CHAPEL HILL, N.C. – A proposed aspirin combination that Pozen calls “Safer Aspirin” has performed well in early tests, the pharmaceutical firm said Tuesday.

The news tripped an 8.5 percent surge in Pozen (NASDAQ: POZN) shares. The stock traded at $15.45, up $1.21 or 8.5 percent, in late afternoon trading.

By the close, Pozen shares ended up $1.46, or 10.25 percent.

Pozen is scheduled to disclose its quarterly earnings today.

The product called Safer Aspirin PA 235 is a patented combination of aspirin coated with what Pozen calls a “proton pump inhibitor.” It was tested in a proof-of-concept study.

Two groups of 40 people over 50 years in age took PA 325 or a commercially available aspirin on the same 325mg dose and coated. Ten percent of PA 325 subjects showed gastrointestinal damage compared to 57.5 percent of the coated aspirin subjects, Pozen said. It also reported that no ulcers were seen in the PA 325 group while 20 percent of the other subjects developed gastric ulcers.

Pozen described the differences as “statistically significant.”

"The data from this first clinical study with PA 325 is very encouraging,” said John Plachetka, Pozen’s chairman and chief executive officer, in a statement.