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                                                                   Exhibit 10.9

                                LEASE AGREEMENT
                                     (Net)
                            BASIC LEASE INFORMATION

Lease Date:         September 13, 1996

Lessor:             Aetna Life Insurance Company,
                    a Connecticut Corporation

Lessor's Address:   P.O. Box 19693, 30 Executive Park, Suite 100
                    Irvine, California 92713-9693

Lessee:             Advanced Corneal Systems, Inc.,
                    a California Corporation

Lessee's Address:   23046 Avenida de la Carlota, Suite 600
                    Laguna Hills, CA 92653

Premises:           Approximately 12,946 square feet as shown on Exhibit A

Premises Address:   15279 Alton Parkway, Suite 100
                    Irvine, CA 92618

                    Park: 213,585 square feet

Term:               October 1, 1996 ("Commencement Date"), through
                    September 30, 2001 ("Expiration Date")

Base Rent           Ten Thousand Six Hundred Sixteen Dollars and No Cents
 (Paragraph 3):     ($10,616.00) per month

Adjustments to      November 1, 1996 - December 31, 1996  $   -0-    per month
  Base Rent:        January 1, 1997 - September 30, 1997  $10,616.00 per month
                    October 1, 1997 - September 30, 1998  $11,041.00 per month
                    October 1, 1998 - September 30, 1999  $11,483.00 per month
                    October 1, 1999 - September 30, 2000  $11,942.00 per month
                    October 1, 2000 - September 30, 2001  $12,420.00 per month

Security Deposit    Fifty Thousand Dollars and No Cents ($50,000.00). See
  (Paragraph 4.A):  Paragraph 39

Cleaning Deposit    N/A
  (Paragraph 4.B):

*Lessee's Share of
Operating Expenses  6.06% of the Park
  (Paragraph 6.A):

*Lessee's Share of
Tax Expenses        6.06% of the Park
  (Paragraph 6.B):

*Lessee's Share of
Common Area Utility
Costs               6.06% of the Park
  (Paragraph 7):

*The amount of Lessee's Share of the expenses as referenced above shall be
subject to modification as set forth in this Lease.

Permitted Uses:     General offices and research and development laboratory for
                    an ophthalmology company.


General Liability
Insurance Amount    Bodily injury limit of not less than $1,000,000.00 per
  (Paragraph 12):   occurrence;
                    Property damage limit of not less than $1,000,000.00
                    per occurrence;
                    Combined single limit of not less than $2,000,000.00.

Unreserved Parking
Spaces:             Forty-four (44) nonexclusive and undesignated spaces

Broker              Lee & Associates, 15615 Alton Parkway, Suite 150,
  (Paragraph 38):   Irvine, CA 92718

Exhibits:           Exhibit A - Premises, Building, Lot and/or Park
                    Exhibit B - Tenant Improvements
                    Exhibit C - Rules and Regulations
                    Exhibit D - Sign Criteria
                    Exhibit E - Hazardous Materials Disclosure Certificate
                    Exhibit F - Change of Commencement Date

Addenda:            Addendum I:

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                                  LEASE AGREEMENT

DATE:     This Lease is made and entered into as of the Lease Date defined on
          Page 1. The Basic Lease information set forth on Page 1 and this Lease
          are and shall be construed as a single instrument.

1.   PREMISES: Lessor hereby leases the Premises to Lessee upon the terms and
conditions contained herein. Lessor hereby grants to Lessee a revocable license
for the right to use, on a non-exclusive basis, parking areas and ancillary
facilities located within the Common Area of the Park, subject to the terms of
this Lease.

2.   ADJUSTMENT OF COMMENCEMENT DATE: CONDITION OF THE PREMISES:

     A.   If Lessor cannot deliver possession of the Premises on the
Commencement Date, Lessor shall not be subject to any liability nor shall the
validity of the Lease be affected; provided the Lease term and the obligation
to pay Rent shall commence on the date possession is tendered and the
termination date shall be extended by a period of time equal to the period
computed from the Commencement Date to the date possession is tendered by
Lessor to Lessee. In the event the commencement date of this Lease is other
than the Commencement Date provided on Page 1, Lessor and Lessee shall execute
a written amendment to this Lease, substantially in the form of Exhibit F
hereto, wherein the parties shall specify the actual commencement date,
termination date and the date on which Lessee is to commence paying Rent. In
the event that Lessor permits Lessee to occupy the Premises prior to the
Commencement Date, such occupancy shall be at Lessee's sole risk and subject to
all the provisions of this Lease, including, but not limited to, the
requirement to pay Rent and the Security Deposit, and to obtain the insurance
required pursuant to this Lease and to deliver insurance certificates as
required herein. In addition to the foregoing, Lessor shall have the right to
impose such additional conditions on Lessee's early entry as Lessor shall deem
appropriate. By taking possession of the Premises, Lessee shall be deemed to
have accepted the Premises in a good, clean and completed condition and state
of repair, in compliance with applicable laws, codes, regulations,
administrative orders and ordinances, and subject to all matters of record.
Lessee hereby acknowledges and agrees that neither Lessor nor Lessor's agents
or representatives has made any representations or warranties as to the
suitability, safety or fitness of the Premises for the conduct of Lessee's
business, Lessee's intended use of the Premises or for any other purpose, and
that neither Lessor nor Lessor's agents or representatives has agreed to
undertake any alterations or construct any Tenant Improvements to the Premises
except as expressly provided in this Lease.

     B.   Notwithstanding anything to the contrary in Paragraph 2.A above, in
the event Lessor fails to deliver possession of the Premises to Lessee on or
before April 1, 1997, then Lessee shall have the right as its sole remedy for
such failure to terminate this Lease upon ten (10) days' notice to Lessor,
which notice shall be given, if at all, on or before April 10, 1997.

3.   RENT. On the date that Lessee executes this Lease, Lessee shall deliver to
Lessor the original executed Lease, the Base Rent (which shall be applied
against the Rent payable for the first month Lessee is required to pay Base
Rent), the Security Deposit, the Cleaning Deposit, and all insurance
certificates evidencing the insurance required to be obtained by Lessee under
Paragraph 12 of this Lease. Lessee agrees to pay Lessor, without prior notice or
demand, or abatement, offset, deduction or claim, the Base Rent described on
Page 1, payable in advance at Lessor's address shown on Page 1 on the first day
of each month throughout the term of the Lease. In addition to the Base Rent set
forth on Page 1, Lessee shall pay Lessor in advance and on the first (1st) day
of each month throughout the term of this Lease, (including any extensions of
such term), as additional rent Lessee's share, as set forth on Page 1, of
Operating Expenses, Tax Expenses, Common Area Utility Costs, administrative
expenses and Utility Expenses, as specified in Paragraphs 6.A., 6.B., 6.C. and 7
of this Lease, respectively. Additionally, Lessee shall pay to Lessor as
additional rent hereunder, immediately on Lessor's demand therefor, any and all
costs and expenses incurred by Lessor to enforce the provisions of this Lease,
including, but not limited to, costs associated with any proposed assignment or
subletting of all or any portion of the Premises by Lessee, costs associated
with the delivery of notices, delivery and recordation of notice(s) of default,
attorneys' fees, expert fees, court costs and filing fees (collectively, the
"Enforcement Expenses"). The term "Rent" whenever used herein refers to the
aggregate of all these amounts. If Lessor permits Lessee to occupy the Premises
without requiring Lessee to pay rental payments for a period of time, the waiver
of the requirement to pay rental payments shall only apply to waiver of the Base
Rent and Lessee shall otherwise perform all other obligations of Lessee
hereunder, including, but not limited to paying to Lessor any and all amounts
considered additional rent, such as Lessee's share of Operating Expenses, Tax
Expenses, Common Area Utility Costs, Utility Expenses, and administrative
expenses. If, at any time, Lessee is in default of or otherwise breaches any
term, condition or provision of this Lease, any such waiver by Lessor of
Lessee's requirement to pay rental payments shall be null and void and Lessee
shall immediately pay to Lessor all rental payments waived by Lessor. The Rent
for any fractional part of a calender month at the


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commencement or termination of the Lease term shall be a prorated amount of the
Rent for a full calendar month based upon a thirty (30) day month. The prorated
Rent shall be paid on the Commencement Date and the first day of the calendar
month in which the date of termination occurs, as the case may be.

4.   SECURITY DEPOSIT AND CLEANING DEPOSIT:

     A.  Security Deposit: Upon Lessee's execution of this Lease, Lessee shall
deliver to Lessor, as a Security Deposit for the performance by Lessee of its
obligations under this Lease, the amount described on Page 1. If Lessee is in
default, Lessor may, but without obligation to do so, use the Security Deposit,
or any portion thereof, to cure the default or to compensate Lessor for all
damages sustained by Lessor resulting from Lessee's default, including, but not
limited to the Enforcement Expenses. Lessee shall, immediately on demand, pay
to Lessor a sum equal to the portion of the Security Deposit so applied or used
so as to replenish the amount of the Security Deposit held up to the
amount initially deposited with Lessor. At anytime after Lessee has defaulted
hereunder, Lessor may require an increase in the amount of the Security Deposit
required  hereunder for the then balance of the Lease term and Lessee shall,
immediately on demand, pay to Lessor additional sums in the amount of such
increase. As soon as practicable after the termination of this Lease, Lessor
shall return the Security Deposit to Lessee, less such amounts as are
reasonably necessary, as determined by Lessor, to remedy Lessee's default(s)
hereunder or to otherwise restore the Premises to a clean and safe condition,
reasonable wear and tear excepted. If the cost to restore the Premises exceeds
the amount of the Security Deposit, Lessee shall promptly deliver to Lessor any
and all of such excess sums as determined solely by Lessor. Lessor shall not be
required to keep the Security Deposit separate from other funds, and, unless
otherwise required by law, Lessee shall not be entitled to interest on the
Security Deposit. In no event or circumstance shall Lessee have the right to
any use of the Security Deposit and, specifically, Lessee may not use the
Security Deposit as a credit or to otherwise offset any payments required
hereunder, including, but not limited to, Rent or any portion thereof.

     B.  CLEANING DEPOSIT: Intentionally Omitted.

5.   CONDITION OF PREMISES:

     A.  Lessee hereby accepts the Premises in its current "as is" condition
unless otherwise specified in Exhibit B, attached hereto and incorporated
herein by this reference. If so specified in Exhibit B hereto, Lessor or
Lessee, as the case may be, shall install the improvements ("Tenant
Improvements") on the Premises as described and in accordance with the terms,
conditions, criteria and provisions set forth in Exhibit B, attached and
incorporated herein by this reference. Lessee acknowledges that neither Lessor
nor any of Lessor's agents, representatives or employees has made any
representations as to the suitability or fitness of the Premises for the
conduct of Lessee's business or for any other purpose, and that neither Lessor
nor any of Lessor's agents, representatives or employees has agreed to undertake
any alterations or construct any Tenant Improvements to the Premises except as
expressly provided in Exhibit B to this Lease.

     B.  Notwithstanding anything to the contrary contained in Section 5.A
above, Lessor shall cause the HVAC, electrical and plumbing systems serving the
Premises to be in good working order and the roof on the Premises to be in good
condition on the Commencement Date. Lessee shall have a period of thirty (30)
days after the Commencement Date to provide Lessor with written notice of any
defects in the HVAC, electrical or plumbing systems or the roof. In the event
Lessee fails to notify Lessor of any such defects within the aforesaid period,
then Lessor shall be conclusively deemed to have satisfied its obligations
under this Paragraph 5.B.

6.   EXPENSES:

     A.  OPERATING EXPENSES: In addition to the Base Rent set forth in
Paragraph 3, Lessee shall pay its share, which is defined on Page 1, of all
Operating Expenses as additional rent. The term "Operating Expenses" as used
herein shall mean the total amounts paid or payable by Lessor in connection
with the ownership, maintenance, repair and operation of the Premises, the
Building and the Lot, and where applicable, of the Park referred to on Page 1.
The amount of Lessee's share of Operating Expenses shall be reviewed from time
to time by Lessor and shall be subject to modification by Lessor as reasonably
determined by Lessor. These Operating Expenses may include, but are not limited
to:
          (i)  Lessor's cost of non-structural repairs to and maintenance of
     the roof and exterior walls of the Building;

          (ii) Lessor's cost of maintaining the outside paved area, landscaping
     and other common areas for the Park. The term "Common Area" shall mean all
     areas and facilities within the Park exclusive of the Premises and the
     other portions of the Park leased exclusively to other tenants. The Common
     Area includes, but is not limited to, interior lobbies, mezzanines, parking
     areas, access and perimeter roads, sidewalks, landscaped areas and similar
     areas and facilities;



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     (iii)  Lessor's annual cost of insurance insuring against fire and
extended coverage (including, if Lessor elects, "all risk" coverage) and all
other insurance, including, but not limited to, earthquake, flood and/or
surface water endorsements for the Building, the Lot and the Park (including
the Common Area), and rental value insurance against loss of Rent in an amount
equal to the amount of Rent for a period of at least six (6) months commencing
on the date of loss;

     (iv)  Lessor's cost of modifications to the Building, the Common Area
and/or the Park occasioned by any rules, laws or regulations effective
subsequent to the commencement of the Lease;

     (v)  Lessor's cost of modifications to the Building, the Common Area
and/or the Park occasioned by any rules, laws or regulations arising from
Lessee's use of the Premises regardless of when such rules, laws or regulations
became effective;

     (vi)  If Lessor elects to so procure, Lessor's cost of preventative
maintenance, repair and replacement contracts including, but not limited to,
contracts for elevator systems and heating, ventilation and air conditioning
systems, and trash or refuse collection;

     (vii)  Lessor's cost of security and fire protection services for the
Park, if in Lessor's sole discretion such services are provided;

     (viii)  Lessor's establishment of reasonable reserves for replacements
and/or repairs of Common Area improvements, equipment and supplies;

     (ix)  Lessor's cost for the creation and negotiation of, and pursuant to,
any rail spur or track agreements, licenses, easements or other similar
undertakings; and

     (x)  Lessor's cost of supplies, equipment, rental equipment and other
similar items used in the operation and/or maintenance of the Park.

     Notwithstanding anything to the contrary contained in this Section 6.A,
the following items shall be specifically excluded from the definition of
"Operating Expenses":

     (1)  Costs occasioned by fire, acts of God or other casualties or by the
exercise of the power of eminent domain;

     (2)  Costs incurred by Lessor in remediating Hazardous Materials (as
hereinafter defined) from the Premises or the Property;

     (3)  Any excess costs, fines or penalties incurred because Lessor violated
any governmental rule or authority, provided, however, that for purposes of
this subparagraph (3), "excess costs" shall mean the excess costs resulting
from such violation and shall exclude the ordinary costs which would have been
incurred in complying with such governmental rule or authority absent such
violation; and

     (4)  Costs, including, without limitation, attorneys' fees, incurred by
Lessor in connection with negotiations or disputes with other tenants of the
Park.

     Nothing contained herein shall be deemed to restrict or limit the
obligations and liabilities of Lessee under Sections 13, 27, 28 or 29 below or
any other applicable provisions of this Lease.

     B.  TAX EXPENSES: In addition to the Base Rent set forth in Paragraph 3,
Lessee shall pay its share, which is defined on Page 1, of all real property
taxes applicable to the land and improvements included within the Lot on which
the Premises are situated and one hundred percent (100%) of all personal
property taxes now or hereafter assessed or levied against the Premises or
Lessee's personal property. The amount of Lessee's share of Tax Expenses shall
be reviewed from time to time by Lessor and shall be subject to modification by
Lessor as reasonably determined by Lessor. Lessee shall also pay any increase
in real property taxes attributable, in Lessor's reasonable discretion, to any
and all alterations, Tenant Improvements or other improvements of any kind
whatsoever placed in, on or about the Premises for the benefit of, at the
request of, or by Lessee. The term "Tax Expenses" includes, but is not limited
to, any form of tax and assessment (general, special, ordinary or
extraordinary), commercial rental tax, payments under any improvement bond or
bonds, license, rental tax, transaction tax, levy, or penalty imposed by
authority having the direct or indirect power of tax (including any city,
county, state or federal government, or any school, agricultural, lighting,
drainage or other improvement district thereof) as against any legal or
equitable interest of Lessor in the Premises, Lot or Park, as against Lessor's
right to rent or other income therefrom, or as against Lessor's business of
leasing the Premises or the occupancy of Lessee or any other

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tax, fee, or excise, however described (excluding inheritance or estate taxes),
including any value added tax, or any tax imposed in substitution, partially or
totally, of any tax previously included within the definition of real property
taxes, or any additional tax the nature of which was previously included within
the definition of real property tax.

     C.   PAYMENT OF EXPENSES AND ADMINISTRATIVE EXPENSES: Lessor shall
estimate the Operating Expenses and Tax Expenses which shall be paid by Lessee
for the calendar year in which the Lease commences. Commencing on the
Commencement Date, one-twelfth (1/12th) of this estimated amount shall be paid
by Lessee to Lessor, as additional rent, on the first (1st) day of each month
and throughout the remaining months of such calendar year. Thereafter, Lessor
may estimate such expenses as of the beginning of each calendar year and Lessee
shall pay one-twelfth (1/12th) of such estimated amount as additional rent
hereunder on the first day of each month during such calendar year and for each
ensuing calendar year throughout the term of this Lease (including any
extensions of the term). Not later than March 31 of each of the following
calendar years, or as soon thereafter as reasonably possible, including the
calendar year after the calendar year in which this Lease terminates or the
term expires, Lessor shall endeavor to furnish Lessee with a true and correct
accounting of actual Operating Expenses and Tax Expenses. Within thirty (30)
days of Lessor's delivery of such accounting, Lessee shall pay to Lessor the
amount of any underpayment. Notwithstanding the foregoing, failure by Lessor to
give such accounting by such date shall not constitute a waiver by Lessor of
its right to collect any of Lessee's underpayment at anytime. Lessor shall
credit the amount of any overpayment by Lessee toward the next estimated
monthly installment(s) falling due, or where the term of the Lease has expired,
refund the amount of overpayment to Lessee. Lessee, at its sole cost and
expense through any certified public accountant designated by it, shall have
the right to examine and/or audit the books and records evidencing such costs
and expenses for the previous one (1) calendar year, during Lessor's reasonable
business hours and not more frequently than once during any calendar year.
Lessee's obligations to pay its share of Operating Expenses and Tax Expenses
shall survive the expiration or earlier termination of this Lease.

     If the term of the Lease expires prior to the annual reconciliation of
expenses, if any, Lessor shall have the right to reasonably estimate Lessee's
share of such expenses, and if Lessor determines that an underpayment is due,
Lessee hereby agrees that Lessor shall be entitled to deduct such underpayment
from Lessee's Security Deposit. If Lessor reasonably determines that an
overpayment has been made by Lessee, Lessor shall refund said overpayment
together with the return of Lessee's Security Deposit. Notwithstanding the
foregoing, failure of Lessor to accurately estimate Lessee's share of such
expenses shall not constitute a waiver of Lessor's right to collect any of
Lessee's underpayment at anytime.

     In addition to the Base Rent set forth in Paragraph 3 hereof, Lessee shall
pay Lessor, without prior notice or demand, on the first (1st) day of each month
throughout the term of this Lease (including any extensions of such term), as
compensation to Lessor for accounting and management services rendered on behalf
of the Park, an amount equal to ten percent (10%) of the aggregate of Lessee's
share of (i) the total Operating Expenses and Tax Expenses as described in
Paragraphs 6.A. and 6.B. above, respectively, and (ii) all Common Area Utility
Costs for the Park as described in Paragraph 7. Lessee's obligations to pay its
share of such administrative expenses shall survive the expiration or earlier
termination of this Lease.

7.   UTILITIES:  Lessee shall pay the cost of all water, sewer use and
connection fees, gas, heat, electricity, refuse pickup, janitorial service,
telephone and other utilities billed or metered separately to the Premises
and/or Lessee. Lessee shall also pay its share of any assessments or charges
for utility or similar purposes included within any tax bill for the Lot on
which the Premises are situated. For any such utility fees or use charges that
are not billed or metered separately to Lessee, Lessee shall pay to Lessor, as
additional rent, without prior notice or demand, on the first (1st) day of each
month throughout the term of this Lease the amount which is attributable to
Lessee's use of the Premises as reasonably estimated and determined by Lessor
based upon factors such as size of the Premises and intensity of use of such
utilities by Lessee such that Lessee shall pay the portion of such charges
reasonably consistent with Lessee's use of such utilities ("Utility Expenses").
If Lessee disputes any such estimate or determination, then Lessee shall either
pay the estimated amount or cause the Premises to be separately metered at
Lessee's sole expense. In addition, Lessee shall pay Lessor its share, which is
described on Page 1, as additional rent, of any Common Area utility costs,
fees, charges or expenses ("Common Area Utility Costs") within fifteen (15)
days after receiving a bill from Lessor. The amount of Lessee's share of Common
Area Utility Costs shall be reviewed from time to time by Lessor and shall be
subject to modification by Lessor as reasonably determined by Lessor. Lessee
acknowledges that the Premises may become subject to the rationing of utility
services or restrictions on utility use as required by a public utility
company, governmental agency or other similar entity having jurisdiction
thereof. Notwithstanding any such rationing or restrictions on use of any such
utility services, Lessee acknowledges and agrees that its tenancy and occupancy
hereunder shall be subject to such rationing restrictions as may be imposed
upon Lessor, Lessee, the Premises, the Building or the Park, and Lessee shall
in no event be excused or relieved from any covenant or obligation to be kept
or performed by Lessee by reason of any such rationing or restrictions. Lessee
further agrees to pay and discharge, prior to delinquency, any amount, tax,
charge, surcharge, assessment or imposition levied,


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assessed or imposed upon the Premises, or Lessee's use and occupancy thereof, or
as a result directly or indirectly of any such rationing or restrictions.

8.   LATE CHARGES: Lessee acknowledges that late payment by Lessee to Lessor of
Base Rent, Lessee's share of Operating Expenses, Tax Expenses, Common Area
Utility Costs, Utility Expenses or other sums due hereunder, will cause Lessor
to incur costs not contemplated by this Lease, the exact amount of such costs
being extremely difficult and impracticable to fix. Such costs include, without
limitation, processing and accounting charges, and late charges that may be
imposed on Lessor by the terms of any note secured by any encumbrance against
the Premises, and late charges and penalties due to the late payment of real
property taxes on the Premises. Therefore, if any installment of Rent or any
other sum due from Lessee is not received by Lessor within five (5) days after
notice (the "Late Rent Notice") from Lessor of such delinquency, Lessee shall
promptly pay to Lessor all of the following, as applicable: (a) an additional
sum equal to five percent (5%) of such delinquent amount plus interest on such
delinquent amount at the rate equal to the prime rate plus three percent (3%)
for the time period such payments are delinquent as a late charge for every
month or portion thereof that such sums remain unpaid, (b) the amount of
seventy-five dollars ($75) for each three-day notice prepared for, or served on,
Lessee, and (c) the amount of fifty dollars ($50) relating to checks for which
there are not sufficient funds; provided, however, that Lessor shall only be
required to provide Lessee with one (1) Late Rent Notice during any twelve (12)
month period and, after the giving of such Late Rent Notice, the aforesaid
charges shall be due and payable by Lessee if any subsequent installment of Rent
or other sum during such twelve (12) month period is not received by Lessor
within five (5) days after the date such Rent or other sum is due. The parties
agree that this late charge and the other charges referenced above represent a
fair and reasonable estimate of the costs that Lessor will incur by reason of
late payment by Lessee. Acceptance of any late charge or other charges shall not
constitute a waiver by Lessor of Lessee's default with respect to the delinquent
amount, nor prevent Lessor from exercising any of the other rights and remedies
available to Lessor for any other breach of Lessee under this Lease. If a late
charge or other charge becomes payable for any three (3) installments of Rent
within any twelve (12) month period, then Lessor, at Lessor's sole option, can
either require the Rent be paid quarterly in advance, or be paid monthly in
advance by cashier's check or by electronic funds transfer.

9.   USE OF PREMISES: The Premises are to be used solely for the uses stated on
Page 1 and for no other uses or purposes without Lessor's prior written consent.
The use of the Premises by Lessee and its agents, invitees and employees shall
be subject to, and at all times in compliance with, (a) any and all applicable
laws, ordinances, statutes, orders and regulations as same exist from time to
time (collectively, the "Laws"), and (b) any and all declarations of covenants,
conditions and restrictions ("CC&Rs") and any supplement thereto which has been
or hereafter is recorded in any official or public records with respect to the
Premises, the Building, the Lot and/or the Park, or any portion thereof.

     Lessee shall not use the Premises or permit anything to be done in or about
the Premises nor keep or bring anything therein which will in any way conflict
with any of the requirements of the Board of Fire Underwriters or similar body
now or hereafter constituted or in any way increase the existing rate of or
affect any policy of fire or other insurance upon the Building or any of its
contents, or cause a cancellation of any insurance policy. Lessee shall not do
or permit anything to be done in or about the Premises which will in any way
obstruct or interfere with the rights of Lessor, other tenants or occupants of
the Building, other buildings in the Park, or other persons or businesses in the
Park, or injure or annoy other tenants or use or allow the Premises to be used
for any improper, immoral, unlawful or objectionable purpose, as determined by
Lessor, in its sole discretion, for the benefit, quiet enjoyment and use by
Lessor and all other tenants or occupants of the Building or other buildings in
the Park; nor shall Lessee cause, maintain or permit any private or public
nuisance in, on or about the Premises, Building, Park and/or the Common Area,
including, but not limited to, any offensive odors, fumes or vibrations. Lessee
shall not damage or deface or otherwise commit or suffer to be committed any
waste in, upon or about the Premises. Lessee shall not store, nor permit any
other person or entity to store, any property, equipment, materials, supplies,
personal property or any other items or goods outside of the Premises. Lessee
shall not permit any animals, including, but not limited to, any household pets,
to be brought or kept in or about the Premises. Lessee shall place no loads upon
the floors, walls, or ceilings in excess of the maximum designed load permitted
by the applicable Uniform Building Code or which may damage the Building or
outside Park; nor place any harmful liquids in the drainage systems; nor dump or
store waste materials, refuse or other such materials, or allow such to remain
outside the Building area, except in refuse dumpsters or in any enclosed trash
areas provided. Lessee shall honor the terms of all recorded CC&Rs relating to
the Premises, the Building, the Lot and/or the Park. Lessee shall honor the
rules and regulations set forth in Exhibit C, attached to and made a part of
this Lease, and any other reasonable rules and regulations of Lessor now or
hereafter enacted relating to parking and the operation of the Building and the
Park.  If Lessee fails to comply with such Laws, CC&Rs, rules and regulations or
the provisions of this Lease, Lessor shall have the right to collect from Lessee
a reasonable sum as a penalty, in addition to all rights and remedies of Lessor
hereunder including, but not limited to, the payment by Lessee to Lessor of all
Enforcement Expenses and Lessor's

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costs and expenses, if any, to cure any of such failures of Lessee, if Lessor,
at its sole option, elects to undertake such cure.

10. ALTERATIONS AND ADDITIONS:

     A.   Lessee shall not install any signs, fixtures, improvements, nor make
or permit any other alterations or additions to the Premises without the prior
written consent of Lessor, which consent shall not be unreasonably withheld;
provided, however, that Lessee shall have the right to make non-structural and
non-mechanical alterations costing not more than $1,500.00 on an individual
basis or for a series of related alterations (collectively, "Permitted
Alterations"). If any alteration or addition is expressly consented to by
Lessor, or if Lessee desires to make any Permitted Alterations, Lessee shall
deliver at least twenty (20) days prior notice to Lessor, from the date Lessee
intends to commence construction, sufficient to enable Lessor to post a Notice
of Non-Responsibility. In all events, Lessee shall obtain all permits or other
governmental approvals prior to commencing any of such work and deliver a copy
of same to Lessor. All alterations and additions shall be installed by a
licensed contractor approved by Lessor, at Lessee's sole expense in compliance
with all applicable Laws, CC&Rs, and Lessor's rules and regulations. Lessee
shall keep the Premises and the property on which the Premises are situated free
from any liens arising out of any work performed, materials furnished or
obligations incurred by or on behalf of Lessee. As a condition to Lessor's
consent to the installation of any fixtures or improvements, Lessor may require
Lessee to post and obtain a completion and indemnity bond for up to one hundred
twenty-five percent (125%) of the cost of the work. In the event Lessee requests
Lessor's consent to an alteration, Lessee shall have the right to request
Lessor's advice whether or not such proposed alteration shall be required to be
removed at the expiration or termination of this Lease. If Lessee fails to
obtain such advice in writing, then Lessor shall have the right, at the
expiration or termination of this Lease, to require Lessee to remove such
alteration (and to repair any damage caused by such removal) or to surrender
such alteration to Lessor with the Premises. Upon termination of this Lease,
Lessee shall remove all signs, fixtures, furniture and furnishings and, subject
to the immediately preceding sentence, if requested by Lessor, remove any
improvements made by Lessee and repair any damage caused by the installation or
removal of such signs, fixtures, furniture, furnishings and improvements and
leave the Premises in as good condition as they were in at the time of the
commencement of this Lease, excepting for reasonable wear and tear. Reasonable
wear and tear shall not include any damage or deterioration that would have been
prevented by proper maintenance by Lessee or Lessee otherwise performing all of
its obligations under this Lease. All additions, alterations or improvements,
including, but not limited to, heating, lighting, electrical, air conditioning,
fixed partitioning, drapery, wall covering and paneling, built-in cabinet work
and carpeting installations made by Lessee and not otherwise removed by Lessee
upon the expiration or sooner termination of this Lease in accordance with the
terms hereof, together with all property that has become an integral part of the
Premises, shall become the property of Lessor upon such expiration or
termination and shall not be deemed trade fixtures.

     B.   Notwithstanding anything to the contrary contained in Paragraph 10.A
above or any other provision of this Lease, Lessor may, by notice to Lessee
given not later than sixty (60) days prior to the Expiration Date (except in
the event of a termination of this Lease prior to the scheduled Expiration
Date, in which event no advance notice shall be required), require Lessee to
either surrender to Lessor with the Premises the laboratory space to be
constructed by Lessee in the Premises, as shown on Exhibit A-1 hereto (the
"Labs"), without compensation to Lessee, or to remove the Labs and to repair
any damage caused by such removal at Lessee's sole cost and expense. In the
event Lessor requires Lessee to surrender the Labs to Lessor with the Premises,
Lessee shall have the right to remove its laboratory equipment, benches and
cabinets, provided, however, that Lessee shall repair any damage to the
Premises caused by such removal; and, provided further, that in no event shall
Lessee have the right to remove any sinks (unless specifically required to do
so by Lessor).

11.  REPAIRS AND MAINTENANCE:

     A.   MAINTENANCE BY LESSEE.   Throughout the Term, Lessee shall, at its
sole expense, (1) keep and maintain in good order and condition the Premises,
and repair and replace every part thereof, including glass, windows, interior
doors, interior door frames and interior door closers, interior lighting
(including, without limitation, light bulbs and ballasts), Lessee's signage,
interior demising walls and partitions, equipment, interior painting and
interior walls and floors (excepting only those portions of the Building or the
Park to be maintained by Lessor, as provided in Paragraph 11.B below), (2)
furnish all expendables, including light bulbs, paper goods and soaps, used in
the Premises, and (3) keep and maintain in good order and condition, repair and
replace all of Lessee's security systems in or about or serving the Premises.
Lessee shall not do nor shall Lessee allow Lessee's Agents (as hereinafter
defined) to do anything to cause any damage, deterioration or unsightliness to
the Premises, the Building or the Project.

                                       7
<PAGE>   8
     B. MAINTENANCE BY LESSOR. Subject to the provisions of Paragraphs 11.A, 27
and 28, and further subject to Lessee's obligation under Paragraph 6 to
reimburse Lessor for Lessee's share of the cost and expense of the following
items, Lessor agrees to repair and maintain the following items: the roof
coverings (provided that Lessee installs no additional air conditioning or
other equipment on the roof that damages the roof coverings, in which event
Lessee shall pay all costs resulting from the presence of such additional
equipment); window frames, window casements, skylights, exterior doors,
exterior door frames and exterior door closers; the heating, ventilating, air
conditioning, plumbing, sewer, drainage, electrical, fire protection, life
safety and security systems and other mechanical, electrical and communications
systems and equipment serving the Premises, the Building and/or the Park or any
part thereof; the parking areas, pavement, landscaping, sprinkler systems,
sidewalks, driveways, curbs, and lighting systems in the Common Areas; and the
roll-up doors, ramps and dock equipment including without limitation, dock
bumpers, dock plates, dock seals, dock levelers and dock lights located in or
on the Premises. Subject to the provisions of Paragraphs 11.A, 27 and 28,
Lessor, at its own cost and expense, agrees to repair and maintain the
following items: the structural portions of the roof (specifically excluding
the roof coverings), the foundation, the footings, the floor slab, the load
bearing walls, and the exterior walls (excluding any glass therein) of the
Building. Notwithstanding anything in this Paragraph 11.B to the contrary,
Lessor shall have the right to either repair or to require Lessee to repair any
damage to any portion of the Premises, the Building and/or the Park caused by
or created due to any act, omission, negligence or willful misconduct of Lessee
or Lessee's Agents and to restore the Premises, the Building and/or the Park,
as applicable, to the condition existing prior to the occurrence of such
damage; provided, however, that in the event Lessor elects to perform such
repair and restoration work, Lessee shall reimburse Lessor upon demand for all
costs and expenses incurred by Lessor in connection therewith. Lessor's
obligation hereunder to repair and maintain is subject to the condition
precedent that Lessor shall have received written notice of the need for such
repairs and maintenance and a reasonable time to perform such repair and
maintenance. Lessee shall promptly report in writing to Lessor any defective
condition known to it which Lessor is required to repair, and failure to so
report such defects shall make Lessee responsible to Lessor for any liability
incurred by Lessor by reason of such condition.

     C. LESSEE'S WAIVER OF RIGHTS. Lessee hereby expressly waives all rights to
make repairs at the expense of Lessor or to terminate this Lease, as provided
for in California Civil Code Sections 1941 and 1942, and 1932(1), respectively,
and any similar or successor statute or law in effect or any amendment thereof
during the Term.

12. INSURANCE:

     A. COMMERCIAL GENERAL LIABILITY INSURANCE. Lessee shall, at Lessee's
expense, secure and keep in force a "broad form" commercial general liability
insurance and property damage policy covering the Premises, insuring Lessee,
and naming Lessor and its lenders as additional insureds, against any liability
arising out of the ownership, use, occupancy or maintenance of the Premises.
The minimum limit of coverage of such policy shall be in the amount of not less
than One Million Dollars ($1,000,000.00) for injury or death of one person in
any one accident or occurrence and in the amount of not less than Two Million
Dollars ($2,000,000.00) for injury or death of more than one person in any one
accident or occurrence, shall include an extended liability endorsement
providing contractual liability coverage (which shall include coverage for
Lessee's indemnification obligations in this Lease), and shall contain a
severability of interest clause or a cross liability endorsement. Such
insurance shall further insure Lessor and Lessee against liability for property
damage of at least One Million Dollars ($1,000,000.00). Lessor may from time to
time require reasonable increases in any such limits if Lessor believes that
additional coverage is necessary or prudent. The limit of any insurance shall
not limit the liability of Lessee hereunder. No policy maintained by Lessee
under this Paragraph 12.A shall contain a deductible greater than two thousand
five hundred dollars($2,500.00). No policy shall be cancelable or subject to
reduction of coverage without thirty (30) days prior written notice to Lessor,
and loss payable clauses shall be subject to Lessor's approval. Such policies
of insurance shall be issued as primary policies and not contributing with or
in excess of coverage that Lessor may carry, by an insurance company authorized
to do business in the State of California for the issuance of such type of
insurance coverage and rated A.XIII or better in Best's Key Rating Guide.

     B. PERSONAL PROPERTY INSURANCE. Lessee shall maintain in full force and
effect on all of its personal property, furniture, furnishings, trade or
business fixtures and equipment (collectively, "Lessee's Property") on the
Premises, a policy or policies of fire and extended coverage insurance with
standard coverage endorsement to the extent of the full replacement cost
thereof. No such policy shall contain a deductible greater than two thousand
five hundred dollars ($2,500.00). During the term of this Lease the proceeds
from any such policy or policies of insurance shall be used for the repair or
replacement of the fixtures and equipment so insured. Lessor shall have no
interest in the insurance upon Lessee's equipment and fixtures and will sign all
documents reasonably necessary in connection with the settlement of any claim or
loss by Lessee. Lessor will not carry insurance on Lessee's Property.

                                       8
<PAGE>   9
     C.   WORKER'S COMPENSATION INSURANCE; EMPLOYER'S LIABILITY INSURANCE.
Lessee shall, at Lessee's expense, maintain in full force and effect worker's
compensation insurance with not less than the minimum limits required by law,
and employer's liability insurance with a minimum limit of coverage of One
Million Dollars ($1,000,000).

     D.   EVIDENCE OF COVERAGE. Lessee shall deliver to Lessor certificates of
insurance and true and complete copies of any and all endorsements required
herein for all insurance required to be maintained by Lessee hereunder at the
time of execution of this Lease by Lessee. Lessee shall, at least ten (10) days
prior to expiration of each policy, furnish Lessor with certificates of renewal
or "binders" thereof. Each certificate shall expressly provide that such
policies shall not be cancelable or otherwise subject to modification except
after thirty (30) days prior written notice to Lessor and the other parties
named as additional insureds as required in this Lease (except for cancellation
for nonpayment of premium, in which event cancellation shall not take effect
until at least ten (10) days notice has been given to Lessor).

13.  LIMITATION OF LIABILITY AND INDEMNITY: Except for damage resulting from the
gross negligence or willful misconduct of Lessor or its authorized
representatives, Lessee agrees to protect, defend (with counsel acceptable to
Lessor) and hold Lessor and Lessor's lender(s), partners, employees,
representatives, legal representatives, successors and assigns (collectively,
the "Indemnitees") harmless and indemnify the Indemnitees from and against all
liabilities, damages, claims, losses, judgments, charges and expenses (including
reasonable attorney's fees, costs of court and expenses necessary in the
prosecution or defense of any litigation including the enforcement of this
provision) arising from or in any way related to, directly or indirectly,
Lessee's use of the Premises and/or the Park, or the conduct of Lessee's
business, or from any activity, work or thing done, permitted or suffered by
Lessee in or about the Premises, or in any way connected with the Premises or
with the improvements or personal property therein, including, but not limited
to, any liability for injury to person or property of Lessee, its agents or
employees or third party persons. Lessee agrees that the obligations of Lessee
herein shall survive the expiration or earlier termination of this Lease.

     Except for damage resulting from the gross negligence or willful
misconduct of Lessor or its authorized representatives, or by the failure of
Lessor to observe any of the terms and conditions of this Lease, if such
failure has persisted for an unreasonable period of time after written notice
of such failure, Lessor shall not be liable to Lessee or any person(s)
whomsoever who may at any time be using or occupying or visiting the Premises,
the Building or the Park (collectively, "Lessee Parties") for any loss,
liability, injury, death or damage to Lessee or the Lessee Parties or the
property of Lessee or the Lessee Parties, for any injury to or loss of Lessee
or the Lessee Parties' business or for any damage or injury to any person from
any cause whatsoever, including, but not limited to, any acts, errors or
omissions by or on behalf of any other tenants or occupants of the Building
and/or the Park. Lessee shall not, in any event or circumstance, be permitted
to offset or otherwise credit against any payments of Rent required herein for
matters for which Lessor may be liable hereunder. Lessor and its authorized
representatives shall not be liable for any interference with light or air, or
for any latent defect in the Premises or the Building.

14.  ASSIGNMENT AND SUBLEASING:

     A.   PROHIBITION: Lessee shall not assign, mortgage, hypothecate,
encumber, grant any license or concession, pledge or otherwise transfer this
Lease (collectively, "assignment"), in whole or in part, whether voluntarily or
involuntarily or by operation of law, nor sublet or permit occupancy by any
person other than Lessee of all or any portion of the Premises without first
obtaining the prior written consent of Lessor, which shall not be unreasonably
withheld. If Lessee seeks to sublet or assign all or any portion of the
Premises, Lessee shall deliver to Lessor at least thirty (30) days prior to the
proposed commencement of the sublease or assignment (the "Proposed Effective
Date") the following: (i) the name of the proposed assignee or sublessee; (ii)
such information as to such assignee's or sublessee's financial responsibility
and standing as Lessor may reasonably require; and (iii) a copy of the proposed
sublease or assignment agreement and all agreement collateral thereto, which
instrument shall include a provision whereby the assignee or sublessee assumes
all of Lessee's obligations hereunder and agrees to be bound by the terms
hereof. As additional rent hereunder, Lessee shall pay to Lessor a fee in the
amount of five hundred dollars ($500) plus Lessee shall reimburse Lessor for
actual legal or other expenses incurred by Lessor in connection with any
request by Lessee for Lessor's consent to assignment or subletting. In the
event the sublease (1) by itself or taken together with prior sublease(s)
covers or totals, as the case may be, more than fifty percent (50%) of the
rentable square feet of the Premises or (2) is for a term which by itself or
taken together with prior or other subleases is greater than fifty percent
(50%) of the period remaining in the term of this Lease as of the time of the
Proposed Effective Date, then Lessor shall have the right, to be exercised by
giving written notice to Lessee, to recapture the space described in the
sublease. If such recapture notice is given, it shall serve to terminate this
Lease with respect to the proposed sublease space, or, if the proposed sublease
space covers all the Premises, it shall serve to terminate the entire term of
this

                                       9
<PAGE>   10
Lease, in either case as of the Proposed Effective Date. However, no termination
of this Lease with respect to part or all of the Premises shall become effective
without the prior written consent, where necessary, of the holder of each deed
of trust encumbering the Premises or any part thereof. If this Lease is
terminated pursuant to the foregoing with respect to less than the entire
Premises, the Rent shall be adjusted on the basis of the proportion of square
feet retained by Lessee to the square feet originally demised and this Lease as
so amended shall continue thereafter in full force and effect. Each permitted
assignee or sublessee shall assume and be deemed to assume this Lease and shall
be and remain liable jointly and severally with Lessee for payment of Rent and
for the due performance of, and compliance with all the terms, covenants,
conditions and agreements herein contained on Lessee's part to be performed or
complied with, for the term of this Lease. No assignment or subletting shall
affect the continuing primary liability of Lessee (which following assignment,
shall be joint and several with the assignee), and Lessee shall not be released
from performing any of the terms, covenants and conditions of this Lease. For
purposes hereof, in the event Lessee is a corporation, partnership, joint
venture, trust or other entity other than a natural person, any change in the
direct or indirect ownership of Lessee (whether pursuant to one or more
transfers) which results in a change of more than fifty percent (50%) in the
direct or indirect ownership of Lessee shall be deemed to be an assignment
within the meaning of this Paragraph 14 and shall be subject to all the
provisions hereof. Any and all options, first rights of refusal, tenant
improvement allowances and other similar rights granted to Lessee in this Lease,
if any, shall not be assignable by Lessee unless expressly authorized in writing
by Lessor.

     B.   EXCESS SUBLEASE RENTAL OR ASSIGNMENT CONSIDERATION: In the event of
any sublease or assignment of all or any portion of the Premises where the rent
or other consideration actually paid under the sublease or assignment, after
deducting reasonable, market-based leasing commissions actually paid by Lessee
in connection with such sublease or assignment, either initially or over the
term of the sublease or assignment exceeds the Rent or pro rata portion of the
Rent, as the case may be, for such space reserved in the Lease, Lessee shall pay
the Lessor monthly, as additional rent, at the same time as the monthly
installments of Rent are payable hereunder, fifty percent (50%) of the excess of
each such payment of rent or other consideration (after deducting the aforesaid
leasing commissions) in excess of the Rent called for hereunder.

     C.   WAIVER: Notwithstanding any assignment or sublease, or any
indulgences, waivers or extensions of time granted by Lessor to any assignee or
sublessee, or failure by Lessor to take action against any assignee or
sublessee, Lessee waives notice of any default of any assignee or sublessee and
agrees that Lessor may, at its option, proceed against Lessee without having
taken action against or joined  such assignee or sublessee, except that Lessee
shall have the benefit of any indulgences, waivers and extensions of time
granted to any such assignee or sublessee.

15.  WAIVER OF SUBROGATION: Lessor and Lessee hereby mutually waive any claim
against the other during the Term for any injury to person or loss or damage to
any of their property located on or about the Premises or the Park that is
caused by or results from perils covered by insurance carried by the respective
parties or required to be carried by the respective parties under the terms of
this Lease, to the extent of the proceeds of such insurance actually received
with respect to such injury, loss or damage (or, with respect to insurance
required to be carried under this Lease but not actually carried, the proceeds
of such insurance which would have been received had the party required to carry
such insurance actually maintained such coverage), whether or not due to the
negligence of the other party or its agents. Because the foregoing waivers will
preclude the assignment of any claim by way of subrogation to an insurance
company or any other person, each party now agrees to immediately give to its
insurer written notice of the terms of these mutual waivers and shall have their
insurance policies endorsed to prevent the invalidation of the insurance
coverage because of these waivers. Nothing in this Paragraph shall relieve a
party of liability to the other for failure to carry insurance required by this
Lease.

16.  AD VALOREM TAXES: Prior to delinquency, Lessee shall pay all taxes and
assessments levied upon trade fixtures, alterations, additions, improvements,
inventories and personal property located and/or installed on or in the Premises
by, or on behalf of, Lessee; and if requested by Lessor, Lessee shall promptly
deliver to Lessor copies of receipts for payment of all such taxes and
assessments. To the extent any such taxes are not separately assessed or billed
to Lessee, Lessee shall pay the amount thereof as invoiced by Lessor.

17.  SUBORDINATION: Without the necessity of any additional document being
executed by Lessee for the purpose of effecting a subordination, and at the
election of Lessor or any bona fide mortgagee or deed of trust beneficiary with
a lien on all or any portion of the Premises or any ground lessor with respect
to the land of which the Premises are a part, this Lease shall be subject and
subordinate at all times to: (i) all ground leases or underlying leases which
may now exist or hereafter be executed affecting the Building or the land upon
which the Building is situated or both, and (ii) the lien of any mortgage or
deed of trust which


                                       10
<PAGE>   11
may now exist or hereafter be executed in any amount for which the Building, the
Lot, ground leases or underlying leases, or Lessor's interest or estate in any
of said items is specified as security. Notwithstanding the foregoing, Lessor or
any such ground lessor, mortgagee, or any beneficiary shall have the right to
subordinate or cause to be subordinated any such ground leases or underlying
leases or any such liens to this Lease. If any ground lease or underlying lease
terminates for any reason or any mortgage or deed of trust is foreclosed or a
conveyance in lieu of foreclosure is made for any reason, Lessee shall,
notwithstanding any subordination and upon the request of such successor to
Lessor, attorn to and become the Lessee of the successor in interest to Lessor,
provided such successor in interest will not disturb Lessee's use, occupancy or
quiet enjoyment of the Premises so long as Lessee is not in default of the terms
and provisions of this Lease. The successor in interest to Lessor following
foreclosure, sale or deed in lieu thereof shall not be (a) liable for any act or
omission of any prior lessor or with respect to events occurring prior to
acquisition of ownership, except that such successor in interest shall be
responsible for the performance of any unperformed repair or maintenance
obligations under this Lease; (b) subject to any offsets or defenses which
Lessee might have against any prior lessor; (c) bound by prepayment of more than
one (1) month's Rent; or (d) liable to Lessee for any Security Deposit not
actually received by such successor in interest. Lessee covenants and agrees to
execute (and acknowledge if required by Lessor, any lender or ground lessor) and
deliver, within five (5) days of a demand or request by Lessor and in the form
requested by Lessor, ground lessor, mortgagee or beneficiary, any additional
documents evidencing the priority or subordination of this Lease with respect to
any such ground leases or underlying leases or the lien of any such mortgage or
deed of trust. Lessee's failure to timely execute and deliver such additional
documents shall, at Lessor's option, constitute a material default hereunder. It
is further agreed that Lessee shall be liable to Lessor, and shall indemnify
Lessor from and against any loss, cost, damage or expense, incidental,
consequential, or otherwise, arising or accruing directly or indirectly, from
any failure of Lessee to execute or deliver to Lessor any such additional
documents. Lessee hereby irrevocably appoints Lessor as attorney-in-fact of
Lessee, which appointment is coupled with an interest, to execute, deliver and
record any such documents in the name and on behalf of Lessee.

18. RIGHT OF ENTRY: Lessee grants Lessor or its agents the right to enter the
Premises upon twenty-four (24) hours prior notice (except in the event of an
emergency, in which case no notice shall be required) for purposes of
inspection, exhibition, posting of notices, repair or alteration. Lessee's
representatives shall have the right to accompany Lessor on such inspections. At
Lessor's option, Lessor shall at all times have and retain a key with which to
unlock all the doors in, upon and about the Premises, excluding Lessee's vaults
and safes. It is further agreed that Lessor shall have the right to use any and
all means Lessor deems necessary to enter the Premises in an emergency. Lessor
shall also have the right to place "for rent" and/or "for sale" signs on the
outside of the Premises. Lessee hereby waives any claim from damages or for any
injury or inconvenience to or interference with Lessee's business, or any other
loss occasioned thereby except for any claim for any of the foregoing arising
out of the gross active negligent acts or willful misconduct of Lessor or its
authorized representatives.

19. ESTOPPEL CERTIFICATE: Lessee shall execute (and acknowledge if required by
any lender or ground lessor) and deliver to Lessor, within ten (10) days after
Lessor provides such to Lessee, a statement in writing certifying that this
Lease is unmodified and in full force and effect (or, if modified, stating the
nature of such modification), the date to which the Rent and other charges are
paid in advance, if any, acknowledging that there are not, to Lessee's
knowledge, any uncured defaults on the part of Lessor hereunder or specifying
such defaults as are claimed, and such other matters as Lessor may reasonably
require. Any such statement may be conclusively relied upon by Lessor and any
prospective purchaser or encumbrancer of the Premises. Lessee's failure to
deliver such statement within such time shall be conclusive upon the Lessee that
(a) this Lease is in full force and effect, without modification except as may
be represented by Lessor; (b) there are no uncured defaults in Lessor's
performance; and (c) not more than one month's Rent has been paid in advance,
except in those instances when Lessee pays Rent quarterly in advance pursuant to
Paragraph 8 hereof, then not more than three month's Rent has been paid in
advance. Failure by Lessee to so deliver such certified estoppel certificate
shall be a default of the provisions of this Lease. Lessee shall be liable to
Lessor, and shall indemnify Lessor from and against any loss, cost, damage or
expense, incidental, consequential, or otherwise, arising or accruing directly
or indirectly, from any failure of Lessee to execute or deliver to Lessor any
such certified estoppel certificate.

     Lessee hereby irrevocably appoints Lessor as attorney-in-fact of Lessee,
which appointment is coupled with an interest, to act in Lessee's name, place
and stead to execute and deliver such estoppel certificate on behalf of Lessee.

20. LESSEE'S DEFAULT: The occurrence of any one or more of the following events
shall, at Lessor's option, constitute a default and breach of this Lease by
Lessee:


                                       11


<PAGE>   12
          (i)       The abandonment of the Premises by Lessee for a period of
     ten (10) consecutive days;

          (ii)      The failure by Lessee to make any payment of Rent or any
     other payment required hereunder on the date said payment is due;

          (iii)     The failure in the performance of any of Lessee's
     covenants, agreements or obligations hereunder (except those failures
     specified as events of default in other Paragraphs of this Paragraph 20,
     which shall be governed by such other Paragraphs), which failure continues
     for fifteen (15) days after written notice thereof from Lessor to Lessee
     provided that, if Lessee has exercised reasonable diligence to cure such
     failure and such failure cannot be cured within such fifteen (15) day
     period despite reasonable diligence, Lessee shall not be in default under
     this subparagraph unless Lessee fails thereafter diligently and
     continuously to prosecute the cure to completion;

          (iv)      The making of a general assignment by Lessee for the
     benefit of creditors, the filing of a voluntary petition by Lessee or the
     filing of an involuntary petition by any of Lessee's creditors seeking the
     rehabilitation, liquidation, or reorganization of Lessee under any law
     relating to bankruptcy, insolvency or other relief of debtors and, in the
     case of an involuntary action, the failure to remove or discharge the same
     within sixty (60) days of such filing, the appointment of a receiver or
     other custodian to take possession of substantially all of Lessee's assets
     or this leasehold, Lessee's insolvency or inability to pay Lessee's debts
     or failure generally to pay Lessee's debts when due, any court entering a
     decree or order directing the winding up or liquidation of Lessee or of
     substantially all of Lessee's assets, Lessee taking any action toward the
     dissolution or winding up of Lessee's affairs, the cessation or suspension
     of Lessee's use of the Premises, or the attachment, execution or other
     judicial seizure of substantially all of Lessee's assets or this leasehold;

          (v)       Lessee's use or storage of Hazardous Materials on the
     Premises other than as permitted by the provisions of Paragraph 29 below;

          (vi)      The making of any material misrepresentation or omission by
     Lessee in any materials delivered by or on behalf of Lessee to Lessor
     pursuant to this Lease; or

          (vii)     Lessee's default or other breach of any covenant, condition
     or provision of any lease agreement between Lessee or an affiliated
     entity of Lessee, as the tenant, and Lessor or an affiliated entity of
     Lessor, as landlord, with regard to any and all leased premises other than
     the Premises as described herein.

21.  REMEDIES FOR LESSEE'S DEFAULT: In the event of Lessee's default or breach
of the Lease, Lessor may terminate Lessee's right to possession of the Premises
by any lawful means in which case upon delivery of written notice by Lessor this
Lease shall terminate on the date specified by Lessor in such notice and Lessee
shall immediately surrender possession of the Premises to Lessor. In addition,
the Lessor shall have the immediate right of re-entry whether or not this Lease
is terminated, and if this right of re-entry is exercised following abandonment
of the Premises by Lessee, Lessor may consider any personal property belonging
to Lessee and left on the Premises to also have been abandoned. No re-entry or
taking possession of the Premises by Lessor pursuant to this Paragraph 21 shall
be construed as an election to terminate this Lease unless a written notice of
such intention is given to Lessee. If Lessor relets the Premises or any portion
thereof, (i) Lessee shall be liable immediately to Lessor for all costs Lessor
incurs in reletting the Premises or any part thereof, including, without
limitation, broker's commissions, expenses of cleaning, redecorating, and
further improving the Premises and other similar costs, and (ii) the rent
received by Lessor from such reletting shall be applied to the payment of,
first, any indebtedness from Lessee to Lessor other than Base Rent, Operating
Expenses, Tax Expenses, Common Area Utility Costs, and Utility Expenses; second,
all costs including maintenance, incurred by Lessor in reletting; and, third,
Base Rent, Operating Expenses, Tax Expenses, Common Area Utility Costs, and
Utility Expenses due under this Lease. After deducting the payments referred to
above, any sum remaining from the rental Lessor receives from reletting shall be
held by Lessor and applied in payment of future Rent as Rent becomes due under
this Lease. In no event shall Lessee be entitled to any excess rent received by
Lessor. Reletting may be for a period shorter or longer than the remaining term
of this Lease. No act by Lessor other than giving written notice to Lessee shall
terminate this Lease. Acts of maintenance, efforts to relet the Premises or the
appointment of a receiver on Lessor's initiative to protect Lessor's interest
under this Lease shall not constitute a termination of Lessee's right to
possession. So long as this Lease is not terminated, Lessor shall have the right
to remedy any default of Lessee, to maintain or improve the Premises, to cause a
receiver to be appointed to administer the Premises and new or existing
subleases and to add to the Rent payable hereunder all of Lessor's reasonable
costs in so doing, with interest at the maximum rate permitted by law from the
date of such expenditure.

                                       12
<PAGE>   13
     If Lessee breaches this Lease and abandons the property before the end of
the term, or if Lessee's right to possession is terminated by Lessor because of
a breach or default of the Lease, then in either such case, Lessor may recover
from Lessee all damages suffered by Lessor as a result of Lessee's failure to
perform its obligations hereunder, including, but not limited to, the cost of
any tenant improvements, and all costs Lessor incurs in reletting the Premises
or any part thereof, including without limitation, brokerage or leasing
commissions, expenses of cleaning, redecorating, and further improving the
Premises and like costs, and the worth at the time of the award (computed in
accordance with paragraph (3) of Subdivision (a) of Section 1951.2 of the
California Civil Code) of the amount by which the Rent then unpaid hereunder for
the balance of the Lease term exceeds the amount of such loss of Rent for the
same period which Lessee proves could be reasonably avoided by Lessor and in
such case, Lessor prior to the award, may relet the Premises for the purpose of
mitigating damages suffered by Lessor because of Lessee's failure to perform its
obligations hereunder; provided, however, that even though Lessee has abandoned
the Premises following such breach, this Lease shall nevertheless continue in
full force and effect for as long as Lessor does not terminate Lessee's right of
possession, and until such termination, Lessor shall have the remedy described
in Section 1951.4 of the California Civil Code (Lessor may continue this Lease
in effect after Lessee's breach and abandonment and recover Rent as it becomes
due, if Lessee has the right to sublet or assign, subject only to reasonable
limitations) and may enforce all its rights and remedies under this Lease,
including the right to recover the Rent from Lessee as it becomes due hereunder.
The "worth at the time of the award" within the meaning of Subparagraphs (a)(1)
and (a)(2) of Section 1951.2 of the California Civil Code shall be computed by
allowing interest at the rate of ten percent (10%) per annum. Lessee waives
redemption or relief from forfeiture under California Code of Civil Procedure
Sections 1174 and 1179, or under any other present or future law, in the event
Lessee is evicted or Lessor takes possession of the Premises by reason of any
default of Lessee hereunder.

     The foregoing rights and remedies of Lessor are not exclusive; they are
cumulative in addition to any rights and remedies now or hereafter existing at
law, in equity by statute or otherwise, or to any equitable remedies Lessor may
have, and to any remedies Lessor may have under bankruptcy laws or laws
affecting creditor's rights generally. In addition to all remedies set forth
above, if Lessee defaults or otherwise breaches this Lease, any and all Base
Rent waived by Lessor under Paragraph 3 above shall be immediately due and
payable to Lessor and all options granted to Lessee hereunder shall
automatically terminate, unless otherwise expressly agreed to in writing by
Lessor.

     The waiver by Lessor of any default or breach of any provision of this
Lease shall not be deemed or construed a waiver of any other breach or default
by Lessee hereunder or of any subsequent breach or default of this Lease,
except for the default specified in the waiver.

22.  HOLDING OVER: If Lessee holds possession of the Premises after the
expiration of the term of this Lease with Lessor's consent, Lessee shall become
a tenant from month-to-month upon the terms and provisions of this Lease,
provided the monthly Base Rent during such hold over period shall be 150% of
the Base Rent due on the last month of the Lease term, payable in advance on or
before the first day of each month. Such month-to-month tenancy shall not
constitute a renewal or extension for any further term. All options, if any,
granted under the terms of this Lease shall be deemed automatically terminated
and be of no force or effect during said month-to-month tenancy. Lessee shall
continue in possession until such tenancy shall be terminated by either Lessor
or Lessee giving written notice of termination to the other party at least
thirty (30) days prior to the effective date of termination. This paragraph
shall not be construed as Lessor's permission for Lessee to hold over.
Acceptance of Base Rent by Lessor following expiration or termination of this
Lease shall not constitute a renewal of this Lease.

23.  LESSOR'S DEFAULT: Lessor shall not be deemed in breach or default of this
Lease unless Lessor fails within a reasonable time to perform an obligation
required to be performed by Lessor hereunder. For purposes of this provision, a
reasonable time shall in no event be more than thirty (30) days after receipt
by Lessor of written notice specifying the nature of the obligation Lessor has
not performed; provided, however, that if the nature of Lessor's obligation is
such that more than thirty (30) days, after receipt of written notice, is
reasonably necessary for its performance, then Lessor shall not be in breach or
default of this Lease if performance of such obligation is commenced within
such thirty (30) day period and thereafter diligently pursued to completion.

24.  PARKING: Lessee shall have a license to use the number of undersignated
and nonexclusive parking spaces set forth on Page 1. Lessor shall exercise
reasonable efforts to insure that such spaces are available to Lessee for its
use, but Lessor shall not be required to enforce Lessee's right to use the same.


                                       13
<PAGE>   14
25. SALE OF PREMISES: In the event of any sale of the Premises by Lessor,
Lessor shall be and is hereby entirely released from any and all of its
obligations to perform or further perform under this Lease and from all
liability hereunder as of the date of such sale, provided that the purchaser
at such sale has assumed and agreed in writing to carry out any and all
covenants and obligations of Lessor hereunder. Lessee agrees to attorn to such
new owner provided such new owner does not disturb Lessee's use, occupancy or
quiet enjoyment of the Premises so long as Lessee is not in default of any of
the provisions of this Lease.

26.  WAIVER: No delay or omission in the exercise of any right or remedy of
Lessor on any default by Lessee shall impair such a right or remedy or be
construed as a waiver.

     The subsequent acceptance of Rent by Lessor after breach by Lessee of any
covenant or term of this Lease shall not be deemed a waiver of such breach,
other than a waiver of timely payment for the particular Rent payment involved,
and shall not prevent Lessor from maintaining an unlawful detainer or other
action based on such breach.

     No payment by Lessee or receipt by Lessor of a lesser amount than the
monthly Rent and other sums due hereunder shall be deemed to be other than on
account of the earliest Rent or other sums due, nor shall any endorsement or
statement on any check or accompanying check or payment be deemed an accord and
satisfaction; and Lessor may accept such check or payment without prejudice to
Lessor's right to recover the balance of such Rent or other sum or pursue any
other remedy provided in this Lease.

27. CASUALTY DAMAGE:

     A. If the Premises or any part thereof shall be damaged by fire or other
casualty, Lessee shall give prompt written notice thereof to Lessor. In case the
Building shall be so damaged by fire or other casualty that substantial
alteration or reconstruction of the Building shall, in Lessor's sole opinion, be
required (whether or not the Premises shall have been damaged by such fire or
other casualty), Lessor may, at its option, terminate this Lease by notifying
Lessee in writing of such termination within sixty (60) days after the date of
such damage, in which event the Rent shall be abated as of the date of such
damage. If Lessor does not elect to terminate this Lease and provided insurance
proceeds and any contributions from Lessee, if necessary, are available to fully
repair the damage, Lessor shall within ninety (90) days after the date of such
damage commence to repair and restore the Building and shall proceed with
reasonable diligence to restore the Building (except that Lessor shall not be
responsible for delays outside its control) to substantially the same condition
in which it was immediately prior to the happening of the casualty; provided,
Lessor shall not be required to rebuild, repair, or replace any part of Lessee's
furniture, furnishings or fixtures and equipment removable by Lessee or any
improvements, alterations or additions installed by or for the benefit of Lessee
under the provisions of this Lease. Lessor shall not in any event be required to
spend for such work an amount in excess of the insurance proceeds and any
contributions from Lessee if necessary, actually received by Lessor as a result
of the fire or other casualty. Lessor shall not be liable for any inconvenience
or annoyance to Lessee, injury to the business of Lessee, loss of use of any
part of the Premises by the Lessee or loss of Lessee's personal property
resulting in any way from such damage or the repair thereof, except that,
subject to the provisions of the next sentence, Lessor shall allow Lessee a fair
diminution of Rent during the time and to the extent the Premises are unfit for
occupancy. If the Premises or any other portion of the Building be damaged by
fire or other casualty resulting from the fault or active or passive negligence
or omissions of Lessee or any of Lessee's agents, employees, or invitees, the
Rent shall not be diminished during the repair of such damage and Lessee shall
be liable to Lessor for the cost and expense of the repair and restoration of
the Building caused thereby to the extent such cost and expense is not covered
by insurance proceeds. In the event the holder of any indebtedness secured by
the Premises requires that the insurance proceeds be applied to such
indebtedness, then Lessor shall have the right to terminate this Lease by
delivering written notice of termination to Lessee within thirty (30) days after
the date of notice to Lessee of any such event, whereupon all rights and
obligations shall cease and terminate hereunder.

     B. Notwithstanding anything to the contrary contained in this Paragraph
27, if the premises are damaged by fire or other casualty and if the damage
thereto is such that the Premises may not be substantially repaired or restored
to its condition existing immediately prior to such damage or destruction
within one hundred eighty (180) days from the date of such destruction, Lessee
shall have the right to terminate this Lease by written notice to Lessor, which
notice shall be given, if at all, within fifteen (15) days after Lessor informs
Lessee of the expected duration of the period of repair or restoration. In the
event Lessee elects to terminate this Lease under this Paragraph 27.B, this
Lease shall be deemed to have terminated as of the date on which Lessee
surrenders possession of the Premises to Lessor, except that if the damage to
the Premises materially impairs Lessee's ability to continue is business
operations in the Premises and if Lessee ceases its operations in the Premises
as of the date of such damage, then this Lease shall be deemed to have
terminated as of the date such damage occurred.

                                       14

<PAGE>   15
     C. Except as otherwise provided in this Paragraph 27, Lessee hereby waives
the provisions of Sections 1932(2.), 1933(4.), 1941 and 1942 of the California
Civil Code.

28. CONDEMNATION: If twenty-five percent (25%) or more of the Premises is
condemned by eminent domain, inversely condemned or sold in lieu of condemnation
for any public or quasi-public use or purpose ("Condemned"), then Lessee or
Lessor may terminate this Lease as of the date when physical possession of the
Premises is taken and title vests in such condemning authority, and Rent shall
be adjusted to the date of termination. Lessee shall not because of such
condemnation assert any claim against Lessor or the condemning authority for any
compensation because of such condemnation, and Lessor shall be entitled to
receive the entire amount of any award without deduction for any estate of
interest or interest of Lessee. If a substantial portion of the Premises,
Building or the Lot is so Condemned, Lessor at its option may terminate this
Lease. If Lessor does not elect to terminate this Lease, Lessor shall, if
necessary, promptly proceed to restore the Premises or the Building to
substantially its same condition prior to such partial condemnation, allowing
for the reasonable effects of such partial condemnation, and a proportionate
allowance shall be made to Lessee, as reasonably determined by Lessor, for the
Rent corresponding to the time during which, and to the part of the Premises of
which, Lessee is deprived on account of such partial condemnation and
restoration. Lessor shall not be required to spend funds for restoration in
excess of the amount received by Lessor as compensation awarded.

29. ENVIRONMENTAL MATTERS/HAZARDOUS MATERIALS: As used in this Lease, the term
"Hazardous Materials" shall mean and include any substance that is or contains
petroleum, asbestos, polychlorinated byphenyls, lead, or any other substance,
material or waste which is now or is hereafter classified or considered to be
hazardous or toxic under any federal, state or local law, rule, regulation or
ordinance relating to pollution or the protection or regulation of human health,
natural resources or the environment (collectively "Environmental Laws") or
poses or threatens to pose a hazard to the health or safety of persons on the
Leased Premises or any adjacent property.

     Lessee agrees that during its use and occupancy of the Leased Premises it
will not permit Hazardous Materials to be present on or about the Leased
Premises except in a manner and quantity necessary for the ordinary performance
of Lessee's business and that it will comply with all Environmental Laws
relating to the use, storage or disposal of any such Hazardous Materials.

     If Lessee's use of Hazardous Materials on or about the Leased Premises
results in a release, discharge or disposal of Hazardous Materials on, in, at,
under, or emanating from, the Leased Premises or the property in which the
Leased Premises are located, Lessee agrees to investigate, clean up, remove or
remediate such Hazardous Materials in full compliance with (a) the requirements
of (i) all Environmental Laws and (ii) any governmental agency or authority
responsible for the enforcement of any Environmental Laws; and (b) any
additional requirements of Lessor that are reasonably necessary to protect the
value of the Leased Premises or the property in which the Leased Premises are
located. Lessor shall also have the right, but not the obligation, to take
whatever action with respect to any such Hazardous Materials that it deems
reasonably necessary to protect the value of the Leased Premises or the property
in which the Leased Premises are located. All costs and expenses paid or
incurred by Lessor in the exercise of such right shall be payable by Lessee upon
demand.

     Upon reasonable notice to Lessee, Lessor may inspect the Leased Premises
for the purpose of determining whether there exists on the Leased Premises any
Hazardous Materials or other condition or activity that is in violation of the
requirements of this Lease or of any Environmental Laws. The right granted to
Lessor herein to perform inspections shall not create a duty on Lessor's part to
inspect the Leased Premises, or liability on the part of Lessor for Lessee's
use, storage or disposal of Hazardous Materials, it being understood that Lessee
shall be solely responsible for all liability in connection therewith.

     Lessee shall surrender the Leased Premises to Lessor upon the expiration or
earlier termination of this Lease free of debris, waste or Hazardous Materials
placed on or about the Leased Premises by Lessee or its agents, employees,
contractors or invitees, and in a condition which complies with all
Environmental Laws.

     Lessee agrees to indemnify and hold harmless Lessor from and against any
and all claims, losses (including, without limitation, loss in value of the
Leased Premises or the property in which the Leased Premises are located),
liabilities and expenses (including reasonable attorney's fees) sustained by
Lessor attributable to (i) any Hazardous Materials placed on or about the Leased
Premises by Lessee or its agents, employees, contractors or invitees or (ii)
Lessee's breach of any provision of this Section 29.

     Notwithstanding anything in this Paragraph 29 to the contrary, Lessee shall
not be responsible for the clean up or remediation of, and shall not required to
indemnify Lessor against, any costs or liabilities attributable to, Hazardous
Materials placed on or about the Premises (i) prior to the Commencement Date by
third parties not related to Lessee or its agents, employees, partners,
shareholders, directors, invitees or independent contractors (collectively
("Agents"), or (ii) by Lessor at any time, except in either case to


                                       15
<PAGE>   16
the extent that Lessee or its Agents have contributed to or exacerbated the
presence of such Hazardous Materials.

     The provisions of this Section 29 shall survive the expiration or earlier
termination of this Lease.

30.  FINANCIAL STATEMENTS:  Lessee, for the reliance of Lessor, any lender
holding or anticipated to acquire a lien upon the Premises, the Building or the
Park or any portion thereof, or any prospective purchaser of the Building or the
Park or any portion thereof, within ten (10) days after Lessor's request
therefor, but not more often than once annually so long as Lessee is not in
default of this Lease, shall deliver to Lessor the then current financial
statements of Lessee (including interim periods following the end of the last
fiscal year for which annual statements are available) which statements shall be
prepared or compiled by a certified public accountant and shall present fairly
the financial condition of Lessee at such dates and the result of its operations
and changes in its financial positions for the periods ended on such dates. If
an audited financial statement has not been prepared, Lessee shall provide
Lessor with an unaudited financial statement and/or such other information,
prepared in accordance with generally accepted accounting principles
consistently applied ("GAAP"), which reflects the financial condition of Lessee.
If an audited financial statement has been prepared, and if Lessor so requests,
Lessee shall deliver to Lessor an opinion of a certified public accountant,
including a balance sheet and profit and loss statement for the most recent
prior year, all prepared in accordance with GAAP. Lessor shall keep Lessee's
financial statements confidential, except that Lessor shall have the right to
disclose such statements to Lessor's partners, actual and prospective lenders,
actual and prospective purchasers, consultants and advisors, including
accountants and attorneys, and otherwise as required by law or legal process.
Any and all options granted to Lessee hereunder shall be subject to and
conditioned upon Lessor's reasonable approval of Lessee's financial condition at
the time of Lessee's exercise of any such option. Lessor shall not withhold such
approval provided that (a) Lessee shall have had positive cash flow from
operations for the twelve (12) month period prior to the exercise of such
option, as shown on audited financial statements delivered to and approved by
Lessor, or (b) Lessee provides Lessor with other evidence satisfactory to Lessor
in Lessor's good faith discretion of Lessee's continuing financial viability and
ability to perform its obligations under this Lease throughout the term or
period covered by such option.

31.  GENERAL PROVISIONS:

     (i)    TIME.  Time is of the essence in this Lease and with respect to each
and all of its provisions in which performance is a factor.

     (ii)   SUCCESSORS AND ASSIGNS.  The covenants and conditions herein
contained, subject to the provisions as to assignment, apply to and bind the
heirs, successors, executors, administrators and assigns of the parties hereto.

     (iii)  RECORDATION. Lessee shall not record this Lease or a short form
memorandum hereof without the prior written consent of the Lessor.

     (iv)   LESSOR'S PERSONAL LIABILITY.  The liability of Lessor (which, for
purposes of this Lease, shall include Lessor and the owner of the Building if
other than Lessor) to Lessee for any default by Lessor under the terms of this
Lease shall be limited to the actual interest of Lessor and its present or
future partners in the Premises or the Building and Lessee agrees to look solely
to the Premises for satisfaction of any liability and shall not look to other
assets of Lessor nor seek any recourse against the assets of the individual
partners, directors, officers, shareholders, agents or employees of Lessor; it
being intended that Lessor and the individual partners, directors, officers,
shareholders, agents or employees of Lessor shall not be personally liable in
any manner whatsoever for any judgment or deficiency. The liability of Lessor
under this Lease is limited to its actual period of ownership of title to the
Building, and Lessor shall be automatically released from further performance
under this Lease and from all further liabilities and expenses hereunder upon
transfer of Lessor's interest in the Premises or the Building. Lessee agrees to
attorn to any entity purchasing or otherwise acquiring the Premises.

     (v)    SEPARABILITY.  Any provisions of this Lease which shall prove to be
invalid, void or illegal shall in no way affect, impair or invalidate any other
provisions hereof and such other provision shall remain in full force and
effect.

     (vi)   CHOICE OF LAW.  This Lease shall be governed by the laws of the
State of California.

     (vii)  ATTORNEYS' FEES.  If either party hereto fails to perform any of its
obligations under this Lease or if any dispute arises between the parties hereto
concerning the meaning or interpretation of any provision of this Lease, then
the defaulting party or the party not prevailing in such dispute, as the case
may be, shall pay any and all costs and expenses incurred by the other party on
account of such default and/or in enforcing or establishing its rights
hereunder, including, without limitation, court costs and

                                       16
<PAGE>   17
reasonable attorneys' fees and disbursements. Any such attorneys' fees and other
expenses incurred by either party in enforcing a judgment in its favor under
this Lease shall be recoverable separately from and in addition to any other
amount included in such judgment, and such attorneys' fees obligation is
intended to be severable from the other provisions of this Lease and to survive
and not be merged into any such judgment.

     (viii)   ENTIRE AGREEMENT. This Lease supersedes any prior agreements,
representations, negotiations or correspondence between the parties, and
contains the entire agreement of the parties on matters covered. No other
agreement, statement or promise made by any party that is not in writing and
signed by all parties to this Lease shall be binding.

     (ix)    WARRANTY OF AUTHORITY. Each person executing this agreement on
behalf of a party represents and warrants that (1) such person is duly and
validly authorized to do so on behalf of the entity it purports to so bind, and
(2) if such party is a partnership, corporation or trustee, that such
partnership, corporation or trustee has full right and authority to enter into
this Lease and perform all of its obligations hereunder.

     (x)     NOTICES. All notices and demands required or permitted to be sent
to Lessor or Lessee shall be in writing and shall be sent by United States mail,
certified and postage prepaid, or by personal delivery or by overnight courier,
addressed to Lessor at 30 Executive Park, Suite 100, Irvine, California 92714,
or to Lessee at the Premises, or to such other place as such party may designate
in a notice to the other party given as provided herein. Notice shall be deemed
given upon the earlier of actual receipt or the third day following deposit in
the United States mail.

     (xi)    JOINT AND SEVERAL. If Lessee consists of more than one person or
entity, the obligations of all such persons or entities shall be joint and
several.

     (xii)   WAIVER OF JURY TRIAL. The parties hereto shall and they hereby do
waive trial by jury in any action, proceeding or counterclaim brought by either
of the parties hereto against the other on any matters whatsoever arising out
of or in any way related to this Lease, the relationship of Lessor and Lessee,
Lessee's use or occupancy of the Premises, the Building or the Park, and/or any
claim of injury, loss or damage.

32.  SIGNS: All signs and graphics of every kind visible in or from public view
or corridors or the exterior of the Premises shall be subject to Lessor's prior
written approval and shall be subject to any applicable governmental laws,
ordinances, and regulations and in compliance with Lessor's Sign Criteria as set
forth in Exhibit D hereto and made a part hereof. Lessee shall remove all such
signs and graphics prior to the termination of this Lease. Such installations
and removals shall be made in a manner as to avoid damage or defacement of the
Premises; and Lessee shall repair any damage or defacement, including without
limitation, discoloration caused by such installation or removal. Lessor shall
have the right, at its option, to deduct from the Security Deposit such sums as
are reasonably necessary to remove such signs, including, but not limited to,
the costs and expenses associated with any repairs necessitated by such removal.
Notwithstanding the foregoing, in no event shall any: (a) neon, flashing or
moving sign(s) or (b) sign(s) which shall interfere with the visibility of any
sign, awning, canopy, advertising matter, or decoration of any kind of any other
business or occupant of the Building or the Park be permitted hereunder. Lessee
further agrees to maintain any such sign, awning, canopy, advertising matter,
lettering, decoration or other thing as may be approved in good condition and
repair at all times.

33.  MORTGAGEE PROTECTION: Upon any breach or default on the part of Lessor,
Lessee will give written notice by registered or certified mail to any
beneficiary of a deed of trust or mortgagee of a mortgage covering the Premises
who has provided Lessee with notice of their interest together with an address
for receiving notice, and shall offer such beneficiary or mortgagee a reasonable
opportunity to cure the default (which, in no event shall be more than ninety
(90) days), including time to obtain possession of the Premises by power of sale
or a judicial foreclosure, if such should prove necessary to effect a cure. If
such breach or default cannot be cured within such time period, then such
additional time as may be necessary will be given to such beneficiary or
mortgagee to effect such cure so long as such beneficiary or mortgagee has
commenced the cure within the original time period and thereafter diligently
pursues such cure to completion, in which event this Lease shall not be
terminated while such cure is being diligently pursued. Lessee agrees that each
lender to whom this Lease has been assigned by Lessor is an express third party
beneficiary hereof. Lessee shall not make any prepayment of Rent more than one
(1) month in advance without the prior written consent of each such lender,
except if Lessee is required to make quarterly payments of Rent in advance
pursuant to the provisions of Paragraph 8 above. Lessee waives the collection of
any deposit from such lender(s) or any purchaser at a foreclosure sale of such
lender(s)' deed of trust unless the lender(s) or such purchaser shall have
actually received and not refunded the deposit. Lessee agrees to make all
payments under this Lease to the lender with the most senior encumbrance upon


                                       17
<PAGE>   18
receiving a direction, in writing, to pay said amounts to such lender. Lessee
shall comply with such written direction to pay without determining whether an
event of default exists under such lender's loan to Lessor.

34.  QUITCLAIM: Upon any termination of this Lease, Lessee shall, at Lessor's
request, execute, have acknowledged and deliver to Lessor a quitclaim deed of
Lessee's interest in and to the Premises.

35.  MODIFICATIONS FOR LENDER: If, in connection with obtaining financing for
the Premises or any portion thereof, Lessor's lender shall request reasonable
modification(s) to this Lease as a condition to such financing. Lessee shall not
unreasonably withhold, delay or defer its consent thereto, provided such
modifications do not materially adversely affect Lessee's rights hereunder or
the use, occupancy or quiet enjoyment of Lessee hereunder.

36.  WARRANTIES OF LESSEE: Lessee hereby warrants and represents to Lessor, for
the express benefit of Lessor, that Lessee has undertaken a complete and
independent evaluation of the risks inherent in the execution of this Lease and
the operation of the Premises for the use permitted hereby, and that, based upon
said independent evaluation, Lessee has elected to enter into this Lease and
hereby assumes all risks with respect thereto. Lessee hereby further warrants
and represents to Lessor, for the express benefit of Lessor, that in entering
into this Lease, Lessee has not relied upon any statement, fact, promise or
representation (whether express or implied, written or oral) not specifically
set forth herein in writing and that any statement, fact, promise or
representation (whether express or implied, written or oral) made at any time to
Lessee, which is not expressly incorporated herein in writing, is hereby waived
by Lessee.

37.  COMPLIANCE WITH AMERICANS WITH DISABILITIES ACT: Lessor and Lessee hereby
agree and acknowledge that the Premises, the Building and/or the Park may be
subject to the requirements of the Americans with Disabilities Act (the "ADA"),
a federal law codified at 42 U.S.C. 12101 et seq, including, but not limited to
Title III thereof, all regulations and guidelines related thereto, and any
amendments thereof. Any Tenant Improvements to be constructed hereunder shall be
in compliance with the requirements of the ADA, and all costs incurred for
purposes of compliance therewith shall be a part of and included in the costs of
the Tenant Improvements. Lessee is responsible for conducting its own
independent investigation of this matter. Except for the construction of any
Tenant Improvements, for which Lessee shall be solely responsible for compliance
with the ADA, if any barrier removal work or other work is required to the
Building, the Common Area or the Park under Title III of the ADA, then such work
shall be performed by Lessor; provided, if such work is required under the ADA
as a result of Lessee's use of the Premises or any work or alteration made to
the Premises by or on behalf of Lessee, then such work shall be performed by
Lessor at the sole cost and expense of Lessee. Except as otherwise provided in
this provision, Lessee shall be responsible at its sole cost and expense for
fully and faithfully complying with all applicable requirements of the ADA.

38.  BROKERAGE COMMISSION: Lessee hereby represents and warrants to Lessor that
Lessee's sole contact with Lessor or with the Premises in connection with this
Lease has been directly with Lessor and the Broker (as set forth on Page 1), and
that no other broker or finder can properly claim a right to a commission or a
finder's fee based upon contacts between the claimant and Lessee. Lessee shall
indemnify, defend by counsel acceptable to Lessor, protect and hold Lessor
harmless from and against any loss, liability, suit, judgment, cost or expense,
including, but not limited to, experts' and attorneys' fees and costs, arising
from or relating to any claim for a fee or commission by any broker or finder in
connection with the Premises and this Lease other than Broker, if any.

     IN WITNESS WHEREOF, this Lease is executed on the date and year first
written above.

LESSOR:

AETNA LIFE INSURANCE COMPANY
A CONNECTICUT CORPORATION

By:  ALLEGIS REALTY INVESTORS, LLC
     ITS INVESTMENT ADVISOR

     By:  /s/ Cynthia Stevenin
          ---------------------------------
          Cynthia Stevenin, Vice President

     Date: 9/19/96
          ---------------------------------

                                       18

<PAGE>   19
LESSEE:

ADVANCED CORNEAL SYSTEMS, INC.,
A CALIFORNIA CORPORATION

By:    /s/ Robert K. Bruning
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Title: Chief Financial Officer
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Date:  9-13-96
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By:
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Title:
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Date:
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<PAGE>   20
ADVANCED CORNEAL PLAN

[FLOOR PLAN DRAWING]

SECOND FLOOR
9-11-96
<PAGE>   21
ADVANCED CORNEAL PLAN

[FLOOR PLAN DRAWING]

SECOND FLOOR
9-11-96
<PAGE>   22
EXHIBIT A
PREMISES DESCRIPTION

15279 Alton Parkway, Suite 100
Irvine, CA 92618
Approximately 12,946 Sq. Ft.

SITE PLAN

[SITE PLAN DRAWING]

<PAGE>   23
                                   EXHIBIT B

                          TENANT IMPROVEMENT AGREEMENT

Lease Date for Reference Purposes:      September 13, 1996

Lessor:                                 Aetna Life Insurance Company,
                                        a Connecticut Corporation

Lessee:                                 Advanced Corneal Systems, Inc.,
                                        a California Corporation


     The terms, provisions and conditions of this Exhibit "B" are hereby
incorporated into the Lease between the parties named above. Any capitalized
terms used herein and not otherwise defined herein shall have the meaning
ascribed to such terms as set forth in the Lease.

Lessor hereby agrees that Lessee shall have the right to use its own contractor
to perform certain improvements ("Lessee Improvements") in the Premises. Lessee
herein agrees to assume all responsibility for supervising the Lessee
Improvements and will indemnify and hold Lessor harmless with respect to any
errors or omissions and negligent acts of the general contractor and its
subcontractors. The Lessee Improvements shall be constructed in accordance with
the space plan attached hereto as SCHEDULE 1 (the "Space Plan"), and working
drawings approved by Landlord and the City of Irvine in writing. All Lessee
Improvements shall be permitted, if required by the City of Irvine, and shall be
constructed in accordance with the rules and regulations of all governing
authorities having jurisdiction. Prior to the commencement of Lessee
Improvements, Lessee shall provide Lessor a true and complete copy of the
written construction contract, evidence of Contractor's Insurance in amounts and
limits satisfactory to Lessor, a complete list of contractor's subcontractors
including address, telephone and facsimile numbers and contact name, and a copy
of any required building permit(s). Upon completion of the Lessee Improvements,
Lessee shall deliver to Lessor complete as-built plans, unconditional lien
waivers from all contractors, subcontractors and material suppliers, the
original signed permit card from the City of Irvine, an original executed
certificate of occupancy from the City of Irvine and any equipment warranties
obtained by Lessee in connection with the construction and installation of the
Lessee Improvements.


                                                        LESSOR'S INITIALS /s/CPS
                                                        LESSEE'S INITIALS /s/RKB


<PAGE>   24
                                     EXHIBIT C

                              RULES AND REGULATIONS

1.   Lessee shall not suffer or permit the obstruction of any Common Areas,
     including driveways, walkways and stairways.

2.   Lessor reserves the right to refuse access to any persons Lessor in good
     faith judges to be a threat to the safety, reputation, or property of the
     Project and its occupants.

3.   Lessee shall not make or permit any noise or odors that annoy or interfere
     with other lessees or persons having business within the Project.

4.   Lessee shall not keep animals or birds within the Project, and shall not
     bring bicycles, motorcycles or other vehicles into areas not designated as
     authorized for the same.

5.   Lessee shall not make, suffer or permit litter except in appropriate
     receptacles for that purpose.

6.   Lessee shall not alter any lock or install new or additional locks or
     bolts, without Lessor's written prior consent.

7.   Lessee shall be responsible for the inappropriate use of any toilet rooms,
     plumbing or other utilities. No foreign substances of any kind are to be
     inserted therein.

8.   Lessee shall not deface the walls, partitions or other surfaces of the
     premises of the Project.

9.   Lessee shall not suffer or permit any thing in or around the Premises or
     Building that causes excessive vibration or floor loading in any part of
     the Project.

10.  Lessee shall return all keys at the termination of its tenancy and shall be
     responsible for the cost of replacing any keys that are lost.

11.  No window coverings, shades or awnings shall be installed or used by
     Lessee, without Lessor's written prior consent.

12.  No Lessee, employee or Invitee shall go upon the roof of the Building or
     make any penetrations of the roof without Lessor's written prior consent.

13.  Lessee shall not suffer or permit smoking or carrying of lighted cigars or
     cigarettes in areas reasonably designated by Lessor or by applicable
     governmental agencies as non-smoking areas.

14.  Lessee shall not use any method of heating or air conditioning other than
     as provided by Lessor.

15.  Lessee shall not install, maintain or operate any vending machines upon the
     Premises without Lessor's written consent.

16.  The Premises shall not be used for lodging, cooking or food preparation,
     except Lessee shall have the right to use a microwave oven.

17.  Lessee shall comply with all safety, fire protection and evacuation
     regulations established by Lessor or any applicable governmental agency.

18.  Lessor reserves the right to waive any one of these rules or regulations,
     and/or as to any particular Lessee, and any such waiver shall not
     constitute a waiver of any other rule or regulation or any subsequent
     application thereof to such Lessee.

19.  Lessee assumes all risks from theft or vandalism and agrees to keep its
     Premises locked as may be required.

20.  Lessor reserves the right to make such other reasonable rules and
     regulations as it may from time to time deem necessary for the appropriate
     operation and safety of the Project and its occupants. Lessee agrees to
     abide by these and such rules and regulations.

                                   PARKING RULES

1.   Lessee shall not permit or allow any vehicles that belong to or are
     controlled by Lessee or Lessee's employees, suppliers, shippers, customers,
     or invitees to be loaded, unloaded, or parked in areas other than those
     designated by Lessor for such activities.

2.   Users of the parking area will obey all posted signs and park only in the
     areas designated for vehicle parking.

3.   Unless otherwise instructed, every person using the parking area is
     required to park and lock his own vehicle. Lessor will not be responsible
     for any damage to vehicles, injury to persons or loss of property, all of
     which risks are assumed by the party using the parking area.

4.   The maintenance, washing, waxing or cleaning of vehicles in the Common Area
     is prohibited.

5.   Lessee shall be responsible for seeing that all of its employees, agents
     and invitees comply with the applicable parking rules, regulations, laws
     and agreements.

6.   Lessor reserves the right to modify these rules and/or adopt such other
     reasonable and non-discriminatory rules and regulations as it may deem
     necessary for the proper operation of the parking area.



                                                          LESSOR'S INITIALS: CPS
                                                          LESSEE'S INITIALS: RKB


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