Patents and Drug Approvals - Brief view

How patents are playing key role in drug approvals?
In US, the drug approvals are linked to patents. The Orange book is electronic listing of Approved drugs in US and corresnponding patents covering any of one or all API, formulation and method of use.
All NDA applicants are required to submit patent information related to their product and patent information submitted by NDA applicant will be listed in orange book.
When generic company wants to market generic version of approved product, they have to file ANDA with patent certifications. The patent certifications, as i explained in previous post, are four different types which are Para I, II, III and IV. Paragraph III is the certification included with ANDA when generic company ready to wait till patent expiry and Paragraph IV is challenging patent listed in Orange book stating that the listed patents are invalid or not infringed by ANDA submitted upon manufacture, distribute and sale.
When the generic company files ANDA with para IV certification, innovator will file legal suit in district court and result in 30 month stay on drug approval. If generic company win the suit, the 180 day exclusivity offered to generic company, during this 180 days no further generic drug (ANDA) approval will not made.
The para IV filings plays key role for generic companies and Para IV filing are listed by FDA without disclosing identity of orginator. Link: http://www.fda.gov/CDER/ogd/ppiv.htm
and it is important to mention is "maintaining patent protifolio is become companies intellectual asset".
In india dispute is going on to link drug approvals with patent as like US system, if interested read this articles
1. http://www.livemint.com/2008/05/02224246/Drug-companies-oppose-bid-to-l.html (Accessed 9th Aug 2008)
2. http://www.pharmaceutical-business-review.com/article_news.asp?guid=22F598E9-6257-46E5-B107-D11DA389D018 (Accessed 9th Aug 2008)
Please write comments

For further reading:
1. generic drug product development by leon shargel and isadore Kanfer, published by Marcel dekker (2005)
2. http://www.fda.gov/cder/orange/default.htm
3. http://www.fda.gov/cder/regulatory/applications/ANDA.htm
4. http://www.fda.gov/cder/regulatory/applications/NDA.htm