Arrowhead Research Shares Soar on Hepatitis B Study Results

Arrowhead Research Corp. released data Thursday showing its experimental hepatitis B treatment significantly reduced the virus in humans and chimpanzees, sending shares of the company soaring in early trading.

Shares of Arrowhead surged 34% to $9.05 a share in premarket trading. Shares of Arrowhead have gained 35% in the past month.

Arrowhead has been racing against competitors such as Gilead Sciences Inc. to develop a new hepatitis B drug. Jefferies analysts have projected Arrowhead's lead candidate, ARC-520, could potentially reach $4.5 billion in peak annual sales, with market entry around 2020. But some analysts have said the drug hasn't yet proven it can be a functional cure for the disease.

Arrowhead released the data ahead of an analyst day in New York.

Arrowhead said in human studies of patients who tested positive for the E-antigen, HBeAg, a single dose of ARC-520 reduced the antigen by up to 98%. The E-antigen is a protein made by the virus, which indicates that there is a lot of virus in the blood and it can be easily spread to others.

Hepatitis B can lead to liver diseases such as cirrhosis and cancer.

The treatment also reduced the S-antigen by up to 99% in human patients. The S-antigen is a surface antigen found in the blood of someone infected with hepatitis B. Arrowhead said it is currently conducting phase-two human trials of the drug.

The chimpanzee studies, which gave up to 11 monthly doses to 9 chimps, reduced the S-antigen by amounts ranging from 81% to 99%.

Arrowhead said it hasn't seen any serious or severe side effects in humans or chimps.

Write to Chelsey Dulaney at [e-mail]

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(END) Dow Jones Newswires

September 24, 2015 09:55 ET (13:55 GMT)

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