Law Offices of Howard G. Smith announces that a class action lawsuit has been filed in the United States District Court for the Central District of California on behalf of purchasers of the common stock of Arrowhead Research Corporation ("Arrowhead" or the "Company") (NASDAQ:ARWR) between August 12, 2014 and October 8, 2014, inclusive (the "Class Period").

Arrowhead is a biopharmaceutical company engaged in the development of RNA Interference ("RNAi") therapeutics to suppress disease-causing genes. The Company's RNAi therapeutic ARC-520 targets the hepatitis B virus, and currently is being tested for its effectiveness in using RNAi to halt the production of hepatitis B genes. The Complaint alleges that defendants misrepresented the true viral reduction level that ARC-520 can induce in humans, and failed to disclose that data from the Phase IIa study of ARC-520 did not support their assertions concerning the drug's ability to reduce certain levels of hepatitis B surface antigens in humans.

On October 8, 2014, the Company disclosed the results of its Phase IIa study of ARC-520, which revealed that ARC-520 dosed at 2 mg/kg only induced a reduction in hepatitis B surface antigens that was far short of the levels defendants previously suggested. Following this news, the Company's stock dropped $5.48 per share, or almost 44% below its previous closing price, to close at $7.03 per share on October 8, 2014, on extraordinary volume.

If you are a member of the Class described above, you have until December 9, 2014, to move the Court to serve as lead plaintiff, if you meet certain legal requirements. To be a member of the Class you need not take any action at this time; you may retain counsel of your choice or take no action and remain an absent member of the Class. If you wish to learn more about this action, please contact Howard G. Smith, Esquire, of Law Offices of Howard G. Smith, 3070 Bristol Pike, Suite 112, Bensalem, Pennsylvania 19020 by telephone at (215) 638-4847, Toll Free at (888) 638-4847, or by email to, or visit our website at

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