Opportunity
Federal Register #FDA2025E1672
FDA Regulatory Review Period Determinations for HYMPAVZI, ENCELTO, and ENFLONSIA (Patent Extension)
Buyer
Food and Drug Administration
Posted
April 03, 2026
Respond By
October 03, 2026
Identifier
FDA2025E1672
This notice from the Food and Drug Administration (FDA), part of the Department of Health and Human Services, announces the determination of regulatory review periods for three human biological products in support of patent term extension applications: - Government Buyer: - Food and Drug Administration (FDA), Office of the Commissioner - Department of Health and Human Services - OEMs and Vendors Mentioned: - Pfizer Inc. (HYMPAVZI) - Neurotech USA, Inc. (ENCELTO) - ENFLONSIA (OEM not specified) - Products/Services Requested: - No procurement of products or services is requested; this is an informational notice regarding regulatory review periods for patent extension purposes - Products under review: - HYMPAVZI (marstacimab-hncq), for hemophilia A and B patients aged 12 and older - Patent: U.S. Patent No. 10,550,200 - ENCELTO (revakinagene taroretcel-lwey), for idiopathic macular telangiectasia type 2 (Mac Tel) - Patent: U.S. Patent No. 10,195,140 - ENFLONSIA (details limited) - Unique or Notable Requirements: - The notice details the regulatory review periods (testing and approval phases) for each product - Public comments and petitions are invited regarding the accuracy of the review periods and due diligence - No acquisition, delivery, or service provision is involved; the notice is strictly for patent extension and regulatory timeline transparency
Description
The Food and Drug Administration (FDA) has determined the regulatory review period for the human biological product ENCELTO, which is used for the treatment of adults with idiopathic macular telangiectasia type 2. This determination is published as part of the process for a patent term extension application submitted to the U.S. Patent and Trademark Office (USPTO) by Neurotech USA, Inc. The regulatory review period includes a testing phase and an approval phase, with specific dates verified by the FDA. Interested parties may submit comments or petitions regarding the determination by specified deadlines.