# Determination That Klonopin (Clonazepam) Tablets, 0.125 Milligrams and 0.25 Milligrams, Were Not Withdrawn From Sale for Reasons of Safety or Effectiveness
**AGENCY:**
Food and Drug Administration, HHS.
**ACTION:**
Notice.
**SUMMARY:**
The Food and Drug Administration (FDA or Agency) has determined that KLONOPIN (clonazepam) tablets, 0.125 milligrams (mg) and 0.25 mg, were not withdrawn from sale for reasons of safety or effectiveness. This determination will allow FDA to approve abbreviated new drug applications (ANDAs) for clonazepam tablets, 0.125 mg and 0.25 mg, if all other legal and regulatory requirements are met.
**FOR FURTHER INFORMATION CONTACT:**
Lars Flores, Center for Drug Evaluation and Research, Food and Drug Administration, 10903 New Hampshire Ave., Bldg. 51, Rm. 6281, Silver Spring, MD 20993-0002, 301-796-0724, *[email protected].*
**SUPPLEMENTARY INFORMATION:**
Section 505(j) of the Federal Food, Drug, and Cosmetic Act (FD&C Act) (21 U.S.C. 355(j)) allows the submission of an ANDA to market a generic version of a previously approved drug product. To obtain approval, the ANDA applicant must show, among other things, that the generic drug product: (1) has the same active ingredient(s), dosage form, route of administration, strength, conditions of use, and (with certain exceptions) labeling as the listed drug, which is a version of the drug that was previously approved, and (2) is bioequivalent to the listed drug. ANDA applicants do not have to repeat the extensive clinical testing otherwise necessary to gain approval of a new drug application (NDA).
Section 505(j)(7) of the FD&C Act requires FDA to publish a list of all approved drugs. FDA publishes this list as part of the “Approved Drug Products With Therapeutic Equivalence Evaluations,” which is known generally as the “Orange Book.” Under FDA regulations, drugs are removed from the list if the Agency withdraws or suspends approval of the drug's NDA or ANDA for reasons of safety or effectiveness or if FDA determines that the listed drug was withdrawn from sale for reasons of safety or effectiveness (21 CFR 314.162).
A person may petition the Agency to determine, or the Agency may determine on its own initiative, whether a listed drug was withdrawn from sale for reasons of safety or effectiveness. This determination may be made at any time after the drug has been withdrawn from sale, but must be made prior to approving an ANDA that refers to the listed drug (§ 314.161 (21 CFR 314.161)). FDA may not approve an ANDA that does not refer to a listed drug.
KLONOPIN (clonazepam) tablets, 0.125 mg and 0.25 mg, are the subject of NDA 017533, held by Cheplapharm Arzneimittel GmbH, and initially approved on April 9, 1997. KLONOPIN is indicated for seizure disorders and panic disorder.
KLONOPIN (clonazepam) tablets, 0.125 mg and 0.25 mg, are currently listed in the “Discontinued Drug Product List” section of the Orange Book.
Hyman, Phelps & McNamara, P.C. submitted a citizen petition dated June 20, 2025 (Docket No. FDA-2025-P-1808), under 21 CFR 10.30, requesting that the Agency determine whether KLONOPIN (clonazepam) tablets, 0.25 mg, were withdrawn from sale for reasons of safety or effectiveness. Although the citizen petition did not address the 0.125 mg strength, that strength has also been discontinued. On our own initiative, we have also determined whether that strength was withdrawn for safety or effectiveness reasons.
After considering the citizen petition and reviewing Agency records and based on the information we have at this time, FDA has determined under § 314.161 that KLONOPIN (clonazepam) tablets, 0.125 mg and 0.25 mg, were not withdrawn for reasons of safety or effectiveness. The petitioner has identified no data or other information suggesting that KLONOPIN (clonazepam) tablets, 0.125 mg and 0.25 mg, were withdrawn for reasons of safety or effectiveness. We have carefully reviewed our files for records concerning the withdrawal of KLONOPIN (clonazepam) tablets, 0.125 mg and 0.25 mg, from sale. We have also independently evaluated relevant literature and data for possible postmarketing adverse events. We have found no information that would indicate that these drug products were withdrawn from sale for reasons of safety or effectiveness.
Accordingly, the Agency will continue to list KLONOPIN (clonazepam) tablets, 0.125 mg and 0.25 mg, in the “Discontinued Drug Product List” section of the Orange Book. The “Discontinued Drug Product List” delineates, among other items, drug products that have been discontinued from marketing for reasons other than safety or effectiveness. ANDAs that refer to KLONOPIN (clonazepam) tablets, 0.125 mg and 0.25 mg, may be approved by the Agency as long as they meet all other legal and regulatory requirements for the approval of ANDAs. If FDA determines that labeling for these drug products should be revised to meet current standards, the Agency will advise ANDA applicants to submit such labeling.
Grace R. Graham,
Deputy Commissioner for Policy, Legislation, and International Affairs.