What: Shares of Immunomedics (NASDAQ:IMMU), a small-cap antibody-based therapeutics company developing treatments for cancer and autoimmune diseases, briefly rose by as much as 21% today on heavy volume. The stock's rapid rise was triggered by a positive clinical update for the company's lead antibody-drug conjugate (ADC), sacituzumab govitecan, in a midstage study for relapsed or refractory metastatic lung cancer. 

Per the press release, an interim analysis based on 57 patients, that included 28 non-small-cell lung cancer (NSCLC) and 29 small-cell lung cancer (SCLC) patients, suggested that the drug was exhibiting a noteworthy therapeutic signal in a heavily pre-treated group of patients.

Digging into the details, Immunomedics said that about a third of both NSCLC and SCLC patients receiving doses less than or equal to 12 mg/kg exhibited objective responses. The small groups of NSCLC and SCLC patients receiving the 10 mg/kg dose were also showing an interesting trend in terms of median progression-free (PFS) survival as well. The company plans on adding more patients to this dosage cohort going forward to further assess PFS and overall survival. 

So what: Immunomedics' shares took a beating earlier this year after its licensing partner UCB announced that epratuzumab failed to meet its primary endpoint in a late-stage study for lupus. This failure put the onus squarely on 90Y-Clivatuzumab tetraxetan, as a potential treatment for pancreatic cancer, to create value to shareholders in the near-term. With sacituzumab govitecan now showing some compelling midstage results in the metastatic lung cancer arena, Immunomedics' pipeline once again has a couple of interesting clinical candidates that could drive shares higher in the short to intermediate future.

Now what: Immunomedics is plotting a broad development program for sacituzumab govitecan across a host of indications such as NSCLC and SCLC, as well as triple-negative breast, esophageal, urothelial, and colorectal cancers, according to the company. Unfortunately, the drugmaker exited the second quarter of 2015 with only $99.6 million in cash, cash equivalents, and marketable securities, meaning that a major expansion in its clinical activities will probably require a sizable secondary offering. As such, you may want to stick to the sidelines with this speculative biotech until its long-term financing needs are secure. 


George Budwell has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. 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.