Anytime a megablockbuster nears the end of its IP-protected life, plenty of companies will emerge to get a piece of the pie. In this case, Roche (NASDAQOTH:RHHBY) has two megablockbusters with a combined $13.5 billion in 2012 sales coming off patent in the next several years. That is bad news for the innovator, but opens a big opportunity for the various companies targeting biosimilars. In fact, a total of 19 trials are under way to develop generic versions of Rituxan and Herceptin. In the following video, Fool contributor Maxx Chatsko tells investors which companies to keep an eye on in the race to unseat Roche.

Fool contributor Maxx Chatsko has no position in any stocks mentioned. Check out his personal portfolio, his CAPS page, or follow him on Twitter @BlacknGoldFool to keep up with his writing on energy, bioprocessing, and emerging technologies.

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