Rare Disease Day 2026: Rounding up the latest advancements in research and treatment

About 300 million people around the world—and around 1 in 10 U.S. citizens—live with a rare disease. Representing over 7,000 various disorders and conditions, the impact of rare diseases extends even beyond the patients themselves to their families, caregivers, medical teams, and communities.

On Rare Disease Day, we join the global community in raising awareness around rare diseases and promoting social and healthcare equity for the people living with these conditions. Lack of scientific understanding and public awareness both contribute to challenges for patients and their providers.

In the year since Rare Disease Day 2025, the scientific community has made promising advancements in both the process of drug discovery as well as the treatment of rare conditions like muscular dystrophy, cystic fibrosis, and Rett syndrome.

Let’s take a look at some of the most noteworthy updates in rare disease research and treatment.

New FDA approval process aims to accelerate gene therapy development

In September 2025, the U.S. Food and Drug Administration (FDA) introduced the Rare Disease Evidence Principles (RDEP), a new approval process intended to accelerate and improve the review of genetic therapies targeting rare diseases.

With significantly smaller patient bases to pull from compared to more common diseases, recruiting for and conducting trials for rare disease drugs can be a challenge. A 2022 study from the Tufts Center for the Study of Drug Development found that Phase II and III rare disease clinical trials had significantly longer start-up timelines, required longer treatments, and achieved lower completion rates than trials for non-rare diseases.

Developed by the Center for Drug Evaluation and Research and the Center for Biologics Evaluation and Research, the RDEP attempts to alleviate this issue by allowing rare disease drug developers to seek approval based on the completion of a single clinical trial, supplemented with “robust confirmatory evidence.” This evidence can include biomarkers, relevant non-clinical models, pharmacodynamic data, case studies, and other data.

The FDA notes that drugs being approved through the new process may come under additional scrutiny from the agency post-commercialization to ensure safety and efficacy.

While the RDEP effectively broadens the clinical trial pipeline for rare disease drug development, last year’s cuts to FDA funding and the layoffs of more than 3,500 full-time positions could still present a bottleneck in the approval process.

AI and genomics boost rare disease discovery

Artificial intelligence and machine learning (AI/ML) are fast becoming standard technologies in the world of medicine, with applications in imaging processing, charting, administration, and more. These technologies are increasingly prevalent in drug development, too, where they’re enabling faster discoveries of novel molecules and compounds used to treat a variety of conditions, including rare diseases.

In January 2026, the Google DeepMind team launched AlphaGenome, a DNA sequencing model that helps researchers identify regulatory genetic mutations across the entire genome rather than just within protein-coding regions. This allows researchers to rapidly predict and score the impact of genomic variations across modalities like gene expression, transcription initiation, and chromatin accessibility, according to a study published in Nature.

Put more simply, the AlphaGenome AI could accelerate the discovery of genes associated with rare diseases—and thus the mechanisms by which they might be treated—by identifying and modeling precisely where errors in genetic code occur. Spinal muscular atrophy, certain kinds of cystic fibrosis, and other rare genetic disorders can be caused by these errors.

In the summer of 2025, a research team at the Wyss Institute at Harvard University used AI to identify a novel treatment pathway for Rett syndrome, a mutation of a gene on the X chromosome that causes cognitive and physical impairments, primarily in girls. Using the nemoCAD modeling system, the team found that the drug vorinostat—approved by the FDA to treat cutaneous T-cell lymphoma—was more effective at modifying the effects of Rett syndrome than trofinetide, the disease’s heretofore solely approved treatment.

Groundbreaking firsts in the treatment of muscular dystrophy

Muscular dystrophy (MD) comes in dozens of varieties with varying symptoms, prognoses, and areas of impact. Caused by mutations in the genes responsible for muscle development and function, different forms of MD manifest at different ages and in different parts of the body, but all forms tend to ultimately lead to failure of critical organs like the heart and lungs.

The most effective MD treatments to date involve the administration of genetic therapies to newborns to modify the genes related to spinal muscular atrophy. But in 2021, researchers made the groundbreaking decision to treat a fetus for MD while still in the womb.

In early 2025, those researchers published the results of their study, revealing that the patient had grown into a healthy two-and-a-half-year-old girl with no signs of the disease. While the child continues to take the gene-targeting drug, her current condition could give hope to would-be parents concerned about passing on the disease.

The release of the study coincides with the FDA’s decision to lift a two-year hold on Entrada Therapeutics’ MD candidate drug. With the go-ahead from the federal government, Entrada can now test the drug on patients with MD in the U.S. (it had previously studied the drug’s impact on healthy patients in the UK).

Already, 2026 is showing progress for the treatment of Duchenne muscular dystrophy, as the phase III EMBARK study delivers three years of data demonstrating the efficacy of delandistrogene moxeparvovec (brand name Elevidys) in improving motor function among boys aged four to seven years.

Gene and cell therapy breakthroughs in cystic fibrosis

Cystic fibrosis (CF) is a genetic disease that causes mucus in the body to become thick and sticky, leading to inflammation, infections, and other issues in the lungs, pancreas, and other organs. For the over 100,000 people living with cystic fibrosis worldwide, managing the disease often requires a daily regimen of airway clearance, inhaled medication, and various other therapies.

The last decade saw the rise of new medications that modulate the cystic fibrosis transmembrane regulator (CFTR) gene, helping certain patients regain near-normal lung function and life expectancy.

In 2025, a study from Case Western University found that melatonin treatment improved bacterial clearance and inflammation in mice with CF. Plus, Dartmouth researchers learned that cystic fibrosis impacts the gut microbiomes of infants, suggesting that probiotics or dietary interventions could mitigate the effects of the disease.

Later that year, researchers from Oregon State University, Oregon Health & Science University, and the University of Helsinki discovered a new type of nanoparticle that can directly deliver genetic therapy to lung cells. The treatment shows promise both for the improvement of lung function related to cystic fibrosis, as well as for slowing the growth of lung cancer cells.

More recently, phase I trials have identified two novel gene therapies for CF: KB407, a treatment enabling the healthy expression of CFTR proteins in the lungs of patients not otherwise eligible for CFTR modulator therapies, and 4D-710, which heads into phase II trials with an early record of improving lung clearance and overall quality of life for CF patients.

Find the providers, therapies, and patients involved in rare disease treatment

The latest advancements in rare disease research and treatment highlight some incredible progress. From gene therapies to repurposed drugs to alternative treatment pathways, the medical and scientific community has come a long way in addressing rare diseases—even since the first Rare Disease Day was observed in 2008.

Whether you’re interested in helping providers bridge the knowledge gap in rare diseases, want to find the physicians responsible for treating specific patient cohorts, or need to understand how rare disease impacts your market, Definitive Healthcare can help.

Our healthcare data and analytics solutions help you navigate the healthcare landscape, make more effective strategic decisions, and seize the most impactful opportunities. Sign up for a free trial today to learn more.