LOAN AND SECURITY AGREEMENT

         THIS LOAN AND SECURITY AGREEMENT (this "Agreement") is made as of March
25, 1998 by and between ARE-4757 NEXUS CENTRE, LLC, a Delaware limited liability
company  ("Lender"),  and MATRIX  PHARMACEUTICAL,  INC., a Delaware  corporation
("Borrower"), with respect to the following Recitals:


                                 R E C I T A L S

                  A. Borrower is the owner of the  Improvements  (as hereinafter
defined).

                  B.  Borrower  desires  to borrow  from  Lender,  and Lender is
willing  to loan to  Borrower,  the  principal  amount  of Six  Million  Dollars
($6,000,000.00) for the purposes and upon the terms set forth herein.


                                A G R E E M E N T

         NOW THEREFORE,  in consideration  of the foregoing,  and for other good
and  valuable  consideration,  the receipt and  sufficiency  of which are hereby
acknowledged, the parties hereto agree as follows:


                                65535RT65535CLE 1
                               GENERAL DEFINITIONS

         When used herein, the following initially  capitalized terms shall have
the following meanings:

         "Affiliate"  means, with respect to any Person,  any other Person which
controls,  is  controlled  by, or is under  common  control  with the  Person in
question.  For the purposes of the  foregoing  definition,  "controls"  (and its
correlative  terms  "controlled  by" and  "under  common  control  with")  means
possession  by the  applicable  Person  of the  power to  direct  or  cause  the
direction of the management and policies thereof,  whether through the ownership
of voting securities, by contract, or otherwise.

         "Agreement" means this Loan and Security  Agreement,  together with all
supplements, amendments and modifications hereto and all extensions and renewals
hereof.

         "Attorneys' Fees,"  "Attorneys' Fees and Costs,"  "attorneys' fees" and
"attorneys'  fees and


<PAGE>


costs"  mean the  reasonable  fees and  expenses  of counsel  to the  applicable
parties  to the  Loan  Documents,  which  may  include  printing,  photostating,
duplicating, facsimilating, messengering, filing and other expenses, air freight
charges, and fees billed for law clerks,  paralegals,  librarians and others not
admitted  to the  bar  but  performing  services  under  the  supervision  of an
attorney.  The terms "attorneys' fees" or "attorneys' fees and costs" shall also
include, without limitation, all such fees and expenses incurred with respect to
appeals, arbitrations,  bankruptcy proceedings and any post-judgment proceedings
to collect any judgment,  and whether or not any action or proceeding is brought
with respect to the matter for which, such fees and expenses were incurred,  but
shall not  include any such fees or expenses  incurred  in  connection  with the
preparation and negotiation of the Lease or the Purchase Agreement. The recovery
of  post-judgment  fees,  costs and  expenses is separate  and several and shall
survive the merger of the applicable Loan Documents into any judgment.

         "Bankruptcy  Code"  means  Titles  7,  11 or 13 of the  U.S.  Code,  as
applicable, or any similar federal or state laws for the relief of debtors, each
as hereafter amended.

         "Business Day" means any day other than a Saturday,  a Sunday,  a legal
holiday under the laws of the State of  California or a day on which  commercial
banks in such state are  authorized  or  required  by law or other  governmental
action to be closed.

         "Closing  Date"  means  the  date of the  closing  of the  Loan and the
recordation of the Deed of Trust in the Official  Records of the County in which
the Project is situated.

         "Contractual  Obligation"  as applied to any Person means any provision
of any  instrument,  document  or  security  issued  by  that  Person  or of any
indenture,  mortgage, deed of trust, contract,  undertaking,  agreement or other
instrument to which that Person is a party or by which any of its  properties is
bound or to which it or any of its properties is subject.

         "Deed of Trust" means that certain Deed of Trust and Fixture  Filing of
even date herewith executed by Borrower,  as trustor, to Chicago Title Insurance
Company,  as trustee,  and naming Lender, as beneficiary,  to be recorded on the
Closing  Date in the  Official  Records  of the  County in which the  Project is
situated.

         "Default  Interest  Rate" means an interest  rate that is the lesser of
(i) eighteen percent (18%) per annum or (ii) the maximum rate permitted by law.

         "Environmental Laws" is defined in the Lease.

         "Event of Default" means any of the events specified in Section 6.1.

                                       2

<PAGE>


         "Formation Documents" means (a) as to any corporation,  its articles of
incorporation and bylaws, (b) as to any limited partnership,  its Certificate of
Limited Partnership and partnership agreement, (c) as to any general partnership
or joint venture, its Statement of Partnership and partnership agreement, (d) as
to any limited  liability  company,  its articles or certificate of organization
and  operating  agreement,  and (e) as to any trust,  its trust  agreement and a
certification of the current trustees  thereof,  each of the foregoing  together
with all supplements, amendments and modifications.

         "General  Partner" or "general  partner" means the general  partners of
the partnership in question,  together with any constituent  general partners of
such general partners.

         "Governmental  Agency"  means any  federal,  state,  municipal or other
governmental or quasi-governmental court, agency, authority or district.

         "Hazardous Substances" is defined in the Lease.

         "Improvements"  means all fixtures and  interior  improvements  located
within the  manufacturing  suites  cross-hatched  on Exhibit B-1 attached hereto
(which  manufacturing suites are located within the buildings upon the Project),
including,  without  limitation,  the  fixtures and  improvements  to the extent
constituting  real  property and located  therein and  identified on Exhibit B-2
attached hereto,  together with all present and future attachments,  accessions,
replacements, substitutions and additions thereto or therefor, and together with
all  insurance  proceeds  relating to the loss of or damage to such  fixtures or
improvements  which Borrower receives from any policy of insurance  covering any
of the foregoing property now or hereafter acquired by Borrower.

         "Indemnitees"  means,   collectively  and  individually,   Lender,  its
Affiliates and its and their directors, officers, agents, employees,  successors
and assigns.

         "Laws"  means  all  federal,   state,   county,   municipal  and  other
governmental and quasi-governmental  statutes, laws, rules, orders, regulations,
ordinances,  judgments, decrees and injunctions affecting Borrower's interest in
the  Project or  Borrower's  occupancy,  operation,  ownership  or use  thereof,
whether now or hereafter enacted and in force including, without limitation, the
Americans With Disabilities  Act, 42 U.S.C.  ss.ss.  12101-12213  (1991) and all
Environmental   Laws,  any  zoning  or  other  land  use  entitlements  and  any
requirements  which may require  repairs,  modifications or alterations in or to
the  Project,  all  Permits  and all  covenants,  agreements,  restrictions  and
encumbrances  running  in favor of any  Person,  contained  in any  instruments,
either of record or known to Borrower, at any time in force affecting Borrower's
interest in the Project or  Borrower's  occupancy,  operation,  ownership or use
thereof.

                                       3

<PAGE>


         "Lease"  means that certain  Lease of even date herewith by and between
Lender,  as landlord,  and Borrower,  as tenant,  pursuant to which Borrower has
leased from Lender a portion of the Project.

         "Lien" means any mortgage,  deed of trust,  pledge,  security interest,
encumbrance,  lien, charge or claim of any kind (including any agreement to give
any of the foregoing,  any conditional sale or other title retention  agreement,
any lease in the nature  thereof,  and/or the filing of or agreement to give any
financing  statement under the Uniform Commercial Code of any jurisdiction) with
respect to  Borrower's  interest in the Project or the Personal  Property or any
portion thereof or interest therein.

         "Loan"  means the loan to Borrower as more  particularly  described  in
Section 2.1.

         "Loan Documents" means the documents  described in Section 3.1, and all
other documents  securing,  or executed in connection  with, the Loan,  together
with all renewals,  substitutions,  extensions,  modifications  or  replacements
thereof.

         "Maturity  Date"  means the date set  forth in the Note upon  which the
entire  principal  amount of the Loan,  together with all other amounts owing to
Lender under the Loan Documents, shall be due and payable.

         "Note" means that certain Secured Promissory Note of even date herewith
in the  principal  amount of Six  Million  Dollars  ($6,000,000.00)  executed by
Borrower, as maker, in favor of Lender, as holder,  substantially in the form of
Exhibit D attached hereto, and any and all modifications,  extensions,  renewals
and replacements thereof.

         "Permits" means all permits, licenses, franchises, approvals, variances
and  land  use  entitlements  necessary  for  Borrower's  occupancy,  operation,
ownership and use of the Project.

         "Permitted  Liens"  means  the  liens and  encumbrances  identified  on
Exhibit E attached hereto.

         "Person"  means and includes  natural  persons,  corporations,  limited
liability  companies,  limited  liability  partnerships,  limited  partnerships,
general  partnerships,  joint stock  companies,  joint  ventures,  associations,
companies,  trusts, banks, trust companies,  land trusts,  business trusts, real
estate investment trusts or other organizations,  whether or not legal entities,
and governments and agencies and political subdivisions thereof.

                                       4

<PAGE>


         "Personal  Property" means all personal property described on Exhibit C
attached hereto,  together with all present and future attachments,  accessions,
replacements, substitutions and additions thereto or therefor, and together with
all  insurance  proceeds  relating  to the loss of or  damage  to such  personal
property  which Borrower  receives from any policy of insurance  covering any of
the foregoing property now or hereafter acquired by Borrower; provided, however,
that "Personal  Property" shall not include any of Borrower's  inventory or work
in process.

         "Potential  Default" means a condition or event which,  with the giving
of notice or  passage of time,  or both,  would  constitute  an Event of Default
under any of the Loan Documents or the Lease.

         "Principals" means individually and collectively  Borrower, its general
partners,  managing members and major shareholders,  as applicable,  and each of
such  parties'   constituent  general  partners,   managing  members  and  major
shareholders, as applicable.

         "Project"  means that  certain  parcel of land  described  on Exhibit A
attached hereto.

         "Project  Documents"  means (a) all  agreements to which  Borrower is a
party now or  hereafter  in effect with any  contractor,  architect or engineer,
including, without limitation, any design architect,  landscape architect, civil
engineer,  electrical  engineer,   environmental  engineer,  soils  engineer  or
mechanical engineer,  in connection with Borrower's interest in the Project; (b)
all other  agreements  to which  Borrower is a party now or  hereafter in effect
with any property manager or broker with respect to the management,  subleasing,
or operation of Borrower's  interest in the Project;  (c) all as-built plans and
specifications  and  surveys  for  the  Project;  (d) all  Permits;  and (e) all
renewals, substitutions, extensions, modifications or replacements of any of the
foregoing.

         "Purchase Agreement" means that certain Purchase and Sale Agreement and
Joint  Escrow  Instructions,  dated  as of  February  3,  1998,  by and  between
Borrower,  as seller,  and  Alexandria  Real Estate  Equities,  Inc., a Maryland
corporation, as buyer.

         "Related Parties" means Borrower, Principals, any Affiliate of Borrower
or Principals,  any  partnership of which Borrower or any Principal is a general
partner, and any limited liability company of which Borrower or any Principal is
a manager or managing member.

         "Secured Obligations" is defined in the Deed of Trust.

         "Tax Identification  Number" means Borrower's  employer  identification
number or social security number, which is 94-2957068.

                                       5

<PAGE>


         "Title  Policy"  means an  American  Land  Title  Association  Extended
Coverage Policy of Title Insurance (1970 version, amended 10/17/70 only), issued
by Chicago Title Insurance  Company ("Title  Company"),  insuring Lender that on
the Closing  Date the Deed of Trust is a valid  first lien on the  Improvements,
and is in  the  amount  of  the  Loan.  The  Title  Policy  shall  contain  such
endorsements  as Lender  reasonably  requires  and shall be subject only to such
exceptions  to coverage  as  approved by Lender in writing  prior to the Closing
Date.


                                65535RT65535CLE 2
                                   LOAN TERMS

         2.1      Loan and Disbursements of Loan Proceeds.

                  Subject to the terms and conditions of this Agreement,  and in
reliance upon the  representations  and  warranties of Borrower set forth in the
Loan Documents, Lender agrees to make to Borrower, and Borrower agrees to accept
from Lender,  a loan (the "Loan") in the principal amount of Six Million Dollars
($6,000,000.00).  The Loan proceeds  shall be disbursed by Lender on the Closing
Date.

         2.2      Evidence of Indebtedness and Maturity.

                  Borrower shall execute and deliver to Lender, on or before the
Closing  Date,  the Note  evidencing  the  Loan.  Borrower  agrees  to repay the
indebtedness  evidenced by the Note in accordance with the terms thereof and the
terms  hereof.  The  outstanding  principal  balance of the Loan,  together with
accrued and unpaid  interest  thereon and all other amounts  payable by Borrower
under the Loan Documents shall be due and payable on the Maturity Date.

         2.3      Interest Rate.

                  The Loan shall bear  interest at the rate per annum  specified
in the Note.


                                65535RT65535CLE 3
                               CONDITIONS TO LOAN

         3.1      Condition Precedent to Closing of Loan.

                  As a condition  precedent to Lender's  obligation to close the
Loan and disburse any Loan proceeds, on or before the Closing Date Borrower must
satisfy and fulfill each of the following  conditions  precedent to closing,  to
the satisfaction of Lender:

                                       6

<PAGE>


                  A. Loan  Documents.  Borrower  shall  deliver  to  Lender  the
following  documents,  each duly  executed and  acknowledged  by a notary public
where necessary, and in form and substance satisfactory to Lender:

                           (i)      This Agreement;
                           (ii)     The Lease;
                           (iii)    The Note;
                           (iv)     The Deed of Trust; and
                           (v)      A  California   UCC-1  Financing   Statement
relating to the Personal  Property and the  Improvements (to the extent that the
Improvements or any portion thereof or proceeds  therefrom  constitute  personal
property),  to be filed with the  California  Secretary of State,  together with
UCC-1 Financing Statements for such other States as are required by Lender.

                  B.  Title.   The  Title  Company  shall  be  irrevocably   and
unconditionally  committed  to issue the Title  Policy to Lender in the form and
with such endorsements required by Lender.

                  C. Opinion.  Borrower's  counsel shall be committed to deliver
to Lender an opinion  regarding the  enforceability  and the due  authorization,
execution  and delivery of this  Agreement,  the Note and the Deed of Trust,  in
form and substance,  and containing such assumptions and qualifications,  as may
be reasonably satisfactory to Lender's counsel.

                  D.   Truth   of    Representations    and   Warranties.    The
representations  and  warranties of Borrower  contained  herein and in the other
Loan Documents,  the Lease and the Purchase Agreement shall be true, correct and
complete in all material respects on the Closing Date.

                  E. No  Default.  As of the Closing  Date,  no event shall have
occurred or would result from the funding of the Loan that would  constitute  an
Event of Default or a Potential Default.


                                65535RT65535CLE 4
                               SECURITY AGREEMENT

         4.1      Grant of Security Interest.

                  As security  for the payment  and  performance  of the Secured
Obligations,  subject  to the  terms  and  conditions  hereof,  Borrower  hereby
assigns, transfers and grants to Lender, and there is hereby created in favor of
Lender, a security  interest under the California  Commercial

                                       7

<PAGE>


Code in and to the Personal  Property and the  Improvements  (to the extent that
the  Improvements  or any  portion  thereof  or  proceeds  therefrom  constitute
personal property), whether now owned or hereafter acquired, and in all proceeds
thereof (and proceeds of proceeds).  This Agreement shall  constitute a security
agreement  pursuant  to the  California  Commercial  Code  with  respect  to the
Personal  Property and the  Improvements (to the extent that the Improvements or
any portion thereof or proceeds therefrom  constitute personal property) and the
proceeds  thereof,  with Borrower the "Debtor" and Lender the "Secured Party" as
such terms are used therein.

         4.2      Representations, Agreements and Covenants Regarding Personal
                  Property and Improvements.

                  In order to induce  Lender to enter  into this  Agreement  and
make the Loan, Borrower represents, warrants and covenants as follows:

                  A. Except for the security interest in favor of Lender and the
Permitted  Liens,  Borrower  is, and as to any of the  Personal  Property or the
Improvements  acquired  after the date  hereof  will be,  the sole owner of such
Personal  Property  and  Improvements,  free  from any  adverse  lien,  security
interest,  or adverse claim of any kind whatsoever.  Borrower will notify Lender
of and will defend such Personal  Property and  Improvements  against all claims
and demands of all persons at any time claiming any interest therein.

                  B.   Borrower   will  keep  the  Personal   Property  and  the
Improvements in good condition and repair, and will not misuse,  abuse, allow to
deteriorate, waste or destroy such Personal Property or Improvements or any part
thereof,  except for ordinary wear and tear  resulting  from normal and expected
use in the  ordinary  course of  Borrower's  business,  which  shall be promptly
replaced by  Borrower  with  property of similar  nature and of equal or greater
value unless obsolete.

                  C.  Borrower will not,  without the prior  written  consent of
Lender,  sell, offer to sell or otherwise  transfer,  exchange or dispose of the
Personal  Property or the  Improvements  or any  interest  therein,  unless such
Personal  Property or  Improvements  are being replaced by collateral of similar
nature  and  of  equal  or  greater  value.  If  the  Personal  Property  or the
Improvements or any part thereof are sold, transferred,  exchanged, or otherwise
disposed of (either with or without the written consent of Lender), the security
interest of Lender shall extend to the proceeds of such sale, transfer, exchange
or other  disposition and Borrower will hold such proceeds in a separate account
for Lender's  benefit and will, at Lender's  request,  transfer such proceeds to
Lender.

                  D. The tangible  Personal  Property  will be kept on or at the
Project and  Borrower  will not,  without the prior  written  consent of Lender,
remove  the  Personal  Property  or

                                       8

<PAGE>


the  Improvements  (to the extent that the  Improvements  or any portion thereof
constitute personal property) therefrom or otherwise sever the Improvements from
the  Project  except  such  portions  or  items  of such  Personal  Property  or
Improvements which are consumed or worn out in ordinary usage or due to casualty
not caused by Borrower,  all of which shall be promptly  replaced by Borrower as
provided in Section 4.2(B).

                  E. Borrower will  immediately  notify Lender in writing of any
change in its place of business  or the  adoption or change of any trade name or
fictitious business name, and will, within ten (10) days after Lender's request,
execute any additional  financing  statements or other  certificates  reasonably
requested by Lender to reflect such change.

                  F. The Personal Property and the Improvements are not and will
not be used or bought for personal, family or household purposes.

                  G.  Borrower  shall  immediately  notify  Lender  of any claim
against the  Personal  Property or the  Improvements  adverse to the interest of
Borrower or Lender therein.

                  H. Lender may examine and inspect the  Personal  Property  and
the Improvements at any reasonable time, wherever located, upon reasonable prior
notice to Borrower.

         4.3      Affixed Collateral.

                  The  inclusion  in Section  4.1 of any  Personal  Property  or
Improvements  (to the  extent  that  the  Improvements  or any  portion  thereof
constitute personal property) which may now be or hereafter become affixed or in
any manner  attached to the Project  shall be without  prejudice to any claim at
any time made by Lender that such Personal  Property or Improvements are or have
become a part of or an accession to the Project.

         4.4      Further Security Agreements.

                  Borrower agrees to take such actions and, within ten (10) days
after  Lender's  request,  to  execute,  deliver  and file  and/or  record  such
documents, agreements and financing statements as may be reasonably necessary to
evidence  the  security  interest  set forth in Section  4.1, to  establish  the
priority thereof and to carry out the intent and purpose of this Article 4.

         4.5      Borrower's License.

                  Notwithstanding  anything to the contrary  herein,  as long as
there shall exist no Event of Default  hereunder,  Borrower shall have the right
under a license hereby  granted by

                                       9

<PAGE>


Lender to collect,  but not prior to accrual, all cash proceeds arising from (i)
Borrower's ownership of the Personal Property and Improvements,  (ii) Borrower's
leasehold interest in the Project as a result of Borrower's leasing or licensing
thereof and (iii) the  ordinary  course of  Borrower's  business in the Project;
provided that,  except as otherwise  provided  herein,  Borrower shall not sell,
encumber,  pledge or otherwise  dispose of the Personal Property or Improvements
without the Lender's prior written  approval,  which may be withheld in Lender's
sole discretion.


                                65535RT65535CLE 5
                    BORROWER'S REPRESENTATIONS AND WARRANTIES

         As an inducement to Lender to execute this Agreement and make the Loan,
Borrower represents and warrants to Lender the truth and accuracy of the matters
set forth in this Article 5.

         5.1      Organization, Power, Good Standing, and Business.

                  Borrower is a corporation duly formed, validly existing and in
good  standing  under the Laws of the State of Delaware and, if formed under the
Laws of a jurisdiction other than the State of California,  has registered to do
business  and is in good  standing  under the Laws of the  State of  California.
Borrower has the full power and authority to own and operate its properties,  to
carry on its business as now conducted, to enter into each Loan Document, and to
carry out the transactions contemplated hereby and thereby. Borrower does not do
business  under any trade name or  fictitious  business  name other than "Matrix
Pharmaceutical".  Borrower has  delivered  to Lender true,  correct and complete
copies of its Formation  Documents and such  Formation  Documents  have not been
amended or modified except  pursuant to agreements  delivered to Lender prior to
the date hereof.

         5.2      Authorization of Borrowing, etc.

                  A.  Authorization  of Borrowing.  The execution,  delivery and
performance of the Loan Documents and the issuance,  delivery and payment of the
Note have been duly authorized by all necessary action of Borrower.

                  B. No Conflict.  The  execution,  delivery and  performance by
Borrower of each  applicable  Loan  Document do not and will not (i) violate any
Law applicable to any such Person,  the Formation  Documents of any such Person,
or any  order,  judgment  or decree of any  court or other  Governmental  Agency
binding  on any such  Person;  (ii)  conflict  with,  result  in a breach  of or
constitute  (with the giving of notice or the passage of time or both) a default
under any Contractual  Obligation of any such Person; (iii) result in or require
the creation or imposition

                                       10

<PAGE>


of any Lien of any  nature on  Borrower's  properties  or assets  other than the
Liens in favor of Lender under the Loan Documents;  or (iv) require any approval
or consent of any Person under any Contractual Obligation of Borrower.

                  C.  Governmental   Consents.   The  execution,   delivery  and
performance by Borrower of each  applicable  Loan Document does not and will not
require any  registration  with,  consent or approval of, or notice to, or other
action to, with or by, any Governmental Agency or other Person.

                  D. Binding  Obligation.  The Note and the other Loan Documents
are the legally valid and binding  obligations of Borrower,  enforceable against
Borrower in accordance with their respective terms, except as enforcement may be
limited by bankruptcy,  insolvency,  reorganization,  moratorium or similar laws
relating to or limiting creditors' rights generally.

         5.3      Actions.

                  There is no action, suit, proceeding or arbitration, before or
by any  Governmental  Agency or other  Person,  pending or, to  Borrower's  best
knowledge,  threatened against or affecting  Borrower,  any of the Principals or
any  properties  or rights of  Borrower  or any of the  Principals,  which might
adversely  affect  Lender's  rights or remedies  under the Loan  Documents,  the
business,  assets,  operations  or financial  condition of any such party or its
ability to perform  its  obligations  under the Loan  Documents.  As of the date
hereof, there are no outstanding  judgments against the Related Parties or their
property.

         5.4      Financial Position.

                  A.  Financial   Information.   All  financial  statements  and
financial data delivered to Lender in connection  with the Loan and/or  relating
to Borrower and the  Principals  are true,  correct and complete in all material
respects and accurately present the financial position of such parties as of the
date thereof.  No material adverse change has occurred in the financial position
disclosed by any financial statements or financial data delivered to Lender.

                  B. Bankruptcy and Insolvency.  Neither Borrower nor any of the
Related  Parties  has filed or been the subject of any  bankruptcy,  insolvency,
reorganization,  dissolution  or similar  proceeding or any  proceeding  for the
appointment  of a receiver or trustee for all or any  substantial  part of their
respective  property.  Neither  Borrower  nor  any of the  Related  Parties  has
admitted in writing its  inability to pay its debts when due, made an assignment
for the benefit of creditors or taken other similar action.

                  C. Other  Borrowing.  Except for the Loan, no borrowings  have
been made by

                                       11

<PAGE>


Borrower which are secured by the  Improvements  or which might give rise to any
Lien other than the Liens created by the Loan Documents.

         5.5      Liens.

                  Borrower is the sole owner of the  Improvements  free from any
adverse Liens,  except for Liens and other rights in favor of Lender and for the
Permitted  Liens.  Borrower  has  paid in  full  all  contractors,  materialmen,
laborers, architects or other such Persons hired by Borrower to perform services
or work with respect to the  Improvements  and all  statutory  lien periods have
expired with respect to any such services or work. No previous assignment, sale,
pledge,  encumbrance or other  hypothecation  of the  Improvements has been made
(except  for  Permitted  Liens and  pledges  and  encumbrances  which  have been
released  in  full  prior  to the  date  hereof  or  will  be  released  in full
concurrently with the funding of the Loan).

         5.6      Defects.

                  To the best of  Borrower's  knowledge,  there are no  defects,
facts or conditions  affecting  the  Improvements  or any portion  thereof which
would make the  Improvements  unsuitable  for their intended  operation,  use or
sale.

         5.7      No Defaults.

                  No  Potential  Default or Event of Default  exists  under this
Agreement, the Lease, the Purchase Agreement or any of the other Loan Documents.
To the best of  Borrower's  knowledge,  no default by Borrower  exists under any
Contractual  Obligation which would have a material adverse effect on Borrower's
ability to repay the Loan or to perform  its  obligations  under any of the Loan
Documents or the Lease.

         5.8      Disclosure.

                  No  representation  or warranty of Borrower  contained in this
Agreement,  the Lease, the Purchase  Agreement or any Loan Document contains any
untrue  statement of a material fact or omits to state a material fact necessary
in order to make the statements contained herein or therein not misleading.


                                65535RT65535CLE 6
                              BORROWER'S COVENANTS

                  Borrower  covenants  and agrees  that,  until the Loan and all
other  amounts owing

                                       12

<PAGE>


to Lender  under  the Loan  Documents  have  been  paid in full and all  Secured
Obligations have been satisfied,  Borrower shall perform all of the covenants in
this Article 6.

         6.1      No Liens.

                  Borrower  shall not  permit  any Lien to be made or filed with
respect to the  Improvements  except for Liens which are being contested in good
faith,  for which adequate  reserves have been established and which do not pose
an imminent risk to the Improvements or the Personal Property. Borrower shall be
the sole owner of the  Improvements,  free from any  adverse  Liens,  except for
Permitted Liens and Liens in favor of Lender.  Borrower shall not assign,  sell,
pledge,   encumber  or  otherwise   hypothecate   all  or  any  portion  of  the
Improvements.

         6.2      Compliance with Laws.

                  Borrower  shall comply with all Laws  applicable  to Borrower,
its property,  Borrower's  interest in the Project,  the Personal Property,  the
Improvements and/or Borrower's occupancy, operation, ownership or use thereof.

         6.3      Inspection.

                  During  normal  business  hours  and upon  reasonable  advance
notice,  Borrower  shall permit  Lender and any Person  designated  by Lender to
visit and inspect the Improvements.

         6.4      Environmental Matters.

                  Borrower  shall  comply  and cause all  persons  entering  the
Project to comply with all  Environmental  Laws and all of Borrower's  covenants
relating to Hazardous Substances set forth in the Lease.

         6.5      Insurance Requirements.

                  Borrower  shall procure and maintain,  or cause to be procured
and  maintained,  at  all  times  until  the  repayment  of  the  Loan  and  the
satisfaction  of the  Secured  Obligations,  policies of  insurance  in form and
amounts satisfying the requirements of the Lease.

         6.6      Notice of Proceeding.

                  Borrower  will  promptly  notify  Lender of any action,  suit,
proceeding  or  arbitration  (including,  without  limitation,  any  judicial or
nonjudicial  foreclosure  proceeding,  any

                                       13

<PAGE>


voluntary  or  involuntary  bankruptcy  proceeding  or any  proceeding  for  the
appointment  of a  receiver),  commenced or  threatened  against  Borrower,  the
Improvements,  Borrowers'  interest  in the  Project or any  portion  thereof or
interest  therein.  Borrower  shall  deliver to Lender copies of all notices and
other information in connection with any action, suit, proceeding or arbitration
promptly upon receipt or transmittal thereof.

         6.7      Representations and Warranties.

                  Until  repayment  of the Loan and all other  amounts  owing to
Lender  under the Loan  Documents  and the  satisfaction  of all  other  Secured
Obligations,  the  representations  and  warranties set forth in Article 5 shall
remain true and correct.

         6.8      Financial Reporting.

                  Borrower  shall  deliver  to Lender  (a)  within  thirty  days
following  the end of each  fiscal  quarter of  Borrower,  Borrower's  unaudited
financial  statements and accompanying  notes for such quarter and year to date,
certified  by Borrower to be true,  correct and  complete in all  respects,  (b)
within sixty days following the end of each fiscal year of Borrower,  Borrower's
audited financial  statements and accompanying notes for such year, certified by
Borrower  to be true,  correct  and  complete  in all  respects,  (c) within ten
business days following the occurrence of any event or circumstance  which could
reasonably  be expected  to have a material  adverse  affect upon the  business,
prospects or  financial  condition of Borrower,  notice  thereof  together  with
Borrower's plans to address such event or circumstance,  (d) promptly  following
the  preparation  or  submission  of such items,  copies of all 10-K's,  10-Q's,
8-K's, proxy statements,  annual reports,  Business Plans and other materials as
may be reasonably  requested by Buyer  pertaining to the financial  condition of
Seller.


         6.9      Further Assurances.

                  Borrower  shall execute and deliver from time to time,  within
ten (10)  business  days after any request by Lender,  any and all  instruments,
agreements  and  documents and shall take such other action as may be reasonably
necessary or  desirable in the opinion of Lender to maintain,  perfect or insure
Lender's  security  provided  for  herein  and  in  the  other  Loan  Documents,
including,  without limitation,  the execution of UCC-1 renewal statements,  the
execution of such  amendments to the Deed of Trust and the other Loan  Documents
and the delivery of such  endorsements to the Title Policy,  all as Lender shall
reasonably require, and to the extent that such actions are required as a result
of Borrower's activities or an Event of Default, Borrower shall pay all fees and
expenses  (including  reasonable  attorney's fees) related  thereto,  and in all

                                       14

<PAGE>


other circumstances Lender shall be responsible for its own fees and expenses.


                                65535RT65535CLE 7
                           EVENTS OF DEFAULT; REMEDIES

         7.1      Events of Default.

                  The occurrence of any of the following events shall constitute
an Event of Default under this Agreement and the other Loan Documents:

                  A. Failure to Make  Payments When Due.  Borrower's  failure to
pay any principal,  interest or other monies due under this Agreement, the Lease
or any of the other Loan  Documents  within three (3) days after written  notice
that such amount is due (provided, however, that Lender shall have no obligation
to give Borrower written notice more than two times in any twelve month period).

                  B.  Breach of  Covenants.  Borrower's  failure  to  perform or
comply with any other term,  obligation or condition contained in this Agreement
or any of the other Loan  Documents,  within thirty (30) days after the delivery
of written notice from Lender of such failure;  provided that if such default is
not reasonably  capable of being cured within such thirty (30) day period,  such
failure shall not  constitute an Event of Default so long as Borrower  commences
the cure of such  default  within  such  thirty  (30) day period and  diligently
prosecutes  such cure to  completion  within  sixty (60) days after such written
notice from Lender.

                  C.  Breach  of   Warranty.   Any   representation,   warranty,
certification  or other  statement made by Borrower  herein or in any other Loan
Document or in any statement or certificate at any time given by Borrower or any
of the  Principals  to Lender in  writing in  connection  with the Loan shall be
materially false or misleading.

                  D.       Involuntary Bankruptcy; Appointment of Receiver, etc.

                  (i) A court having proper jurisdiction shall enter a decree or
order for relief  with  respect to  Borrower  in an  involuntary  case under the
Bankruptcy  Code or any applicable  bankruptcy,  insolvency or other similar law
now or hereafter in effect, which decree or order is not stayed within seven (7)
days after entry and  dismissed  within ninety (90) days after the entry of such
order; or any other similar relief shall be granted under any applicable federal
or state law; or

                  (ii) An involuntary case is commenced  against Borrower or any
of the Principals, under any applicable bankruptcy,  insolvency or other similar
law now or  hereafter  in

                                       15

<PAGE>


effect;  or a decree  or order of a court  for the  appointment  of a  receiver,
liquidator,  sequestrator,  trustee,  custodian or other officer  having similar
powers over Borrower or any of the Principals or over all or a substantial  part
of their respective property,  shall be entered; or the involuntary  appointment
of an interim  receiver,  trustee or other  custodian  of Borrower or any of the
Principals,  for all or a substantial part of their respective property;  or the
issuance of a warrant of attachment,  execution or similar  process  against any
substantial  part  of  the  respective  property  of  Borrower  or  any  of  the
Principals, and the continuance of any such event in this clause (ii) for ninety
(90) days unless dismissed or discharged.

                  E.       Voluntary Bankruptcy; Appointment of Receiver, etc.

                  (i) Borrower or any of the Principals  shall have an order for
relief  entered  with  respect to them or  commence a  voluntary  case under the
Bankruptcy  Code or any applicable  bankruptcy,  insolvency or other similar law
now or hereafter in effect, or shall consent to the entry of an order for relief
in an  involuntary  case,  or to the  conversion  of an  involuntary  case  to a
voluntary  case,  under any such law, or shall consent to the  appointment of or
taking  possession  by a  receiver,  trustee  or  other  custodian  for all or a
substantial part of their respective property;  the making by Borrower or any of
the Principals of any assignment for the benefit of creditors; or

                  (ii)  The  inability  or  failure  of  Borrower  or any of the
Principals,  or the admission by Borrower or any of the Principals in writing of
its inability, to pay their respective debts as such debts become due.

                  F. Lien Priority.  Lender fails to have a legal, valid binding
and  enforceable  first  priority  Lien on the  Improvements  and  the  Personal
Property subject only to Permitted Liens.

                  G. Unapproved Transfers. Any transfer of the Improvements, the
Personal Property,  Borrower's interest in the Lease or any interest in Borrower
occurs without Lender's prior written consent or otherwise in accordance with of
the Loan Documents.

                  H. Failure to Maintain  Insurance.  Borrower fails to maintain
or cause to be maintained the insurance coverage required by Section 6.5.

                  I. Other Liens. Without limiting the provisions of Section 6.1
of this  Agreement,  Borrower  defaults  under  any Lien  (other  than the Liens
created by the Loan Documents) or foreclosure or other proceedings are commenced
to enforce any Lien (other than the Liens created by the Loan Documents).

                                       16

<PAGE>


                  J. Other Loan Documents. The occurrence of an Event of Default
under  any of the Loan  Documents  other  than this  Agreement  or the Lease (as
"Event of Default" is defined therein).

                  K.  Lease.  The  occurrence  of an Event of Default  under the
Lease (as "Event of Default" is defined therein).

         7.2      General Remedies.

                  Notwithstanding  anything to the contrary  contained herein or
in any of the other Loan Documents,  upon the occurrence of any Event of Default
(i) at the option of Lender  upon  written  notice to  Borrower  as to  Sections
6.1(A)  through (C) and (F) through (I),  and  automatically  without  notice to
Borrower as to Sections 7.1(D), (E), (J) and (K), the unpaid principal amount of
the Loan,  all accrued and unpaid  interest  and all other  Secured  Obligations
shall become immediately due and payable, without presentment,  demand, protest,
further  notice  or other  requirements  of any kind,  all of which  are  hereby
expressly waived by Borrower,  (ii) Lender shall have the rights and remedies of
a  secured  party  under the  California  Commercial  Code,  and under any other
applicable  law,  (iii)  Lender  may  pursue  all of  its  rights  and  remedies
hereunder,  under the other  Loan  Documents,  at law,  in equity or  otherwise,
including without limitation, obtaining the appointment of a receiver, provided,
however,  that if Lender  seeks to exercise  its right of sale under the Deed of
Trust,  the purchaser of the Improvements  (including  Lender or its affiliates)
shall have the right to cause Borrower to enter into a lease (and Borrower shall
be deemed to have  elected  to enter  into such  lease) of the  Improvements  to
Borrower  in  accordance  with the rent  payment  as set forth in Article 9 (iv)
Lender may pursue any remedies  available to it pursuant to  California  Code of
Civil Procedure  Section 726.5,  (v) all outstanding  indebtedness and all other
amounts  owing to Lender  under the Loan  Documents  shall bear  interest at the
Default  Interest  Rate,  and (vi) Lender  shall have no further  obligation  to
disburse Loan proceeds to Borrower.

         7.3      Specific Performance.

                  Upon  the  occurrence  of an  Event  of  Default,  Lender  may
commence  and  maintain  an action in any court of  competent  jurisdiction  for
specific  performance of any of the covenants and agreements contained herein or
in any of the other Loan  Documents,  may obtain  the aid and  direction  of the
court in the performance of any of the covenants and agreements contained herein
or therein, and may obtain orders or decrees directing the same and, in the case
of any sale under the Deed of Trust, directing, confirming or approving Lender's
or the trustee's actions.

                                65535RT65535CLE 8

                                       17

<PAGE>


                            MISCELLANEOUS PROVISIONS

         8.1      Nonforeign Status.

                  Section 1445 of the Internal  Revenue Code of 1985, as amended
(the  "Internal  Revenue  Code")  and  Sections  18662,  18668  and 18669 of the
California  Revenue and Taxation Code (the "California Tax Code") provide that a
transferee of a U.S. real property interest, or California property interest, as
the case may be, must withhold tax under the circumstances described therein. To
inform Lender that the  withholding  of tax will not be required in the event of
the disposition of the Improvements  pursuant to the terms of the Deed of Trust,
Borrower hereby certifies, under penalty of perjury, that: (a) Borrower is not a
foreign corporation,  foreign  partnership,  foreign trust or foreign estate, as
those terms are defined in the Internal Revenue Code and/or  California Tax Code
and the regulations  promulgated  thereunder;  and (b) Borrower's U.S.  employer
identification number is the Tax Identification Number; (c) Borrower's principal
place of business is at the address set forth in Section 8.10,  and (d) Borrower
is qualified to do business in the State of California.  Lender may disclose the
contents  of this  Section  8.1 to the  Internal  Revenue  Service  or any other
Governmental Agency and Borrower acknowledges that any false statement contained
herein could be punished by fine,  imprisonment or both.  Borrower covenants and
agrees to execute further  certificates,  which shall be signed under penalty of
perjury,   as  Lender  shall   reasonably   require  in   connection   with  the
certifications set forth herein. The covenant set forth herein shall survive the
foreclosure  of the lien of the Deed of Trust or acceptance of a deed in lieu or
in aid thereof.

         8.2      Assignments and Participations in Loan and Note.

                  Lender may assign its  rights  and  delegate  its  obligations
under this  Agreement or any of the other Loan Documents and further may assign,
or sell  participations in, all or any part of the Loan, the Loan Documents,  or
any other interest herein or in the Note to any Person, all without notice to or
the consent of Borrower.  To the extent of any such assignment,  Lender shall be
relieved of its obligations with respect to the Loan and the assignee shall have
the  same  rights,  benefits  and  obligations  as it  would  if it were  Lender
hereunder  and a  holder  of  the  Note.  Lender  may  furnish  any  information
(including,   without   limitation,   financial   information)   concerning  the
Improvements, the Project, Borrower, Principals and any of their assets to third
parties from time to time for legitimate business purposes  (provided,  however,
that Lender shall use reasonable efforts to maintain the  confidentiality of any
information provided by Borrower of a proprietary nature).

         8.3      Expenses.

                                       18

<PAGE>


                  Borrower  agrees to pay,  within ten (10) days after demand by
Lender,  all  reasonable  costs and  expenses  (including,  without  limitation,
reasonable attorneys' fees and costs, fees of any consultants,  and fees for any
environmental audits, appraisal, inspections or other review required by Lender)
incurred  by Lender in  connection  with the  enforcement  of any of the Secured
Obligations,  the  enforcement of any of Lender's  rights and remedies under the
Loan  Documents,  the  collection of any payments  owing to Lender  hereunder or
under any of the other  Loan  Documents,  whether  or not such  enforcement  and
collection includes the filing of a lawsuit, or the retaking, holding, preparing
for sale or selling the  Improvements  or the  Personal  Property or any portion
thereof or any interest therein. Such costs and expenses shall include,  without
limitation,  Lender's  reasonable  attorneys' fees and costs,  including without
limitation  attorneys'  fees and costs incurred by Lender in connection with any
insolvency, bankruptcy, reorganization, arrangement or other similar proceedings
involving Borrower or any of the Principals which in any way affect the exercise
by Lender of its  rights  and  remedies  hereunder,  under any of the other Loan
Documents, at law or in equity.

         8.4      Joint and Several Obligations.

                  The liability of Borrower  under this Agreement and under each
of the other Loan Documents shall be joint and several.

         8.5      Indemnity.

                  In addition to the duties of indemnification  set forth in the
Lease,  Borrower  hereby  indemnifies and agrees to defend and hold harmless the
Indemnitees  from and  against any and all  expenses,  loss,  claims,  damage or
liability, including, without limitation, architects', engineers' and attorneys'
fees and  costs,  to the  extent  arising  from:  (a) any use,  nonuse,  misuse,
possession,  occupation,  alteration,  operation,  maintenance  or management by
Borrower of the Improvements or the Personal  Property or any part thereof;  (b)
any negligence or willful act or omission on the part of Borrower or its agents,
contractors,  servants,  employees,  licensees  or invitees;  (c) any  accident,
injury  (including  death) or damage to any person or  property  relating to the
use, nonuse, misuse, possession,  occupation, alteration, operation, maintenance
or  management  of the  Improvements  or the  Personal  Property;  (d)  any  tax
attributable  to the  execution,  delivery,  filing or  recording of the Deed of
Trust,  the Note or the other Loan Documents;  (e) any default under the Note or
the other Loan Documents,  or (f) any claim by or liability to any contractor or
subcontractor  performing work or any party  supplying  materials to Borrower in
connection with the Improvements or the Personal Property.

         8.6      Waiver of Offset.

                                       19

<PAGE>


                  All  sums  payable  by  Borrower  pursuant  to any of the Loan
Documents shall be paid without notice, demand, counterclaim,  setoff, deduction
or  defense  and  without  abatement,   suspension,   deferment,  diminution  or
reduction,  and the  obligations  and  liabilities  of  Borrower  under the Loan
Documents shall in no way be released,  discharged or otherwise affected (except
as expressly  provided in the Loan Documents) by reason of: (a) any damage to or
destruction of the  Improvements  or any  condemnation  or eminent domain action
affecting  the  Improvements  or  any  part  thereof;  (b)  any  restriction  or
prevention  of  or  interference  by  any  third  party  with  any  use  of  the
Improvements  or any part thereof;  (c) any title defect or  encumbrance  or any
eviction  from the Project or any part thereof by title  paramount or otherwise;
(d)  any  bankruptcy,  insolvency,   reorganization,   composition,  adjustment,
dissolution,  liquidation or other like  proceeding  relating to Lender,  or any
action  taken  with  respect  to any of the Loan  Documents  by any  trustee  or
receiver of Lender, or by any court, in any such proceeding; (e) any claim which
Borrower  has or might have  against  Lender;  (f) any default or failure on the
part of Lender to perform or comply with any of the terms hereof or of any other
agreement with Borrower; or (g) any other occurrence whatsoever, whether similar
or dissimilar  to the  foregoing;  whether or not Borrower  shall have notice or
knowledge of any of the foregoing. Except as expressly provided herein, Borrower
waives all rights now or  hereafter  conferred  by statute or  otherwise  to any
abatement, suspension,  deferment, diminution or reduction of any of the Secured
Obligations.

         8.7      Amendments and Waivers.

                  This  Agreement  and the  other  Loan  Documents  may  only be
modified  in  writing  signed by all of the  parties  hereto or thereto or their
respective  successors and assigns. No waiver of any provision of this Agreement
or of any of the other Loan  Documents,  or consent to any departure by Borrower
therefrom,  shall in any event be  effective  without the written  agreement  of
Lender.  Any waiver or consent shall be effective only in the specific  instance
and for the  specific  purpose  for  which it was  given.  Except  as  expressly
required by the terms of the Loan Documents,  no notice to or demand on Borrower
in any case shall entitle  Borrower to any other or further  notice or demand in
similar or other circumstances.

         8.8      WAIVER OF JURY TRIAL.

                  BORROWER  AND LENDER EACH HEREBY  KNOWINGLY,  VOLUNTARILY  AND
INTENTIONALLY WAIVE ANY RIGHT THEY MAY HAVE TO A TRIAL BY JURY IN RESPECT TO ANY
TORT OR CONTRACT  LITIGATION BASED HEREON OR ON ANY OF THE OTHER LOAN DOCUMENTS,
OR  ARISING  OUT OF,  UNDER OR IN  CONJUNCTION  WITH THE NOTE,  ANY  OTHER  LOAN
DOCUMENT,  OR ANY COURSE OF  CONDUCT,  COURSE OF  DEALING,  STATEMENTS  (WHETHER
VERBAL OR WRITTEN) OR ACTIONS OF EITHER PARTY IN CONNECTION THEREWITH.

                                       20

<PAGE>


         8.9      Submission of Loan Documents.

                  The  submission  of this  Agreement  or any of the other  Loan
Documents  to Borrower or its agents or attorneys  for review or signature  does
not constitute a commitment by Lender to make the Loan to Borrower, and the Loan
Documents  shall  have no  binding  force or effect  unless  and until  they are
executed  and  delivered by Borrower  and Lender and all of the  conditions  set
forth in Section 3.1 have been satisfied.

         8.10     Notices.

                  Any notice,  or other document or demand required or permitted
under  this  Agreement  or any of the other Loan  Documents  shall be in writing
addressed  to the  appropriate  address  set  forth  below  and  shall be deemed
delivered upon the earliest of (a) actual receipt,  (b) confirmation of delivery
by telecopy  (provided that a copy is subsequently  delivered by regular mail or
overnight  delivery),  (c) the next  Business  Day  after  the date when sent by
recognized overnight courier, or (c) the second Business Day after the date when
sent by registered or certified mail, postage prepaid.  Any party may, from time
to time,  change the address at which such written notice or other  documents or
demands are to be sent, by giving the other party written  notice of such change
in the manner hereinabove provided.

         To Borrower:               Matrix Pharmaceutical, Inc.
                                    4757 Nexus Centre Drive
                                    San Diego, California 92121
                                    Attention: Mr. Ron Lucas
                                    Telephone: (619) 824-5121
                                    Facsimile: (619) 643-5699

         With A Copy To:            Brobeck, Phlegar & Harrison
                                    550 W. "C" Street, Suite 1300
                                    San Diego, California 92101
                                    Attention: Scott Biel, Esq.
                                    Telephone: (619) 699-0289
                                    Facsimile: (619) 234-3848

         To Lender:                 ARE-4757 Nexus Centre, LLC
                                    135 N. Los Robles Avenue, Suite 250
                                    Pasadena, California 91101
                                    Attention:  Corporate Secretary

                                       21

<PAGE>


                                    Telephone:  (626) 578-0777
                                    Facsimile:  (626) 578-0770

         With A Copy to:            Alexandria Real Estate Equities, Inc.
                                    11440 West Bernardo Court, Suite 170
                                    San Diego, California  92127
                                    Attention:  Gary A. Kreitzer, Esq.
                                    Telephone:  (619) 592-6801
                                    Facsimile:    (619) 592-6814

         With A Copy To:            Skadden, Arps, Slate, Meagher & Flom LLP
                                    300 South Grand Avenue, Suite 3400
                                    Los Angeles, California  90071
                                    Attention:  George M. Eshaghian, Esq.
                                    Telephone:  (213) 687-5215
                                    Facsimile:  (213) 687-5600

         8.11     Survival of Warranties and Certain Agreements.

                  All agreements,  indemnities,  representations  and warranties
made herein and in the other Loan  Documents  shall  survive the  execution  and
delivery of this  Agreement,  the making of the Loan hereunder and the execution
and  delivery  of the Note.  All  representations  and  warranties  made in this
Agreement or in any of the other Loan  Documents  shall further  survive any and
all investigations and inquiries made by Lender,  shall remain true, correct and
complete in all material  respects and shall remain  continuing  obligations  so
long  as  any  portion  of  the  Secured   Obligations  remains  outstanding  or
unsatisfied.  Notwithstanding  anything  in this  Agreement  or the  other  Loan
Documents or implied by law to the contrary, any indemnities made by Borrower in
the Loan Documents  shall survive the payment of the Loan, the  satisfaction  of
the Secured  Obligations,  and/or the termination of this Agreement or the other
Loan Documents.

         8.12     Failure or Indulgence Not Waiver; Remedies Cumulative.

                  No failure or delay on the part of Lender or any holder of the
Note or  portion  thereof  in the  exercise  of any  power,  right or  privilege
hereunder  or under the Note shall  impair such power,  right or privilege or be
construed to be a waiver of any default or acquiescence  therein,  nor shall any
single or partial exercise of any such power,  right or privilege preclude other
or further  exercise  thereof or of any other  right,  power or  privilege.  All
rights and remedies  existing  under this Agreement and the other Loan Documents
are

                                       22

<PAGE>


separate,  distinct  and  cumulative  to,  and not  exclusive  of, any rights or
remedies otherwise  available at law or in equity. No act of Lender under any of
the Loan  Documents  shall be construed as an election to proceed  under any one
provision to the exclusion of any other provision,  notwithstanding  anything in
the Loan Documents to the contrary.  Borrower  expressly waives all right to the
benefit  of any  statute  of  limitations  and  any  moratorium,  reinstatement,
marshaling, forbearance, extension, redemption, or appraisement now or hereafter
provided by federal or state law, as a defense to any demand against Borrower to
the fullest extent permitted by law.

         8.13     Survival of Obligations Upon Termination of Agreement.

                  No  termination  or  cancellation   (regardless  of  cause  or
procedure) of this Agreement or any of the other Loan Documents shall in any way
affect or impair the powers,  obligations,  duties,  rights,  and liabilities of
Borrower or Lender  relating to (a) any  transaction or event occurring prior to
such termination or cancellation,  or (b) any of the  undertakings,  agreements,
covenants,  indemnities,  warranties and  representations  of Borrower or Lender
contained in this Agreement or any of the other Loan Documents.

         8.14     Disbursements in Excess of Loan Amount.

                  In the event  the total  disbursements  by Lender  exceed  the
amount of the Loan set forth herein,  the total of all  disbursements  shall, to
the extent permitted by the laws of the State of California,  constitute part of
the  Secured  Obligations  and be  secured  by the Deed of Trust and other  Loan
Documents.  All other sums expended by Lender  pursuant to this Agreement or any
of the other Loan  Documents  shall be deemed to have been paid to Borrower  and
shall be secured by the Loan Documents.

         8.15     Severability.

                  If any  term  of  this  Agreement  or any  of the  other  Loan
Documents or the application  thereof to any person or circumstances,  shall, to
any extent,  be invalid or  unenforceable,  the  remainder of this  Agreement or
other Loan Document or the application of such term to persons or  circumstances
other  than  those as to which it is  invalid  or  unenforceable,  shall  not be
affected  thereby,  and each term of this Agreement or other Loan Document shall
be valid and enforceable to the fullest extent.

         8.16     Rules of Construction.

                  Where the identity of the parties to this  Agreement or any of
the other Loan

                                       23

<PAGE>


Documents  or the  circumstances  make  it  appropriate,  the  masculine  gender
includes the  feminine  and/or  neuter,  and the  singular  number  includes the
plural.  Article  and  Section  headings  in this  Agreement  and the other Loan
Documents  are  included  for  convenience  of  reference  only  and  shall  not
constitute a part of this  Agreement or such other Loan  Documents for any other
purpose or be given any substantive  effect.  The recitals to this Agreement and
to each of the other Loan Documents are incorporated herein and therein and made
a part hereof and thereof.

         8.17     Applicable Law.

                  This Agreement and the other Loan Documents  shall be governed
by, and  construed  and enforced in  accordance  with,  the laws of the State of
California.

         8.18     Successors and Assigns.

                  This  Agreement  shall be binding  upon and shall inure to the
benefit of the parties hereto and their respective successors an assigns. Except
as expressly provided in the Loan Documents (including,  without limitation, the
Lease), Borrower's rights and obligations or any interest hereunder or under any
of the other Loan Documents may not be assigned,  including without  limitation,
assigned  for security  purposes,  without the prior  written  consent of Lender
which may be  withheld  in  Lender's  sole  discretion,  and any such  purported
assignment  shall be null and void ab initio.  As used herein,  and in the other
Loan Documents, "Lender" (or similar references to the lender) shall include all
holders  of the  Note,  including,  without  limitation,  pledgees  of the Note,
whether or not named herein or therein.  In exercising  any rights  hereunder or
under any of the other Loan Documents or taking any actions  provided for herein
or  therein,  Lender  may act  through  its  employees,  agents  or  independent
contractors authorized by Lender.

         8.19     Disclosure of Information.

                  Borrower hereby  acknowledges and agrees that upon the request
of any partner,  member or  shareholder of Borrower,  as applicable,  Lender may
disclose to such party any information (including, without limitation, financial
information) relating to the Loan and Borrower's  performance of its obligations
under the Loan Documents.  Borrower hereby  indemnifies and agrees to defend and
hold  harmless  the  Indemnitees  from and against any and all  expenses,  loss,
claims, damage or liability, including, without limitation,  attorneys' fees and
costs,  arising by reason of any  disclosure of information by Lender under this
Section 8.19.

                                       24

<PAGE>


         8.20     Counterparts.

                  This Agreement and the other Loan Documents may be executed in
any number of  counterparts,  each of which when so executed and delivered shall
be deemed to be an original and all of which  counterparts  taken together shall
constitute  but one and the  same  instrument.  Signature  and,  if  applicable,
acknowledgment  pages may be detached  from the  counterparts  and attached to a
single copy of the applicable  document to physically  form one document,  which
may be recorded if applicable.

         8.21     Entire Agreement.

                  The Loan Documents set forth the entire understanding  between
Borrower  and  Lender  relative  to the Loan and the same  supersede  all  prior
agreements and understandings relating to the subject matter hereof or thereof.

         8.22     Inconsistencies.

                  In the event it is  impossible to  simultaneously  comply with
the terms of this Agreement and any of the terms of any other Loan Document, the
terms of this Agreement  shall control over any  inconsistent  term of any other
Loan Document.

         8.23     Time is of the Essence.

                  Time is  strictly  of the  essence of this  Agreement  and the
other Loan Documents.

         8.24     No Third Party Beneficiaries.

                  This  Agreement  and the  other  Loan  Documents  are made and
entered into for the sole  protection  and benefit of the parties  hereto,  and,
except as provided in Section  8.18, no other person or entity shall be a direct
or indirect beneficiary of, or shall have any direct or indirect cause of action
or claim in connection with, this Agreement or any of the other Loan Documents.

                                65535RT65535CLE 9
                               PUT RIGHT & OPTION

         9.1  Borrower  shall have the right at any time  prior to the  Maturity
Date,  upon  delivery of written  evidence  reasonably  satisfactory  to Lender,
together with such supporting

                                       25

<PAGE>


documentation  and  certificates  as  Lender  may in its good  faith  discretion
require,  that Borrower has completed strategic alliances or joint ventures with
a  cumulative  value in  excess of  $10,000,000,  as  measured  by  initial  and
milestone  payments  received by Borrower  from  unaffiliated  joint  venture or
alliance  partners,  and provided that no Event of Default or Potential  Default
exists,  to cause  Lender to  purchase  an  undivided  one-half  interest in the
Improvements  in exchange for one-half of the outstanding  principal  balance of
the Loan (up to  $3,000,000).  In the event that Borrower  exercises such right,
Borrower shall, as a condition precedent to the transfer, execute and deliver to
Lender such instruments,  agreements and title endorsements (including,  without
limitation,  deeds,  assignments and other  conveyance  documents) as Lender may
reasonably  request  in  order  to  convey  good  and  marketable  title  to the
Improvements  to be conveyed to Lender,  together with an amendment to the Lease
in form and substance  acceptable to Lender in its discretion  whereby  Borrower
shall  lease  back  from  Lender  the  Improvements  so  conveyed  and the  rent
thereunder shall be increased by $330,000 per annum,  payable in the same manner
(and subject to the same adjustments) as Basic Annual Rent thereunder.

         9.2 Borrower shall have right at any time  subsequent to the sale of an
undivided  one-half  interest in the  Improvements to Lender pursuant to Section
9.1 above but prior to the Maturity  Date, and provided that no Event of Default
or  Potential  Default  exists,  upon  delivery of written  evidence  reasonably
satisfactory  to  Lender,  together  with  such  supporting   documentation  and
certificates as Lender may in its good faith discretion require, that either (a)
Borrower has completed  strategic  alliances or joint ventures with a cumulative
value in excess of  $15,000,000,  as measured by initial and milestone  payments
received by Borrower from unaffiliated  joint venture or alliance  partners,  or
(b) Borrower's net sales from products for the immediately preceding fiscal year
(as reported in Borrower's  most recent public  filings with the  Securities and
Exchange Commission) were no less than $10,000,000,  to cause Lender to purchase
the  remaining  interest  in the  Improvements  in  exchange  for the  remaining
outstanding principal balance of the Loan (up to $3,000,000).  In the event that
Borrower exercises such right,  Borrower shall, as a condition  precedent to the
transfer,  execute and deliver to Lender such instruments,  agreements and title
endorsements  (including,  without  limitation,  deeds,  assignments  and  other
conveyance  documents) as Lender may reasonably  request in order to convey good
and marketable title to the Improvements to be conveyed to Lender, together with
an  amendment  to the Lease in form and  substance  acceptable  to Lender in its
discretion  whereby  Borrower shall lease back from Lender the  Improvements  so
conveyed and the rent  thereunder  shall be increased by an additional  $330,000
per annum,  payable in the same manner (and subject to the same  adjustments) as
Basic Annual Rent thereunder.

         9.3 Lender shall have the right at any time prior to the Maturity Date,
upon

                                       26

<PAGE>


delivery of written notice to Borrower, to purchase the Improvements in exchange
for the outstanding  principal  balance of the Loan (up to  $6,000,000).  In the
event that Lender  exercises  such right,  Borrower shall execute and deliver to
Lender such instruments,  agreements and title endorsements (including,  without
limitation,  deeds,  assignments and other  conveyance  documents) as Lender may
reasonably  request  in  order  to  convey  good  and  marketable  title  to the
Improvements  to Lender,  together  with an  amendment  to the Lease in form and
substance  acceptable to Lender in its discretion  whereby  Borrower shall lease
back from Lender the  Improvements so conveyed and the rent thereunder  shall be
increased by $660,000 per annum,  payable in the same manner (and subject to the
same adjustments) as Basic Annual Rent thereunder.

                                       27

<PAGE>


                  IN WITNESS WHEREOF,  this Agreement has been duly executed and
delivered Borrower and Lender as of the date first above written.

                                           BORROWER:

                                           MATRIX PHARMACEUTICAL, INC.,
                                           a Delaware corporation



                                           By:  /s/ Ronald P. Lucas
                                                --------------------------------
                                              Its:  Vice President of Operations
                                                    ----------------------------


                                           By:
                                                --------------------------------
                                              Its:
                                                    ----------------------------


                                           LENDER:

                                           ARE-4757 NEXUS CENTRE, LLC,
                                           a Delaware limited liability company

                                           By:  ALEXANDRIA REAL ESTATE EQUITIES,
                                                L.P., a Delaware limited 
                                                partnership, managing member

                                                By: ARE-QRS CORP., a Maryland
                                                    corporation, general partner


                                                  By:  /s/ Peter Nelson
                                                       -------------------------
                                                   Its:  Chief Financial Officer
                                                        ------------------------


<PAGE>


                                    EXHIBIT A

                             Description of Project


That  certain  real  property  located in the City of San  Diego,  County of San
Diego, State of California,  having a street address of 4757 Nexus Centre Drive,
more particularly described as follows:


         Parcel 1 of  Parcel  Map  17892 in the City and  County  of San  Diego,
         according  to Map filed in the  Office of the County  Recorder  of said
         county on August 6, 1997.

                                      A-1

<PAGE>


                                   EXHIBIT B-1

                            Manufacturing Suite Plans

                                     B-1-1

<PAGE>


                                   EXHIBIT B-2

                DESCRIPTION OF EXCLUDED IMPROVEMENTS AND FIXTURES


Production Equipment Design Requirements

MEP Design-TKG
MEP Design-TKG
Architectural Design-WHL
Civil Design-Latitude 33
Structural Design-Hope Eng.


Production Equipment

WFI System including tanks, pumps, valve, controls
RQ/DI Water Equipment
Air Handler No. 12
Cargocaire Unit
Pure Steam Generator Drip Legs


Production Equipment Contractor Work (Labor, Overhead & Profit)

Work Performed by Contractor
Site Management
Site Requirements
Contractor Fee


Production  Equipment   Subcontractor  Work  (Installation,   Material  &  Labor
Requirements)

Site Utilities
Doors/Frames/Hardware
Drywall/Taping & Painting
Flooring/Walls-Mipolam, VCT, Sheet Vinyl
Stainless Steel Casework
Kolpak Cold Box w/Honeywell Trueline Recorder
HVAC
Plumbing Systems
Process Utilities
Process Controls
Electrical


Production Facility Scope of Work Changes

Boroscoping



<PAGE>


                                    EXHIBIT C

                        Description of Personal Property

         All of Borrower's right, title and interest, now or hereafter acquired,
in and to the following;  provided, however, that none of the following shall be
construed to include any of those items of personal  property  listed on Exhibit
B-2 to this Agreement, or the proceeds therefrom:

         (a) All personal property  (including,  without limitation,  all goods,
supplies,  equipment,   furniture,   furnishings,   machinery  and  construction
materials)  which  Borrower  now or hereafter  owns or in which  Borrower now or
hereafter  acquires an interest or right,  which are now or hereafter located on
or affixed to the Project and are used or useful in the maintenance or operation
of any of the  Improvements,  together with and all books,  records,  leases and
other  documents,  of  whatever  kind  or  character,  relating  to  any  of the
foregoing;

         (b) All fees,  income and rents which,  after the date hereof and while
any portion of the Secured  Obligations  remains unpaid,  may accrue from any of
the personal property described in paragraph (a) of this Exhibit C, or which may
be  received  or  receivable  by Borrower  from any  hiring,  letting,  leasing,
subhiring, subletting, or subleasing therefor;

         (d)  All  other   intangible   property  and  rights  relating  to  the
Improvements or Borrower's  operation thereof, or used in connection  therewith,
including but not limited to all governmental permits owned by Borrower relating
to  construction of the  Improvements,  and all permits,  licenses,  franchises,
approvals and variances  relating in any way to, or to the operation,  ownership
and use of, the Improvements;

         (e) All judgments,  claims,  settlements of claims and causes of action
under any legal proceeding  relating to Borrower's  interest in the Improvements
or Borrower's use, occupancy or operation thereof;

         (f) All proceeds from sale or disposition of the Personal Property;

         (g)  Borrower's  rights  under  all  insurance  policies  covering  the
Improvements  or  any of the  Personal  Property  (whether  or not  Borrower  is
required to maintain such insurance under the terms of the Loan Documents),  and
all proceeds, loss payments and premium refunds payable regarding the same;

         (h) All reserves,  deferred payments,  deposits,  refunds, cost savings
and payments

                                      C-1

<PAGE>


of any kind relating to the construction of any Improvements;

         (i) All causes of action,  claims,  compensation and recoveries for any
damage  to or  condemnation  or  taking  of the  Improvements  or  the  Personal
Property,   or  for  any   conveyance  in  lieu  thereof,   whether   direct  or
consequential,  or for any damage or injury to the  Improvements or the Personal
Property,  or for any loss or  diminution  in value of the  Improvements  or the
Personal Property;

         (j) All architectural, structural, mechanical and engineering plans and
specifications  prepared for construction of Improvements and all studies,  data
and drawings  related  thereto,  and all  contracts  and  agreements of Borrower
relating to such plans and  specification or such studies,  data and drawings or
to the construction of Improvements;

         (k) All of Borrower's  present and future rights in and to all refunds,
rebates,  reimbursements,  reserves, deferred payments,  deposits, cost savings,
governmental   subsidy  payments,   governmental-registered   credits  (such  as
emissions reduction credits),  other credits,  waivers and payments,  whether in
cash or kind, due from or payable by any Governmental Agency or any insurance or
utility  company  relating to any or all of the  Improvements  or arising out of
satisfaction of any condition imposed upon or the obtaining of any approvals for
the development of the Improvements;

         (l) All of Borrower's  present and future rights in and to all refunds,
rebates, reimbursements, credits and payments of any kind due from or payable by
any  Governmental  Agency  or  other  entity  for  any  taxes,   special  taxes,
assessments,  or similar  governmental or  quasi-governmental  charges or levies
imposed upon  Borrower  with respect to the  Improvements  or arising out of the
satisfaction of any condition imposed upon or the obtaining of any approvals for
the development of the Improvements;

         (m)      All Borrower's rights in proceeds of the Loan;

         (n) All Borrower's  rights to receive the proceeds of any "take-out" or
permanent financing or commitment to provide such financing; and

         All terms used herein  which are defined in the  California  Commercial
Code shall have the same meanings when used herein,  unless the context requires
otherwise.

                                      C-2

<PAGE>


                                   EXHIBIT D

                            Form of Promissory Note

                            SECURED PROMISSORY NOTE

$6,000,000.00                                              San Diego, California
                                                           as of March __, 1998

         FOR VALUE RECEIVED, MATRIX PHARMACEUTICAL, INC., a Delaware corporation
(the "Maker"),  promises to pay, on or before the "Due Date" (as defined below),
to the order of ARE4-757 NEXUS CENTRE, LLC, a Delaware limited liability company
or its designee (the "Holder"),  having an address at c/o Alexandria Real Estate
Equities, Inc., 135 N. Los Robles Avenue, Suite 250, Pasadena, California 91101,
at said address or in accordance  with such other  instructions  or place as the
Holder may hereafter  designate from time to time in writing,  the principal sum
of SIX MILLION  DOLLARS  ($6,000,000.00)  in lawful money of the United  States,
with  interest on the  "Principal  Balance" (as defined  below) from the date of
this Secured  Promissory  Note (this  "Note") to and including the date on which
this Note is paid in full, calculated in the manner hereinafter set forth.

         1.  As used  herein,  the  term  "Principal  Balance"  shall  mean  the
outstanding principal balance of this Note from time to time.

         2. The entire  Principal  Balance  shall bear  interest  at the rate of
eleven percent (11%) per annum,  calculated on the basis of the actual number of
days elapsed over a 365 day year.  Interest only on the Principal  Balance shall
be payable monthly, in arrears, commencing on the last day of the month in which
this Note is executed  and  thereafter  on the last  business  day of each month
until paid in full.  All  accrued  and  unpaid  interest,  and any other  unpaid
charges accruing or due hereunder,  shall be added to the Principal Balance on a
monthly basis.



<PAGE>


         3. The entire unpaid Principal  Balance,  together with all accrued and
unpaid interest thereon,  shall be due and payable on the date which is four (4)
calendar years from the date of this Note (the "Due Date").

         4. This Note is subject to the express  condition that at no time shall
the Maker be  obligated  or required to pay  interest on any amount  outstanding
hereunder  at a rate which could  subject the Holder to either civil or criminal
liability as a result of such rate being in excess of the maximum rate which the
Maker is  permitted  by law to contract or agree to pay. If by the terms of this
Note the Maker is at any time  required  or  obligated  to pay  interest  on any
amount outstanding  hereunder at a rate in excess of such maximum rate, the rate
of interest  under this Note shall be deemed to be  immediately  reduced to such
maximum rate and interest  payable  hereunder  shall be computed at such maximum
rate and the portion of all prior  interest  payments in excess of such  maximum
rate shall be applied and shall be deemed to have been  payments in reduction of
the principal amount outstanding hereunder.

         5. The Maker hereby waives  presentment and demand for payment,  notice
of dishonor,  protest and notice of protest of this Note,  and agrees to pay all
costs of  collection  when  incurred,  including  attorneys'  fees,  charges and
disbursements  (which  amounts  shall  be added to the  Principal  Balance).  No
extension of time for payment of this Note or any installment hereunder,  and no
alteration,  amendment or waiver of any provision of this Note,  shall  release,
discharge, modify, change or affect the liability of the Maker hereunder.

         6. Maker may make full or partial  prepayment of the Principal  Balance
together  with accrued and unpaid  interest  thereon at any time or from time to
time without  penalty or charge,  upon at least 30 days' prior written notice to
Holder.

         7. All payments  received  hereunder  shall be applied first to accrued
interest,  then to any due and unpaid  charges  incurred by Holder in connection
with this Note and thereafter to a reduction of the Principal Balance.

         8. In the event of any  default by Maker  under the terms of this Note,
time being of the  essence,  Holder may,  in  addition  to any other  rights and
remedies which Holder may have  hereunder,  at law, in equity,  pursuant to: (a)
that certain Loan and  Security  Agreement of even date  herewith by and between
Maker and Holder (the "Loan Agreement"); (b) that certain Lease of even date

                                       2

<PAGE>


herewith by and between Holder, as landlord, and Maker, as tenant (the "Lease");
(c) that certain Deed of Trust and Fixture Filing of even date herewith executed
by Maker, as trustor, to Chicago Title Insurance Company, as trustee, and naming
Holder,  as  beneficiary,  to be recorded  concurrently  herewith  (the "Deed of
Trust");  and (d) that certain California UCC-1 Financing Statement of even date
herewith to be filed with the California Secretary of State, together with UCC-1
Financing   Statements   for  such  other  States  as  are  required  by  Holder
(collectively,  the "Financing  Statement") (the Loan Agreement,  the Lease, the
Deed of Trust and the Financing Statement are herein collectively referred to as
the "Loan Documents"), or otherwise, at any time following such default, without
waiving  any other  rights or  remedies  available  to it,  declare  the  entire
Principal  Balance,  accrued  interest and all other amounts  payable under this
Note,  immediately due and payable,  and the entire sum shall thereby become due
and payable.

         9. If any action is brought in connection with or to enforce this Note,
or if this Note is placed in the hands of an attorney  or agent for  collection,
Maker shall pay all costs,  fees and disbursements of such action or collection,
including,   without  limitation,   reasonable   attorneys'  fees,  charges  and
disbursements,  and all such  sums  shall be  added  to and  become  part of the
Principal Balance as and when incurred.

         10. This Note is the promissory  note referred to in the Loan Agreement
and is secured by the Deed of Trust.

         11. This Note and Maker's  obligations  hereunder and under each of the
other Loan Documents are intended to be, and shall be,  recourse  obligations of
Maker,  and Holder  shall have full  recourse  to Maker and all of its assets in
connection with any default hereunder or under any of the other Loan Documents.

         12. The terms of this Note shall be governed by and construed under the
laws of the State of California.

         13. This Note may not be amended or terminated  orally,  but only by an
agreement in writing executed by the Holder.

                                       3

<PAGE>


         IN WITNESS  WHEREOF,  the Maker has duly  executed  this Note as of the
date first above written.

                                                    MAKER:

                                                    MATRIX PHARMACEUTICAL, INC.,
                                                    a Delaware corporation

                                                    By: ________________________
                                                       Name: ___________________
                                                       Its: ____________________

                                       4

<PAGE>


                                  EXHIBIT "E"
                                Permitted Liens

                            EXCEPTIONS FROM COVERAGE

     This policy does not insure  against  loss or damage (and the Company  will
not pay costs, attorneys' fees or expenses) which arise by reason of:

A    1. PROPERTY TAXES,  INCLUDING ANY  ASSESSMENTS  COLLECTED WITH TAXES, TO BE
        LEVIED FOR THE FISCAL YEAR 1998-99 THAT ARE A LIEN NOT YET DUE.

B    2. THE  LIEN OF  SUPPLEMENTAL  TAXES,  IF  ANY,  ASSESSED  PURSUANT  TO THE
        PROVISIONS  OF CHAPTER 3.5  (COMMENCING  WITH SECTION 75) OF THE REVENUE
        AND TAXATION CODE OF THE STATE OF CALIFORNIA.

C    3. THE FACT THAT THE  OWNERSHIP  OF SAID LAND  DOES NOT  INCLUDE  RIGHTS OF
        ACCESS TO OR FROM THE STREET OR HIGHWAY  ABUTTING SAID LAND, SUCH RIGHTS
        HAVING BEEN SEVERED FROM SAID LAND BY THE DOCUMENT.

        RECORDED: APRIL 8, 1969 AS FILE NO. 59708, OFFICIAL RECORDS

        AFFECTS:  IN AND TO  I-805  FREEWAY,  BEING A  PORTION  OF THE  EASTERLY
                  BOUNDARY OF PARCEL 2 AS SHOWN ON PARCEL MAP 17892.

D    4. THE RIGHTS,  AS A  "RESTRICTIVE  USE EASEMENT" AS RESERVED BY THE UNITED
        STATES OF AMERICA IN DEED DATED JULY 21, 1983 AND RECORDED JULY 28, 1983
        AS FILE NO. 83-261437.

        REFERENCE IS MADE TO SAID DOCUMENT FOR FULL PARTICULARS.

        THE EXACT  LOCATION  AND EXTENT OF SAID  EASEMENT  IS NOT  DISCLOSED  OF
        RECORD.

E    5. A  RESTRICTIVE  USE  EASEMENT  IN  PERPETUITY  FOR  THE   ESTABLISHMENT,
        MAINTENANCE,  OPERATION AND USE OF A SAFETY AREA OF COMPATIBLE  USE ZONE
        IN CONNECTION WITH THE OPERATION OF THE NAVAL AIR  STATION  MIRAMAR  AND
        INCIDENTAL PURPOSES, IN FAVOR OF UNITED STATES OF AMERICA, RECORDED JULY
        JULY 28, 1983 AS FILE NO. 83-261438 OF OFFICIAL RECORDS.

        REFERENCE IS MADE TO SAID DOCUMENT FOR FULL PARTICULARS.

        THE EXACT  LOCATION  AND EXTENT OF SAID  EASEMENT  IS NOT  DISCLOSED  OF
        RECORD.

F    6. COVENANTS,  CONDITIONS  AND  RESTRICTIONS  (BUT OMITTING ANY COVENANT OR
        RESTRICTIONS BASED ON RACE, COLOR,  RELIGION,  SEX,  HANDICAP,  FAMILIAL
        STATUS, OR NATIONAL ORIGIN) AS SET FORTH IN THE DOCUMENT.

        RECORDED: JULY 28, 1983 AS FILE NO. 83-261430, OFFICIAL RECORDS

G    7. PLANNING  DIRECTOR  RESOLUTION NO. 7493 PD GRANTING  PLANNED  INDUSTRIAL
        DEVELOPMENT PERMIT NO. 87-1049 AMENDMENT TO PID PERMIT NO. 86-0967.

<PAGE>

        RECORDED JUNE 14, 1988 AS FILE NO. 88-283002.

H    8. AN OFFER OF  DEDICATION  TO PUBLIC USE OF, A PORTION OF SAID LAND,  SAID
        OFFER WAS  REJECTED  ON SAID MAP,  BUT IS SUBJECT  TO FUTURE  ACCEPTANCE
        UNDER THE PROVISIONS OF SECTION NUMBER 66477.2 OF THE GOVERNMENT CODE OF
        THE STATE OF CALIFORNIA.

        DESIGNATED ON
        MAP NO.:            12473
        AS:                 RESERVED FOR FUTURE STREET
        AFFECTS:            A PORTION OF PARCEL 2 AS SHOWN ON PARCEL MAP 17892

I    9. AN EASEMENT FOR THE PURPOSE SHOWN BELOW AND RIGHTS INCIDENTAL THERETO AS
        SHOWN ON MAP OF SAID TRACT.

        EASEMENT
        PURPOSE:            SEWER, DRAINAGE, SLOPE
        AFFECTS:            AS SHOWN ON SAID MAP NO. 12473
        
        NOTE: A PORTION OF SAID EASEMENT WAS ABANDONED ON PARCEL MAP 17892.

J   10. AN EASEMENT FOR THE PURPOSE SHOWN BELOW AND RIGHTS INCIDENTAL THERETO AS
        SET FORTH IN A DOCUMENT

        GRANTED TO:         SAN DIEGO GAS & ELECTRIC COMPANY
        PURPOSE:            PUBLIC UTILITIES, INGRESS AND EGRESS
        RECORDED:           DECEMBER 27, 1989 AS FILE NO. 89-699805, OFFICIAL 
                            RECORDS
        AFFECTS:            THE EXACT LOCATION AND EXTENT OF SAID EASEMENT IS 
                            NOT DISCLOSED OF RECORD.

K       RESTRICTIONS  ON THE USE,  BY THE OWNERS OF SAID LAND,  OF THE  EASEMENT
        AREA AS PROVIDED IN THE DOCUMENT REFERRED TO ABOVE.

N   11.  AN AGREEMENT  BETWEEN THE CITY OF SAN DIEGO AND NEXUS  CENTRE/I-805,  A
         CALIFORNIA LIMITED  PARTNERSHIP,  OWNER,  RECORDED FEBRUARY 20, 1992 AS
         FILE NO.  92-0091575,  OFFICIAL RECORDS,  RELATING TO THE INSTALLATION,
         MAINTENANCE  AND POSSIBLE  REMOVAL OF 6" PRIVATE  SEWER LATERAL AND 12"
         PRIVATE DRAINAGE PIPE.

N    12. PROVISIONS, HEREIN RECITED, OF THE DEDICATION STATEMENT ON THE

MAP NO:                     PARCEL MAP 16892 AND 17892
PROVISIONS:                 THIS IS A MAP OF A PLANNED INDUSTRIAL DEVELOPMENT
                            PROJECT AS DEFINED IN CHAPTER X, ARTICLE I, DIVISION
                            9 OF THE SAN DIEGO MUNICIPAL CODE.

                             Exhibit "E" (Continued)
<PAGE>

O    13. A PENDING  ASSESSMENT FOR THE DISTRICT SHOWN BELOW.  WHEN NOTICE OF THE
         ASSESSMENT IS  RECORDED WITH THE COUNTY  RECORDER THE ASSESSMENT  SHALL
         BECOME A LIEN ON SAID LAND.

     DISTRICT:  DISTRICT  DIAGRAM  OF NORTH  UNIVERSITY  CITY  AMENDED  DISTRICT
                DIAGRAM  FACILITIES BENEFIT ASSESSMENT IN THE CITY OF SAN DIEGO,
                COUNTY OF SAN DIEGO, STATE OF CALIFORNIA
        
        DISCLOSED BY:       ASSESSMENT DISTRICT DIAGRAM AMENDED
        RECORDED:           AUGUST 9, 1994 AS FILE NO. 1994-0485272, OFFICIAL
                            RECORDS
        
P        NOTICE OF ASSESSMENT  RECORDED OCTOBER 1, 1991 AS FILE NO.  1991-506423
         AS AUGUST 9, 1994 AS FILE NO. 1994-0485273, OFFICIAL RECORDS

Q    14. AN EASEMENT FOR THE PURPOSE SHOWN BELOW AND RIGHTS  INCIDENTAL  THERETO
         AS SET FORTH IN A DOCUMENT

        GRANTED TO:         CITY OF SAN DIEGO
        PURPOSE:            TUNNEL OR TUNNELS FOR UTILITY PURPOSES
        RECORDED:           MARCH  3,  1995 AS FILE NO.  1995-0093861,  OFFICIAL
                            RECORDS
        AFFECTS:            THE ROUTE THEREOF AFFECTS A PORTION OF SAID LAND AND
                            IS MORE FULLY DESCRIBED IN SAID DOCUMENT.

R    15. AN AGREEMENT  BETWEEN THE CITY OF SAN DIEGO AND MATRIX  PHARMACEUTICAL,
         INC., A DELAWARE  CORPORATION,  OWNER,  RECORDED APRIL 24, 1997 AS FILE
         NO.  1997-0189196 OF OFFICIAL  RECORDS.  RELATING TO THE  INSTALLATION,
         MAINTENANCE  AND POSSIBLE  REMOVAL OF TRASH  ENCLOSURE,  WATER SERVICE,
         PAVEMENT AND LANDSCAPING.

S    16. ANY RIGHTS,  INTEREST,  OR CLAIMS WHICH MAY EXIST OR ARISE BY REASON OF
         THE FOLLOWING FACTS.

        A) IMPROVEMENTS  LIE WITHIN THE  RESTRICTIVE USE EASEMENT  RECORDED JULY
        21, 1983 AS FILE NO. 83-261437.

        B) A BUILDING,  CURBS, DECORATIVE CONCRETE, WALLS & STAIRS ENCROACH ONTO
        THE EASEMENT FOR WATER, SEWER, DRAINAGE AND SLOPE SHOWN ON MAP 12473.

T       17. AN  EASEMENT  FOR THE  PURPOSE  SHOWN  BELOW AND  RIGHTS  INCIDENTAL
        THERETO AS SHOWN OR AS OFFERED FOR  DEDICATION ON THE RECORDED MAP SHOWN
        BELOW.

        MAP NO:             PARCEL MAP 17892 EASEMENT
        PURPOSE:            24' WIDE WATER EASEMENT
        AFFECTS:            AS SHOWN ON SAID MAP

                             Exhibit "E" (Continued)

<PAGE>

AB   19. AN UNRECORDED LEASE AFFECTING THE PREMISES HEREIN  DESCRIBED,  EXECUTED
         BY AND BETWEEN THE PARTIES HEREIN NAMED, WITH CERTAIN TERMS, COVENANTS,
         CONDITIONS AND PROVISIONS SET FORTH THEREIN.

        LESSOR:        ARE-4757 NEXUS CENTRE, LLC
        LESSEE:        MATRIX PHARMACEUTICAL, INC.
        DISCLOSED BY:  MEMORANDOM OF LEASE (PARKING LEASE)
        RECORDED:      ----

AC   21. A   DOCUMENT   ENTITLED   "DECLARATION   OF   RECIPROCAL    EASEMENTS,"
         DATED-EXECUTED  BY  MATRIX  PHARMACEUTICAL,  INC.,  SUBJECT  TO ALL THE
         TERMS, PROVISIONS AND CONDITIONS THEREIN CONTAINED, RECORDED-.


                            Exhibit "E" (Continued)