Rare Disease Day 2026: Discover Horizon Europe projects advancing research and innovation for rare diseases

Rare diseases affect over 300 million people worldwide, yet only 6% currently have an approved treatment option. To address this challenge, projects funded under the Horizon Europe ‘Health’ programme conduct research to develop much-needed treatments. 

Turning cutting-edge science into tangible benefits 

The European Rare Diseases Research Alliance (ERDERA) is a Horizon Europe partnership uniting more than 170 public and private organisations across 37 countries, focused on improving prevention, diagnosis and treatment for the 30 million Europeans living with a rare disease. 

Just one year into implementation, the seven integrated service areas that are part of the project are fully operational and are working to move rare disease research further. 

Key achievements include: 

• Launch of the first Joint Transnational Call (JTC 2025):
  • 18 multinational preclinical therapy projects selected from 161 proposals,
  • Backed by 29 national and regional funders across 23 countries,
  • €29 million in combined funding;
• Launch of a second JTC 2026, focused on resolving unsolved rare genetic and non-genetic disease cases;
• Support to an operational Clinical Research Network:
  • Harmonising data and research pipelines across Europe,
  • Collecting and harmonising 10,000 unsolved rare disease diagnostic datasets,
  • Establishing legal and governance frameworks for secure cross-border data sharing. 

Together, these milestones position ERDERA as a key driver of coordinated European action on rare diseases, accelerating research, strengthening collaboration and laying the groundwork for faster diagnosis and future therapies. 

Closer collaboration between European Reference Networks 

The European Rare Disease Research Coordination and Support Action consortium (ERICA), in which all 24 European Reference Networks (ERNs) took part, has built on the strengths of the individual ERNs and created a platform that integrates all ERNs’ research and innovation capacities. ERNs are secure networks involving reference centres, highly specialised laboratories and institutions, enabling specialist across Europe to consult each other. 

ERICA has focused on knowledge-sharing, engagement with stakeholders in the rare disease domain and assembly of transdisciplinary research groups working across the global health spectrum. This has allowed the project to reach effective data collection strategy, better involvement of patients and higher quality and impact of clinical trials.  

This will result in efficient access and safe therapies for the benefit of patients suffering from rare diseases and complex conditions. 

Towards personalised therapies for ultra-rare CFTR mutations 

The HIT-CF project has worked to ensure that people with ultra-rare cystic fibrosis (CF) mutations are not left behind in the development of new treatments. To achieve this, drug candidates of several companies were first tested in the laboratory on patient-derived mini-intestines (organoids).  

In a second step, based on the reaction in the organoids, a smaller group of patients were assigned to studies (clinical trials) with one of the drug candidates. These trials successfully demonstrated a clear relationship between lab results and clinical results. Patients whose organoids responded well to the compound were also responsive in the clinic, confirming the success of the biomarker selected and showing that the new drugs could be effective.  

The project concluded in June 2025, but the consortium continues its work by discussing screening and treatment approvals with regulatory bodies such as the European Medicines Agency. Moreover, the FAIR Therapeutics company for biotechnology research was found to further advance HIT-CF'S achievement, abiding to fair medicine principles. 

Drug repurposing with artificial intelligence (AI) for muscular disorders 

The DREAMS project uses AI to develop novel therapies capable of treating multiple rare neuromuscular disorders presently without a cure. More specifically, the project focuses on identifying shared pathological phenotypes, which are common characteristics or traits that can be observed across different diseases. By targeting these shared features, scientists hope to develop treatments that potentially will benefit multiple diseases at the same time. 

The project will also set up new clinical trial designs and develop the first platform for drug discovery using AI and induced pluripotent stem cells (iPSC) to identify safe and effective treatments. 

The project’s key scientific publications include: 

• Basket trials in rare diseases: a systematic review of current practices, methodological challenges, and future directions;
• DREAMS: Drug REpurposing with Artificial Intelligence for Muscular Disorder;
• A third publication identifying common markers across multiple muscular disorders will be published in the JCI Insight Journal at the end of March 2026. 

Background 

Horizon Europe is the research and innovation programme of the EU for the period 2021-2027. The aims of Cluster 1 ‘Health’ include improving and protecting the health and well-being of citizens of all ages by generating new knowledge, developing innovative solutions and integrating where relevant a gender perspective to prevent, diagnose, monitor, treat and cure diseases.