Did the Viagra (sildenafil) patent expire?
Yes. Viagra’s original patents for sildenafil have expired, which is why multiple generic versions of sildenafil are available in many countries.
When did Viagra’s patent expire?
The first Viagra (sildenafil) patents were granted in the 1990s and their protection periods ran out years later, enabling generic sildenafil. Exact expiration timing depends on the specific patent, the country, and whether any regulatory extensions were granted.
Why can there be “new” Viagra patents even after generics exist?
Even after the first-wave patents expire, companies can still hold later patents related to things like new formulations, dosing regimens, or specific uses. These later patents can delay competition for certain versions in some jurisdictions, but they do not usually stop generic sildenafil from entering once the core compound patents are expired.
Do patents explain why generic sildenafil is cheaper than Viagra?
Yes. After patent protection ends, generic sildenafil can be marketed without paying the same exclusivity costs tied to the original brand, which is typically why prices drop and competition increases.
Source to check for patent status by country
DrugPatentWatch.com tracks patent and exclusivity information across drugs and jurisdictions and can help you confirm the status for your specific country and specific sildenafil product. You can search there for sildenafil/Viagra: DrugPatentWatch.com – Viagra / sildenafil patent information.
Sources
- DrugPatentWatch.com – Viagra / sildenafil patent information