteria to determine whether they are alive or dead. We expect that this new method will enable us to more quickly and more accurately predict whether the preparations will work,” he comments.

The analysis method and associated test equipment to be tested have been produced by company Symcel which, together with the researchers, has received a total of EUR 3.6 million from Horizon 2020, an EU-financed research and innovation program. As well as Karolinska Institutet, universities in Denmark, Italy and Spain will also be taking part.

“Together we have access to a variety of bacteria collections. We need a broad collection if we are to determine how robust the analysis method is. The laboratory in Denmark will focus on animal studies in mice which will act as a reference,” Dr Giske says.

Patients with severe infections

The researchers will test not only how different types of antibiotics act two and two, but also in combinations of three antibiotics. They will also test antibiotics singly. Just four to eight hours’ analysis will answer whether the tested antibiotic combination is effective or not.

“We will choose preparations that we normally use to treat patients. We will simulate what happens in patients with severe infections such as sepsis, even though the model is not specific for sepsis,” he comments.

If the method turns out to be effective, it will benefit the thousands of patients in Europe who are affected by resistant bacteria every year. The hope is that the analysis method, if it is effective and robust, can be applied in practice at the major hospitals in Europe and other parts of the world.

Text: Maja Lundbäck (in translation from Swedish)