Are there any FDA approved aptamer drugs?

The Approved Drug: Pegcetacoplan (Empaveli/Syfovre)

This is actually a single aptamer molecule with two distinct FDA approvals for different diseases:

1. Paroxysmal Nocturnal Hemoglobinuria (PNH): Approved in 2021 under the brand name Empaveli. It is a complement C3 inhibitor used to treat adults with PNH.

2. Geographic Atrophy (GA): Approved in 2023 under the brand name Syfovre. It is used to treat GA secondary to age-related macular degeneration (AMD).

How it works: Pegcetacoplan is a pegylated (attached to a polyethylene glycol chain for longer circulation) aptamer that binds specifically to complement protein C3. By inhibiting C3, it suppresses a central part of the body’s complement immune system, which is overactive in both PNH and GA.

Important Context and Other Notable Aptamers

• First-Ever Approval: The first aptamer therapeutic ever approved was Pegaptanib (Macugen) in 2004 for wet AMD. It targets VEGF. While it was a pioneering drug, it has since been largely superseded by more effective antibody-based treatments (like ranibizumab and aflibercept). It is still approved but rarely used.

• International Approvals: Another significant aptamer is Avacincaptad pegol (Izervay), which was also FDA-approved for Geographic Atrophy in 2023. It works by inhibiting complement C5.

• Aptamers in Diagnostics: While therapeutic aptamers are rare, aptamers are widely used in research and diagnostic tools. A famous example is the SOMAscan platform, which uses thousands of Slow Off-rate Modified Aptamers (SOMAmers) to detect proteins for research and clinical diagnostics.

Why Are There So Few FDA-Approved Aptamer Drugs?

Despite their promise (high specificity, low immunogenicity, chemical synthesis), aptamers face significant challenges:

• Rapid Degradation and Clearance: Naked RNA/DNA aptamers are quickly broken down in blood. They require chemical modification (like pegylation in Pegcetacoplan) to be stable.

• Delivery Challenges: Getting aptamers to target tissues inside the body (beyond the eye or bloodstream) is difficult.

• Intense Competition: The monoclonal antibody field is more mature and established, making it harder for aptamer drugs to compete in many disease areas.

In summary:
Yes, there is an FDA-approved aptamer drug class, with Pegcetacoplan (Empaveli/Syfovre) being the prime example for systemic and ocular use. The pathfinder was Pegaptanib (Macugen). The field is active, with aptamers like Avacincaptad pegol also gaining approval, but development has been slower than initially anticipated due to scientific and market challenges.