The first so-called "biosimilar" products -- copy versions of patented biotech medicines -- are expected to be approved in Europe by the end of 2006, while such products are unlikely to arrive in the US market until 2009. There are currently eight biogeneric marketing applications filed with European Union (EU) regulator EMEA.

Industry players fear that generics could soon undermine the profits of biotech companies in the way that copy drugs have impacted traditional manufacturers. Recent statistics indicate that sales of biotech products reached US$56.2bn in 2004. Of this total, US$20.2bn was derived from products deemed at high risk of generic competition.

However, generic companies will be hampered by the fact that biotech products are far more complex than traditional chemical drugs, meaning there will be additional expense and difficulty at every stage of development. Research-based drugmakers claim that extensive clinical trials are necessary to ascertain the safety of biotech drugs, an expense that generic firms may be unable to meet.

In the EU, a compromise has been brokered with generic companies required to provide full pre-clinical data, but only a small amount of clinical trial research, the most expensive part of drug development. In the US, these disparities have yet to be resolved, with innovator drug firms urging tougher safety rules for biogenerics.