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 Idera Pharmaceuticals, Inc. (NASDAQ:IDRA) began Thursday's trading with a pop of over 15%, but have been falling throughout the trading day and might possibly return to breakeven by the closing bell.

So what: The day's gains kicked in once Idera publicized an agreement with Abbott Labs (NYSE:ABT) to develop a companion diagnostic for genetically defined forms of B-cell lymphoma. The test, which Abbott will develop, will be administered in vitro to detect the presence of MYD88 L265P oncogenic mutations in tumor biopsy samples. This will help determine the feasibility of treating such mutations with Idera's development-stage toll-like receptor antagonist drug IMO-8400.

Now what: The unsustainability of today's pop might simply be due to the fact that Idera's shares had already grown 1,000%, and then lost roughly 60% of that pop, over the past year -- shareholders are still sitting on a four-plus-bagger for the past 12 months, which implies that most of the optimism over IMO-8400 might already be baked into Idera's share price.

Idera itself notes that the particular variants of B-cell lymphoma it hopes to treat with IMO-8400 are only diagnosed in a total of 3,200 Americans every year, which is a rather small number of potential patients. Of course, Idera's shares have been horrible performers on a longer timeline -- they've lost over 99% of their value since going public in the 1990s -- so at this point, investing here is probably more speculation than anything else.

Alex Planes has no position in any stocks mentioned, and neither does The Motley Fool. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.