Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares in Ziopharm Oncology (TCRT -10.57%) sank by more than 10% today following dramatic gains notched after reporting an immunotherapy research deal with the MD Anderson Cancer Center in January.

So What: Shares in Ziopharm Oncology have surged 117% higher since the company announced on January 14th that it would be collaborating with the MD Anderson Cancer Center to develop medicine based on research into chimeric antigen receptor T cell, or CAR-T, therapies.

CAR-T therapies have gotten a lot of attention this year following the high profile IPOs of the clinical stage biotech companies Kite Pharma and Juno Therapeutics. Each of these companies is developing new medicines designed to help the immune system more easily identify and destroy cancer cells.

Ziopharm's agreement with MD Anderson brings together MD Anderson's CAR-T research, Intrexon Corp's research into using interleukin-12 modules to switch on and off T-cell activity, and Ziopharm's immuno-oncology research. Ziopharm thinks that this combination will allow it to deliver a best-in-class CAR-T offering that is easier to manufacture and more practical to roll out across a large patient population than the approaches being employed by its competitors.

Now What: Inking MD Anderson as a collaborator helps validate Ziopharm's approach, but it does so at a cost. Under the agreement, Ziopharm is paying MD Anderson $50 million in common stock, as well as committing to spend tens of millions in the coming years to finance research and development.

While CAR-T therapies are intriguing in their ability to more precisely deliver cancer killing agents to cancer cells, research into them remains in the early stages. As a result, there's a lot of risk for investors -- especially since it's likely to be years before there's a hint of a potential commercial product.

For that reason, its probably not shocking to see investors retreating today and locking in some profits. After all, emerging stocks like Ziopharm should probably only be owned by speculative investors that can take a hit from a failed research trial. Otherwise, it's probably best to see how research trials pan out before stepping in and buying this one.