Inspections, Compliance, Enforcement, and Criminal Investigations

Merck Animal Health 1/28/16


Department of Health and Human Services logoDepartment of Health and Human Services

Public Health Service
Food and Drug Administration
 Rockville MD 20855 


January 28, 2016

Via United Parcel Service
Attention: Mr. Richard R. DeLuca Jr.
Executive Vice President and President,
Intervet Inc. (d/b/a Merck Animal Health)
2 Giralda Farms
Madison, NJ 07940

Dear Mr. DeLuca,

This letter concerns your levothyroxine product for dogs, Leventa® Oral Solution (Levothyroxine 1.0 mg/mL oral solution). FDA's Center for Veterinary Medicine reviewed product labeling submitted with your drug listing under section 510 of the FD&C Act and information available on your website.

Your levothyroxine product is indicated for use as a thyroid replacement therapy for dogs in all conditions where inadequate production of thyroid hormones occurs (hypothyroidism), which makes it a drug under section 201(g)(1) of the Federal Food, Drug, and Cosmetic Act (the FD& Act)[21 U.S.C. § 321(g)(1)]. In addition, our levothyroxine product is a new animal drug, as defined by section 201(v) of the FD&C Act [21 U.S.C. § 321(v)], because it is not generally recognized among experts qualified by scientific training and experience to evaluate the safety and effectiveness of animal drugs, as safe and effective for use under the conditions prescribed, recommended, or suggested in the labeling.

Your levothyroxine product is not the subject of an approved new animal drug application, conditionally approved new animal drug application, or index listing under sections 512, 571, and 572 of the FD&C Act [21 U.S.C. §§ 360b, 360ccc, and 360ccc-1]. Therefore the product is unsafe within the meaning of section 512(a) of the FD&C Act [21 U.S.C. § 360b(a)], and adulterated under section 501(a)(5) of the FD&C Act [21 U.S.C. § 351(a)(5)]. Introduction of an adulterated drug into interstate commerce is prohibited under section 301(a) of the FD&C Act [21 U.S.C. § 331(a)].

This letter is not intended to be an all-inclusive review of your products. FDA may take enforcement action against these products at any time if they are found to be in violation of the FD&C Act and its implementing regulations.

Failure to promptly correct the violations specified above may result in enforcement action without further notice. Enforcement action may include seizure of violative products and/or injunction against the manufacturers and distributors of violative products.

You should notify this office, in writing, within fifteen (15) working days of the receipt of this letter of the steps you have taken to bring your firm into compliance with the law. Your response should include any documentation necessary to show that correction has been achieved. If corrective action cannot be completed within fifteen (15) working days, state the reason for the delay and the date by which the corrections will be completed. Include copies of any available documentation demonstrating that corrections have been made.

Please direct your response to the U.S. Food and Drug Administration, 10 Waterview Blvd., 3rd Floor, Parsippany, New Jersey 07054. If you have any questions about the content of this letter, please contact Charles J. Chacko, Compliance Officer, at (973) 331-4946 (phone) or (973) 331-4969.


Eric Nelson,
Director Compliance
Center for Veterinary Medicine


Page Last Updated: 10/28/2016
Note: If you need help accessing information in different file formats, see Instructions for Downloading Viewers and Players.
Language Assistance Available: Español | 繁體中文 | Tiếng Việt | 한국어 | Tagalog | Русский | العربية | Kreyòl Ayisyen | Français | Polski | Português | Italiano | Deutsch | 日本語 | فارسی | English