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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

 

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FORM 8-K

 

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CURRENT REPORT

Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934

 

Date of Report (Date of earliest event reported): April 14, 2005

 

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Arrowhead Research Corporation

(Exact name of registrant as specified in its charter)

 

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Delaware		0-21898		46-0408024
(State or other jurisdiction of incorporation)		(Commission File Number)		(I.R.S. Employer Identification No.)

 

1118 East Green Street, Pasadena, CA		91106
(Address of principal executive offices)		(Zip Code)

 

Registrant’s telephone number, including area code: (626) 792-5549

 

Not Applicable

(Former name or former address, if changed since last report)

 

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Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

 

¨	Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

 

¨	Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

 

¨	Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

 

¨	Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

 

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Item 7.01. Regulation FD Disclosure.

 

On April 14, 2005, Arrowhead Research Corporation mailed a letter to Warrantholders intended to provide guidance on select matters. The letter is attached as Exhibit 10.1 hereto.

 

Item 9.01. Financial Statements and Exhibits.

 

(c) Exhibits.

 

Exhibit No.		Description
10.1		Letter to Warrantholders, dated as of April 11, 2005 and mailed April 14, 2005.

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SIGNATURES

 

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

 

Date: April 14, 2005