# Methimazole.
**AGENCY:**
Food and Drug Administration, HHS.
**ACTION:**
Final rule.
**SUMMARY:**
The Food and Drug Administration (FDA) is amending the animal drug regulations to reflect the original approval of a new animal drug application (NADA) filed by Dechra, Ltd. The NADA provides for the veterinary prescription use of methimazole tablets in cats for treatment of hyperthyroidism.
**DATES:**
This rule is effective June 11, 2009.
**FOR FURTHER INFORMATION CONTACT:**
Melanie R. Berson, Center for Veterinary Medicine (HFV-110), Food and Drug Administration, 7500 Standish Pl., Rockville, MD 20855, 240-276-8337, e-mail: *[email protected]* .
**SUPPLEMENTARY INFORMATION:**
Dechra, Ltd., Dechra House, Jamage Industrial Estate, Talke Pits, Stoke-on-Trent, Staffordshire, ST7 1XW, United Kingdom, filed NADA 141-292 that provides for veterinary prescription use of FELIMAZOLE (methimazole) Coated Tablets in cats for the treatment of hyperthyroidism. The NADA is approved as of May 27, 2009, and the regulations are amended in 21 CFR part 520 to reflect the approval.
In accordance with the freedom of information provisions of 21 CFR part 20 and 21 CFR 514.11(e)(2)(ii), a summary of safety and effectiveness data and information submitted to support approval of this application may be seen in the Division of Dockets Management (HFA-305), Food and Drug Administration, 5630 Fishers Lane, rm. 1061, Rockville, MD 20852, between 9 a.m. and 4 p.m., Monday through Friday.
Under section 512(c)(2)(F)(i) of the Federal Food, Drug, and Cosmetic Act (21 U.S.C. 360b(c)(2)(F)(i)), this approval qualifies for 5 years of marketing exclusivity beginning on the date of approval.
FDA has determined under 21 CFR 25.33 that this action is of a type that does not individually or cumulatively have a significant effect on the human environment. Therefore, neither an environmental assessment nor an environmental impact statement is required.
This rule does not meet the definition of “rule” in 5 U.S.C. 804(3)(A) because it is a rule of “particular applicability.” Therefore, it is not subject to the congressional review requirements in 5 U.S.C. 801-808.
**List of Subjects in 21 CFR Part 520**
Animal drugs.
**21 CFR Part 520**
Therefore, under the Federal Food, Drug, and Cosmetic Act and under authority delegated to the Commissioner of Food and Drugs and redelegated to the Center for Veterinary Medicine, 21 CFR part 520 is amended as follows:
**21 CFR Part 520**
**PART 520—ORAL DOSAGE FORM NEW ANIMAL DRUGS**
1. The authority citation for 21 CFR part 520 continues to read as follows:
**Authority:**
21 U.S.C. 360b.
**21 CFR Part 520**
2. Add § 520.1372 to read as follows:
§ 520.1372
(a) *Specifications* . Each tablet contains 2.5 or 5 milligrams (mg) methimazole.
(b) *Sponsor* . See No. 043264 in § 510.600 of this chapter.
(c) *Conditions of use in cats* —(1) *Amount* . The starting dose is 2.5 mg every 12 hours. Following 3 weeks of treatment, the dose should be titrated to effect based on individual serum total T4 levels and clinical response.
(2) *Indications for use* . For the treatment of hyperthyroidism.
(3) *Limitations* . Federal law restricts this drug to use by or on the order of a licensed veterinarian.
Dated: June 5, 2009.
Bernadette Dunham,
Director, Center for Veterinary Medicine.