Rare Disease Day 2026

February 28, 2026

Each year, on the occasion of Rare Disease Day (RDD), our medical writing team reaffirms its support for the patients, caregivers, and healthcare professionals committed to this field.

Internationally, this annual campaign is coordinated by EURORDIS-Rare Diseases Europe. Campaign materials are available in multiple languages on the dedicated Rare Disease Day® website to encourage RDD participation and raise awareness of rare diseases among the general public and decision-makers.

Some figures on rare diseases

About 300 million people are living with a rare disease worldwide, representing 5% of the global population — the equivalent of the population of the world’s third-largest country.

Although each rare disease affects only a small number of patients (fewer than 5 in 10,000 according to the European definition), rare diseases are numerous (more than 6,000 have been identified to date), and their clinical presentations are often so complex that patients often endure years of diagnostic wandering.

In France, according to figures from Alliance maladies rares — an umbrella organization that brings together 240 associations of people living with rare diseases — 5 years are required for 25% of the more than 3 million French people affected by a rare disease to obtain an accurate diagnosis. Diagnosis is a key step in patient management, especially when treatments exist that may improve patient quality of life. Indeed, although 95% of rare diseases currently have no curative treatment, multidisciplinary care can be implemented to manage some symptoms while research continues to advance.

Santé Active Edition ─ Synergy Pharm and rare diseases en 2026

Our experienced medical and scientific writing team, with a growing expertise in rare diseases, has contributed to several projects in this field in recent months. Rare Disease Day provides an opportunity to shine a spotlight on these conditions and on the scientific and medical advances supporting their diagnosis and management.

Fabry disease

Fabry disease is a rare genetic disorder caused by pathogenic variants of the GLA gene, which encodes the enzyme alpha‑galactosidase A. Fabry disease is systemic, progressive, and can be fatal. Its transmission is linked to the X chromosome, resulting in a variable phenotype, especially in women, and a complex clinical picture. Depending on the pathogenic variant involved, early treatment can slow down the progression of symptoms.

We are proud to have participated in the writing and publication of a literature review showing how different artificial intelligence (AI) methods can improve diagnosis, guide treatment decisions, and support follow-up for patients with Fabry disease: Applying artificial intelligence to rare diseases: a literature review highlighting lessons from Fabry disease (Orphanet Journal of Rare Diseases, 2025). Indeed, AI has seen remarkable growth in recent years, particularly in the field of rare diseases. Machine-learning and deep-learning methods, which allow the classification and analysis of large datasets, are valuable approaches for improving the diagnosis of rare diseases, for example, by helping to identify patients likely affected by a rare disease within a large population or by analyzing patient electronic health records to support diagnostic decisions. The authors of this narrative review also discuss the ethical considerations that accompany emerging AI-based approaches.

Rare neuromuscular diseases

Rare neuromuscular diseases (RNMDs) are a genetically and clinically diverse group of disorders that pose major challenges for timely diagnosis and effective management. In line with one of the aims of the third French National Plan for Rare Diseases (PNMR3), the FILNEMUS network has been working to identify factors associated with a higher risk of diagnostic wandering and diagnostic impasse among patients with RNMDs in France in order to accelerate diagnosis and thereby improve patient management.

Our medical writing team supported experts from FILNEMUS network centers and the French National Rare Disease Registry (BNDMR) in drafting an article that provides a detailed comparative analysis of the socioeconomic and demographic characteristics of around 30,000 patients with and without a confirmed RNMD diagnosis being managed by a FILMENUS network center: Diagnostic Impasse and Wandering in Patients With Rare Neuromuscular Diseases: Insights Into Patient Characteristics From the French National Network for Rare Neuromuscular Diseases (FILNEMUS) and the French National Rare Disease Database (BNDMR) (European Journal of Neurology, 2025).

The results of this study provided the most accurate estimate to date of the proportion of French RNMD patients in a state of diagnostic wandering or impasse (13.5%). Moreover, they demonstrated the feasibility of creating a high-quality registry of undiagnosed patients across a national network of rare disease expert centers thanks to information collected through a network‐wide, standardized, and quality‐controlled process. It also identified eight RNMDs positively associated with the lack of a confirmed diagnosis, and highlighted the need for better training of general practitioners and local hospital neurologists, more rapid referral, and access to expert centers. The results also stressed the need for improvement to diagnostic services to help promote and maintain patient engagement in the diagnostic process, particularly for diseases with a later-age of onset, acquired diseases, and those associated with complex diagnostic pathways.

Cystic fibrosis

Classified as a rare disease, cystic fibrosis is one of the most common genetic disorders in the European population, with an estimated incidence of 1 in 4,500–6,000 births. Systematic newborn screening (NBS) was introduced in France in 2002 and allows the early diagnosis of approximately 150 infants each year, enabling timely management before the onset of severe symptoms. Despite the progressive course of the disease, medical treatments — combined with respiratory physiotherapy, aerosol therapy, pancreatic enzyme supplements, as well as appropriate physical activity and nutritional management — significantly improve lung function and patient quality of life. In recent years, new targeted therapies have played a key role in transforming the disease course and increasing life expectancy, which now ranges between 40 and 50 years for many patients.

Our team recently participated in the drafting of the scientific rationale for the National Diagnosis and Care Protocol (PNDS) for cystic fibrosis, which has been updated by members of the Muco-CFTR rare disease network, other experts in the field, and members of the Vaincre la Mucoviscidose patient association. These documents aim to harmonize clinical practice and ensure optimal patient care throughout the country and across all French territories. The French PNDS for cystic fibrosis was published in December 2025 on the Haute Autorité de Santé (HAS) website: https://www.has-sante.fr/jcms/c_2792719/fr/mucoviscidose.

Read our previous news articles to find out more about cystic fibrosis (Rare Disease Day 2023; “Virades de l’espoir” 2022: Walks of hope in France to help in the fight against cystic fibrosis; Rare Disease Day 2022) and newborn screening (Fifth International Newborn Screening Day; First International Neonatal Screening Day).

Epidermolysis bullosa

Epidermolysis bullosa (EB) is a rare genetic disease characterized by extreme fragility of the skin and mucous membranes. Recessive dystrophic epidermolysis bullosa (RDEB), caused by mutations in the COL7A1 gene leading to collagen VII deficiency, is one of the most severe subtypes of EB. Despite conventional symptomatic treatments (emollients, topical corticosteroids and analgesics), children with RDEB often experience pruritus and severe chronic pain, which significantly impair wound healing, sleep and quality of life.

A prospective pilot study, conducted in a pediatric reference center for EB in France, evaluated the efficacy of an oral solution of cannabidiol (CBD) — whose analgesic and anti-inflammatory properties have been demonstrated in various clinical contexts — on pruritus, chronic and acute pain, sleep, and quality of life, as well as its tolerance (adverse effects, liver function and plasma CBD concentrations), in 10 children (aged 2 to 17 years) with RDEB and chronic pruritus inadequately controlled by conventional treatments (study No. NCT05651607). Our team were delighted to support authors with the editing of the article and the preparation of the responses to reviewers: Therapeutic efficacy of cannabidiol on pruritus and pain in children with recessive dystrophic epidermolysis bullosa: a pilot study (The British journal of dermatology, 2026).

Find out more about epidermolysis bullosa in our previous news articles: Rare Disease Day 2023 and Rare Disease Day 2022.

Metastatic uveal melanoma (MUM): a rare cancer

Rare disease awareness also includes rare cancers, which affect fewer than 6 people per 100,000 each year worldwide. Figures shared by EURORDIS on the Rare Disease Day® website also indicate that 1 in 5 cancers is rare, and that the 5-year survival rate is lower for rare cancers than for more common ones.

Metastatic uveal melanoma (MUM) is a rare eye cancer with a persistently poor prognosis. Although it accounts for only a small proportion of melanomas, MUM remains a major challenge in oncology. Indeed, metastasis occurs in 20 to 30% of patients, often involving the liver, and resulting in a particularly unfavorable prognosis. Although scientific knowledge is growing, several challenges remain: treatment options are still limited for some patients despite therapeutic advances, and more structured care pathways are needed for patients.

Our team recently participated in the drafting of French guidelines for the management of MUM based on a consensus meeting bringing together experts in medical oncology, radiology, oncodermatology, and liver surgery: Management of metastatic uveal melanoma: French expert consensus guidelines (Bulletin du Cancer, 2025). At time when research and innovation remain crucial for patients with MUM, this publication provides an update on clinical and biological knowledge of the disease, recent therapeutic advances, and perspectives for patient management in France.