A new report from the Tufts Center for the Study of Drug Development finds that it takes 2.3 years, or 18 percent, longer to develop an orphan drug compared with medicines to treat more common conditions.
Although clinical trials for orphan diseases – defined as affecting fewer than 200,000 people in the U.S. – tend to be smaller than other studies and orphan drugs often qualify for expedited review pathways, the reality is that development of these medicines poses many unique challenges in addition to the usual high hurdles of drug development. According to Tufts, the most common challenges include:
- Variability of disease: The most commonly cited challenge was variability of disease. Diversity of symptoms, severity and other aspects of the disease can make it difficult to evaluate patients’ response to a treatment.
- Geographically dispersed populations: Another common issue faced by companies is that patients are not just few but they are far between. This means that companies have to have more clinical trial sites to enroll enough patients.
- Small populations: The challenge of finding patients for clinical trials is inherent in orphan drug development even in an age when patients are more connected online than ever before.
- Lack of endpoints, outcome measures: Orphan diseases are often not as well studied or understood as more common diseases, and researchers often lack established endpoints to measure the impact of a treatment.
Despite these challenges, we have seen great progress in the fight against rare diseases in recent years, with 370 newly approved orphan indications in the last decade. This progress is thanks in part to the Orphan Drug Act, which has continued to foster innovative research. In addition, growing understanding of many rare diseases at the molecular and genetic levels has opened new doors to treatments.
Unfortunately, 95 percent of rare diseases still lack an approved treatment. We must continue to foster research into orphan diseases and tackle the many challenges inherent in rare disease research for the many patients still waiting for treatments.