Document:

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                         LA JOLLA PHARMACEUTICAL COMPANY
                                  EXHIBIT 10.44
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                                  ATTACHMENT A

        As a supplement to the letter agreement dated December 28, 2001 between
La Jolla Pharmaceutical Company ("LJP") and Bruce K. Bennett, Jr. ("BENNETT")
related to Bennett's employment by LJP, Bennett and LJP hereby agree as follows:

        In connection with Bennett's employment with LJP, LJP's management will
recommend to LJP's Board of Directors that LJP grant to Bennett an option to
purchase up to 40,000 shares of common stock of LJP. Such option, if granted,
shall be the "OPTION" for purposes hereof.

        If Bennett's employment is terminated by LJP without cause (as defined
below), or if a Change in Control of LJP (as defined below) occurs and Bennett's
employment with LJP or its successor "terminates in connection with" (as defined
below) that Change in Control and in the absence of any event or circumstance
constituting Cause, then:

                (i)     Bennett will be entitled to receive from LJP a severance
                        payment equal to his then-current base salary for a
                        period of six full calendar months from the date of
                        termination and an additional three full calendar months
                        if and when after the first six months he has not found
                        suitable employment, payable consistent with LJP's
                        normal payroll practices, provided that such payment
                        will be contingent upon execution and delivery by
                        Bennett and LJP of a mutual release, in form
                        satisfactory to LJP, of all claims arising in connection
                        with Bennett's employment with LJP and termination
                        thereof, and

                (ii)    Bennett will be entitled to receive for a period of six
                        full calendar months from the date of termination and an
                        additional three full calendar months if and when after
                        the first six months he has not found suitable
                        employment, medical and dental benefits coverage for
                        Bennett and/or his dependents through the Company's
                        available plans at the time and LJP will be responsible
                        to continue payment of all applicable deductions for
                        premium costs. After the Company's obligation to pay the
                        premiums for health and dental coverage Bennett and/or
                        his dependents will be eligible to continue plan
                        participation under COBRA.

                (iii)   Notwithstanding anything to the contrary in the option
                        plan (the "PLAN") pursuant to which all of Bennett's
                        existing options were granted, the Options shall
                        automatically vest and become fully exercisable as of
                        the date of termination of Executive's employment (the
                        "TERMINATION DATE"), notwithstanding any vesting or
                        performance conditions applicable thereto, and shall
                        remain exercisable for a period of one year following
                        the Termination Date or such longer period as is
                        provided by the Plan or grant pursuant to which the
                        Options were granted. However, notwithstanding the
                        foregoing, in no case will the Options be exercisable
                        beyond the duration of the original term thereof, and if
                        the Options qualify as an incentive stock option under
                        the Internal Revenue Code and applicable regulations
                        thereunder, the exercise period thereof shall not be
                        extended in such a manner as to cause the Options to
                        cease to qualify as an incentive stock option unless
                        Executive elects to forego incentive stock option
                        treatment and extend the exercise period thereof as
                        provided herein.

        For purposes hereof, "CHANGE IN CONTROL" of LJP has the meaning set
        forth in the Plan in its form as the date of grant of the Options.

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        For purposes hereof, "CAUSE" means Bennett has (i) engaged in serious
        criminal activity or other wrongful conduct that has an adverse impact
        on LJP, (ii) disregarded instructions given to him under the authority
        of LJP's Board of Directors, (iii) performed services for any person or
        entity other than LJP and appropriate civic organizations, or (iv)
        otherwise materially breached his employment or fiduciary
        responsibilities to LJP.

        For purposes hereof, Bennett's employment with LJP or its successor will
        be deemed to "TERMINATE IN CONNECTION WITH" a Change in Control if,
        within 180 days after the consummation of the Change of Control, (i)
        Bennett is removed from Bennett's employment by, or resigns his
        employment upon the request of, a person exercising practical voting
        control over LJP or its successor following the Change in Control or a
        person acting upon authority or at the instruction of such person; or
        (ii) Bennett's position is eliminated as a result of a reduction in
        force made to reduce over-capacity or unnecessary duplication of
        personnel and Bennett is not offered a replacement position with LJP or
        its successor as a Vice President with compensation and functional
        duties substantially similar to the compensation and duties in effect
        immediately before the Change in Control; or (iii) Bennett resigns his
        employment with the Company or its successor rather than comply with a
        relocation of his primary work site more than 50 miles from LJP's
        headquarters.

                In Witness Whereof, LJP and Bennett have entered into this
        agreement as of January 11, 2002.

La Jolla Pharmaceutical Company

  By: /s/ Steven B. Engle                    /s/ Bruce K. Bennett, Jr.
     ----------------------------------      ----------------------------------
          Steven B. Engle                        Bruce K. Bennett, Jr.
          Chairman & CEO                         Vice President of Manufacturing

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                                                                   Exhibit 4.6.2

                             SUPPLEMENTAL INDENTURE

               SUPPLEMENTAL INDENTURE (this "SUPPLEMENTAL INDENTURE"), dated as
of March 13, 2002, among Telephone Entertainment Network, Inc., a Delaware
corporation ("TELNT"), and Backwire.com, Inc., a Delaware corporation
("BACKWIRE," and collectively with TELNT, the "ADDITIONAL GUARANTORS"), Leap
Wireless International, Inc., a Delaware corporation (the "COMPANY"), Cricket
Communications Holdings, Inc., a Delaware corporation (the "GUARANTOR"), and
State Street Bank and Trust Company, a state chartered trust company organized
under the laws of the Commonwealth of Massachusetts, as trustee under the
indenture referred to below (the "TRUSTEE").

                               W I T N E S S E T H

               WHEREAS, the Company and the Guarantor have heretofore executed
and delivered to the Trustee an indenture (the "INDENTURE"), dated as of
February 23, 2000, providing for the issuance of an aggregate principal amount
at maturity of $225,000,000 of 12 1/2% Series A and Series B Senior Notes due
2010 and $668,000,000 14 1/2 Series A and Series B Senior Discount Notes due
2010;

               WHEREAS, Section 4.23 of the Indenture provides that under
certain circumstances the Company and the Guarantor are required to cause the
Additional Guarantors to execute and deliver to the Trustee a supplemental
indenture pursuant to which the Additional Guarantors shall unconditionally
guarantee all of the Company's Obligations under the Indenture and the
Securities pursuant to a guarantee (the "ADDITIONAL GUARANTEE") on the terms and
conditions of the Guarantee by the Guarantor in Article 10 of the Indenture and
on the other terms and conditions set forth herein;

               WHEREAS, pursuant to Section 4.23 of the Indenture, the Company,
Guarantor and Cricket Merger Sub, Inc., a Delaware corporation ("SUB"), have
heretofore executed and delivered to the Trustee a Supplemental Indenture dated
as of June 13, 2000, adding Sub as an Additional Guarantor under the Indenture;

               WHEREAS, Sub was merged with and into Guarantor effective as of
June 15, 2000, with Guarantor as the surviving corporation; and

               WHEREAS, pursuant to Section 7.01 of the Indenture, the Trustee
is authorized to execute and deliver this Supplemental Indenture.

               NOW, THEREFORE, in consideration of the foregoing and for other
good and valuable consideration, the receipt of which is hereby acknowledged,
the parties hereto mutually covenant and agree for the equal and ratable benefit
of the holders of the Securities as follows:

               1. CAPITALIZED TERMS. Capitalized terms used herein without
definition shall have the meanings assigned to them in the Indenture.

               2. AGREEMENT TO GUARANTEE. The Additional Guarantors hereby
agree, jointly and severally with all other guarantors, to guarantee the
Company's Obligations under the Indenture and the Securities on the terms and
subject to the conditions set forth herein

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and in Article 10 of the Indenture (including the obligation to pay Liquidated
Damages under the provisions of the Registration Rights Agreement) and to be
bound by all other applicable provisions of the Indenture. Pursuant to Section
10.01 of the Indenture, the Additional Guarantors agree that the Guarantees set
forth in Article 10 of the Indenture, as supplemented by their agreement to
guarantee contained herein shall remain in full force and effect and apply to
all of the Securities notwithstanding any failure by the Additional Guarantors
to endorse on such Securities a notation of the Additional Guarantee.

               3. RELEASE OF ADDITIONAL GUARANTOR. In the event that the holders
of any of the Company's other Indebtedness which is guaranteed by the Additional
Guarantors release the Additional Guarantors their guarantee in respect of such
other Indebtedness, except a discharge or release by or as a result of any
payment under the guarantee of such other Indebtedness by the Additional
Guarantors, the Additional Guarantors shall be automatically and unconditionally
released and discharged from their obligations under this Additional Guarantee;
provided, however, if, after such release, any guarantee under such other
Indebtedness is subsequently reincurred or reinstated, then such Additional
Guarantors reincurring or reinstating such guarantee under such other
Indebtedness shall execute and reinstate their Additional Guarantee hereunder.

               Upon receipt of an Officer's Certificate, the Trustee shall
execute any documents reasonably requested by the Company, the Guarantor or the
Additional Guarantors in order to evidence the release of such Additional
Guarantors from their obligations under the Additional Guarantee.

               4. NO RECOURSE AGAINST OTHERS. No direct or indirect stockholder,
employee, officer or director, as such, past, present or future of the Company,
the Guarantors or the Additional Guarantors or any successor entity shall have
any personal liability for any Obligations of the Company, the Guarantors or the
Additional Guarantors or any successor entity under the Additional Guarantee, by
reason of his or its status as such stockholder, employee, officer or director.

               Each Holder by accepting a Security waives and releases all such
liability, and such waiver and release is part of the consideration for the
issuance of the Securities.

               5. GOVERNING LAW. THE INTERNAL LAW OF THE STATE OF NEW YORK SHALL
GOVERN AND BE USED TO CONSTRUE THIS SUPPLEMENTAL INDENTURE.

               6. COUNTERPARTS. This Supplemental Indenture may be executed in
any number of counterparts and by the parties hereto in separate counterparts,
each of which when so executed shall be deemed to be an original and all of
which taken together shall constitute one and the same agreement.

               7. EFFECT OF THE HEADINGS. The Section headings herein are for
convenience only and shall not affect the construction hereof.

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               IN WITNESS WHEREOF, the parties hereto have caused this
Supplemental Indenture to be duly executed and attested, all as of the date
first above written.

<TABLE>
<S>                                         <C>
ADDITIONAL GUARANTORS:                      COMPANY:

TELEPHONE ENTERTAINMENT                     LEAP WIRELESS INTERNATIONAL,
NETWORK, INC.                               INC.

By:     /s/ S. DOUG HUTCHESON               By:    /s/ HARVEY P. WHITE
    --------------------------------            ----------------------------------------
        Name:  S. Doug Hutcheson                   Name:  Harvey P. White
        Title: Senior Vice President               Title: Chairman of the Board and CEO

BACKWIRE.COM, INC.                          GUARANTOR:

                                            CRICKET COMMUNICATIONS
                                            HOLDINGS, INC on behalf of
                                            itself and as successor in
                                            interest to Cricket Merger
                                            Sub, Inc.

By:     /s/ S. DOUG HUTCHESON
    ------------------------------
        Name:  S. Doug Hutcheson
        Title: Senior Vice President        By:    /s/ HARVEY P. WHITE
                                                ------------------------------------------
                                                   Name:  Harvey P. White
                                                          Title: Chairman of the Board and CEO

                                            TRUSTEE:

                                            STATE STREET BANK AND TRUST
                                            COMPANY

                                            By:    /s/ MICHAEL M. HOPKINS
                                               --------------------------------------------
                                                   Name:  Michael M. Hopkins
                                                   Title: Vice President
</TABLE>

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