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Generic drugs provide Americans with lower-cost
alternatives to the escalating costs of brand name drugs. An abbreviated new
drug application (ANDA) contains data that when submitted to the FDA's Office
of Generic Drugs (OGD) facilitates the review and ultimate approval of a safe
and effective innovator-equivalent drug. The Drug Price Competition and Patent
Term Restoration Act of 1984 established using bioequivalence as the basis for
approving generic copies of innovator drugs. This act expedites the
availability of less costly generics by permitting the FDA to approve ANDAs
without conducting costly and duplicative clinical trials. Once approved, OGD
assures the generic drug will perform the same as its respective innovator
drug. However, generics may differ in such characteristics as shape, scoring
configuration, release mechanisms, packaging, excipients, expiration
date/time, and minor aspects of labeling and storage conditions. With the
exception of language protected by patents or exclusivity, the labeling of the
generic, including directions for use, must be virtually the same as that of
the brand name product. Both brand name and generic drug manufacturing
facilities have to adopt the same standards of good manufacturing practices
and meet the FDA's specifications.
All approved drugs, both innovator and generic,
are listed in the FDA's Approved Drug Products with Therapeutic Equivalence
Evaluations (Orange Book). The only difference between a full approval and a
tentative approval is that the final approval of an application is delayed due
to an existing patent or exclusivity on the innovator drug. The tentative
approval becomes a full approval through a subsequent action letter to the
application holder.
In recent years, the OGD has approved increasing
numbers of ANDAs and is continuing to decrease the time to approval for these
applications. The use of generics has resulted in substantial savings to
consumers and the U.S. government (through Medicare, Medicaid, and other
government health care programs). According to the Congressional Budget
Office, consumers save up to $10 billion a year compared with the price of
innovator drugs. The FDA has approved about 7,000 generic drugs for various
treatments. Today, almost half of all prescriptions are filled with generic
drugs.
Following approval, both generic and brand name
companies must submit data to the FDA showing that their products continue to
meet the agency's specifications until the established expiration date. The
FDA regularly assesses the quality of generics on the market and thoroughly
evaluates reports about their performance. An FDA review found that the
average difference between the bioequivalence of more than 270 approved
generic drugs and their innovator counterparts was 3.5%. This estimate is
about the same as the difference found between batches of brand name products.
The total number of approved generics has
increased from 305 in 2001 to 537 in 2006--a 76% increase over six years with
an annual average of 406 approvals. The number of ANDAs approved for
first-time generics ranged from 61 to 158--a 159% increase over six years with
an average of 93 ANDAs approved per year. Tentative approvals ranged from 67
to 166, a 147% rise. The average number of ANDAs approved tentatively per year
was 104. ANDAs approved for "not first-time" generics ranked the highest in
number of approvals. They averaged at 209 over six years and ranged from 159
to 271 approvals per year. Thus, the "me-too" versions of already marketed
generics are on the rise, perhaps because the number of innovator drugs coming
off patent is decreasing.
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