
[Federal Register Volume 88, Number 227 (Tuesday, November 28, 2023)]
[Notices]
[Pages 83136-83138]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-26106]


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DEPARTMENT OF HEALTH AND HUMAN SERVICES

Food and Drug Administration

[Docket No. FDA-2022-E-2101]


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

AGENCY: Food and Drug Administration, HHS.

ACTION: Notice.

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SUMMARY: The Food and Drug Administration (FDA or the Agency) has 
determined the regulatory review period for Korsuva 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 
Director of the U.S. Patent and Trademark Office (USPTO), Department of 
Commerce, for the extension of a patent which claims that human drug 
product.

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DATES: Anyone with knowledge that any of the dates as published (see 
SUPPLEMENTARY INFORMATION) are incorrect may submit either electronic 
or written comments and ask for a redetermination by January 29, 2024. 
Furthermore, any interested person may petition FDA for a determination 
regarding whether the applicant for extension acted with due diligence 
during the regulatory review period by May 28, 2024. See ``Petitions'' 
in the SUPPLEMENTARY INFORMATION section for more information.

ADDRESSES: You may submit comments as follows. Please note that late, 
untimely filed comments will not be considered. The https://www.regulations.gov electronic filing system will accept comments until 
11:59 p.m. Eastern Time at the end of January 29, 2024. Comments 
received by mail/hand delivery/courier (for written/paper submissions) 
will be considered timely if they are received on or before that date.

Electronic Submissions

    Submit electronic comments in the following way:
     Federal eRulemaking Portal: https://www.regulations.gov. 
Follow the instructions for submitting comments. Comments submitted 
electronically, including attachments, to https://www.regulations.gov 
will be posted to the docket unchanged. Because your comment will be 
made public, you are solely responsible for ensuring that your comment 
does not include any confidential information that you or a third party 
may not wish to be posted, such as medical information, your or anyone 
else's Social Security number, or confidential business information, 
such as a manufacturing process. Please note that if you include your 
name, contact information, or other information that identifies you in 
the body of your comments, that information will be posted on https://www.regulations.gov.
     If you want to submit a comment with confidential 
information that you do not wish to be made available to the public, 
submit the comment as a written/paper submission and in the manner 
detailed (see ``Written/Paper Submissions'' and ``Instructions'').

Written/Paper Submissions

    Submit written/paper submissions as follows:
     Mail/Hand Delivery/Courier (for written/paper 
submissions): Dockets Management Staff (HFA-305), Food and Drug 
Administration, 5630 Fishers Lane, Rm. 1061, Rockville, MD 20852.
     For written/paper comments submitted to the Dockets 
Management Staff, FDA will post your comment, as well as any 
attachments, except for information submitted, marked and identified, 
as confidential, if submitted as detailed in ``Instructions.''
    Instructions: All submissions received must include the Docket No. 
FDA-2022-E-2101 for ``Determination of Regulatory Review Period for 
Purposes of Patent Extension; KORSUVA.'' Received comments, those filed 
in a timely manner (see ADDRESSES), will be placed in the docket and, 
except for those submitted as ``Confidential Submissions,'' publicly 
viewable at https://www.regulations.gov or at the Dockets Management 
Staff between 9 a.m. and 4 p.m., Monday through Friday, 240-402-7500.
     Confidential Submissions--To submit a comment with 
confidential information that you do not wish to be made publicly 
available, submit your comments only as a written/paper submission. You 
should submit two copies total. One copy will include the information 
you claim to be confidential with a heading or cover note that states 
``THIS DOCUMENT CONTAINS CONFIDENTIAL INFORMATION.'' The Agency will 
review this copy, including the claimed confidential information, in 
its consideration of comments. The second copy, which will have the 
claimed confidential information redacted/blacked out, will be 
available for public viewing and posted on https://www.regulations.gov. 
Submit both copies to the Dockets Management Staff. If you do not wish 
your name and contact information to be made publicly available, you 
can provide this information on the cover sheet and not in the body of 
your comments and you must identify this information as 
``confidential.'' Any information marked as ``confidential'' will not 
be disclosed except in accordance with Sec.  10.20 (21 CFR 10.20) and 
other applicable disclosure law. For more information about FDA's 
posting of comments to public dockets, see 80 FR 56469, September 18, 
2015, or access the information at: https://www.govinfo.gov/content/pkg/FR-2015-09-18/pdf/2015-23389.pdf.
    Docket: For access to the docket to read background documents or 
the electronic and written/paper comments received, go to https://www.regulations.gov and insert the docket number, found in brackets in 
the heading of this document, into the ``Search'' box and follow the 
prompts and/or go to the Dockets Management Staff, 5630 Fishers Lane, 
Rm. 1061, Rockville, MD 20852, 240-402-7500.

FOR FURTHER INFORMATION CONTACT: Beverly Friedman, Office of Regulatory 
Policy, Food and Drug Administration, 10903 New Hampshire Ave., Bldg. 
51, Rm. 6250, Silver Spring, MD 20993, 301-796-3600.

SUPPLEMENTARY INFORMATION:

I. Background

    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 or biologic 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 Director of USPTO 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 has approved for marketing the human drug product, Korsuva 
(difelikefalin acetate). Korsuva is indicated for the treatment of 
moderate-to-severe pruritus associated with chronic kidney disease in 
adults undergoing hemodialysis. Subsequent to this approval, the USPTO 
received a patent term restoration application for Korsuva (U.S. Patent 
No. 7,402,564) from Cara Therapeutics, Inc., and the USPTO requested 
FDA's assistance in determining the patent's eligibility for patent 
term restoration. In a letter dated September 28, 2022, FDA advised the 
USPTO that this human drug product had undergone a regulatory review 
period and that the approval of Korsuva represented the first permitted

[[Page 83138]]

commercial marketing or use of the product. Thereafter, the USPTO 
requested that FDA determine the product's regulatory review period.

II. Determination of Regulatory Review Period

    FDA has determined that the applicable regulatory review period for 
Korsuva is 4,625 days. Of this time, 4,381 days occurred during the 
testing phase of the regulatory review period, while 244 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 (FD&C Act) (21 U.S.C. 355(i)) became effective: 
December 26, 2008. The applicant claims January 16, 2009, as the date 
the investigational new drug application (IND) became effective. 
However, FDA records indicate that the IND effective date was December 
26, 2008, 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 of the FD&C Act: December 23, 
2020. FDA has verified the applicant's claim that the new drug 
application (NDA) for Korsuva (NDA 214916) was initially submitted on 
December 23, 2020.
    3. The date the application was approved: August 23, 2021. FDA has 
verified the applicant's claim that NDA 214916 was approved on August 
23, 2021.
    This determination of the regulatory review period establishes the 
maximum potential length of a patent extension. However, the USPTO 
applies several statutory limitations in its calculations of the actual 
period for patent extension. In its application for patent extension, 
this applicant seeks 1,827 days of patent term extension.

III. Petitions

    Anyone with knowledge that any of the dates as published are 
incorrect may submit either electronic or written comments and, under 
21 CFR 60.24, ask for a redetermination (see DATES). Furthermore, as 
specified in Sec.  60.30 (21 CFR 60.30), any interested person may 
petition FDA for a determination regarding whether the applicant for 
extension acted with due diligence during the regulatory review period. 
To meet its burden, the petition must comply with all the requirements 
of Sec.  60.30, including but not limited to: must be timely (see 
DATES), must be filed in accordance with Sec.  10.20, must contain 
sufficient facts to merit an FDA investigation, and must certify that a 
true and complete copy of the petition has been served upon the patent 
applicant. (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.
    Submit petitions electronically to https://www.regulations.gov at 
Docket No. FDA-2013-S-0610. Submit written petitions (two copies are 
required) to the Dockets Management Staff (HFA-305), Food and Drug 
Administration, 5630 Fishers Lane, Rm. 1061, Rockville, MD 20852.

    Dated: November 21, 2023.
Lauren K. Roth,
Associate Commissioner for Policy.
[FR Doc. 2023-26106 Filed 11-27-23; 8:45 am]
BILLING CODE 4164-01-P


