8-K

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM 8-K

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(D) OF
THE SECURITIES EXCHANGE ACT OF 1934

Date of report (Date of earliest event reported):December 15, 2004

Abgenix, Inc.

(Exact Name of Registrant as Specified in Its Charter)

Delaware
(State or Other Jurisdiction of Incorporation)
000-24207	94-3248826
(Commission File Number)	(IRS Employer Identification No.)
6701 Kaiser Drive, Fremont California	94555
(Address of Principal Executive Offices)	(Zip Code)
510-284-6500
(Registrant’s Telephone Number, Including Area Code)
(Former Name or Former Address, if Changed Since Last Report)

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):

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

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

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

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

Item 3.02               Unregistered Sales of Equity Securities

On December 15, 2004, Abgenix, Inc. (the “Company”) entered into a definitive agreement to offer and sell $225 million aggregate principal amount of 1.75% Convertible Senior Notes due 2011 (the “Notes”) in a private placement to qualified institutional buyers pursuant to the exemptions from the registration requirements of the Securities Act of 1933, as amended (the “Act”), afforded by Section 4(2) of the Act and Rule 144A under the Act.   In addition, the Company has granted the initial purchasers of the Notes an option to purchase up to an additional $75 million aggregate principal amount of the Notes.  The Notes will be convertible into shares of the Company’s common stock at an initial conversion rate of 78.0153 shares per $1,000 principal amount of Notes (which is equivalent to a conversion price of approximately $12.82 per share).  The offering will generate aggregate proceeds of approximately $217.8 million (approximately $290.5 million if the initial purchasers exercise in full their option to purchase additional Notes). Aggregate estimated offering expenses in connection with the transaction, including initial purchasers’ discounts and commissions, will be approximately $7.2 million (approximately $9.5 million if the initial purchasers exercise in full their option to purchase additional Notes). The offering is expected to close on December 21, 2004.

Item 8.01Other Events

On December 15, 2004, Abgenix, Inc. issued a press release announcing that it had priced its previously announced private placement of its Convertible Senior Notes due 2011.  A copy of the press release is attached to this current report on Form 8-K as Exhibit 99.1.

Item 9.01Financial Statements and Exhibits

(c)             Exhibits.

Exhibit No.	Description
99.1	Press Release of Abgenix, Inc. dated December 15, 2004

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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.

	ABGENIX, INC.
Dated: December 16, 2004	By:	/s/ H. Ward Wolff
		H. Ward Wolff
		Chief Financial Officer and Senior Vice President, Finance

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EXHIBIT INDEX

EXHIBIT NO.	DESCRIPTION
99.1	Press Release of Abgenix, Inc. dated December 15, 2004

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EX-99.1

Exhibit 99.1

FOR IMMEDIATE RELEASE
Contact:	Ami Knoefler
	Senior Director
	Corporate Communications & Investor Relations
	510-284-6350 or 510-284-6605

ABGENIX ANNOUNCES PRICING OF PRIVATE OFFERING OF CONVERTIBLE SENIOR NOTES

FREMONT, Calif., December 15, 2004 — Abgenix, Inc. (Nasdaq: ABGX) today announced it has priced its previously announced private placement under Rule 144A in an aggregate principal amount of $225 million of its Convertible Senior Notes due 2011. In addition, the company has granted the initial purchasers of the notes an option to purchase up to an additional $75 million principal amount of notes.  The notes will be convertible into common stock of the company at a conversion rate of 78.0153 shares per $1,000 principal amount of notes (representing an initial conversion price of approximately $12.82 per share) and will accrue interest at an annual rate of 1.75 percent.  The notes will mature in December 2011 and will be redeemable at the company’s option beginning in December 2009. The transaction is expected to close on December 21, 2004.  The closing is subject to customary closing conditions.

Abgenix intends to use a portion of the net proceeds of the offering from time to time to retire a portion of its outstanding Convertible Subordinated Notes due March 15, 2007.  Abgenix expects to use the remaining proceeds of the offering for research and development, capital expenditures, working capital and other corporate purposes.

The securities to be offered have not been registered under the Securities Act of 1933, as amended (the “Securities Act”), or any state securities laws, and unless so registered, may not be offered or sold in the United States except pursuant to an exemption from, or in a transaction not subject to, the registration requirements of the Securities Act and applicable state securities laws. This announcement does not constitute an offer to sell or the solicitation of an offer to buy any security and shall not constitute an offer, solicitation or sale in any jurisdiction in which such offering would be unlawful.

Abgenix’s statements in this press release that are not historical facts and that relate to future plans or events are forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. These forward-looking statements include Abgenix’s intention to raise proceeds through the offering and sale of convertible senior notes, the intended use of proceeds and the anticipated terms of such notes. There can be no assurance that Abgenix will complete the offering on the anticipated terms or at all. Abgenix’s ability to complete the offering will depend, among other things, on market conditions. In addition, Abgenix’s ability to complete this offering and Abgenix’s business are subject to the risks described in Abgenix’s quarterly report on Form 10-Q for the quarter ended September 30, 2004 and annual report on Form 10-K for the year ended December 31, 2003, which have been filled with the Securities and Exchange Commission.  Abgenix is providing this information as of the date of this press release and does not undertake any obligation to update any forward-looking statements.

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