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 Immunomedics (IMMU), a clinical-stage biopharmaceutical company developing monoclonal antibody-based therapies to treat cancer and other autoimmune diseases, advanced as much as 20% after reporting positive early stage clinical data on 90 Y-clivatuzumab tetraxetan in combination with Eli Lilly's (LLY 1.29%) Gemzar in treating metastatic pancreatic cancer.

So what: According to Immunomedics' press release before the opening bell, patients who were treated with multiple cycles of clivatuzumab tetraxetan labeled with yttrium-90, and also given a low dose of Gemzar, demonstrated a median overall survival time of five months despite having received at least two prior therapies in a phase 1b trial. Immunomedics also noted that, "Median OS for patients with partial response or stable disease as best response was longer than those with disease progression (131 days vs. 66 days, respectively)."

Now what: Now comes the challenging part of conducting a late-stage clinical study of 90 Y-clivatuzumab tetraxetan with Gemzar in a target population of 440 people across the globe. Immunomedics plans to initiate this trial as early as the end of this year, or perhaps the beginning of 2014, and is focusing on overall survival as its primary endpoint.

Some of you might be scratching your head as to why the stock would be up as much as 20% with a median-OS of just five months. The reason is that pancreatic survival rates are very low, and those patients who are on their third-line therapy often have a median-OS that's about half of what 90 Y-clivatuzumab tetraxetan produced, or less. So this is, indeed, very exciting and encouraging news for Immunomedics and pancreatic cancer sufferers. With a growing pipeline that's complemented with an antibody-drug conjugate program as well, I'd strong suggest keeping a close eye on Immunomedics moving forward.