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 Geron (NASDAQ:GERN) are trading 26% higher this morning after the FDA removed a full clinical hold on the company's application for imetelstat.

So what: The FDA reversed an earlier decision to place imetelstat on clinical hold and declared the company's clinical development plan acceptable this morning, after acknowledging that Geron has no plans to develop imetelstat as a treatment for essential thrombocythemia or polycythemia vera.

Geron had been required to produce additional information from its studies of imetelstat-treated patients who experienced liver function test abnormalities that showed a return to baseline, and Geron's Phase 2 trials produced the adequate data. The FDA's demand for information on the reversibility of liver toxicity following long-term imetelstat treatment in animals was also met by nonclinical toxicology study data.

Now that the hold has lifted, Geron plans to begin a multicenter Phase 2 clinical trial in the first half of 2015.

Now what: Geron's investigational new drug application for imetelstat -- a telomerase inhibitor for treating cancer -- had been on clinical hold since March, which resulted in a whopping two-thirds decline in its share price, since imetelstat is Geron's only pipeline product at present. After today's pop, investors have a loss of only 40% for the year to date, which indicates that investors are more skittish now following a multimonth period of limbo. Fool healthcare specialists Sean Williams and Todd Campbell have suggested keeping a safe distance from Geron until clearer clinical data emerges, and this seems like the smart approach to a tiny biotech company with only one speculative early stage drug in clinical trials.