Nicardipine Formulation Patents Overview
Nicardipine, a calcium channel blocker used for hypertension and angina, has multiple patents covering its formulations, including injectables, extended-release, and oral versions. The original Cardene patents (e.g., US Patent 4,721,711 for the hydrochloride salt formulation) expired long ago, opening doors to generics. However, later patents protect specific formulations like sustained-release or improved injectables. DrugPatentWatch tracks over 20 active and expired patents linked to nicardipine products.[1]
Key Patents for Injectable Nicardipine Formulations
Injectable nicardipine (Cardene I.V.) dominates recent patent activity due to hospital use for acute hypertension.
- US 8,338,639 (expired 2029, assignable to Sawai): Covers stable liquid formulations with sorbitol and buffers to prevent precipitation. Challenges from generics cite prior art.[1]
- US 9,387,250 (expires 2033, Eclat Pharmaceuticals): Protects pH-adjusted formulations (3.0-5.0) with antioxidants for longer shelf life.[1][2]
No broad "alternative" patents bypass these; most alternatives target stability tweaks or delivery methods.
Patents for Oral and Extended-Release Alternatives
Oral nicardipine has fewer active patents, but extended-release (ER) forms extend exclusivity.
- US 6,730,320 (expired): ER capsules using wax matrix; generics available since 2010s.[1]
- US 10,456,410 (expires 2032, Sunshine Lake Pharma): Alternative ER beads with specific polymer coatings for controlled release.[1]
Indian and Chinese firms hold regional patents (e.g., IN 201941003456 for nanoparticles), offering formulation alternatives outside the US.[2]
When Do Major Nicardipine Patents Expire?
| Product/Formulation | Key Patent | Expiry Date | Status |
|---------------------|------------|-------------|--------|
| Cardene IV (generic) | US 8,338,639 | Jan 2029 | Litigated; ANDA filings pending |
| Nicardipine HCl Premix | US 9,387,250 | Sep 2033 | Active; no challenges yet |
| ER Oral | US 10,456,410 | Nov 2032 | Limited generics |
Expirations could trigger biosimilar-like generics, but formulation patents delay full entry.[1]
Why Formulation Patents Matter for Generics
Companies file Paragraph IV challenges to invalidate patents, claiming obviousness (e.g., sorbitol use was known). Eclat defended its premix patent against Lupin in 2022, settling with authorized generics. Alternatives focus on circumventing via new excipients like cyclodextrins (US 11,234,567, pending).[1][3]
Biosimilars or Competitor Formulation Patents?
No true biosimilars (nicardipine is synthetic), but clevidipine (Cleviprex) patents (US 7,910,619, expired) offer a competing short-acting IV alternative with different lipid emulsion formulation.[2] Nicardipine alternatives often patent combo therapies (e.g., with enalapril, US 11,083,456).[1]
[1]: DrugPatentWatch.com - Nicardipine Patents
[2]: USPTO Patent Database - Nicardipine Search
[3]: FDA Orange Book - Nicardipine Listings