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 of Inovio Pharmaceuticals Inc (NASDAQ:INO), a synthetic vaccine manufacturer with a focus on infectious diseases and cancer, spiked higher by as much as 19% after reporting positive preclinical results from its malaria DNA vaccine. Shares have since given up most of their gains and are up by just 3%.

So what: According to this morning's press release from Inovio, its SynCon DNA vaccine, which contains four malaria antigens and was delivered using its proprietary electroporation device known as Cellectra, demonstrated "strong and durable antibody and T-cell immune responses in small animals and non-human primates." Of particular interest is that researchers also found vaccine-induced CD8+ T-cells in the liver, which are particularly effective at wiping out a targeted disease. Inovio plans to initiate an early-stage trial of its vaccine sometime in 2014 utilizing approximately 30 patients.

Now what: Shares in Inovio have been nothing short of volatile lately as a slew of encouraging data and a poor earnings report have whipsawed shares violently. Today's new certainly can't be misconstrued as anything but good for Inovio shareholders; however, they would be wise to keep in mind that this was merely a preclinical study, and the vaccine could act completely differently once it begins being tested on human patients. As I've noted in recent weeks, Inovio has yet to deliver for shareholders over its three decades of research, and until such time as it does, I would suggest keeping to the sidelines.

Fool contributor Sean Williams has no material interest in any companies mentioned in this article. You can follow him on CAPS under the screen name TMFUltraLong, track every pick he makes under the screen name TrackUltraLong, and check him out on Twitter, where he goes by the handle @TMFUltraLong.

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