<PAGE>   1
EXHIBIT 10.44





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                               SECURITY AGREEMENT

                          Dated as of February 5, 1998

                                    between

                   FIRST SECURITY BANK, NATIONAL ASSOCIATION,
            not individually, but solely as the Owner Trustee under
                     the Guilford Real Estate Trust 1998-1

                                      and

                           FIRST UNION NATIONAL BANK,
                  as the Agent for the Lenders and the Holders



                         and accepted and agreed to by

                         GUILFORD PHARMACEUTICALS INC.



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<PAGE>   2
                               TABLE OF CONTENTS

<TABLE>
  <S>                                                                                                                        <C>
  1. DEFINITIONS.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
  2. GRANT OF SECURITY INTEREST. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
  3. PAYMENT OF OBLIGATIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
  4. OTHER COVENANTS.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
  5. DEFAULT; REMEDIES.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
  6. REMEDIES NOT EXCLUSIVE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
  7. PERFORMANCE BY THE AGENT OF THE BORROWER'S OBLIGATIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
  8. DUTY OF THE AGENT.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
  9. POWERS COUPLED WITH AN INTEREST.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
  10. EXECUTION OF FINANCING STATEMENTS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
  11. SECURITY AGREEMENT UNDER UNIFORM COMMERCIAL CODE.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
  12. AUTHORITY OF THE AGENT.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
  13. NOTICES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
  14. SEVERABILITY.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
  15. AMENDMENT IN WRITING; NO WAIVERS; CUMULATIVE REMEDIES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
  16. SECTION HEADINGS.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
  17. SUCCESSORS AND ASSIGNS.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
  18. THE BORROWER'S WAIVER OF RIGHTS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
  19. GOVERNING LAW. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
  20. OBLIGATIONS ARE WITHOUT RECOURSE.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
  21. PARTIAL RELEASE; FULL RELEASE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
  22. MISCELLANEOUS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
</TABLE>





                                      i

<PAGE>   3
<TABLE>
  <S>                                                                                                                        <C>
  23. CONFLICTS WITH PARTICIPATION AGREEMENT.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
  24. LESSEE AS A PARTY  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12

</TABLE>




                                      ii

<PAGE>   4
                               SECURITY AGREEMENT


         This SECURITY AGREEMENT, dated as of February 5, 1998 (as amended,
modified, extended, supplemented, restated and/or replaced from time to time,
this "Security Agreement"), is made between FIRST SECURITY BANK, NATIONAL
ASSOCIATION, a national banking association, not individually, but solely as
Owner Trustee under the Guilford Real Estate Trust 1998-1 (the "Borrower"), and
FIRST UNION NATIONAL BANK, a national banking association ("Bank"), as agent
for (a) the Lenders (hereinafter defined) under the Credit Agreement dated as
of February 5, 1998 (as amended, modified, extended, supplemented, restated
and/or replaced from time to time, the "Credit Agreement") by and among the
Borrower, the lending institutions from time to time parties thereto (the
"Lenders") and Bank as the agent for the Lenders and (b) the holders of the
certificates issued pursuant to the Amended and Restated Trust Agreement dated
as of February 5, 1998 (as amended, modified, extended, supplemented, restated
and/or replaced from time to time, the "Trust Agreement") among the holders
from time to time parties thereto (the "Holders") and the Borrower, in its
individual capacity thereunder and in its capacity as Owner Trustee thereunder.
The Lenders and the Holders, together with their successors and permitted
assigns, are collectively referred to hereinafter as the "Secured Parties."
Bank, in its capacity as agent for the Secured Parties is referred to
hereinafter as the "Agent," and this Security Agreement is accepted and agreed
to by GUILFORD PHARMACEUTICALS INC., a Delaware corporation.

                             Preliminary Statement

         Pursuant to the Credit Agreement, the Lenders have severally agreed to
make Loans to the Borrower in an aggregate amount not to exceed $19,400,000
upon the terms and subject to the conditions set forth therein, to be evidenced
by the Notes issued by the Borrower under the Credit Agreement.  Pursuant to
the Trust Agreement, the Holders have agreed to purchase the ownership
interests of the Trust created thereby in an aggregate amount not to exceed
$600,000 upon the terms and subject to the conditions set forth therein, to be
evidenced by the Certificates issued by the Borrower under the Trust Agreement.
The Borrower is, or shall be upon the date of the initial Advance with respect
to each Property, the legal and beneficial owner of such Property (except the
Borrower may have a ground leasehold interest in certain Properties pursuant to
one (1) or more Ground Leases).

         It is a condition, among others, to the obligation of the Lenders to
make their respective Loans to the Borrower under the Credit Agreement and the
Holders to make their respective Holder Advances under the Trust Agreement that
the Borrower shall have executed and delivered this Security Agreement to the
Agent, for the benefit of the Lenders and the Holders.

         NOW, THEREFORE, in consideration of the premises and to induce the
Lenders to make their respective Loans under the Credit Agreement and to induce
the Holders to make their respective Holder Advances under the Trust Agreement,
the Borrower hereby agrees with the Agent, for the benefit of the Lenders and
the Holders, as follows:





<PAGE>   5
         1.      DEFINITIONS.

         (a)     As used herein, the following terms shall have the following
respective meanings:

                 "Accounts" shall mean all "accounts," as such term is defined
         in the Uniform Commercial Code, now owned or hereafter acquired by the
         Borrower, including without limitation (i) all accounts receivable,
         other receivables, book debts and other forms of obligations now owned
         or hereafter received or acquired by or belonging or owing to the
         Borrower, whether arising out of goods sold or leased or services
         rendered by it or from any other transaction (including without
         limitation any such obligations which may be characterized as an
         account under the Uniform Commercial Code), (ii) all of the Borrower's
         rights in, to and under all purchase orders or receipts now owned or
         hereafter acquired by it for goods or services, (iii) all of the
         Borrower's rights to any goods represented by any of the foregoing
         (including without limitation unpaid sellers' rights of rescission,
         replevin, reclamation and stoppage in transit and rights to returned,
         reclaimed or repossessed goods), (iv) all monies due or to become due
         to the Borrower under all purchase orders and contracts for the sale
         or lease of goods or the performance of services or both by the
         Borrower (whether or not yet earned by performance on the part of the
         Borrower now) or hereafter in existence, including without limitation
         the right to receive the proceeds of said purchase orders and
         contracts, and (v) all collateral security and guarantees of any kind,
         now or hereafter in existence, given by any Person with respect to any
         of the foregoing.

                 "Chattel Paper" shall mean any and all "chattel paper," as
         such term is defined in the Uniform Commercial Code, now owned or
         hereafter acquired by the Borrower, wherever located.

                 "Documents" shall mean any and all "documents", as such term
         is defined in the Uniform Commercial Code, now owned or hereafter
         acquired by the Borrower, wherever located, including without
         limitation each bill of lading, dock warrant, dock receipt, warehouse
         receipt or order for the delivery of goods, and also any other
         document which in the regular course of business or financing is
         treated as adequately evidencing that the person in possession of it
         is entitled to receive, hold and dispose of the document and the goods
         it covers.

                 "General Intangibles" shall mean any and all "general
         intangibles," as such term is defined in the Uniform Commercial Code,
         now owned or hereafter acquired by the Borrower, including without
         limitation all contracts, undertakings, or agreements (including
         without limitation any and all contracts and agreements with any and
         all contractors, sub-contractors and architects with respect to any
         Property) in or under which the Borrower may now or hereafter have any
         right (other than any right evidenced by Chattel Paper, Documents or
         Instruments), title or interest, including without limitation any
         agreements relating to the terms of payment or the terms of
         performance of any Account.




                                      2
<PAGE>   6
                 "Holders" shall have the meaning specified in the first
         paragraph of this Security Agreement.

                 "Instruments" shall mean any and all "instruments", as such
         term is defined in the Uniform Commercial Code, now owned or hereafter
         acquired by the Borrower, wherever located, including without
         limitation all certificated securities, all certificates of deposit,
         and all notes and other, without limitation, evidences of
         indebtedness, other than instruments that constitute, or are a part of
         a group of writings that constitute, Chattel Paper.

                 "Investment Property" shall mean any and all "investment
         property," as such term is defined in the Uniform Commercial Code, now
         owned or hereafter acquired by the Borrower, wherever located.

                 "Lenders" shall have the meaning specified in the first
         paragraph of this Security Agreement.

                 "Lessee" shall mean Guilford Pharmaceuticals Inc., a Delaware
         corporation, its successors, permitted assigns and permitted
         transferees.

                 "Obligations" shall mean any and all obligations of the
         Borrower, now existing or hereafter arising under the Credit
         Agreement, the Notes, the Trust Agreement, the Certificates and/or any
         other Operative Agreement.

                 (b)      Capitalized terms used but not otherwise defined in
         this Security Agreement shall have the respective meanings specified
         in the Credit Agreement or Appendix A to the Participation Agreement
         dated as of February 5, 1998 (as amended, modified, extended,
         supplemented, restated and/or replaced from time to time in accordance
         with the applicable provisions thereof, the "Participation Agreement")
         among Lessee, the Borrower, the Holders, the Lenders and the Bank, as
         agent for the Lenders and respecting the Security Documents, as the
         agent for the Lenders and the Holders, to the extent of their
         interests.

                 (c)      The rules of usage set forth in Appendix A to the
         Participation Agreement shall apply to this Security Agreement.

         2.      GRANT OF SECURITY INTEREST.

To secure payment of all the amounts advanced under the Credit Agreement in
connection with the Notes, all the amounts advanced or contributed under the
Trust Agreement in connection with the Certificates and all other amounts now
or hereafter owing to the Lenders, the Holders or the Agent thereunder or under
any other Operative Agreement, THE BORROWER HEREBY CONVEYS, GRANTS, ASSIGNS,
TRANSFERS, HYPOTHECATES, MORTGAGES AND SETS OVER TO THE AGENT FOR THE BENEFIT
OF THE SECURED PARTIES, A FIRST PRIORITY SECURITY INTEREST IN AND LIEN ON THE
TRUST ESTATE, WHETHER





                                      3
<PAGE>   7
NOW EXISTING OR HEREAFTER ACQUIRED INCLUDING WITHOUT LIMITATION THE FOLLOWING:

                          (a)     all right, title and interest of the Borrower
                 in and to the Operative Agreements now existing or hereafter
                 acquired by the Borrower (including without limitation all
                 rights to payment and indemnity rights of the Borrower under
                 the Participation Agreement) (all of the foregoing in this
                 paragraph (a) being referred to as the "Rights in Operative
                 Agreements");

                          (b)     all right, title and interest of the Borrower
                 in and to all of the Equipment;

                          (c)     all right, title and interest of the Borrower
                 in and to all of the Fixtures;

                          (d)     all the estate, right, title, claim or demand
                 whatsoever of the Borrower, in possession or expectancy, in
                 and to each Property, Fixture or Equipment or any part
                 thereof;

                          (e)     all right, title and interest of the Borrower
                 in and to all substitutes, modifications and replacements of,
                 and all additions, accessions and improvements to, the
                 Fixtures and Equipment, subsequently acquired or leased by the
                 Borrower or constructed, assembled or placed by the Borrower
                 on any Property, immediately upon such acquisition, lease,
                 construction, assembling or placement, and in each such case,
                 without any further conveyance, assignment or other act by the
                 Borrower;

                          (f)     all right, title and interest of the Borrower
                 in, to and under books and records relating to or used in
                 connection with the operation of one (1) or more Properties or
                 any part thereof; all rights of the Borrower to the payment of
                 money and all property; and all rights in and to any causes of
                 action or choices in action now or hereafter existing in favor
                 of the Borrower and all rights to any recoveries therefrom;

                          (g)     all right, title and interest of the Borrower
                 in and to all unearned premiums under insurance policies now
                 held or subsequently obtained by the Lessee relating to one
                 (1) or more Properties and the Borrower's interest in and to
                 all proceeds of any insurance policies maintained by or for
                 the benefit of the Borrower, including without limitation any
                 right to collect and receive such proceeds; and all awards and
                 other compensation, including without limitation the interest
                 payable thereon and any right to collect and receive the same,
                 made to the present or any subsequent owner of any Property
                 for the taking by eminent domain, condemnation or otherwise,
                 of all or any part of any Property or any easement or other
                 right therein;



                                      4
<PAGE>   8
                          (h)     all right, title and interest of the Borrower
                 in and to (i) all consents, licenses, certificates and other
                 governmental approvals relating to construction, completion,
                 use or operation of any Property or any part thereof and (ii)
                 all Plans and Specifications relating to any Property;

                          (i)     all right, title and interest of the Borrower
                 in and to all Rent and all other rents, payments, purchase
                 prices, receipts, revenues, issues and profits payable under
                 the Lease or pursuant to any other lease with respect to any
                 Property;

                          (j)     all right, title and interest of the Borrower
                 in and to all Instruments and Documents;

                          (k)     all right, title and interest of the Borrower
                 in and to all General Intangibles;

                          (l)     all right, title and interest of the Borrower
                 in and to all Chattel Paper (including without limitation all
                 rights under the Lease) and each Ground Lease;

                          (m)     all right, title and interest of the Borrower
                 in and to all money, cash or cash equivalent and bank
                 accounts;

                          (n)     all right, title and interest of the Borrower
                 in and to all Accounts;

                          (o)     all right, title and interest of the Borrower
                 in and to all proceeds of letters of credit issued in favor of
                 the Borrower in connection with any Property; and

                          (p)     all right, title and interest of the Borrower
                 in and to all proceeds, both cash and noncash, of any of the
                 foregoing.

         (All of the foregoing property and rights and interests now owned or
held or subsequently acquired by the Borrower and described in the foregoing
clauses (a) through (p) are collectively referred to as the "Trust Property").

         TO HAVE AND TO HOLD the Trust Property and the rights and privileges
hereby granted unto the Agent (for the benefit of the Lenders and the Holders)
its successors and assigns for the uses and purposes set forth, until all of
the obligations of the Borrower under the Operative Agreements are paid in
full; provided, that EXCLUDED from the Trust Property at all times and in all
respects shall be all Excepted Payments.





                                      5
<PAGE>   9
         3.      PAYMENT OF OBLIGATIONS.

The Borrower shall pay all Obligations in accordance with the terms of the
Credit Agreement, the Notes, the Trust Agreement, the Certificates and the
other Operative Agreements and perform each term to be performed by it under
the Credit Agreement, the Notes, the Trust Agreement, the Certificates and the
other Operative Agreements.

         4.      OTHER COVENANTS.

At any time and from time to time, upon the written request of the Agent, and
at the expense of the Borrower (with funds provided by the Lessee for such
purpose), the Borrower will promptly and duly execute and deliver such further
instruments and documents and take such further actions as the Agent reasonably
may request for the purposes of obtaining or preserving the full benefits of
this Security Agreement and of the rights and powers granted by this Security
Agreement.

         5.      DEFAULT; REMEDIES.

         (a)     If a Credit Agreement Event of Default has occurred and is
continuing:

                          (i)     the Agent, in addition to all other remedies
                 available at law or in equity, shall have the right forthwith
                 to enter upon any Property (or any other place where any
                 component of any Property is located at such time) without
                 charge, and take possession of all or any portion of the Trust
                 Property, and to re-let the Trust Property and receive the
                 rents, issues and profits thereof, to make repairs and to
                 apply said rentals and profits, after payment of all necessary
                 or proper charges and expenses, on account of the amounts
                 hereby secured (subject to the Excepted Payments); and

                          (ii)    the Agent, shall, as a matter of right, be
                 entitled to the appointment of a receiver for the Trust
                 Property, and the Borrower hereby consents to such appointment
                 and waives notice of any application therefor.

                 (b)      If a Credit Agreement Event of Default has occurred
         and is continuing, the Agent may proceed by an action at law, suit in
         equity or other appropriate proceeding, to protect and enforce its
         rights, whether for the foreclosure of the Lien of this Security
         Agreement, or for the specific performance of any agreement contained
         herein or for an injunction against the violation of any of the terms
         hereof.  The proceeds of any sale of any of the Trust Property shall
         be applied pursuant to Section 8.7 of the Participation Agreement.  In
         addition, the Agent may proceed under Section 11 hereof.

                 (c)      The Borrower hereby waives the benefit of all
         appraisement, valuation, stay, extension and redemption laws now or
         hereafter in force and all rights of marshalling in the event of any
         sale of the Trust Property or any portion thereof or interest therein.





                                      6
<PAGE>   10
                 (d)      Notwithstanding anything to the contrary in this
         Security Agreement, so long as no event of default on the part of
         Lessee under any Operative Agreement to which Lessee is a party shall
         exist which would entitle the Lessor to terminate the Lease, or if
         such an event of default shall exist, so long as Lessee's time to cure
         the default shall not have expired, the term of the Lease shall not be
         terminated or modified in any respect whatsoever and Lessee's right of
         possession to the Properties and its other rights arising out of the
         Lease will all be fully recognized and protected by the Agent and
         shall not be disturbed, canceled, terminated or otherwise affected by
         reason of this Security Agreement or any action or proceeding
         instituted by the Agent to enforce its rights under this Security
         Agreement, or any extension, renewal, consolidation or replacement of
         same, irrespective of whether Lessee shall have been joined in any
         action or proceeding.

         6.      REMEDIES NOT EXCLUSIVE.

The Agent shall be entitled to enforce payment of the indebtedness and
performance of the Obligations and to exercise all rights and powers under this
Security Agreement or under any of the other Operative Agreements or other
agreements or any laws now or hereafter in force, notwithstanding some or all
of the Obligations may now or hereafter be otherwise secured, whether by deed
of trust, mortgage, security agreement, pledge, Lien, assignment or otherwise.
Neither the acceptance of this Security Agreement nor its enforcement, shall
prejudice or in any manner affect the Agent's right to realize upon or enforce
any other security now or hereafter held by the Agent, it being agreed that the
Agent shall be entitled to enforce this Security Agreement and any other
security now or hereafter held by the Agent in such order and manner as the
Agent may determine in its absolute discretion.  No remedy conferred hereunder
or under any other Operative Agreement upon or reserved to the Agent is
intended to be exclusive of any other remedy herein or therein or by law
provided or permitted, but each shall be cumulative and shall be in addition to
every other remedy given hereunder or thereunder or now or hereafter existing
at law or in equity or by statute.  Every power or remedy given by any of the
Operative Agreements to the Agent or to which it may otherwise be entitled, may
be exercised, concurrently or independently, from time to time and as often as
may be deemed expedient by the Agent.  In no event shall the Agent, in the
exercise of the remedies provided in this Security Agreement (including without
limitation in connection with the assignment of Rents to the Agent, or the
appointment of a receiver and the entry of such receiver onto all or any part
of the Land), be deemed a "mortgagee in possession" or a "pledgee in
possession", and the Agent shall not in any way be made liable for any act,
either of commission or omission, in connection with the exercise of such
remedies.

         7.      PERFORMANCE BY THE AGENT OF THE BORROWER'S OBLIGATIONS.

If the Borrower fails to perform or comply with any of its agreements contained
herein the Agent, at its option, but without any obligation so to do, may
perform or comply, or otherwise cause performance or compliance, with such
agreement.  The expenses of the Agent incurred in connection with actions
undertaken as provided in this Section 7, together with interest thereon at a
rate per annum equal to the Overdue Rate, from the date of payment by the Agent
to the date




                                      7
<PAGE>   11
reimbursed by the Borrower, shall be payable by the Borrower (with funds
provided by the Lessee for such purpose) to the Agent on demand and constitutes
part of the Obligations secured hereby.

         8.      DUTY OF THE AGENT.

The Agent's sole duty with respect to the custody, safekeeping and physical
preservation of any Trust Property in its possession, under Section 9-207 of
the Uniform Commercial Code or otherwise, shall be to deal with it in the same
manner as the Agent deals with similar property for its own account.  Neither
the Agent, any Lender, any Holder nor any of their respective directors,
officers, employees, shareholders, partners or agents shall be liable for
failure to demand, collect or realize upon any of the Trust Property or for any
delay in doing so or shall be under any obligation to sell or otherwise dispose
of any Trust Property upon the request of the Borrower or any other Person or
to take any other action whatsoever with regard to the Trust Property or any
part thereof.

         9.      POWERS COUPLED WITH AN INTEREST.

All powers, authorizations and agencies contained in this Security Agreement
are coupled with an interest and are irrevocable until this Security Agreement
is terminated and the Liens created hereby are released.

         10.     EXECUTION OF FINANCING STATEMENTS.

Pursuant to Section 9-402 of the Uniform Commercial Code, the Borrower
authorizes the Agent at the expense of the Borrower (such amounts to be paid
with funds provided by the Lessee for such purpose) to file financing
statements with respect to the Trust Property under this Security Agreement
without the signature of the Borrower in such form and in such filing offices
as the Agent reasonably determines appropriate to perfect the security
interests of the Agent under this Security Agreement.  A carbon, photographic
or other reproduction of this Security Agreement shall be sufficient as a
financing statement for filing in any jurisdiction.  For purposes of such
financing statement, the Borrower shall be deemed to be the debtor, and the
Agent shall be deemed to be the secured party.  The address of the Borrower is
79 South Main Street, Salt Lake City, Utah 84111, Attention: Val T.  Orton,
Vice President, and the address of the Agent is First Union National Bank, c/o
First Union Capital Markets Group, DC-6, 301 South College Street, Charlotte,
North Carolina 28288-0166, Attention: Ms. Jane O. Hurley, Capital Markets
Services.

         11.     SECURITY AGREEMENT UNDER UNIFORM COMMERCIAL CODE.

                 (a)      It is the intention of the parties hereto that this
Security Agreement as it relates to matters of the grant, perfection and
priority of security interests the subject hereof, shall constitute a security
agreement within the meaning of the Uniform Commercial Code of the States in
which the Trust Property is located.  If a Credit Agreement Event of Default
shall occur, then in addition to having any other right or remedy available at
law or in equity, the Agent may proceed under the applicable Uniform Commercial
Code and exercise such rights and remedies




                                      8
<PAGE>   12
as may be provided to a secured party by such Uniform Commercial Code with
respect to all or any portion of the Trust Property which is personal property
(including without limitation taking possession of and selling such property).
If the Agent shall elect to proceed under the Uniform Commercial Code, then
thirty (30) days' prior written notice of sale of the personal property shall
be deemed reasonable notice and the reasonable expenses of retaking, holding,
preparing for sale, selling and the like incurred by the Agent shall include,
but not be limited to, reasonable attorneys' fees and legal expenses.  At the
Agent's request, the Borrower shall assemble such personal property and make it
available to the Agent at a place designated by the Agent which is reasonably
convenient to both parties.

                 (b)      The Borrower, upon request by the Agent from time to
time, shall execute, acknowledge and deliver to the Agent one (1) or more
separate security agreements, in form satisfactory to the Agent, covering all
or any part of the Trust Property and will further execute, acknowledge and
deliver, or cause to be executed, acknowledged and delivered, any financing
statement, affidavit, continuation statement or certificate or other document
as the Agent may request in order to perfect, preserve, maintain, continue or
extend the security interest under, and the priority of the Liens granted by,
this Security Agreement and such security instrument.  The Borrower further
agrees to pay to the Agent (with funds provided by the Lessee for such purpose)
on demand all costs and expenses incurred by the Agent in connection with the
preparation, execution, recording, filing and re-filing of any such document
and all reasonable costs and expenses of any record searches for financing
statements the Agent shall reasonably require.  The filing of any financing or
continuation statements in the records relating to personal property or
chattels shall not be construed as in any way impairing the right of the Agent
to proceed against any property encumbered by this Security Agreement.

         12.     AUTHORITY OF THE AGENT.

The Borrower acknowledges that the rights and responsibilities of the Agent
under this Security Agreement with respect to any action taken by the Agent or
the exercise or non-exercise by the Agent of any option, voting right, request,
judgment or other right or remedy provided for herein or resulting or arising
out of this Security Agreement shall be governed by the Credit Agreement and
Section 8.6 of the Participation Agreement and by such other agreements with
respect thereto as may exist from time to time (until such time as all amounts
due and owing to the Secured Parties and the Agent under the Operative
Agreements have been paid in full), but the Agent shall be conclusively
presumed to be acting as agent for the Secured Parties with full and valid
authority so to act or refrain from acting, and the Borrower shall be under no
obligation, or entitlement, to make any inquiry respecting such authority.

         13.     NOTICES.

All notices required or permitted to be given under this Security Agreement
shall be in writing and delivered as provided in Section 12.2 of the
Participation Agreement.




                                      9
<PAGE>   13
         14.     SEVERABILITY.

Any provision of this Security Agreement which is prohibited or unenforceable
shall be ineffective to the extent of such prohibition or unenforceability
without invalidating the remaining provisions hereof.

         15.     AMENDMENT IN WRITING; NO WAIVERS; CUMULATIVE REMEDIES.

                 (a)      None of the terms or provisions of this Security
Agreement may be waived, amended, supplemented or otherwise modified except in
accordance with the terms of Section 12.4 of the Participation Agreement.

                 (b)      No failure to exercise, nor any delay in exercising,
on the part of the Agent, any right, power or privilege hereunder shall operate
as a waiver thereof.  No single or partial exercise of any right, power or
privilege hereunder shall preclude any other or further exercise thereof or the
exercise of any other right, power or privilege.  A waiver by the Agent of any
right or remedy hereunder on any one (1) occasion shall not be construed as a
bar to any right or remedy which the Agent would otherwise have on any future
occasion.

                 (c)      The rights and remedies herein provided are
cumulative, may be exercised singly or concurrently and are not exclusive of
any other rights or remedies provided by law.

         16.     SECTION HEADINGS.

The section headings used in this Security Agreement are for convenience of
reference only and are not to affect the construction hereof or be taken into
consideration in the interpretation hereof.

         17.     SUCCESSORS AND ASSIGNS.

This Security Agreement shall be binding upon the successors of the Borrower,
and the Borrower shall not assign any of its rights or obligations hereunder or
with respect to any of the Trust Property without the prior written consent of
the Agent.  This Security Agreement shall inure to the benefit of the Agent,
the Lenders, the Holders and their respective successors and assigns, in
accordance with their respective interest herein.

         18.     THE BORROWER'S WAIVER OF RIGHTS.

Except as otherwise set forth herein, to the fullest extent permitted by law,
the Borrower waives the benefit of all laws now existing or that may
subsequently be enacted providing for (a) any appraisement before sale of any
portion of the Trust Property, (b) any extension of the time for the
enforcement of the collection of the indebtedness or the creation or extension
of a period of redemption from any sale made in collecting such debt and (c)
exemption of any portion of the Trust Property from attachment, levy or sale
under execution or exemption from civil process.  Except as otherwise set forth
herein, to the fullest extent the Borrower may do so, the Borrower




                                      10
<PAGE>   14
agrees that the Borrower will not at any time insist upon, plead, claim or take
the benefit or advantage of any law now or hereafter in force providing for any
appraisement, valuation, stay, exemption, extension or redemption, or requiring
foreclosure of this Security Agreement before exercising any other remedy
granted hereunder and the Borrower, for the Borrower and its successors and
assigns, and for any and all Persons ever claiming any interest in the Trust
Property, to the extent permitted by law, hereby waives and releases all rights
of redemption, valuation, appraisement, stay of execution, notice of election
to mature or declare due the whole of the Obligations and marshalling in the
event of foreclosure of the Liens hereby created.

         19.     GOVERNING LAW.

EXCEPT AS OTHERWISE EXPRESSLY PROVIDED IN SECTION 11(a) HEREOF, THIS SECURITY
AGREEMENT SHALL BE GOVERNED BY, AND CONSTRUED AND INTERPRETED IN ACCORDANCE
WITH, THE INTERNAL LAWS OF THE STATE OF MARYLAND.

         20.     OBLIGATIONS ARE WITHOUT RECOURSE.

The provisions of the Participation Agreement relating to limitations on
liability are hereby incorporated by reference herein, Mutatis Mutandis.

         21.     PARTIAL RELEASE; FULL RELEASE.

The Agent may release for such consideration as it may require any portion of
the Trust Property without (as to the remainder of the Trust Property) in any
way impairing or affecting the Lien, security interest and priority herein
provided for the Agent compared to any other Lien holder or secured party.
Further, the Agent shall execute and deliver to the Borrower such documents and
instruments as may be required to release the Lien and security interest
created by this Security Agreement with respect to the Properties as provided
in Section 8.8 of the Participation Agreement or to grant the easements and
permit the other matters provided for in Section 8.5 of the Participation
Agreement.

         22.     MISCELLANEOUS.

                 (a)      This Security Agreement is one (1) of the documents
which create Liens and security interests that secure payment and performance
of the Obligations.  The Agent, at its election, may commence or consolidate in
a single action all proceedings to realize upon all such Liens and security
interests.  The Borrower hereby waives (i) any objections to the commencement
or continuation of an action to foreclose the Lien of this Security Agreement
or exercise of any other remedies hereunder based on any action being
prosecuted or any judgment entered with respect to the Obligations or any Liens
or security interests that secure payment and performance of the Obligations
and (ii) any objections to the commencement of, continuation of, or entry of a
judgment in any such other action based on any action or judgment connected to
this Security Agreement.  In case of a foreclosure sale, the Trust Property may
be sold, at the Agent's election, in one (1) parcel or in more than one (1)
parcel and the Agent is specifically empowered




                                      11
<PAGE>   15
(without being required to do so, and in its sole and absolute discretion) to
cause successive sales of portions of the Trust Property to be held.

                 (b)      This Security Agreement may not be amended, waived,
discharged or terminated except in accordance with Section 12.4 of the
Participation Agreement.  Upon the prior written consent of the Majority
Secured Parties and unless such matter is a Unanimous Vote Matter, the Agent
may release any portion of the Trust Property or any other security, and grant
such extensions and indulgences in relation to the Obligations secured hereby
without in any manner affecting the priority of the Lien hereof on any part of
the Trust Property.

                 (c)      THE PROVISIONS OF THE PARTICIPATION AGREEMENT
RELATING TO SUBMISSION TO JURISDICTION, VENUE AND ARBITRATION ARE HEREBY
INCORPORATED BY REFERENCE HEREIN, MUTATIS MUTANDIS.

         23.     CONFLICTS WITH PARTICIPATION AGREEMENT.

Notwithstanding any other provision hereof, in the event of any conflict
between the terms of this Security Agreement and the Participation Agreement,
the terms of the Participation Agreement shall govern.

         24.     LESSEE AS A PARTY.

         LESSEE HAS EXECUTED THIS SECURITY AGREEMENT FOR THE SOLE PURPOSE OF
SUBJECTING TO THE SECURITY INTERESTS GRANTED HEREUNDER ALL OF ITS RIGHT, TITLE,
ESTATE AND INTEREST, IF ANY, IN AND TO THE TRUST PROPERTY TO SECURE ITS
OBLIGATIONS UNDER THE OPERATIVE AGREEMENTS.  ACCORDINGLY, LESSEE HEREBY GRANTS
TO THE AGENT (FOR THE BENEFIT OF THE LENDERS AND THE HOLDERS) A SECURITY
INTEREST IN AND TO ALL OF ITS RIGHT, TITLE, ESTATE AND INTEREST, IF ANY, IN AND
TO THE TRUST PROPERTY (TO THE EXTENT LESSEE HAS ANY RIGHT, TITLE OR INTEREST
THEREIN AND WITHOUT REGARD TO ANY LANGUAGE IN SECTION 2 OR THE DEFINITION OF
"TRUST PROPERTY' OR ANY DEFINITION OF ANY ITEM CONSTITUTING THE TRUST PROPERTY
WHICH OTHERWISE WOULD LIMIT THE TRUST PROPERTY TO THE RIGHT, TITLE AND INTEREST
OF THE BORROWER THEREIN) TO SECURE ITS OBLIGATIONS UNDER THE OPERATIVE
AGREEMENTS.  LESSEE ACKNOWLEDGES AND AGREES THAT, SUBJECT TO SECTION 5(D) OF
THIS SECURITY AGREEMENT, UPON THE OCCURRENCE OF AN EVENT OF DEFAULT, THE AGENT
SHALL HAVE THE RIGHT TO EXERCISE ANY OR ALL OF ITS REMEDIES HEREUNDER AS
AGAINST ANY SUCH RIGHT, TITLE, ESTATE OR INTEREST OF LESSEE IN OR TO THE TRUST
PROPERTY.




                                      12
<PAGE>   16
         IN WITNESS WHEREOF, each of the undersigned have caused the Security
Agreement to be duly executed and delivered as of the date first above written.


                           FIRST SECURITY BANK, NATIONAL
                           ASSOCIATION, not individually, but solely as the
                           Owner Trustee under the Guilford Real Estate Trust
                           1998-1


                           By: /s/ Brett R. King
                               -----------------------------------------------
                           Name:    Brett R. King
                                 ---------------------------------------------
                           Title:   Assistant Vice President
                                  --------------------------------------------



                           FIRST UNION NATIONAL BANK, as the Agent
                           for the Lenders and the Holders


                           By: /s/ Louis E. Flori
                               -----------------------------------------------
                           Name:    Louis E. Flori
                                 ---------------------------------------------
                           Title:   Vice President
                                  --------------------------------------------




Accepted and Agreed to:

GUILFORD PHARMACEUTICALS INC.


By: /s/ Andrew R. Jordan
    -----------------------------------------------
Name:    Andrew R. Jordan
      ---------------------------------------------
Title:   Senior Vice President & Chief Financial
       ------------------------------------------
          Officer
         --------