Shares of Celsion Corporation (CLSN) are taking a beating Thursday morning after the company said that its phase III HEAT trial of ThermoDox for hepatocellular carcinoma, or liver cancer, failed to meet its primary endpoint of increasing survival rates in patients without the cancer progressing.

The HEAT Study, which included ThermoDox used in combination with radiofrequency ablation, was designed to show a 33 percent improvement in PFS with 80 percent power and a p-value = 0.05.  The trials, being conducted under a Special Protocol Assessment agreement with the FDA, was an international, multi-center, randomized, placebo-controlled study that randomized 701 liver cancer patients with intermediate, unresectable tumors to evaluate ThermoDox® combined with radiofrequency ablation versus radiofrequency ablation alone.

In the trial, ThermoDox® was well-tolerated with no unexpected serious adverse events, according to today’s statement.

“We are disappointed that the HEAT Study did not provide sufficient evidence of clinical effectiveness of ThermoDox as measured by the trial’s primary endpoint,” said Michael H. Tardugno, Celsion’s President and Chief Executive Officer.  Tardugno added that the company is considering following patients in the study for the secondary endpoint of overall survival rates and further analyzing the data to strategize on future developments of ThermoDox.

Hepatocellular carcinoma represents a major opportunity for substantial revenues to a company that can bring a new product to market.  There are very few treatment options for patients, with most dying from the disease within five years after diagnosis.  It’s the third leading cancer killer of men globally and fourth leading cause of death amongst all cancer patients.  750,000 new cases are diagnosed each year across the planet.  The World Health Organization places the disease fifth on its list of the largest cancers in the world and estimates that it may surpass lung cancer, the largest cancer by number of patients, by 2020 at its current pace.

Investors have been betting that Celsion was going to provide positive results from the pivotal trial.  Shares have been steadily climbing since last March from the $1.60 area to as high as $9.44 on January 15.  Just over a week ago, Zhejiang Hisun Pharmaceutical of China put $5 million upfront in a ThermoDox development deal for Asia with Celsion.

Those investor look to be unloading shares hand-over-fist in Thursday morning trading with the bad news.  Shares have plunged more than 80 percent to around $1.50 an hour into trading.