Exhibit 10.58

AGREEMENT AND GENERAL RELEASE

MedImmune, Inc. and Gregory S. Patrick, his heirs, executors, administrators, successors, and assigns (collectively referred to throughout this Agreement
as "Employee"), agree that:

1.Last Day of Employment.Employee's last day of employment with Employer is
January 16, 2004.

2.Consideration.In consideration for signing this Agreement and General Release and
compliance with the promises made herein, Employer agrees:



3.No Consideration Absent Execution of this Agreement.Employee understands and agrees
that he would not receive the monies and/or benefits specified in paragraph "2" above, except for his execution of this Agreement and General Release and the fulfillment of the promises contained
herein.

4.General Release of Claims.Employee knowingly and voluntarily releases and forever
discharges Employer, its parent corporation, affiliates, subsidiaries, divisions, successors and assigns and the current and former employees, officers, directors and agents thereof (collectively
referred to throughout the remainder of this Agreement as "Employer"), of and from any and all claims, known and unknown,

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Employee
has or may have against Employer as of the date of execution of this Agreement and General Release, including, but not limited to, any alleged violation of:



5.Affirmations.

Employee
affirms that he has not filed, caused to be filed, or presently is a party to any claim, complaint, or action against Employer in any forum or form.

Employee
further affirms that he has been paid and/or has received all leave (paid or unpaid), compensation, wages, bonuses, commissions, and/or benefits to which he may be entitled and
that no other leave (paid or unpaid), compensation, wages, bonuses, commissions and/or benefits are due to him, except (1) any already vested benefit under ERISA, and (2) as provided in
this Agreement and General Release.

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Employee
furthermore affirms that he has no known workplace injuries or occupational diseases and has been provided and/or has not been denied any leave requested under the Family and
Medical Leave Act.

Employee
acknowledges that because of circumstances unique to him including, but not limited to, irreconcilable differences with Employer, he is not qualified to hold any position with
Employer now or in the future and, therefore, shall not apply in the future for employment with Employer.

Employee
affirms that he has returned any and all of Employer's property in his possession or control.

6.Confidentiality.Employee agrees not to disclose any information regarding the
existence or substance of thus Agreement and General Release, except to his spouse, tax advisor, and an attorney with whom Employee chooses to consult regarding his consideration of this Agreement and
General Release. Employee also affirms he has not divulged any proprietary or confidential information of Employer and will not divulge such information at anytime hereafter.

7.Indemnification.MedImmune, Inc. agrees to indemnify employee
against all liabilities and expenses, including reasonable attorneys' fees, actually or necessarily incurred by or imposed upon him in connection with any proceeding in which he may be made a party,
or in which he may become involved, by reason of his being or having been a director, officer or employee of the corporation, or any settlement thereof, whether or not he is a director, officer or
employee at the time such expenses and liabilities accrue, except in such cases wherein the director, officer or employee is adjudged guilty of will-ful misfeasance or malfeasance or
negligence in the performance of his duties."

8.Governing Law and Interpretation.This Agreement and General Release shall be
governed and conformed in accordance with the laws of the state in which Employee was employed at the time of his last day of employment without regard to its conflict of laws provision. In the event
the Employee breaches any provision of this Agreement and General Release, Employee and Employer affirm that either may institute an action to specifically enforce any term or terms of this Agreement
and General Release. Should any provision of this Agreement and General Release be declared illegal or unenforceable by any court of competent jurisdiction and cannot be modified to be enforceable,
excluding the general release language, such provision shall immediately become null and void, leaving the remainder of this Agreement and General Release in full force and effect.

9.Nonadmission of Wrongdoing.The parties agree that neither this Agreement and General
Release nor the furnishing of the consideration for this Release shall be deemed or construed at anytime for any purpose as an admission by either party of any liability or unlawful conduct of any
kind.

10.Amendment.This Agreement and General Release may not be modified, altered or
changed except upon express written consent of both parties wherein specific reference is made to this Agreement and General Release.

11.Revocation.Employee may revoke this Agreement and General Release for a period of
seven (7) calendar days following the day he executes this Agreement and General Release. Any revocation within this period must be submitted, in writing, to Pamela J. Lupien and state, "I
hereby revoke my acceptance of our Agreement and General Release." The revocation must be personally delivered to Pamela J. Lupien or her designee, or mailed to Pamela J. Lupien and postmarked within
seven (7) calendar days of execution of this Agreement and General Release. This Agreement and General Release shall not become effective or enforceable until the revocation period has expired.
If the last day of the revocation period is a Saturday, Sunday, or legal holiday in the state in which Employee was employed at the time of his last day of employment, then the revocation period shall
not expire until the next following day which is not a Saturday, Sunday, or legal holiday.

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12.Entire Agreement.This Agreement and General Release sets forth the entire agreement
between the parties hereto, and fully supersedes any prior agreements or understandings between the parties, except
the Employee Proprietary Information and Invention Agreement. Employee acknowledges that he has not relied on any representations, promises, or agreements of any kind made to him in connection with
his decision to accept this Agreement and General Release, except for those set forth in this Agreement and General Release.

EMPLOYEE HAS BEEN ADVISED THAT HE HAS UP TO TWENTY-ONE (21) CALENDAR DAYS TO REVIEW THIS AGREEMENT AND GENERAL RELEASE AND HAS BEEN ADVISED IN
WRITING TO CONSULT WITH AN ATTORNEY PRIOR TO EXECUTION OF THIS AGREEMENT AND GENERAL RELEASE.

EMPLOYEE AGREES THAT ANY MODIFICATIONS, MATERIAL OR OTHERWISE, MADE TO THIS AGREEMENT AND GENERAL RELEASE DO NOT RESTART OR AFFECT IN ANY MANNER THE ORIGINAL
TWENTY-ONE (21) CALENDAR DAY CONSIDERATION PERIOD.

HAVING ELECTED TO EXECUTE THIS AGREEMENT AND GENERAL RELEASE, TO FULFILL THE PROMISES AND TO RECEIVE THE SUMS AND BENEFITS IN PARAGRAPH "2" ABOVE, EMPLOYEE FREELY
AND KNOWINGLY, AND AFTER DUE CONSIDERATION, ENTERS INTO THIS AGREEMENT AND GENERAL RELEASE INTENDING TO WAIVE, SETTLE AND RELEASE ALL CLAIMS HE HAS OR MIGHT HAVE AGAINST
EMPLOYER.

IN
WITNESS WHEREOF, the parties hereto knowingly and voluntarily executed this Agreement and General Release as of the date set forth below:

|/s/ GREGORY S. PATRICKGregory S. Patrick |  |                                     
|---------------------------------------- |  | ------------------------------------
|Date:                                    |  | December 31, 2003                   
|MedImmune, Inc.                          |  |                                     
|By:                                      |  | /s/ PAMELA J. LUPIENPamela J. Lupien
|Date:                                    |  | December 31, 2003                   
|By:                                      |  | /s/ DAVID M. MOTTDavid M. Mott      
|Date:                                    |  | January 5, 2004                     

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