The FDA issued a new report on "Critical Path Opportunities for Generic Drugs" that officials say will smooth the process for more expeditious approval of future generic drugs. The report, which identifies "many of the unanswered scientific questions that impede the development of generic versions of commonly used drugs," is expected to be particularly useful in creating a pathway for the approval of asthma inhalers, nasal sprays, and topical skin applications such as antifungal creams?products for which bioequivalence is difficult to determine through straightforward tests of blood plasma levels.
In announcing the new Critical Path report, FDA officials cited the problems facing generic drug products that contain the ozone-depleting substance chlorofluorocarbon? products that must be withdrawn from the market after 2008. "The new report will help ensure the FDA has an adequate scientific basis to review inhaler applications that use an alternative, hydroflu-oroalkane," agency officials said.
The agency?s report also calls for research on new bioequiv-alence methods tailor-made for each challenging drug class. "These include lung function tests and molecular level imaging for inhalation drugs; particle size distribution tests for nasal sprays; and methods for direct measurement of drug delivered to the skin," the FDA officials explained.