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Unapproved Drugs: Opportunities for Rapid Approval and Market Exclusivity


Contrary to popular belief, there are many unapproved drugs which are actively being used. Many physicians may not even realize that that the drugs they are prescribing have not been through thorough tests for safety and efficacy. The reason why these drugs are on the market relates to the history of FDA regulations (more on that below), and the FDA is actively trying to encourage the development of approvable versions of these unapproved drugs.

See our comprehensive list of unapproved drugs

A Brief History of FDA Regulations

Currently, the FDA requires that any new drug must be proven to be both safe and effective prior to receiving marketing authorization, but this was not always the case. In 1938 the Federal Food Drug and Cosmetics Act, requiring that drugs be proven safe before coming to the market.  The Kefauver-Harris Amendments were added in 1962, necessitating that drugs also be proven efficacious before they could be approved. But the amendments created a dilemma – how should the FDA regulate the drug products that had been approved between 1938 and 1962? The decision was made that these drugs would remain on the market, but that they would need to classified as ‘effective’, ‘ineffective’, or ‘needing further study’. The name of the program established to conduct these reviews was called DESI – Drug Efficacy Study Implementation. Importantly, drugs which are found ‘effective’ under DESI still require formal FDA approval to obtain marketing clearance.

The FDA Moves to Accelerate Approval of DESI Drugs

In 2006 the FDA released a final guidance entitled “Marketed Unapproved Drugs—Compliance Policy Guide,” which outlined a new drug safety initiative aimed at removing unapproved drugs from the market. Importantly, one of the categories of drugs targeted for enforcement was drugs that lack evidence of effectiveness. That is, DESI drugs for which efficacy had never been formally established.

The impact of this new initiative is that if a company obtains formal approval for a drug that other companies are marketing without approval, the FDA intends to initiate enforcement action against the unapproved products, providing an incentive for companies seeking approval while simultaneously removing unapproved drugs from the market.

Other Incentives for Seeking Approval of Unapproved Drugs

Unapproved drugs often have a wealth of information from their widespread use, which may make them eligible for a 505(b)(2) approval pathway — a hybrid between the traditional NDA or ANDA processes that enables the submission of clinical data not developed by the NDA applicant. This can result in a much less expensive and much faster route to approval. Additionally, 3 years exclusivity may be available for applications that require a clinical study or 5 years exclusivity for a new chemical entity.

See our comprehensive list of unapproved drugs

Also published on Medium.

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