Approximately 90% of rare diseases still have no effective treatments, despite regulators implementing expedited approval pathways for these indications. Rare diseases are defined in the European Union (EU) as those that affect less than one in 2,000 people. There could be as many as 7,000 rare diseases, meaning the aggregate number of patients they actually impact is huge; it is estimated to be around 30 million across Europe, representing one in 17 people.
GlobalData’s Pharmaceutical Technology writer Allie Nawrat looks at the challenges facing drug development and reimbursement for rare diseases.
Clinical trial and data-related challenges
Nawrat says: “Regulators and reimbursing agencies still view large, randomised, placebo-controlled trials as the gold standard for measuring safety and efficacy.
“However, in rare diseases, because of the small patient populations, multiple disease sub-types and diagnosis challenges as clinicians may never have seen this disease before, it is difficult to identify and recruit enough patients with similar disease states into a randomised clinical trial.
“It is also common for regulators to want to see clinically appropriate endpoints that can be compared to placebo groups, but because there have been few previous clinical trials in certain diseases, there is a lack of established endpoints.
“Placebo groups for rare diseases, particularly those that primarily affect children, are largely viewed as unethical. There is a call for a patient’s natural history to be used as a comparator.”
Barriers to reimbursement
Nawrat says: “There has been a gradual improvement in the biological understanding of the largely genetic causes of these complex conditions. Cell and gene therapies can bring long-term, durable, and potentially curative benefit to patients, but they are incredibly expensive to manufacture and complicated to administer.
“This causes challenges for reimbursement agencies who need to weigh up safety and efficacy factors against value for money in terms of improvement in patients’ quality of life and the practicalities of rolling out these therapies into routine commissioning.”