[Federal Register Volume 62, Number 138 (Friday, July 18, 1997)]
[Notices]
[Pages 38562-38563]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-18910]


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DEPARTMENT OF HEALTH AND HUMAN SERVICES

Food and Drug Administration
[Docket No. 97E-0067]


Determination of Regulatory Review Period for Purposes of Patent 
Extension; ZYFLOTM

AGENCY: Food and Drug Administration, HHS.

ACTION: Notice.

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SUMMARY: The Food and Drug Administration (FDA) has determined the 
regulatory review period for ZYFLOTM and is publishing this 
notice of that determination as required by law. FDA has made the 
determination because of the submission of an application to the 
Commissioner of Patents and Trademarks, Department of Commerce, for the 
extension of a patent which claims that human drug product.

ADDRESSES: Written comments and petitions should be directed to the 
Dockets Management Branch (HFA-305), Food and Drug Administration, 
12420 Parklawn Dr., rm. 1-23, Rockville, MD 20857.

FOR FURTHER INFORMATION CONTACT: Brian J. Malkin, Office of Health 
Affairs (HFY-20), Food and Drug Administration, 5600 Fishers Lane, 
Rockville, MD 20857, 301-443-1382.

SUPPLEMENTARY INFORMATION: The Drug Price Competition and Patent Term 
Restoration Act of 1984 (Pub. L. 98-417) and the Generic Animal Drug 
and Patent Term Restoration Act (Pub. L. 100-670) generally provide 
that a patent may be extended for a period of up to 5 years so long as 
the patented item (human drug product, animal drug product, medical 
device, food additive, or color additive) was subject to regulatory 
review by FDA before the item was marketed. Under these acts, a 
product's regulatory review period forms the basis for determining the 
amount of extension an applicant may receive.
    A regulatory review period consists of two periods of time: A 
testing phase and an approval phase. For human drug products, the 
testing phase begins when the exemption to permit the clinical 
investigations of the drug becomes effective and runs until the 
approval phase begins. The approval phase starts with the initial 
submission of an application to market the human drug product and 
continues until FDA grants permission to market the drug product. 
Although only a portion of a regulatory review period may count toward 
the actual amount of extension that the Commissioner of Patents and 
Trademarks may award (for example, half the testing phase must be 
subtracted as well as any time that may have occurred before the patent 
was issued), FDA's determination of the length of a regulatory review 
period for a human drug product will include all of the testing phase 
and approval phase as specified in 35 U.S.C. 156(g)(1)(B).
    FDA recently approved for marketing the human drug product 
ZYFLOTM (zileuton). ZYFLOTM is indicated for the 
prophylaxis and chronic treatment of asthma in adults and children 12 
years of age and older. Subsequent to this approval, the Patent and 
Trademark Office received a patent term restoration application for 
ZYFLOTM (U.S. Patent No. 4,873,259) from Abbott 
Laboratories, and the Patent and Trademark Office requested FDA's 
assistance in determining this patent's eligibility for patent term 
restoration. In a letter dated March 12, 1997, FDA advised the Patent 
and Trademark Office that this human drug product had undergone a 
regulatory review period and that the approval of ZYFLOTM 
represented the first permitted commercial marketing or use of the 
product. Shortly thereafter, the Patent and Trademark Office requested 
that FDA determine the product's regulatory review period.
    FDA has determined that the applicable regulatory review period for 
ZYFLOTM is 3,329 days. Of this time, 2,454 days occurred 
during the testing phase of the regulatory review period, while 875 
days occurred during the approval phase. These periods of time were 
derived from the following dates:
    1. The date an exemption under section 505(i) of the Federal Food, 
Drug, and Cosmetic Act (21 U.S.C. 355(i)) became effective: October 31, 
1987. The applicant claims October 30, 1987, as the date the 
investigational new drug application (IND) became effective. However, 
FDA records indicate that the IND effective date was October 31, 1987, 
which was 30 days after FDA receipt of the IND.
    2. The date the application was initially submitted with respect to 
the human drug product under section 505(b) of the Federal Food, Drug, 
and Cosmetic Act: July 19, 1994. The applicant claims July 18, 1994, as 
the date the new drug application (NDA) for ZYFLOTM (NDA 20-
471) was initially submitted. However, FDA records indicate that NDA 
20-471 was submitted on July 19, 1994.
    3. The date the application was approved: December 9, 1996. FDA has 
verified the applicant's claim that NDA 20-471 was approved on December 
9, 1996.
    This determination of the regulatory review period establishes the 
maximum potential length of a patent extension. However, the U.S. 
Patent and Trademark Office applies several statutory limitations in 
its calculations of the actual period for patent extension. In its 
application for patent extension, this applicant seeks 1,398 days of 
patent term extension.
    Anyone with knowledge that any of the dates as published is 
incorrect may, on or before September 16, 1997 submit to the Dockets 
Management Branch (address above) written comments and ask for a 
redetermination. Furthermore, any interested person may petition FDA, 
on or before January 14, 1998 for a determination regarding whether the 
applicant for extension acted with due diligence during the regulatory 
review

[[Page 38563]]

period. To meet its burden, the petition must contain sufficient facts 
to merit an FDA investigation. (See H. Rept. 857, part 1, 98th Cong., 
2d sess., pp. 41-42, 1984.) Petitions should be in the format specified 
in 21 CFR 10.30.
    Comments and petitions should be submitted to the Dockets 
Management Branch (address above) in three copies (except that 
individuals may submit single copies) and identified with the docket 
number found in brackets in the heading of this document. Comments and 
petitions may be seen in the Dockets Management Branch between 9 a.m. 
and 4 p.m., Monday through Friday.

    Dated: July 8, 1997.
Allen B. Duncan,
Acting Associate Commissioner for Health Affairs.
[FR Doc. 97-18910 Filed 7-17-97; 8:45 am]
BILLING CODE 4160-01-F