Types of protection on the originator drug that have to be taken into account by generic drug manufacturers when filing applications for generic drugs in the US include the following:

• patents
• patent term extensions
• market exclusivity.

In Europe, data/regulatory exclusivity—at the time of regulatory submission— also has to be taken into account. Before this date, no submission to the EMA may be made.

Market exclusivity

Market exclusivity is the period during which a new drug is protected from direct competition from generics. It is therefore important for originator companies to try to maximise this period in order to recuperate their research and development costs.

Every day of market exclusivity is a potential profit for an originator company because generic drug companies capture 80% market share within six months of entering the US market [2].

In the US, the FDA grants marketing exclusivity for each newly approved drug or formulation as follows:

• new chemical entity (NCE) for 5 years
• new formulation for 3 years
• orphan drug for 7 years.

In the EU, the 8+2(+1) exclusivity period came into effect in late 2005. This period consists of:

• 8 years data exclusivity dating from the EMA authorisation decision: before that, no generic applications may be filed.
• +2 years marketing protection: no generic applications may be approved.
• + 1 year for new indication(s) if it constitutes a significant clinical benefit.

Patent Duration

Patents in the US and Europe last 20 years. Because the patent generally lasts longer than the exclusivity period granted for a NCE by the regulatory agencies the patent is often the barrier to generic entry rather than the exclusivity period.

However, since the drug development and regulatory process can often be lengthy, both the US and Europe provide exclusivity extensions for patented drugs in order to compensate somewhat for some of this delay.

The relationship between the date of patent filing and the initiation of clinical trials and the relationship between the date of patent filing and the market authorization date on the expected duration of marketing exclusivity are discussed in the following series of two articles.

Related articles

Effect of patent filing and initiation of clinical trials on market exclusivity

Concerns of patent filing and approval date on market exclusivity

Savings to be made and compliance with generic antidepressants

Still no word from FDA on generic user fees

Generic applications in the EU, patents and exclusivity

References

1. Dunn MK. Timing of patent filing and market exclusivity. Nature Reviews 2011;10:487-8.

2. GaBI Online - Generics and Biosimilars Initiative. Generics grab 80% share of US market and fill 78% of prescriptions. [www.gabionline.net]. Mol, Belgium: Pro Pharma Communications International; [cited 2011 July 5]. Available from: www.gabionline.net/Reports/Generics-grab-80-share-of-US-market-and-fill-78-of-prescriptions