Potential Abbreviated New Drug Applications for Chlorthalidone

FDA says Thalitone was not withdrawn from the market due to safety or efficacy and can potentially have ANDA approvals.

The FDA recently determined that the drug Thalitone (chlorthalidone) was not withdrawn from sale for safety or effiacy reasons, which will allow the approval of abbreviated new drug applications (ANDAs) for chlorthalidone if all requirements are met.

The Drug and Price Competition and Patent Term Restoration Act of 1984 authorized the approval of duplicate drugs under an ANDA procedure. Applicants must show the drug they are seeking approval for has the same active ingredient in the same strength and dosage form as a previously approved drug.

Thalitone was initially approved in 1988 for the treatment of hypertension, either alone or in combination with other antihypertensive drugs.

The drug can also be used as an adjunctive therapy in edema associated with multiple conditions, such as congestive heart failure and hepatic cirrhosis. Currently, the drug is listed as discontinued.

In September 2015, Clinipace Worldwide submitted a citizen petition for the FDA to determine if Thalitone was withdrawn due to safety or efficacy reasons. The FDA reviewed files, relevant literature, and data and have determined that it was not withdrawn for those reasons.

ANDAs that refer to Thalitone could be approved by the FDA assuming that they meet all requirements for approval and if the labeling for the product needs to be revised, they will advise the applicant to do so.