Dr Ana Rath
UNIT director, INSERM, US14 – Orphanet
The Orphanet knowledge base maps the research landscape in rare diseases, providing important insight into trends in therapy development when coupled with curated disease-gene relationships.
“Although most rare diseases we record are genetic in origin, and a large proportion have an identified causative gene, we observe that only a minority are currently represented in the gene therapy development pipeline,” explains Dr Ana Rath, Unit Director at the French Institute of Health and Medical Research, Orphanet’s host institution. “This trend is particularly observed at the stage of market-authorised therapies.”
Our data can help identify the gaps and the sticking points in the pipeline
Data demonstrates significant unmet needs
Indeed, an analysis in 2026 of the Orphanet database has demonstrated that gene therapy development has been driven by a relatively limited number of disorders that attract clinical investment. Although disorders with multiple causative genes are actively explored during early research projects, therapeutic translation appears to be more successful for disorders with a single causative gene.
“The gene therapy landscape is highly concentrated at the moment,” explains Dr Rath. “This reflects the progression of only a subset of rare diseases through the development pipeline.” Only 56 of around 6,500 rare diseases in Orphanet’s nomenclature of rare diseases are associated with an approved gene therapy (GT) at this time.1,2 Rare neoplastic diseases account for the largest share of diseases with approved gene therapies, likely reflecting the major role of oncology in the development and clinical implementation of gene therapies, notably CAR-T cell therapies.
Untapped potential for future innovations
“Overall, the limited number of approved GTs compared with preclinical projects and clinical trials highlights both the challenges of therapeutic translation and the considerable potential for future growth in the field,” comments Dr Rath. “Our data can help identify the gaps and the sticking points in the pipeline, where targeted efforts could be made in the future to help deliver more opportunities for the over 300 million people living with a rare disease across the world.2”
Find out more: orpha.net
[1] De Carvalho, M. et al. (2026). Tracing the path from gene discovery to gene therapy possibilities in rare diseases: an Orphanet-based analysis.
[2] Lucano, C. et al. (2026) The Orphanet Nomenclature and Classification of Rare Diseases for Improved Patient Recognition and Data Interoperability: Qualitative and Quantitative Analysis. https://medinform.jmir.org/2026/1/e84553.
[3] Wakap, S.N. et al. (2019). Estimating cumulative point prevalence of rare diseases: analysis of the Orphanet database. https://tinyurl.com/mcfc3ecz.
