NEW YORK (TheStreet) -- Shares of Arrowhead Pharmaceuticals (ARWR - Get Report) are jumping by 12.36% to $5.91 on heavy trading volume late Wednesday afternoon, following the release of encouraging data about the company's lead product candidate ARC-520, for the treatment of the hepatitis B virus (HBV) infection.

The Pasadena, CA-based biopharmaceutical company presented findings from its clinical and nonclinical studies at the International Liver Congress in Barcelona this week.

The results included that: "ARC-520 and entecavir produced rapid HBV DNA suppression with all hepatitis B e-antigen (HBeAg) positive, treatment naïve patients achieving serum HBV DNA reductions of up to 5.5 log (99.9997%), and all HBeAg negative, treatment naïve patients achieving reductions that put them below the limit of quantitation," the company said in a statement earlier today.

The treatment also effectively inhibited the infection with observed viral protein reduction in patients of up to 2.0 log (99%) after a single dose, Arrowhead said.

"These are exciting results that continue to show that ARC-520 can reduce the production of HBV viral proteins. We have ongoing multiple-dose and combination studies designed to assess if this will allow the body's natural immune defenses to control the virus and lead to a functional cure," CEO Chris Anzalone stated.

About 2.29 million of the company's shares were traded by late this afternoon, well above its average volume of 568,498 shares per day.

Separately, TheStreet Ratings Team has a "Sell" rating with a score of D on the stock.

The company's weaknesses can be seen in multiple areas, such as its disappointing return on equity and generally disappointing historical performance in the stock itself.

Recently, TheStreet Ratings objectively rated this stock according to its "risk-adjusted" total return prospect over a 12-month investment horizon. Not based on the news in any given day, the rating may differ from Jim Cramer's view or that of this articles's author.

You can view the full analysis from the report here: ARWR