(Vienna, 30 June 2026) Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a chronic, severely debilitating multisystemic condition that is estimated to affect up to 70 million people worldwide. The fact that only clinical criteria have been used for diagnosis to date further exacerbates the situation for those affected. As part of the international research project "DISCOVER-ME", led by MedUni Vienna, the aim is now to lay the foundations for improved diagnostics tailored to patient subgroups and for the development of targeted treatment strategies. The project is funded by the EU under the "Horizon Europe" programme with over 7.5 million euros; results are expected over the next four years.
ME/CFS is a complex multisystemic disorder that affects, among other things, the immune, nervous and endocrine systems, as well as energy metabolism. A characteristic feature of the condition is so-called Post-Exertional Malaise (PEM): a marked, often delayed worsening of symptoms or the onset of new symptoms following physical or mental exertion. Diagnosis is currently based exclusively on clinical criteria; other causes for individual symptoms must first be carefully ruled out.
This costs valuable time: according to research data from the Medical University of Vienna, it takes an average of five years to reach a diagnosis in Austria, Germany and Switzerland. A study of the Angers University hospital showed that with every month of delay, the likelihood of clinical improvement decreases. Objective laboratory parameters or validated biomarkers – i.e. measurable biological markers of the condition to speed up diagnosis – do not yet exist.
More than 60 per cent unable to work
The actual prevalence of ME/CFS is likely to be significantly higher than previously assumed. According to estimates, up to 70 million people worldwide are affected. "More than 60 per cent of patients are unable to work, and around 20 per cent are so severely affected by the condition that they are confined to their homes or beds. The annual socio-economic costs in Europe are estimated at around 40 billion euros, with data collected following the SARS-CoV-2 pandemic suggesting that these costs are rising," reports Eva Untersmayr-Elsenhuber (Center for Pathophysiology, Infectiology and Immunology at MedUni Vienna), who coordinates the international "DISCOVER-ME" project. Untersmayr-Elsenhuber is also one of the two directors of the National Reference Centre for Post-Viral Syndromes, which was awarded to MedUni Vienna in 2024 by the Federal Ministry of Labour, Social Affairs, Health, Care and Consumer Protection.
Comprehensive analyses planned
DISCOVER-ME follows an integrative, multi-stage research approach. In a first step, 2,000 data sets will be collected using a refined, validated questionnaire to identify different clinical presentations of ME/CFS. Subsequently, a comprehensive biological characterisation based on patient samples from several independent European biobanks is planned. The study will include samples from more than 700 ME/CFS patients and nearly 200 control subjects.
The study will investigate changes in the immune system, metabolism, hormonal balance and mitochondrial function. Mitochondria are the "powerhouses" of cells and play a central role in energy production. In addition, modern multi-omics methods will be employed. These involve the parallel analysis of large molecular datasets, such as those derived from epigenetic patterns or proteins (proteomics). The aim is to identify reproducible biomarkers and to classify ME/CFS into clinically relevant subtypes based on biological mechanisms.
The data obtained is integrated into a newly developed, computer-assisted disease map. On this basis, so-called in silico models – that is, simulations of biological processes – as well as patient-specific "digital twins" are created. These models make it possible to test potential therapeutic approaches virtually and to select promising active substances in a targeted manner. As part of a so-called systematic drug repurposing approach, more than 9,000 already known active substances are being investigated using computer simulations. The aim is to select 20 to 50 particularly promising drugs from these, which are to be researched further in subsequent projects.
"With DISCOVER-ME, we aim to systematically map the biological basis of the disease and translate this into a clinically applicable concept," says Eva Untersmayr-Elsenhuber. "Our goal is to be able to offer patients a confirmed diagnosis at an earlier stage in future, along with treatment options tailored to their individual disease mechanisms."
Leading research institutions involved
The consortium involved in the project brings together leading European and international research institutions, including Imperial College London, Uppsala University, the University of Galway and the Centre national de la recherche scientifique (CNRS), as well as several biobanks in Europe specialising in ME/CFS. DISCOVER-ME is part of the EU’s Horizon Europe framework programme under the theme "Tackling high-burden for patients and under-researched medical conditions" and is scheduled to run for four years.