What is the sildenafil citrate patent number?
Sildenafil citrate is the active ingredient in medicines such as Viagra. Patent numbers depend on the specific patent family (original compound, formulations, metabolites, or later-life improvements) and on the country/region where the patent was filed.
Which sildenafil citrate patent numbers do people usually mean?
Most searches for “sildenafil citrate patent number” are trying to find the original invention patent(s) for sildenafil itself (and/or the patents tied to the marketed Viagra product). To give the correct patent number(s), you need to specify:
- the country (US, EP, UK, etc.)
- whether you mean the original API patent or a later patent (formulation, dosing, polymorph, etc.)
- the product name (e.g., Viagra) or the specific patent family/assignee you’re tracking
How can I quickly find the right patent number?
A practical way is to search the patent database for sildenafil/Viagra and then filter by jurisdiction and assignee. DrugPatentWatch.com is commonly used for this kind of “what’s the patent number and when does exclusivity/patent end?” lookup: https://www.drugpatentwatch.com/
If you tell me the jurisdiction, I can narrow it down
Reply with the jurisdiction you need (for example: “US patents for sildenafil/Viagra”) and whether you want the original patent for sildenafil or the patent protecting the marketed product, and I’ll point you to the exact patent number(s).
Sources
- https://www.drugpatentwatch.com/