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                                                                 EXHIBIT 10.7(b)

                                 LEASE AGREEMENT


THE STATE OF TEXAS         )

COUNTY OF HARRIS           )

         THIS LEASE AGREEMENT ("Lease") made and entered into as of this 7th day
of June, 1996, by and between PLAZA DEL ORO BUSINESS CENTER (hereinafter called
"Landlord") and Introgen Therapeutics, Inc., a Delaware corporation and its
subsidiaries and affiliates (hereinafter called "Tenant").

                               W I T N E S S E T H

                                    ARTICLE I


         A. Leased Premises. Subject to and upon the terms and conditions set
forth herein, and each in consideration of the duties, covenants and agreements
of the other hereunder, Landlord hereby leases, demises and lets to Tenant and
Tenant hereby leases from Landlord those certain premises consisting of a space
containing an area of 2,405 square feet, more or less, (hereinafter called the
"Leased Premises") in the building known as Building A (hereinafter called the
"Building") located upon the lot, tract or parcel of land situated in Harris
County, Texas, more particularly described by metes and bounds on Exhibit "A"
attached hereto and made a part hereof for all purposes and presently designated
as PLAZA DEL ORO BUSINESS CENTER, an office-warehouse center (hereinafter called
the "Center") consisting of the building and four (4) other buildings
(hereinafter called the "Other Buildings"), all as shown on the site plan
attached hereto as Exhibit "B" and made a part hereof for all purposes. The
Leased Premises are outlined in red on the building plan attached hereto as
Exhibit "C" and made a part hereof for all purposes.

         B. Use in Common. Subject to and upon the terms and conditions set
forth herein, the use and occupancy by Tenant of the Leased Premises shall
include the use in common with other tenants in the Building and the Other
Buildings, and their employees, agents, contractors, guests and invitees, of the
common areas of the Center (hereinafter called the "Common Areas") including,
without limitation, the sidewalks, landscaped areas, service areas, automobile
driveways, service driveways, access roads and parking areas shown on Exhibit
"B", and the easements and rights of way appurtenant to the center.

                                   ARTICLE II

         A. Term. Subject to and upon the terms and conditions set forth herein,
this Lease shall continue in force for a term of One (1) year (hereinafter
called the "Term"), commencing on the 15th day of June, 1996, and expiring on
the 31st day of June, 1997. In the event that the Leased Premises should not be
ready for occupancy by the said commencement date for any reason, Landlord shall
not
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be liable or responsible for any claims, damages or liabilities in connection
therewith or by reason thereof and the commencement date of this Lease shall be
the date that the Leased Premises become ready for occupancy by Tenant in
accordance with Paragraph F(2) of Article III hereof or the date Tenant accepts
the Leased Premises, whichever shall first occur. In such event Landlord and
Tenant will, at the request of either, execute a memorandum specifying the
revised commencement date of the Term. In the event the commencement date or
revised commencement date shall be a date other than the first day of a calendar
month, the Term shall be for one (1) full year plus the number of days remaining
in the month in which the Term commences.

         B. Use. The Leased Premises are to be used and occupied by Tenant
solely for the purpose of office and laboratory use and no other purpose.

         C. Net Rentable Area. As used herein, the term "Net Rentable Area of
the Leased Premises" shall include all space within the demising walls of the
Leased Premises as measured from the mid-point of the demising walls; the term
"Net Rentable Area of the Building" shall mean all space within the exterior
walls of the Building, as measured from the mid-point of said walls; and the
term "Net Rentable Area or the Center" shall mean all space within the exterior
walls of the Building and Other Buildings, as measured from the mid-point of
said walls. Based upon said definitions and for the purposes hereof, the Net
Rentable Area of the Leased Premises shall be deemed to be Seven and Nine One
Hundredths percent (7.9%) of the Net Rentable Area of the Building and the Net
Rentable Area of the Leased Premises shall be deemed to be One and Fifty-Four
One Hundredths percent (1.54%) of the Net Rentable Area of the Center.

         D. Base Rental and Security Deposit.

                  (a) Tenant promises and agrees to pay to Landlord, annually
throughout the Term, subject to adjustments as hereinafter provided, base rental
(hereinafter called the "Base Rental") in the amount of Twenty-four Thousand and
no/100 Dollars ($24,000.00). Base rental shall be due and payable in twelve (12)
equal monthly installments of Two Thousand and no/100 Dollars ($2,000.00) each,
on the first day of each calendar month during each year of the Term, and Tenant
hereby agrees to so pay such rent to Landlord at Landlord's address as provided
herein, monthly in advance, without demand, deduction or set-off. If the Term
commences on other than the first day of a calendar month, Tenant shall pay on
such commencement date a pro rata payment which shall be in addition to the full
monthly installments payable during the Term. In accordance with the terms of
this paragraph D of Article II, payment has been made and receipt is hereby
acknowledged of an amount sufficient to cover Base Rental as due and payable for
the first full calendar month and prorated rent for any prior partial month of
the Term.

                  (b) In addition, Tenant agrees to deposit with Landlord on the
date hereof the sum of Two Thousand and no/100 Dollars ($2,000.00), which sum
shall be held by Landlord, without obligation for interest, as security for the
performance of Tenant's covenants and obligations under this Lease, it being
expressly understood and agreed that such deposit is not an advance rental
deposit or a measure of Landlord's damages in case of Tenant's default. Upon the
occurrence of any event of default by Tenant, Landlord may, from time to time,
without prejudice to any other remedy provided


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herein or provided by law, use such funds to the extent necessary to make good
any arrears of rent or other payments due Landlord hereunder, and any other
damage, injury, expense or liability caused by such event of default; and Tenant
shall pay to Landlord on demand the amount so applied in order to restore the
security deposit to its original amount. Although the security deposit shall be
deemed the property of Landlord, any remaining balance of such deposit shall be
returned by Landlord to Tenant at such time after termination of this Lease that
all of Tenant's obligations under this Lease have been fulfilled.

         E. Base Rental Adjustment. Base Rental may be increased or decreased
throughout the Term as follows:

                  1. For all purposes hereof, "Base Year" shall mean the
calendar year 1995.

                  2. Base Rental includes a component consisting of the Basic
Cost (as hereinafter defined) and the Basic Cost for the Base Year is hereby
stipulated to be One and 30/100 Dollars ($1.30) per square foot of Net Rentable
Area contained in the Center.

                  3. Within sixty (60) days after the commencement of each
calendar year (except the Base Year) during the Term, Landlord shall provide
Tenant with a written estimate of the Basic Cost for such calendar year, and the
Base Rental for such calendar year shall be increased by the amount, if any, of
the excess of Tenant's proportionate share of the Basic Cost for the Base Year,
but in no event shall there be any Base Rental Adjustment during the primary
lease term.

                  4. Within one hundred eighty (180) days after the end of each
calendar year (except the Base Year) of the Term, Landlord shall furnish Tenant
with a statement showing the actual Basic Cost for the calendar year just ended.
An amount equal to the difference between Tenant's proportionate share of the
actual Basic Cost and Tenant's proportionate share of the estimated Basic Cost
for the calendar year just ended shall be paid by Landlord to Tenant or by
Tenant to Landlord, as appropriate, within fifteen (15) days of the delivery of
such statement, to the end that Landlord shall receive, and Tenant shall pay, as
a portion of Base Rental for each calendar year during the Term, Tenant's
proportionate share of any increases in the Basic Cost over the Basic Cost for
the Basic Year. The obligations of Landlord and Tenant regarding any adjustment
for increases in the Basic Cost for the year in which this lease expires or
otherwise terminates shall expressly survive the termination of this Lease.

                  5. Any adjustment of Base Rental shall operate retroactively
and be effective as of the first day of each calendar year.

                  6. As an alternative to the procedure described in
subparagraphs 3, 4, and 5 above, Landlord, at its sole option, may elect to
invoice Tenant annually, within one hundred eighty days (180) days after the end
of each calendar year (except the Base Year) during the Term, for the amount, if
any, of the excess of Tenant's proportionate share of the Basic Cost for the
calendar year just ended over the Basic Cost for the Base Year, and Tenant shall
pay said amount as additional rent within fifteen (15) days after receipt of
such invoice from Landlord.


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                  7. For all purposes hereof, "Tenant's proportionate share"
shall be that proportion which the Net Rentable Area of the Leased Premises
bears to the Net rentable area of the Center.

                  8. Notwithstanding anything contained herein to the contrary,
in no event shall Base Rental be reduced below the amounts specified in Article
II, Paragraph D hereof.

         F. Past Due Rent and Charges. Landlord shall be entitled to collect a
late charge of $5.00 for each day from the date due until the date paid on all
installments of Base Rental or other charges payable by Tenant hereunder which
are not paid within five (5) days after the date due. In addition, all
installments of Base Rental or other charges payable by Tenant hereunder which
are not paid within thirty (30) days after the date due shall bear interest at
the rate of eighteen percent (18%) per annum from the date due until the date
paid. Any election of Landlord to accept the payment of past due installments of
Base Rental and/or other charges payable by Tenant hereunder without the payment
of the late charge and/or interest described herein shall not be deemed a waiver
of Landlord's right to collect said late charge and/or interest in the event of
any subsequent past due installment or installments of Base Rental and/or other
charges payable by Tenant hereunder.

         G. Basic Cost. As used herein, the term "Basic Cost" shall consist of
the following:

                  1. Cost of Landlord's fire and extended coverage and liability
insurance applicable to the Center and the buildings therein;

                  2. All general and special taxes, except taxes based on
income, impositions, assessments and governmental charges, or any substitutions
in lieu thereof, imposed upon the Center and buildings therein, whether federal,
state, county or municipal, and whether by taxing districts or authorities
presently existing or by others subsequently created; and

                  3. Common Area Maintenance Costs, as defined in Article III,
Paragraph C hereof.

         H. Audit. Tenant, at its expense, shall have the right, once each
calendar year, upon thirty (30) days prior written notice to Landlord, to audit
Landlord's books and records relating to this Lease for the Base Year and any
calendar year thereafter.


                                   ARTICLE III

Landlord covenants and agrees with Tenant:

         A. Utilities. To provide, at Landlord's cost, normal water, sanitary
sewer, electricity and gas connections to the Leased Premises from the nearest
water, sanitary sewer, electric and gas mains, laterals and/or trunk lines
serving the Center. Any interruptions or cessation of said services shall not
render Landlord liable in any respect for injury, damage or loss to persons or
property, except in the case of said interruption being caused by Landlords
negligent acts, shall not be


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construed as an eviction of Tenant, shall not work an abatement of rent, and
shall not relieve Tenant from fulfillment of any covenant or agreement hereof.

         B. Maintenance and Repairs to Building. Subject to the provisions of
Article IV, provisions Paragraph C and Article V, Paragraph F hereof, to make,
at Landlord's expense, all repairs and replacements, structural or otherwise,
necessary to keep the roof, foundation and the structural soundness of the
exterior walls of the Building in good repair; provided, however, that the term
"exterior walls" as used herein shall not include any items for which Tenant is
responsible under Article IV, Paragraph C, and nothing contained in this Article
III, Paragraph B shall require Landlord to paint the interior of the Leased
Premises or the interior of the Building or to make any other repairs or
replacements to the Building at any time except when such other repairs and
replacements are required under this Article III, Paragraph B, or under the
provisions of Article V, Paragraph F hereof. Landlord's liability hereunder
shall be limited to the cost of such repairs. Any entry for the purpose of
making such repairs shall not affect Tenant's obligations under this Lease and
shall not constitute any ground for abatement of any rentals or other charges
payable by Tenant hereunder, and Tenant hereby expressly waives all claims for
inconveniences, disturbance, interruption and/or loss of Tenants business or
other damages due to said entry, unless caused by the gross negligence of
Landlord or its agents.

         C. Common Area Maintenance and Repairs. To keep swept in a neat, clean
condition the common areas, untidiness due to normal and usual use only
excepted, and in addition, to (i) repair the Common Areas, including, without
limitation, surface of the driveways, sidewalks, service areas, and parking
areas, (ii) keep the parking and service areas stripped, and (iii) maintain the
landscaped areas, including landscape replacement. Said maintenance and repairs
shall include, as more specifically set forth below, all repairs and
replacements and the supplies and materials therefor, which in Landlord's
reasonable judgment are necessary to preserve the utility of the Common Areas in
the condition same were in at the time of completion, reasonable wear and tear
only excepted.

                  As used herein, "Common Area Maintenance Costs" shall mean all
costs and expenses of every kind paid or incurred during the Term in connection
with the operation and upkeep of Common Areas, including, without limitation,
sidewalks, landscaped areas, service areas, automobile driveways, service
driveways, parking areas, signs, lighting, sweeping, cleaning, draining and
striping the parking and service areas, and where necessary, the cost of
replacing any of said common facilities, and the cost of policing and protecting
same. In addition to the foregoing, and without limiting the generality thereof,
the Common Area Maintenance Costs shall include: wages paid to employees or
contractors of Landlord hired for the purpose of maintaining the Common Areas,
premiums for common area workmen's compensation and common area employees'
liability insurance, common area unemployment taxes, common area Social Security
taxes, personal property taxes for Common Areas, common area licenses and
permits, common area supplies, electricity, lighting fixtures and bulbs, and
rentals paid for equipment rented or leased or used in the operation and
maintenance thereof and a fee to be paid Landlord, or Landlord's designee, for
the administrative expense of maintaining the Common Areas, provided that said
fee shall not exceed five percent (5%) of all other common Area Maintenance
Costs for any calendar year.


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         D. Keys. To furnish Tenant, free of charge, with two (2) keys for each
door entering the Leased Premises. Additional keys will be furnished at a charge
by Landlord equal to its cost plus fifteen percent (15%) on an order signed by
Tenant or Tenant's authorized representative. All such keys shall remain the
property of Landlord. No additional locks shall be allowed on any door of the
Leased Premises without the written consent of Landlord, and in the event
Landlord gives its consent, Tenant shall furnish Landlord a key for each such
additional lock upon the installation thereof. Tenant shall not make, or permit
to be made, any duplicate keys except those furnished by Landlord. Upon
termination of this Lease, Tenant shall surrender to Landlord all keys to the
Leased Premises and give to Landlord the combination of all locks for safes,
safe cabinets and vault doors, if any, in the Leased Premises.

         E. Signs. That Tenant shall have the right to install sign letters,
numerals, emblems, trademarks, insignia or other designs upon certain areas and
spaces designated by Landlord on the Leased Premises in accordance with the sign
criteria set forth in Exhibit "D" attached hereto and made a part hereof for all
purposes.

         F. Construction. That the condition of the Leased Premises as of the
date of this Lease is such that the Shell of the Building (as hereinafter
defined) and certain Leasehold Improvements are completed. In this connection,
Landlord and Tenant have agreed and do hereby agree as follows:

                  1. The definitions set out below apply to the following terms
as those terms are used in this Lease, unless the context clearly requires a
different meaning:

                           (a) "Shell of Building" means the building,
consisting of beams, structural steel, exterior walls, roof, paint on exterior
walls and trim, interior finish and paint in certain areas of the Building that
are common to the Building as a whole, such as entries and corridors exterior to
the Leased Premises and certain utility service lines, including electrical and
sanitary sewer service to the Building, sidewalks, parking area and other common
areas and facilities, all as shown on the approved plans and specifications (as
hereinafter defined).

                           (b) "Leasehold Improvements" means all existing
improvements as shown on the architectural floor plan attached hereto as
"Exhibit "E" and made a part hereof for all purposes and any other improvements
required by Tenant and approved by Landlord.

                  2. Subject to the foregoing terms and agreements of this
Lease, Tenant agrees to complete any additional improvements in a good and
workmanlike manner and in accordance with the plans and specifications furnished
by Tenant and approved by Landlord. All improvements or changes in addition to
the existing Leasehold Improvements on Exhibit "E" shall be for Tenant's account
and Tenant shall pay the cost thereof. Tenant agrees that upon expiration of
this lease, at Landlord's request Tenant shall, at Tenant's expense, cause the
removal of any portion of any additional leasehold improvements made by Tenant,
and repair any affected part of the existing leasehold improvements.


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                  3. The rights of Tenant in and to the Leasehold Improvements,
when completed, shall be limited to Tenant's leasehold estate therein, which is
a possessory right, subject to all of the terms and conditions of this Lease,
and the Leasehold Improvements shall constitute a part of the fee remainder,
subject to Tenant's right of possession and use during the Term, and
notwithstanding that Tenant may have contributed to the initial cost or to the
subsequent repair or replacement thereof. Under no circumstances shall Tenant's
rights in the Leasehold Improvements entitle Tenant to collaterally assign,
grant a security interest in or remove the Leasehold Improvements, or any part
thereof, at any time during the Term.

         G. Quiet Enjoyment. That so long as Tenant shall pay all Base Rental,
additional rent and other charges payable by Tenant hereunder, and shall observe
and abide by all reasonable regulations regarding use of the Center, the
Building, the Other Buildings and the Common Areas, and shall observe and
perform all of the covenants on Tenant's part to be observed and performed
hereunder, then, subject to the limitations upon the title to the Center set
forth on Exhibit "G" attached hereto and made a part hereof for all purposes,
Tenant shall peaceably and quietly hold and enjoy the Leased Premises for the
entire term without interruption by Landlord or any person or persons lawfully
or equitably claiming by, through or under Landlord. It is understood and agreed
that this covenant and any and all other covenants of Landlord contained in this
Lease shall be binding upon Landlord and its successors and assigns only with
respect to breaches occurring during its and their respective ownership of the
Landlord's interest hereunder. In addition, Tenant specifically agrees to look
solely to Landlord's interest in the Center for the recovery of any judgment
from Landlord, it being expressly agreed and understood that Landlord shall
never be personally liable for any such judgment.

         H. Parking. Tenant shall have the right to six (6) parking spaces
located in the Center as shown in Exhibit B hereto. Landlord may designate
additional parking at an easement adjacent to Building B and at the rear of
Tenants Leasehold. Landlord reserves the right from time to time to assign, or
reassign, the location of such parking spaces in any manner that Landlord in
Landlord's sole discretion, deems more beneficial to the operation of the
Center. Tenant agrees that it will employ reasonable efforts to prevent the use
by Tenant's employees and visitors of any parking spaces allocated to other
tenants. Landlord reserves the right to promulgate rules and regulations for the
use of all parking areas at any time during the term of this Lease.

                                   ARTICLE IV

Tenant covenants and agrees with Landlord:

         A. Payment. To pay all Base Rental, additional rental and other charges
provided to be paid to Landlord hereunder at the times and in the manner herein
provided.

         B. Utility Payments. To pay all charges for water, sanitary sewer,
electricity, gas and telephone service used in, on or about the Leased Premises
and all maintenance charges for said utilities as follows:


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                  1. Tenant promises and agrees to pay directly to the utility
                     companies, within thirty (30) days after receipt statement
                     for services, all charges for electricity, gas and
                     telephone service used in, on or about the Leased Premises
                     and all maintenance charges therefor.

                  2. Tenant promises and agrees to pay Landlord, within ten (10)
                     days after receipt of Landlord's statement therefor,
                     Tenant's proportionate share of all charges for water and
                     sanitary sewer services furnished to the Building provided,
                     however, that landlord reserves the right, at its sole
                     option, to install a separate flow meter on and for the
                     Leased Premises, and in such event, Tenant promises and
                     agrees to pay to Landlord within ten (10) days after
                     receipt of Landlord's statement therefore all charges for
                     water and sanitary sewage services furnished to the Leased
                     Premises. For purposes of the forgoing, Tenant's
                     proportionate share of all water and sanitary sewer charges
                     furnished to the Building shall be that proportion which
                     the Net Rentable area of the Leased Premises bears to the
                     Net Rentable Area of the Building, less any portion thereof
                     separately metered.

         C. Repairs and replacements. To make, at its sole cost and expense, all
repairs and replacements to the Building (except repairs and replacements for
which Landlord is expressly obligated under Article III, Paragraph B) and the
Leased Premises, and the fixture, appurtenances and equipment therein, as and
when needed to preserve them in good working order and condition.
Notwithstanding Landlord's obligations under Article III Paragraph B any damage
or injury to the Leased premises and to its fixtures, appurtenances and
equipment caused by Tenant's negligence or the negligence of Tenant's employees,
agents contractors, guests or invitees, or moving property in or out of the
Building by installation or removal of furniture, fixtures or other property,
shall be repaired or replaced promptly by Tenant at its sole cost and expense,
which repairs and replacements shall be in quality and class equal to the
original work or installations.

         Without limiting the generality of the foregoing, Tenant shall, at its
sole cost and expense, repair and/or replace all damaged windows, glass and
plate glass, doors, any specific office or warehouse front, interior walls, any
finish conditioning equipment and systems in and for the Leased Premises, water,
sanitary sewer, electricity and gas lines to the point of connection to the
Leased Premises (provided that any damage to the mains, laterals or trunk lines
from the point of connection to the Leased Premises caused by the Tenant or its
employees, agents, contractors, guests or invitees, shall be Tenant's
responsibility), plumbing and electrical work and fixtures, and shall suffer and
permit no waste; provided however, that Tenant shall not be obligated to repair
any damage caused by fire, tornado, or other casualty covered by fire and
extended coverage provisions of Landlord's fire and extended coverage insurance
policy.

         If Tenant fails to perform Tenant's obligations under this Article IV,
Paragraph C, Landlord may, at Landlord's option, enter upon the Leased Premises
after ten (10) days prior written notice to Tenant, and cause all necessary
repairs and/or replacements to be made, and the cost thereof shall be due and
payable to Landlord within ten (10) days after receipt of Landlord's statement
therefor.


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         D. Tenant's Property and Liens. That Tenant shall be responsible for
and shall pay, before same become delinquent, all federal, state, country, and
municipal taxes assessed against any leasehold interest and all personal
property of any kinds owned by or placed in, on or about the Leased premises by
Tenant during the Term, including, without limitation, any additional leasehold
improvements or alterations made by Tenant, and all furnishings, equipment,
trade fixtures, inventory, and merchandise of Tenant. Tenant shall neither
permit nor suffer an involuntary lien to be filed or affixed against the Leased
Premises, any part thereof or any fixture attached thereto, whether same be
movable or not, and shall not voluntarily grant any lien or security interest
therein. In the event any such voluntary or involuntary lien, including, without
limitation, any mechanic's lien and tax lien, shall be filed and/or affixed
against the Leased Premises, any part thereof of any fixture attached thereto,
including, without limitation, items of work and improvement comprising the
interior (notwithstanding that same may or might constitute a part of the fee
remainder), and Tenant has not caused same to be released and discharged of
record within twenty (20) days after notice and demand by Landlord for the
release and discharge thereof, Landlord may, at its option, pursue the rights
and remedies provided in Article V, Paragraph H hereof without the necessity of
any further notice or demand, or Landlord may cause same to be vacated or
released either by paying the amount claimed to be due or by procuring the
release of such lien by giving security or in such other manner provided by law.
If Landlord elects to effect the release and discharge of record of such lien,
Tenant shall repay to Landlord, immediately upon demand, all such sums disbursed
or deposited by Landlord pursuant to the foregoing provision of this paragraph.
Nothing contained herein, however, shall imply any consent or agreement on the
part of Landlord or anyone holding under Landlord to subject Landlord's interest
to liability under any mechanics or other lien law, regardless of whether the
performance of the furnishing of such work, labor, services or materials to
Tenant or anyone holding under Tenant shall have been consented to by Landlord.

         All furnishings, equipment, trade fixtures and any other property
necessary for the proper operation of Tenant's business shall be furnished and
installed by Tenant at its sole cost and expense unless specifically provided to
the contrary herein. All property stored or warehoused at the Leased Premises
shall be stored or warehoused at the risk of Tenant only, and Tenant shall hold
Landlord harmless from any claims arising out of damage to the same, including
subrogation claims by Tenant's insurer, if any, unless such damage shall be
caused by the gross negligence of Landlord.

         E. Surrender. Not to commit or allow any waste or damage to be
committed on any portion of the Leased Premises, the Building, the Other
Buildings, or the Center, and at the expiration or earlier termination of this
Lease, to surrender the Leased Premises to Landlord in as good condition as at
the date of possession by Tenant, ordinary wear and tear expected; and upon such
expiration or earlier termination of this Lease, Landlord shall have the right
to re-enter and resume possession of the Leased Premises.

         F. Assign and Sublet. Not to assign this Lease or sublet the Leased
Premises, or any portion thereof, without the prior written consent of Landlord,
and any attempted assignment or subletting without such consent, whether express
or by operation of law, shall be void. Landlord and Tenant specifically agree
that in the event of any approved assignment or subletting, the rights of any
such assignee or subtenant of Tenant herein to the use and occupancy of the
Leased Premises shall be


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subject to all of the terms, conditions and provisions of this Lease, including,
without limitation, restrictions on use and the covenant to pay Base Rental,
additional rent and other charges payable by Tenant hereunder, and Landlord may
collect Base Rental, additional rent and other charges payable by Tenant
hereunder directly from such assignee or subtenant and apply the amount so
collected to the rents herein reserved. Any consent to or recognition of any
such assignment or subletting, or a release of Tenant, or any guarantor or
Tenant's performance hereunder, from further performance by Tenant of covenants
undertaken to be performed by Tenant herein, and Tenant will remain liable and
responsible for all rents and other obligations herein imposed upon Tenant. In
the event Landlord shall sell or convey the Leased Premises, the grantee shall
take such property subject to the terms hereof and shall be subrogated to all
for the rights and privileges of Landlord hereunder.

         G. Alterations. Not to make or allow to be made any alterations or
physical additions in or to the Leased Premises without first obtaining the
written consent of Landlord. Upon the termination of this Lease by lapse of time
or otherwise, all such alterations, physical additions or improvements, and/or
fixtures furnished and installed by Tenant which are permanently attached to the
Leased Premises, including all heating and air conditioning equipment, shall, at
Landlord's option, become a part of the fee remainder; or in the alternative,
Landlord may require Tenant to remove such property, as well as Tenant's
moveable personal property, promptly upon the termination of this Lease and
repair, at Tenant's sole expense, any damage to the Leased Premises caused
thereby and Tenant's obligation to so repair shall expressly survive the
terminate of this Lease.

         H. Lawful use. Not to occupy or use, or permit the occupancy or use of,
the Leased Premises or any portion thereof for any purpose other than that
stated in Paragraph B of Article II hereof and in no event for any business or
purpose which is unlawful, disreputable or deemed to be extra hazardous on
account of fire, or permit anything to be done which would in any way increase
the rate of fire insurance coverage on the Building and/or its contents.

         I. Rules. To comply with all reasonable laws, ordinances, orders, rules
and regulations (state, federal, municipal and other agencies or bodies having
any jurisdiction thereof) in effect now or in the future, relating to the use,
condition or occupancy of the Leased Premises. Tenant will comply with all rules
of the Building, the Other Buildings and the Center, which may be adopted by
Landlord from time to time for the safety, care and cleanliness of the Leased
Premises, the Building, the Other Buildings and the Center, and for preservation
for good order therein, all of which will be sent by Landlord to Tenant in
writing and shall be thereafter carried out and observed by Tenant.

         J. Entry. To permit Landlord or its agents or representatives the right
of entry into and upon any part of the Leased Premises at all reasonable hours
to inspect same, clean or make repairs, alterations or additions thereto, as
Landlord may deem necessary or desirable, and Tenant shall not be entitled to
any abatement or reduction of rent by reason of such entry. During the period
that is six (6) months prior to the expiration of the Term, Landlord and
Landlord's authorized agents and representatives shall have the right to enter
the Leased Premises at any time during reasonable business hours for the purpose
of showing the Leased Premises and shall have the right to erect on the Leased
Premises a suitable sign indicating the Leased Premises are available.


                                      -10-
<PAGE>   11
         K. Nuisance. To conduct its business and control its agents, employees,
contractors, invitees and guests in such manner as not to create any nuisance or
to interfere with, annoy or disturb any other tenant or Landlord in its
operation of the Building, the Other Buildings and the Center.

                                    ARTICLE V

         Landlord and Tenant mutually covenant and agree as follows:

         A. Subordination. This Lease is expressly subject, subordinate and
inferior to the matters referred to on Exhibit "G" hereto, as presently or
hereafter affecting the Building, the Other Buildings or Center, and any future
expansion thereof or additions thereto, and to any first mortgage, deed of
trust, security agreement or other lien or encumbrance whatever resulting from
any method of financing or refinancing, presently or henceforth placed upon the
Building or Center, and any future expansion thereof or additions thereto, and
to all advances of money or other value heretofore or hereafter made upon the
Building, the Other Buildings or Center, and to any future expansion thereof or
additions thereto; provided, however, the foregoing provisions of this Paragraph
A of Article V to the contrary notwithstanding, if Landlord or the holder of any
such mortgage, deed of trust, security agreement or other lien or encumbrance
shall elect to make this lease superior, then this lease shall be deemed
superior to any such mortgage, deed or trust, security agreement or other lien
or encumbrance. Without limiting the generality or effect of the foregoing
provisions of this Paragraph A of Article V, Tenant covenants and agrees,
promptly upon request of Landlord, to execute and deliver in the recordable form
provided by Landlord, an acknowledgment of Lease subordination or superiority,
as the case may be, according to the election made by Landlord, or the holder of
such mortgage, deed of trust, security agreement or other lien or encumbrance as
hereinabove provided. Subject to the foregoing provisions of this Paragraph A of
Article V, Landlord reserves the right, without notice to or consent of Tenant,
to assign, pledge or mortgage this Lease and/or any and all rents hereunder as
security for the payment of any mortgage loan, deed of trust loan or other
method of financing or refinancing.

         B. Non-Disturbance. In the event any such mortgage is foreclosed, or in
the event of exercise of the power of sale under any such deed of trust, the
purchaser at said foreclosure or trustee's sale shall be considered the landlord
hereunder and shall be deemed to assume and to agree to perform the duties of
Landlord hereunder, and so long as Tenant complies with all of the terms and
provisions of this Lease, and is not in default hereunder, this lease shall not
be affected by said foreclosure or trustee's sale, and said purchaser shall
recognize Tenant's rights to continue to rights hereunder, and Tenant will
attorn to said purchaser and will recognize said purchaser as the owner and
landlord under this Lease.

         C. Eminent Domain - Total Taking. In the event of a taking of the Lease
Premises or damage related to the exercise of the power of eminent domain by any
agency, authority, public utility, person, or corporation or entity empowered to
condemn property ("Taking") of the entire Leased Premises or so much thereof as
to prevent or substantially impair their use by Tenant during the Lease term (i)
the rights of Tenant under the Lease and the leasehold estate of Tenant in and
to the Premises shall cease and terminate as of the date upon which title to the
Premises, or a portion


                                      -11-
<PAGE>   12
thereof, passes to and vests in the condemner or the effective date of any order
for possession if issued prior to the date title vests in the condemner ("Date
of Taking"), (ii) Landlord shall refund to Tenant any prepaid rent, (iii) Tenant
shall pay to Landlord any rent to charges due Landlord under the Lease, each
prorated as of the Date of Taking, (iv) Tenant shall receive from the Award
those portions of the Award attributable to relocation of Tenant, improvements
to the Premises made and paid for by Tenant and trade fixtures, equipment, and
furniture of Tenant, and (v) the remainder of the Award shall be paid to and be
the property of the Landlord.

         D. Eminent Domain - Partial Taking. In the event a portion of the
leased premises shall be taken for any public or quasi-public use under any
governmental law, ordinance or regulation, or by right of eminent domain or by
purchase in lieu thereof, and this Lease is not terminated as provided in
Article V, Paragraph C above, Lessor may, at Lessor's sole risk and expense,
restore and reconstruct the building and other improvements and on the leased
premises to the extent necessary to make it reasonably tenantable. The rent
payable under this Lease during the unexpired portion of the term shall be
adjusted to such an extent as may be fair and reasonable under the
circumstances. Lessee shall have no claim to the condemnation award.

         E. Holding over. In the event of holding over by Tenant after
expiration or earlier termination of this Lease without the written consent of
Landlord, Tenant shall pay as liquidated damages double rent for the entire
holdover period. No holding over by Tenant after the Term shall operate to
extend the Term and, in the event of any unauthorized holding over, Tenant shall
indemnify Landlord against any and all claims for damages or loss resulting
therefrom, including, but not limited to, claims by any other tenant to whom
Landlord may have leased all or any part of the Leased Premises covered hereby
effective upon the expiration or earlier termination of this Lease. Any holding
over with the consent of the Landlord in writing shall thereafter constitute
this Lease a tenancy from month to month.

         F. Destruction. In the event of a fire or other casualty in the Leased
Premises or the Building, Tenant shall immediately give notice thereof to
Landlord. If the Leased Premises shall be partially destroyed by fire or other
casualty so as to render the Leased Premises untenantable, Base Rental shall
abate thereafter until such time as the Leased Premises are made tenantable by
Landlord; provided, however, that if the Leased Premises are so partially
destroyed but are only rendered partially untenantable, there shall only be a
partial abatement of Base Rental corresponding to the time and extent the Leased
Premises or any other part of the Building shall be so damaged that Landlord
shall decide not to rebuild, then Landlord shall have the right, at its sole
option, to terminate this Lease and upon notice thereof from Landlord and upon
payment of all Base Rental and additional rental owed up to the time of
destruction, this Lease shall cease and come to an end.

         G. Conveyance by Landlord. Landlord shall have the right to sell,
transfer, or assign, in whole or in part, all its rights and obligations
hereunder, and all or any part of its interest in the Building, the Other
Buildings and the Center. In the event of any such conveyance, the grantee shall
take the property subject to the terms of this Lease and shall be subrogated to
all of the rights of the Landlord hereunder and in such event, no further
liability or obligation shall thereafter accrue against Landlord hereunder.


                                      -12-
<PAGE>   13
         H. Default. In the event of any failure of Tenant to pay any rent
reserved herein or any other payment or charge due hereunder in the time and
manner provided herein, or in the event Tenant shall violate, neglect, fail to
observe, keep or perform any covenant, agreement or stipulation herein contained
on Tenant's part to be observed, kept or performed, which default shall continue
(1) for ten (10) days after notice of failure to pay rent or other payment or
charge, or (2) for thirty (30) days after notice of default on account of any
failure to perform or keep any other of the terms, conditions or covenants of
this Lease (which notice in either instance shall be given by Landlord to Tenant
in writing), or if Tenant, or any guarantor of Tenant's performance under this
Lease, shall become bankrupt or insolvent, or file any debtor proceedings or
take or have taken against them, or either of them in any court, pursuant to any
state or federal statute, a petition in bankruptcy or insolvency or
reorganization or for the appointment of a receiver or trustee of all or a
portion of Tenant's or any such guarantor's property, or if Tenant or any such
guarantor petitions for or enters into an arrangement, or if Tenant shall
abandon the Leased Premises or suffer this Lease to be taken under any writ of
execution, then, in addition to all other remedies and courses of action now and
hereafter provided by law, Landlord shall have the immediate right to re-enter
the Leased Premises and remove all personal and property therefrom, and such
property may be removed and stored in a public warehouse or elsewhere at the
cost of, and for the account of, Tenant, all without service of notice or resort
to legal process and without being deemed guilty of trespass, or becoming liable
for any loss or damage which may be occasioned thereby.

         I. Re-entry. Should Landlord elect to re-enter, as provided above, or
should Landlord take possession of the Leased premises pursuant to legal
proceedings or pursuant to any notice provided by law, Landlord may either
terminate this Lease or Landlord may from time to time thereafter make such
alterations or repairs as may be necessary in order to relet the Leased Premises
or any portion thereof, and Landlord may relet the Leased Premises or any
portion thereof for such term or terms (not to extend beyond the Term), and for
such rental or rentals and upon such other agreements and conditions as
Landlord, in its sole discretion, may deem advisable; and upon such reletting,
all rentals actually received by Landlord from such reletting shall be applied,
first, to the payment of any sum other than rent due hereunder; second to the
payment of any cost and expense of reletting, including brokerage, attorney's
fees and the cost of alterations and repairs; third, to the payment of any rent
due and unpaid hereunder; and finally, the residue, if any, shall be held by
Landlord and applied in payment of future rent, as the same may become due and
payable hereunder. If such rentals received from such reletting during any month
be less than that agreed to be paid hereunder by Tenant during that month,
Tenant shall pay any such deficiency to Landlord, such deficiency to be
calculated and paid months. No such re-entry shall be constructed as an election
by Landlord to terminate this Lease unless a written notice of such intention is
given to tenant.

         J. Termination. Notwithstanding any prior election to terminate,
Landlord may, at any time subsequent to such re-entry, elect to terminate this
Lease on account of such previous breach, and in the event of any such
termination, whether subsequent to re-entry or contemporaneous therewith, in
addition to any other remedy it may have, Landlord may recover from Tenant all
damages incurred by reason of such breach, including reasonable attorney's fees
and actual cost incurred in recovering possession of the Leased Premises, and
including a sum equal to the excess, if any, of the amount of Base Rental and
additional rent reserved in this Leased Premises for such


                                      -13-
<PAGE>   14
period, all of which amounts shall be immediately due and payable from Tenant to
Landlord. For the purpose of determining the rent which would be payable by
tenant hereunder subsequent to default, the annual rent for each year of the
unexpired portion of the Term shall be equivalent to the average Base Rental and
additional rent paid by Tenant from the commencement of the Term to the time of
default, or during the preceding three (3) calendar years, whichever period is
shorter.

         K. Attorney's Fees. In the event either Landlord or Tenant files suit
to enforce any covenant of this Lease, the party against whom final,
non-appealable judgement is rendered shall pay all costs and expenses of suit
incurred by the prevailing party, including such reasonable attorney's fees as
shall be fixed by the court.

         L. Cumulative. The rights and remedies hereinabove provided Landlord in
the event of any default by Tenant, or in the event of any act, omission, or set
of circumstances constituting default hereunder, as hereinabove provided, shall
be cumulative and not exclusive, one of the other, and further provided, each of
said rights and remedies shall be cumulative of and without prejudice to the
rights, remedies and causes of action provided Landlord by law, present or
future.

         M. Waiver. One or more waivers of any breach or violation of any
agreement, covenant or conditions herein contained shall not be deemed to be a
waiver of any subsequent violation or breach of the same or any other covenant
or condition herein contained, and the consent or approval by either party to
any act by the other, which act requires the consent or approval of the other
party, shall not be deemed to waive or render unnecessary the future requirement
of consent or approval to the same or similar act; and the subsequent acceptance
of rent or other charges hereunder shall not be deemed to be a waiver of any
preceding breach by Tenant, other than the failure of Tenant to pay the
particular rent or other charges so accepted, regardless of Landlord's knowledge
of such preceding breach at the time of acceptance of said rent or other
charges. No express covenant, term or condition of this Lease shall be deemed to
have been waived by either party, unless such waiver be in writing.

         N. Landlord's Fire Insurance. At all times during the Term, Landlord
shall cause to be maintained a policy or policies of fire and extended coverage
insurance, issued by and binding upon some licensed insurance company, covering
the Building, including the Leased Premises and Leasehold Improvements
(exclusive of contents), in an amount equal to not less than eighty percent
(80%) of the replacement cost thereof. Such insurance shall insure Landlord (and
other persons, firms or corporations as may be designated by Landlord) against
the losses provided for in said policy or policies subject to the terms and
provisions of this Lease and any first mortgage or deed of trust covering the
Building; and Tenant shall have no interest in said policy or policies or
proceeds therefrom. Landlord shall not be obligated to insure any furnishings,
equipment, trade fixtures, or other personal property which Tenant may place or
cause to be placed upon the Leased Premises, or any improvements which Tenant
may construct therein.

         O. Landlord's Liability Insurance. Likewise, Landlord shall cause to be
maintained a policy or policies of comprehensive general liability insurance
issued by and binding upon some licensed insurance company, insuring Landlord
(and such other persons, firms or corporations as may


                                      -14-
<PAGE>   15
be designated by Landlord) against loss of life, bodily injury and/or property
damage with respect to the Common Areas and the operation of the Center, subject
to the terms and provision of this Lease and any first mortgage or deed of trust
covering the Center; and Tenant shall have no interest in said policy or
policies or proceeds therefrom.

         P. Tenant's Fire Insurance. At all times during the Term, Tenant shall
keep the trade fixtures, equipment, furnishings, fixtures, improvements and any
other personal property furnished and installed by Tenant insured against loss
or damage by fire or other casualty, with fire and extended coverage insurance
in an amount equal to ninety percent (90%) of the replacement cost thereof,
written by one or more responsible insurance companies approved by Landlord and
licensed to do business in the State of Texas, which insurance companies shall
be rated not less than A+10 by Best Guide Rating, insurance Tenant, and naming
as additional insured Landlord and such other persons, firms or corporations as
are designated by Landlord. Each such policy shall be noncancellable for any
cause without first giving Landlord ten (10) days prior written notice.

         Q. Tenant's Liability Insurance. Likewise, Tenant shall maintain in
force during the Term a policy or policies of comprehensive public liability
insurance, including property damage, written by one or more responsible
insurance companies approved by Landlord and licensed to do business in Texas,
which insurance companies shall be rated not less than A+10 by Best Guide
Rating, insurance Tenant, and naming as additional insured Landlord and such
other persons, firms, or corporations as are designated by Landlord, against
loss of life, bodily injury and/or property damage with respect to the Leased
premises and the business operated therein by Tenant, in which the limit of
public liability shall not be less than FIVE HUNDRED THOUSAND AND NO/100 DOLLARS
($500,000.00) single limit bodily injury and in which the limit of property
damage liability shall be not less than ONE HUNDRED THOUSAND AND NO/100 DOLLARS
($100,000.00). Each such policy shall be noncancellable for any cause without
first giving Landlord ten (10) days prior written notice.

         R. Policies. Tenant shall deliver a copy of each such policy, or a
certificate or said insurance, to Landlord on or before the commencement date of
the Term.

         S. Hold Harmless. Tenant shall indemnify and save Landlord harmless
from and against (i) any and all costs, liability or expense arising out of the
claim of any person or persons on account of any occurrence in, on or at the
Leased Premises, Building, Other Buildings or Center resulting from the
occupancy or use of the Leased Premises by Tenant, or by any person or persons
holding under Tenant (including, without limitation and for purposes of this
Paragraph S of Article V, Tenant's guests, invitees, agents, contractors,
employees, servants, subtenants or assignees), except however, for losses or
damage caused by Landlord's gross negligence or willful misconduct; (ii) any
penalty, damage or charge incurred or imposed by reason of any violation of law
or ordinance by Tenant or any person or persons holding under Tenant; and (iii)
any and all costs, liability or expense arising out of the claim of Tenant or
any person or persons holding under tenant on account of any occurrence in, or
on or at the Leased Premises, Building, Other Buildings or Center, except
however, for losses or damage caused by Landlord's gross negligence or willful
misconduct. Further, Landlord shall not be liable or responsible to Tenant for
any loss or damage to any property or person resulting from theft, fire, act of
God, public enemy, injunction, riot, strike, insurrection, war, court order,


                                      -15-
<PAGE>   16
requisition or order of governmental body or authority, or from the acts or
omissions of occupants of other space in the Building or Other Buildings; or for
any damage or inconvenience which may arise through repair or alteration of any
part of the Building, Other Buildings or Center, or failure to make any such
repairs, or through operations in the construction of any public or quasi-public
work.

         T. Waiver of Subrogation. Anything in this Lease to the contrary
notwithstanding, Landlord and Tenant each hereby waives any and all rights of
recover, claim, action or cause of action, against the other, its agents,
officers or employees for any loss or damage to or loss of any part of the
Leased Premises or any improvements thereto, or for damage to or loss of any
personal property of such party therein, by reason of fire, the elements, or any
other perils to the extent against which such matters are insured under the
terms of the standard fire and extended coverage insurance policies required
hereunder, regardless of cause or origin, including negligence of the other
party hereto, its agents, officers or employees, and each party hereto covenants
that to the extent permitted by the laws and insurance regulations of the State
of Texas, without penalty or extra premium charge on account thereof, no insurer
shall hold any right of subrogation against such other party, but only to the
extent that such waiver would not have the effect of invalidating any insurance
coverage of Landlord or Tenant.

         U. Landlord's Lien. In consideration of the mutual benefits arising
under this Lease, Tenant hereby grants to Landlord a lien and security interest
in all property of Tenant now or hereafter placed in or on the Leased Premises,
including, but not limited to, all fixtures, equipment, furnishings and other
articles of personal property and such property shall be and remain subject to
such lien and security interest of Landlord for payment of all rent and other
sums agreed to be paid by Tenant herein; provided however, that Landlord hereby
subordinates its lien and security interest to any lien or security interest
which may attached Tenant's personal property in favor of any third party
providing financing to Tenant. Landlord will provide Subordination Agreements
reasonably acceptable to all such third party creditors. Said lien and security
interest shall in addition to and cumulative of Landlord's liens provided by
law. This Lease shall constitute a security agreement under the Texas Uniform
Commercial Code so that Landlord shall have and may enforce said security
interest and Tenant agrees to execute, as debtor, such financing statement or
statements as Landlord, as secured party, may now or hereafter reasonably
request in order that such security interest or interests may be perfected
pursuant to said Code. Landlord may at its election at any time file a copy of
this Lease as a financing statement for this purpose, the addresses given in
Paragraph D of Article VI hereof shall be deemed to be the addresses of Landlord
and Tenant. Landlord, as secured party shall be entitled to all of the rights
and remedies afforded a secured party under the Texas Uniform Commercial Code,
which rights and remedies shall be in addition to and cumulative of the
Landlord's liens and rights provided by law or by the other terms and provisions
of this Lease.

                                   ARTICLE VI

         Landlord and Tenant further covenant and agree as follows:

         A. Successors and Assigns. This Lease shall be binding upon and inure
to the benefit of the successors and assigns of Landlord, and shall be binding
upon and inure to the benefit of Tenant,


                                      -16-
<PAGE>   17
its successors, heirs, executors, administrators or legal representatives, and
to the extent assignment may be approved by Landlord, hereunder, Tenant's
assigns.

         B. Certifications. Landlord and Tenant respectively agree at any time
and from time to time during the Term, upon not less than ten (10) days prior
written request therefor from the other said party, to execute, acknowledge and
deliver unto the requesting party a statement or statements, in writing,
certifying (if such be true) that this Lease is unmodified and in good standing
(or if modified, then in good standing as modified, stating the modification),
and the date or dates, if any, to which Base Rental, additional rent or other
charges hereunder, if any, have been paid in advance, it being the intention of
the parties hereto that any such statement may be relied upon by any prospective
purchaser, mortgagee or assignee of any mortgagee of the Leased Premises, the
Building, Other Buildings, Center or any part thereof, by any other tenant in
the Building or by any approved assignee or subtenant of the Tenant herein.

         C. Memorandum of Lease. Promptly after the commencement date of the
Term, Landlord and Tenant may, in accordance with Paragraph A of Article II,
execute a memorandum or short form of this Lease Agreement, in recordable form,
acknowledging Tenant's acceptance of the Leased Premises for all purposes herein
provided and specifying the commencement date and the termination date of the
Term, and said agreement shall be recorded, at Landlord's option, in the Office
of the County Clerk of Harris County, Texas, but this Lease itself shall not be
recorded.

         D. Notices. All notices required or permitted to be given hereunder by
either party hereto to the other said party, shall be deemed sufficiently given
or made as of the date when mailed by United States Registered Mail, Return
Receipt Requested, adequate postage prepaid, to their respective addresses as
follows:


        Landlord                                      Tenant
--------------------------------------------------------------------------------

Sam H. Hawkins / dba                         Introgen Therapeutics, Inc.
Plaza del Oro Business Center                8080 North Stadium Blvd.
8012 El Rio                                  Suite 1200
Houston, Texas 88054                         Houston, Texas 77054
                                             Attn:  David Enloe

         Either party hereto may, by notice to the other party in the manner
hereinabove provided, change its mailing address.

         E. Payments. No payment made by Tenant or received by Landlord in an
amount less than the monthly installment of Base Rental, any additional rent or
other charges payable by Tenant hereunder shall be deemed to be other than on
account of the earliest stipulated Base Rental, additional rent or other charges
payable by Tenant hereunder, nor shall any endorsement or statement on any check
or any letter accompanying any check or payment as such sum be deemed an accord
and satisfaction, and Landlord may accept any such check or payment without
prejudice to Landlord's


                                      -17-
<PAGE>   18
right to recover the balance of such sum or to pursue any other remedy in this
Lease or by law provided Landlord. All payments due hereunder shall be deemed
made on the date received by Landlord and not on the date mailed.

         F. Entire Agreement. This Lease, together with the Exhibits aforesaid,
and the rider or riders, if any, attached hereto and forming a part hereof,
contain and set forth the entire agreement and understanding between the parties
hereto concerning the Leased Premises, and there are no covenants, promises,
agreements, conditions or understandings either oral or written, between said
parties other than as herein expressly set forth. Except as herein otherwise
provided, no subsequent alteration, amendment, change or addition to this Lease
shall be binding upon either party hereto, unless reduced to writing and signed
by both Landlord and Tenant.

         G. No Partnership. Landlord does not become a partner of Tenant in the
conduct of its business or otherwise, or a joint venturer or a member of a joint
enterprise with Tenant by virtue of this Lease.

         H. Force Majeure. In the event either party hereto shall be delayed,
hindered or prevented from the performance of any act required hereunder by
reason of strike, lockouts, labor disputes, labor troubles, inability to procure
materials, failure of power, restrictive governmental laws or regulations,
riots, insurrection, war or other reason of like nature not the fault of the
party so delayed, then the performance of such acts shall be excused for the
period of the delay and the period for the performance of any such act shall be
extended for a period equivalent to the period of such delay; provided that if
for any reasons set forth in this Article VI (H), Landlord should be unable to
provide peaceful occupancy of the premises together with the services Landlord
is obligated to provide herein, then Tenant shall be excused from paying rent
for so long as such occupancy or services are not available.

         I. Captions. The captions, paragraph numbers and article numbers
appearing in this Lease are inserted only as a matter of convenience and in no
way define, limit, construe or describe the scope or intent of such sections or
articles, nor in anyway affect this Lease.

         J. Pronouns. The word "Tenant" shall be deemed and taken to mean each
and every person or party mentioned as a Tenant herein, be the same one or more;
and if there shall be more than one Tenant any notice required or permitted by
the terms of this Lease may be given by or to any one thereof and shall have the
same force and effect as if given by or to all thereof. The use of the neuter
singular pronoun to refer to Landlord or Tenant shall be deemed a proper
reference even though Landlord or Tenant may be an individual, a partnership, a
corporation, or group of two or more individuals or corporations. The necessary
grammatical changes required to make the provisions of this Lease apply in the
plural sense where there is more than on Landlord or Tenant, and to either
corporations, associations, partnerships or individuals, males or females, shall
in all instances be assumed as though in each case fully expressed.

         K. Brokerage. Each party hereto represents and warrants unto the other
that there are no claims of brokerage commissions or finder's fees in connection
with the negotiation or execution of


                                      -18-
<PAGE>   19
this Lease except that agreement between Tenant and Colliers Appelt Womack dated
the 26th of May, 1996, and each of the parties hereto agrees to indemnify and
save the other harmless from and against all liabilities arising from any other
claim, including without limitation, cost of attorney's fees in connection
therewith.

         L. Severability. If any provision, covenant or condition of this Lease
or the application thereof to any person or circumstance shall, to any extent,
be invalid or unenforceable, the remainder of this Lease, or the application of
such provision, covenant or condition to person or circumstances other than
those as to which it is held invalid or unenforceable, shall not be affected
thereby and each provision, covenant or condition of this Lease shall be valid
and shall be enforced to the fullest extent permitted by law.

         M. Survival. Any representation, warranty, covenant or agreement
contained herein which contemplated performance after the expiration or
termination of this Lease shall be deemed to survive such expiration or
termination.

         N. No Personal Liability. Tenant agrees to look solely to Landlord's
interest in the Development for the recovery of any judgement from Landlord, it
being agreed that Landlord shall never be personally liable for any such
judgement.

         O. Option to Extend. Tenant is hereby granted an option to extend the
term of this lease for a six (6) month period upon the same terms and conditions
as herein contained, provided, Tenant gives Landlord written notice at lease
sixty (60) days prior to the expiration of the initial term of its election to
exercise the option. If the term hereof is so extended then the rental to be
paid for the six (6) month option term shall be an amount equal to the rental
provided to be paid for the initial terms hereunder.

         P. Leasehold Repairs: Landlord agrees to patch existing holes in walls,
touch up paint and replace existing carpet prior to occupancy by Tenant.


                                      -19-
<PAGE>   20
         EXECUTED, as of the day, month and year first hereinabove written.

                                            Sam H. Hawkins, dba
                                            PLAZA DEL ORO BUSINESS CENTER



                                            By:  /s/ SAM H. HAWKINS
                                               -------------------------------
                                                   Landlord


                                            INTROGEN THERAPEUTICS, INC.



                                            By:  /s/ DAVID NANCE
                                               -------------------------------
                                                   Name:  David Nance
                                                   Title:  President


                                      -20-
<PAGE>   21
                                    EXHIBIT A

SURVEY OF 464,366 SQUARE FEET OR 10.6604 ACRES OUT OF UNRESTRICTED RESERVE "A"
OF PLAZA DEL ORO, SECTION 6, AS RECORDED IN VOLUME 264, PAGE 51, HARRIS COUNTY
MAP RECORDS; SAID 10.6604 ACRES BEING PART OF A CERTAIN 6.6135 ACRE TRACT
DESCRIBED IN DEED RECORDED UNDER HARRIS COUNTY CLERK'S FILE NO. H161823, ALL OF
A CERTAIN 2.6474 ACRE TRACT DESCRIBED IN DEED RECORDED UNDER CLERK'S FILE NO.
J157466, AND PART OF A CERTAIN 7.9752 ACRE TRACT DESCRIBED IN DEED RECORDED
UNDER CLARK'S FILE NO. H161825, OFFICIAL PUBLIC RECORDS OF REAL PROPERTY,
LOCATED IN THE P.W. ROSE SURVEY, ABSTRACT NO. 645, HARRIS COUNTY, TEXAS:

BEGINNING at a 5/8 iron rod found for the northwest corner of Unrestricted
Reserve "A" of Plaza Del Oro Section 6 and the southwest corner of Lot 8, Block
42 of Institute Place as recorded in Volume 4, Page 32, Harris County Map
Records, said point being in the east line of a 100 foot wide Houston and Great
Northern Railroad Company easement as described in Volume 10, Page 612, Harris
County Deed Records, and the north line of a 60 foot wide railroad easement as
described in Volume 2646, Page 414, Harris County Deed Records;

THENCE S 72 deg 16 min. 04 sec. E, along a common line, being the south line of
Block 42 and 43 of said Institute Place and the north lines of Unrestricted
Reserve "A" of Plaza Del Oro Section 6 and said 60 foot wide railroad easement,
458.34 feet to a 1/2 inch iron rod set for the northeast corner of the herein
described tract;

THENCE S 17 deg. 43 min. 56 sec. W, 404.82 feet to a 1/2 inch iron rod set in
the north line of El Camino (60 feet wide);

THENCE in a southwesterly direction with the north line of El Rio along a curve
to the left having a radius of 85.00 feet and a central angle of 70 deg. 55 min.
30 sec., for an arc distance of 105.22 feet to a 1/2 inch iron rod set for the
point of tangency;

THENCE S 17 deg. 25 min. 00 sec. W, along the west line of El Rio 612.34 feet to
a 5/8 inch iron rod found for the southeast corner of the herein described
tract;

THENCE N 72 deg. 35 min. 00 sec. W, along the north line of a certain 3.365 acre
tract described in deed dated December 11, 1981 to State Farm Mutual Automobile
Insurance Company recorded under Clerk's File No. H261112, 400.00 feet to a 5/8
inch iron rod found in the common line between the above mentioned Houston and
Great Northern Railroad Company 100 foot wide easement and Unrestricted Reserve
"A" of Plaza Del Oro Section 6 for the southwest corner of the herein described
tract;

THENCE N 17 deg. 25 min. 00 sec. E, along the east line of said 100 foot
railroad easement, 940.53 feet to a 1/2 inch iron rod set for the point of
curvature of a curve to the right;

THENCE in a northeasterly direction with said common line along a curve to the
right having a radius of 11,409.22 feet and a central angle of 0 deg. 48 min. 03
sec., for an arc distance of 159.47 feet to the POINT OF BEGINNING and
containing 464,366 square feet or 10.6604 acres of land.
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                                    EXHIBIT B

                               [PLAN OF PREMISES]
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                                    EXHIBIT C

                               [PLAN OF PREMISES]