Zevra Therapeutics Extends MIPLYFFA Exclusivity to 2041 with FDA Orange Book Patent Listing
Key Insights
Zevra Therapeutics has submitted U.S. Patent No. 11,707,456 for MIPLYFFA (arimoclomol) to the FDA for Orange Book listing, extending patent protection to November 19, 2041.
The Orange Book listing strengthens market exclusivity by enabling an automatic stay on generic approvals if a generic filer challenges the patent.
MIPLYFFA is approved for Niemann-Pick disease type C (search) (NPC), an ultra-rare, progressive neurodegenerative disease with significant unmet medical need.
Zevra Therapeutics, Inc. (NasdaqGS: ZVRA) announced on June 8, 2026, that it has submitted U.S. Patent No. 11,707,456 covering MIPLYFFA (arimoclomol) to the U.S. Food and Drug Administration for listing in the Orange Book, the FDA's official register of approved drug products and their associated patents. The patent expires on November 19, 2041, significantly extending the exclusivity window for the company's lead commercial asset.
"We are pleased to further strengthen our intellectual property protection for MIPLYFFA with the listing of this patent in the FDA's Orange Book," said Neil F. McFarlane, Zevra's President and Chief Executive Officer. "MIPLYFFA represents an important therapeutic option for people living with Niemann-Pick disease type C (search) (NPC), an ultra-rare, progressive, and devastating neurodegenerative disease with significant unmet need."
Strategic Importance of Orange Book Listing
The Orange Book serves as the FDA's authoritative listing of approved drug products and the patents and regulatory exclusivities associated with them. Patents listed in the Orange Book carry significant procedural weight: when a generic filer challenges a listed patent through an Abbreviated New Drug Application (ANDA), the listing can trigger an automatic 30-month stay on generic approvals, providing branded drugmakers with a critical procedural tool to defend market exclusivity.
By extending patent protection to 2041, Zevra lengthens the period over which it can market MIPLYFFA without direct generic competition tied to that patent, supporting the long-term revenue outlook for the asset. Shares of Zevra gained over 9.5% on the day of the announcement.
Pending Patent Term Extension
In addition to the Orange Book listing, Zevra has previously applied for a patent term extension for U.S. Patent No. 11,045,460, which currently expires in 2029. The company is awaiting a determination from the U.S. Patent and Trademark Office on that application. The parallel pursuit of both the Orange Book listing and the patent term extension reflects what McFarlane described as the company's "continued focus on maintaining and enhancing the intellectual property portfolio supporting MIPLYFFA."
Niemann-Pick Disease Type C (search) and MIPLYFFA
Niemann-Pick disease type C (search) is an ultra-rare, progressive neurodegenerative disease characterized by the body's inability to properly transport cholesterol and other lipids within cells, leading to neurological deterioration. MIPLYFFA, the brand name for arimoclomol, is marketed in the United States as a treatment for NPC.
Zevra Therapeutics is a commercial-stage company focused on developing and commercializing therapies for rare diseases. The company has stated that the commercialization of MIPLYFFA provides a strong corporate foundation and validates its ability to advance therapies from development to market. Zevra's broader strategy includes broadening access through geographic expansion opportunities and progressing its pipeline toward key milestones.