Exhibit 10.4.1

ABGENIX, INC.

1998 DIRECTOR OPTION PLAN  (As Amended and Restated Effective April 26, 2001)

1.Purposes of the Plan.The purposes of this 1998 Director Option Plan are to attract and retain the
best available personnel for service as Outside Directors (as defined herein) of the Company, to provide additional incentive to the Outside Directors of the Company to serve as Directors, and to
encourage their continued service on the Board.

All
options granted hereunder shall be nonstatutory stock options.

2.Definitions.As used herein, the following definitions shall apply:



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3.Stock Subject to the Plan.Subject to the provisions of Section 10 of the Plan, the maximum
aggregate number of shares which may be optioned and sold under under the Plan is 250,000 Shares of Common Stock (the "Pool"). The Shares may be authorized, but unissued, or reacquired Common Stock.

If
an Option expires or becomes unexercisable without having been exercised in full, the unpurchased Shares which were subject thereto shall become available for future grant or sale
under the Plan (unless the Plan has terminated). Shares that have actually been issued under the Plan shall not be returned to the Plan and shall not become available for future distribution under the
Plan.

4.Administration and Grants of Options under the Plan.



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5.Eligibility.Options may be granted only to Outside Directors. All Options shall be automatically
granted in accordance with the terms set forth in Section 4 hereof.

The
Plan shall not confer upon any Optionee any right with respect to continuation of service as a Director or nomination to serve as a Director, nor shall it interfere in any way
with any rights which the Director or the Company may have to terminate the Director's relationship with the Company at any time.

6.Term of Plan.The Plan shall become effective upon the earlier to occur of its adoption by the
Board or its approval by the stockholders of the Company as described in Section 16 of the Plan. It shall continue in effect for a term of ten (10) years ending in 2008 unless sooner
terminated under Section 11 of the Plan.

7.Form of Consideration.The consideration to be paid for the Shares to be issued upon exercise of an
Option, including the method of payment, shall consist of (i) cash, (ii) check, (iii) other shares

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which (x) in the case of Shares acquired upon exercise of an Option, have been owned by the Optionee for more than six (6) months on the date of surrender, and (y) have a Fair
Market Value on the date of surrender equal to the aggregate exercise price of the Shares as to which said Option shall be exercised, (iv) delivery of a properly executed notice together with
such other documentation as the Company and the broker, if applicable, shall require to effect an exercise of the Option and delivery to the Company of the sale or loan proceeds required to pay the
exercise price, or (v) any combination of the foregoing methods of payment.

8.Exercise of Option.



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9.Non-Tranferability of Options.The Option may not be sold, pledged, assigned,
hypothecated, transferred, or disposed of in any manner other than by will or by the laws of descent or distribution and may be exercised, during the lifetime of the Optionee, only by the Optionee.

10.Adjustments Upon Changes in Capitalization, Dissolution, Merger or Asset Sale.



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11.Amendment and Termination of the Plan.



12.Time of Granting Options.The date of grant of an Option shall, for all purposes, be the date
determined in accordance with Section 4 hereof.

13.Conditions Upon Issuance of Shares.Shares shall not be issued pursuant to the exercise of an
Option unless the exercise of such Option and the issuance and delivery of such Shares pursuant thereto shall comply with all relevant provisions of law, including, without limitation, the Securities
Act of 1933, as
amended, the Exchange Act, the rules and regulations promulgated thereunder, state securities laws, and the requirements of any stock exchange upon which the Shares may then be listed, and shall be
further subject to the approval of counsel for the Company with respect to such compliance.

As
a condition to the exercise of an Option, the Company may require the person exercising such Option to represent and warrant at the time of any such exercise that the Shares are
being purchased only for investment and without any present intention to sell or distribute such Shares, if, in the opinion of counsel for the Company, such representation is required by any of the
aforementioned relevant provisions of law.

Inability
of the Company to obtain authority from any regulatory body having jurisdiction, which authority is deemed by the Company's counsel to be necessary to the lawful issuance
and sale of any Shares hereunder, shall relieve the Company of any liability in respect of the failure to issue or sell such Shares as to which such requisite authority shall not have been obtained.

14.Reservation of Shares.The Company, during the term of this Plan, will at all times reserve and
keep available such number of Shares as shall be sufficient to satisfy the requirements of the Plan.

15.Option Agreement.Options shall be evidenced by written option agreements in such form as the Board
shall approve.

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