Orphan drugs generally follow the same regulatory development path as any other pharmaceutical product, in which testing focuses on
pharmacokinetics and
pharmacodynamics,
dosing, stability, safety and efficacy. However, some statistical burdens are lessened to maintain development momentum. For example, orphan drug regulations generally acknowledge the fact that it may not be possible to test 1,000 patients in a
phase III clinical trial if fewer than that number are affected by the disease. Government intervention on behalf of orphan drug development takes several forms: •
Tax incentives • Exclusivity (enhanced patent protection and marketing rights) • Research subsidies • Creating a government-run enterprise to engage in research and development as in a
Crown corporation A 2015 study of "34 key Canadian stakeholders, including drug regulators, funders, scientists, policy experts, pharmaceutical industry representatives, and patient advocates" investigated factors behind the pharmaceutical industry growing interest in "niche markets" such as orphan drugs.
United States The
Orphan Drug Act (ODA) of January 1983, passed in the
United States, with lobbying from the
National Organization for Rare Disorders and many other organizations, is meant to encourage
pharmaceutical companies to develop drugs for diseases that have a small market. Under the ODA drugs, vaccines, and diagnostic agents would qualify for orphan status if they were intended to treat a disease affecting fewer than 200,000 American citizens. Under the ODA orphan drug sponsors qualify for seven-year FDA-administered market Orphan Drug Exclusivity (ODE), "tax credits of up to 50% of R&D costs, R&D grants, waived FDA fees, protocol assistance Orphan drug status granted by the European Commission gives marketing exclusivity in the EU for 10 years after approval. The EU's legislation is administered by the
Committee on Orphan Medicinal Products of the
European Medicines Agency (EMA). In late 2007 the FDA and EMA agreed to use a common application process for both agencies to make it easier for manufacturers to apply for orphan drug status but, while continuing two separate approval processes.
Other countries Legislation has been implemented by Japan, Singapore, and Australia that offers subsidies and other incentives to encourage the development of drugs that treat orphan diseases.
Numbers of new drugs Under the ODA and EU legislation, many orphan drugs have been developed, including drugs to treat
glioma,
multiple myeloma,
cystic fibrosis,
phenylketonuria,
snake venom poisoning, and
idiopathic thrombocytopenic purpura. The Pharmaceutical Executive opines, that the "ODA is nearly universally acknowledged to be a success". Before the
US Congress enacted the ODA in 1983, only 38 drugs were approved in the US specifically to treat orphan diseases. In the US, from January 1983 to June 2004, 249 orphan drugs received marketing authorization and 1,129 received different orphan drug designations, compared to fewer than ten such products in the decade prior to 1983. From 1983 until May 2010, the FDA approved 353 orphan drugs and granted orphan designations to 2,116 compounds. As of 2010, 200 of the roughly 7,000 officially designated orphan diseases have become treatable. Though not technically an orphan disease, research and development into the treatment for
AIDS has been heavily linked to the
Orphan Drug Act. In the beginning of the AIDS epidemic the lack of treatment for the disease was often accredited to a believed lack of commercial base for a medication linked to
HIV infection. This encouraged the FDA to use the Orphan Drug Act to help bolster research in this field, and by 1995 13 of the 19 drugs approved by the FDA to treat AIDS had received orphan drug designation, with 10 receiving marketing rights. These are in addition to the 70 designated orphan drugs designed to treat other HIV related illnesses. ==Examples for selected diseases==