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                                                                   EXHIBIT 10.79

                                 LEASE AGREEMENT

THIS LEASE AGREEMENT, made this 20(th) day of November, 1999, by and between
RICKMAN FIRSTFIELD ASSOCIATES ("LANDLORD") and THERIMMUNE RESEARCH CORPORATION
("TENANT').

                              W I T N E S S E T H:

1.       DEMISE OF PREMISES

         Landlord hereby demises unto Tenant, and Tenant hereby leases from
         Landlord for the terms and upon the conditions set forth in this Lease
         30,600 square feet of space in the building located at 15 Firstfield
         Road, Gaithersburg, Maryland "Building'), as set forth on Exhibit A,
         hereto attached, said space being referred to as the "Premises."

2.       TERM

         The term of this Lease shall be for a period of 10 years, commencing on
         the lst day of April, 2000, and terminating on the 31st day of March,
         2010, with an option for an additional 5 years on the same terms and
         conditions in this Lease, provided that Tenant shall have given the
         Landlord written notice of Tenant's intention to do so at least six (6)
         months prior to the expiration of this Lease and that Tenant is not in
         default under this Lease.

         Commencement of the Lease is contingent upon Rickman Firstfield
         Associates and R.O.W. Sciences, Inc. agreeing to the termination of the
         lease dated December 12, 1991, between Rickman Firstfield Associates
         and R.O.W. Sciences, Inc. Should Rickman Firstfield Associates and
         R.O.W. Sciences, Inc. fail to reach an agreement, then this Lease
         between Rickman Firstfield Associates and TherImmune Research
         Corporation is null and void.

3.       RENT

         The Tenant shall pay to the Landlord an annual rental (herein called
         "Minimum Rent") in the amount of FIVE HUNDRED NINETY FIVE THOUSAND
         SEVEN HUNDRED EIGHTY TWO and NO/100 DOLLARS ($595,782.00), subject to
         adjustment as hereinafter set forth, payable without deduction or set
         off in equal monthly installments of FORTY NINE THOUSAND SIX HUNDRED
         FORTY EIGHT and 50/100 DOLLARS ($49,648.50) in advance, the first
         installment of which is due and payable upon signing of the Lease and
         upon commencement all subsequent installments due and payable on the
         first day of each calendar month thereafter during the term of the
         Lease until the total rent provided for herein is paid. No payment by
         Tenant or receipt of Landlord of a lesser amount than a monthly
         installment of rent herein stipulated, or endorsement or statement on
         any check or any letter accompanying any check for payment as rent be
         deemed an accord and satisfaction, and Landlord may accept such check
         for payment without prejudice to Landlord's right to recover the
         balance of such rent or pursue any other remedy provided for in this
         Lease.

4.       ADJUSTMENT OF MINIMUM RENT

         The Minimum Rent shall be increased at the end of each lease year
         during the term hereby by three percent (3%) of the rent then being
         paid. There shall be no additional pass-throughs of increases in
         operating expenses except for real taxes or as otherwise provided for
         herein.

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5.       REAL ESTATE TAXES

         In the event the real estate taxes levied or assessed against the land
         and Building on which the Premises are a part in future tax years are
         greater than the real estate taxes for the Base Year, the Tenant shall
         pay within thirty (30) days after submission of the bill to Tenant for
         the increase in real estate taxes, as additional rent, a proportionate
         share of such increase, which proportionate share shall be computed at
         100% of the increase in taxes, but shall exclude any fine, penalty, or
         interest charge for late or non-payment of taxes by Landlord. The Base
         Year shall be July 1, 1991, to June 30, 1992.

         Any reasonable expense incurred by Landlord (including counsel fees) in
         contesting any tax increase shall be included as an item of taxes for
         the purpose of computing additional rent due Landlord. Landlord,
         however, shall be under no obligation to contest any tax increase.

6.       UTILITIES

         Tenant shall be responsible for the payment of all utilities used or
         consumed by the Tenant in and upon the Premises. Electric, Gas, and
         Water shall be separately metered. In the event any utility service to
         the Premises shall be interrupted for a period of more than two (2)
         days due to the negligence or willful misconduct of Landlord, its
         agents or servants, the Minimum Rent shall abate until such services
         are fully rendered.

         Landlord shall not be liable to Tenant for any damage or inconvenience
         caused by the cessation or interruption of any utility service, or the
         elevators in the Building, occasioned by fire, accident, strike or
         other cause beyond Landlord's control.

7.       USE OF PREMISES

         Tenant shall use the Premises only for laboratory and office purposes,
         and for no other purpose, except as approved by Landlord in advance, in
         writing, which approval shall not be unreasonably withheld. Tenant
         shall not make any use of the Premises which would disturb the quiet
         enjoyment of the Landlord or other tenants in the Building or prejudice
         or increase the fire insurance premium for the Building, and shall
         comply with all laws and regulations of all governmental authorities
         pertaining to Tenant's use of Premises.

8.       WASTE REMOVAL

         Tenant shall be responsible for removal of waste generated by Tenant's
         operation. This includes waste service fees levied by local
         jurisdictions.

9.       HAZARDOUS MATERIALS

         Tenant shall be permitted to store Hazardous Materials on the Premises
         and shall comply with all laws and regulations of all governmental
         authorities pertaining to Tenant's use of the Premises, including,
         without limitation, all Environmental Laws (as hereinafter defined) and
         laws pertaining to Hazardous Materials and Air and Water Quality. The
         term "Hazardous Materials" means and includes any petroleum products
         and/or any hazardous toxic or other dangerous waste, substance or
         material defined as such in the Environmental Laws. The term
         "Environmental Laws" means the Comprehensive Environmental Response,
         Compensation and Liability Act, any "Superfund" or "Superlien" law, or
         any other federal, state or local statute, law, ordinance, code,
         regulation, order or decree regulating, relating to, or imposing
         liability or standards of conduct concerning the use or storage of
         Hazardous Materials. All such materials must be completely removed upon
         expiration of this Lease, and any de-contamination

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         certificates required by the Landlord or any government authority must
         be obtained and delivered to the Landlord.

         Tenant shall obtain and maintain, in full force and effect, all
         necessary government licenses, permits and approvals legally required
         for materials used in the conduct of its business. If the presence of
         any Hazardous Materials on the Premises caused or permitted by Tenant
         results in any contamination of the Premises or any portion of the
         Building or Common Areas, Tenant shall promptly take all actions, at
         its sole expense, necessary to return the Premises to the condition
         existing prior to the introduction of such Hazardous Materials,
         provided that all such actions shall be subject to the approval of
         Landlord, which approval shall not be unreasonably withheld.

         At the Commencement Date of the Lease and on January 1 of each year
         thereafter, Tenant shall disclose to Landlord the names and amounts of
         all Hazardous Materials which are to be stored, used or disposed of on
         the Premises.

         Any Hazardous Materials stored or used on the Premises must not in any
         way prejudice the Landlord's insurance or increase the fire hazards to
         a greater extent than necessarily incident to the business for which
         the Premises are leased.

10.      LATE CHARGE

         If any installment of rent accruing hereunder or any other sums payable
         hereunder shall not be paid within fifteen (15) days after written
         notice to Tenant, such installment and other sums shall he increased
         without affecting Landlord's other rights under this Lease, by a late
         charge of five percent (5%) of the delinquent installment. Anything
         contained herein to the contrary notwithstanding.

11.      REPAIRS AND MAINTENANCE

         Landlord shall be responsible for all structural repairs, including
         repairs to the roof and load-bearing walls of the Building, for
         maintaining the parking area and sidewalks, including snow and ice
         removal. The Tenant shall be responsible for the maintenance and repair
         of the Premises and all fixtures, appliance, and equipment therein,
         including, but not limited to, the Heating and Conditioning system.
         Landlord will pay for major Heating and Air Conditioning component
         replacement and all repairs to the heating and air conditioning system
         in excess of Two Hundred Fifty Dollars ($250.00) per unit per
         occurrence. Tenant shall provide its own char service. Landlord will
         repair and replace any glass breakage, provided it is not the result of
         the Tenant's willful or negligent act. Tenant, at its sole expense,
         shall keep all Tenant fixtures and equipment in the Premises in safe
         and sanitary condition and good order and repair, together with related
         plumbing, electrical or other utility service, whether installed by
         Tenant or by Landlord on Tenant's behalf. Tenant shall pay for all
         damage to the Building and any fixtures and appurtenances related
         thereto due to the malfunction, lack of repair, or improper
         installation of the Tenant's fixtures and equipment.

12.      LANDLORD'S WORK PRIOR TO COMMENCEMENT OF TERM

         Landlord shall make the following improvements to the lower level of
         the Premises prior to the commencement of the term of the Lease:

         Construction in accordance with Exhibit A.

13.      TENANT ALTERATIONS

         All alterations, improvements, or additions to the demised Premises to
         be made by Tenant shall be subject to the written consent of the
         Landlord, which consent shall not be unreasonably withheld, provided
         such alterations and improvements do not weaken the

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         structural integrity of the Building or detract from its dignity and/or
         uniformity. All alterations and improvements and/or additions made by
         Tenant shall remain upon the

         Premises at the expiration or earlier termination of this Lease and
         shall become the property of the Landlord, unless Landlord shall, at
         the time of approval of the alteration, provide written notice to
         Tenant to remove the same, in which event Tenant shall remove such
         alterations, improvements and/or additions, and restore the Premises to
         the same order and condition in which it was at the commencement of
         this Lease, reasonable wear and tear and unavoidable casualty excepted.
         Should Tenant fail to do so, Landlord may do so, collecting the
         reasonable cost and expense thereof from Tenant as additional rent.

14.      TRADE FIXTURES

         All trade fixtures, telephone equipment, and apparatus installed by
         Tenant in the Premises shall remain the property of Tenant and shall be
         removed at the expiration or earlier termination of this Lease and,
         upon such removal, Tenant shall repair any damage caused by the removal
         and shall promptly restore the Premises to their good order and
         condition. Any such trade fixture not removed prior to such termination
         shall be considered abandoned property, but such abandonment shall not
         release Tenant of its obligation to pay for the cost of removing such
         trade fixtures and repairing any damage caused by the removal.

15.      QUIET ENJOYMENT

         Landlord covenants that, upon payment of the rent herein provided and
         performance by the Tenant of all other covenants herein contained,
         Tenant shall and may peaceably and quietly have, hold and enjoy the
         Premises for the term hereof and options.

16.      SURRENDER OF PREMISES

         Upon the expiration or termination of this Lease, Tenant shall quit and
         surrender the Premises to the Landlord broom clean and shall remove all
         of its property therefrom. If the removal of any such property shall
         result in damaging the premises, or leaving any holes in the floors,
         walls or ceiling therein, the Tenant shall make the appropriate repairs
         with Landlord approved building materials prior to the expiration of
         this lease. The obligation of this paragraph shall survive the
         termination of the Lease.

17.      INSURANCE

         Tenant covenants and agrees to maintain and carry, at all times during
         the term of this Lease, in companies qualified and authorized to
         transact business in the State of Maryland, general liability insurance
         in amounts of $500,000 per person, $1,000,000.00 per occurrence and
         $100,000.00 for damage to property on the Premises or arising out of
         the use thereof by Tenant or its agents. All policies of insurance
         shall provide that they may not he canceled, except on thirty (30) days
         written notice to Landlord, and all such policies shall name Landlord
         as an additional insured.

         Prior to commencement, Tenant shall furnish Landlord with satisfactory
         proof that the insurance herein provided for is at all times in full
         force and effect. If either party hereto is paid any proceeds under any
         policy of insurance naming such party as an insured on account of any
         loss, damage or liability, then such party hereby releases the other
         party to (and only to) the extent of the amount of such proceeds, from
         any and all liability for such loss or damage, notwithstanding
         negligent or intentionally tortuous act or omission of the other party,
         its agents or employees; provided, such release shall be effective only
         as to a loss of damage occurring while the appropriate policy of
         insurance of the releasing party provides that such release shall not
         impair the effectiveness of such policy or the insured's ability to
         recover thereunder. Each party hereto shall use reasonable efforts to

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         have a clause to such effect included in its said policies, and shall
         promptly notify the other in writing if such clause cannot be included
         in any such policy.

18.      INDEMNIFICATION

         Tenant shall indemnify and hold harmless the Landlord from, and name
         LANDLORD as additional insured on policy regarding, any and all
         liability, damage, expense, cause of action, or claims arising out of
         injury to persons or to property on the Premises, except for the
         negligence or willful misconduct of Landlord, its agents, employees, or
         servants.

19.      DAMAGE BY FIRE OR CASUALTY

         (a)      If the Premises are damaged by fire or other casualty, but are
                  not thereby rendered untenantable in whole or in part,
                  Landlord, at its own expense, and subject to the limitations
                  set forth in this Lease, shall cause such damage to be
                  repaired and the Minimum Rent and Additional Rent shall not be
                  abated.

                  If, by reason of any damage or destruction, the Premises shall
                  be rendered untenantable in whole or in part and cannot be
                  repaired and made tenantable within sixty (60) days after such
                  damage: (i) Landlord, at its option and its own expense, may
                  cause the damage to be repaired and the Minimum Rent and
                  Additional Rent shall be abated proportionately as to the
                  portion of the Premises rendered untenantable while it is
                  untenantable; or (ii) Landlord shall have the right, to be
                  exercised by notice in writing delivered to Tenant within
                  thirty (30) days of the occurrence of such damage or
                  destruction, to terminate this Lease, whereupon the Minimum
                  Rent and Additional Rent shall be adjusted as of the date of
                  such termination.

         (b)      In the event that twenty-five percent (25%) or more of the
                  rentable floor area of the Building shall be damaged or
                  destroyed by fire or other cause, notwithstanding that the
                  Premises may be unaffected by such fire or other damage,
                  Landlord shall have the right, to be exercised by notice in
                  writing delivered to Tenant within thirty (30) days after such
                  occurrence, to terminate this Lease. Upon the giving of such
                  notice, the Minimum Rent and Additional Rent shall be adjusted
                  as of the date of termination and this Lease shall thereupon
                  terminate.

20.      ASSIGNMENT OR SUBLETTING

         Tenant acknowledges that Landlord has entered into this Lease because
         of Tenant's financial strength, goodwill, ability and expertise and
         that accordingly, this lease is personal to Tenant. Taking this into
         consideration, tenant shall not assign, mortgage, sublet, pledge or
         encumber this Lease, in whole or in part, except with the written
         consent of the Landlord, which shall not be unreasonably withheld or
         delayed. Tenant agrees that, in the event of any such assignment or
         subletting, Tenant shall nevertheless remain liable for the performance
         of all terms, covenants, and conditions of this Lease.

21.      SUBORDINATION AND ATTORNMENT

         This Lease shall be subject to and subordinate at all times to the lien
         of any mortgage and/or deeds of trust and all land leases now or
         hereafter made on any portion of the Premises, and to all advances
         thereunder, provided the mortgagee or trustee named in said mortgage or
         deed of trust shall agree to recognize this Lease and agrees, in the
         event of foreclosure, not to disturb the Tenant's possession hereunder,
         provided Tenant is not in default under this Lease. This subordination
         shall be self-operative and no further instrument of subordination
         shall be required.

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         If any proceedings are commenced to foreclose any mortgage or deed of
         trust encumbering the Premises, Tenant agrees to attorn to the
         purchaser at the foreclosure sale, if requested to do so by any such
         purchaser, and to recognize such purchaser as the Landlord under this
         Lease, provided purchaser shall agree that Tenant's rights hereunder
         shall not he disturbed so long as Tenant has not committed any event of
         default as to which the applicable cure period has not expired.

22.      CONDEMNATION

         (a)      If the whole of the Premises shall be taken by any public or
                  quasi-public authority under the power of eminent domain,
                  condemnation or conveyance in lieu thereof, then this Lease
                  shall terminate as of the date on which possession of the
                  Premises is required to be surrendered to the condemning
                  authority and the Tenant shall have no claim against Landlord
                  or the condemning authority for the value of the unexpired
                  term of this Lease. Tenant shall have the right to claim,
                  however, the unamortized cost of any improvements or additions
                  made to the Premises by Tenant at its cost, the value of any
                  Tenant fixtures and furnishings and any moving expenses.

         (b)      If a portion of the Premises shall be so taken or conveyed,
                  and if such partial taking or conveyance shall render the
                  Premises unsuitable for the business of the Tenant, then the
                  term of this Lease shall cease and terminate as of the date on
                  which possession of the portion of the Premises is surrendered
                  to the condemning authority, and Tenant shall have no claim
                  against Landlord or the condemning authority for the value of
                  any unexpired term of this Lease.

                  In the event such partial taking or conveyance is not
                  extensive enough to render the Premises untenantable for the
                  business of Tenant, this Lease shall continue in full force
                  and effect, except that the Minimum Rent shall be reduced in
                  the same proportion that the floor area of the Premises so
                  taken or conveyed bears to such floor area immediately prior
                  to taking or conveyance.

                  In the event of such partial taking and continuation of Lease,
                  Landlord shall promptly restore the Premises as nearly as
                  practical to the condition comparable to that which existed
                  prior to the condemnation.

23.      EVENTS OF DEFAULT

         The occurrence of any of the following shall constitute an event of
         default hereunder:

         (a)      Failure of Tenant to pay installment of rent hereunder within
                  ten (10) days of the due date, or failure of Tenant to pay
                  within twenty (20) days after receipt of written notice any
                  other sum herein required to be paid by Tenant.

         (b)      Tenant's failure to perform any other covenant or condition of
                  this Lease within thirty (30) days after receipt of written
                  notice and demand, unless the failure is of such a character
                  as to require more than thirty (30) days to cure in which
                  event Tenant's failure to proceed diligently to cure such
                  failure shall constitute an event of default.

24.      LANDLORD'S REMEDIES

         Upon the occurrence of any event of default, Landlord may, at
         Landlord's sole option, exercise any or all of the following remedies,
         together with any such other remedies as may be available to Landlord
         at law or in equity.

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         (a)      Landlord may terminate this Lease by giving Tenant written
                  notice of its election to do so, as of a specified date not
                  less than thirty (30) days after the date of the giving of
                  such notice and this Lease shall then expire on the date so
                  specified, and Landlord shall then be entitled to immediately
                  regain possession of the Premises as if the date had been
                  originally fixed as the expiration date of the term of this
                  Lease. Landlord may then re-enter upon the Premises, either
                  with or without due process of law, and remove all persons
                  therefrom, the statutory notice to quit or any other notice to
                  quit being hereby expressly waived by Tenant. Tenant expressly
                  agrees that the exercise by Landlord of the right of re-entry
                  shall not be a bar to or prejudice in any way other legal
                  remedies available to Landlord. In that event, Landlord shall
                  he entitled to recover from Tenant as and for liquidated
                  damages an amount equal to the rent and additional rent
                  reserved in this Lease less any and all amounts received by
                  Landlord from the rental of the Premises to another tenant.
                  Nothing herein contained, however, shall limit or prejudice
                  the right of Landlord to prove for and obtain as liquidated
                  damages, by reason of such termination, an amount equal to the
                  maximum allowed by any statute or rule of law in effect at the
                  time when, and governing the proceedings in which such damages
                  are to be proved, whether or not such amount may be greater,
                  equal to, or less than the amount of the difference referred
                  to above, and the Landlord may, in his own name, but as agent
                  for Tenant, re-let the Premises. Any recovery by the Landlord
                  shall be limited to the rent hereunder (plus any costs
                  incurred in re-letting) less any rent actually paid by the new
                  tenant.

         (b)      No termination of this Lease or any taking of possession of
                  the Premises shall deprive Landlord of any of its remedies or
                  actions against Tenant for past or future rent, nor shall the
                  bringing of any action for rent or breach of covenant, or the
                  resort to any other remedy herein provided for the recovery of
                  rent, be construed as a waiver of the right to obtain
                  possession of the Premises.

         (c)      In addition to any damages becoming due under this paragraph,
                  Landlord shall be entitled to recover from Tenant and Tenant
                  shall pay to Landlord an amount equal to all expenses,
                  including attorneys' fees, if any, incurred by the Landlord in
                  recovering possession of the Premises, and all reasonable
                  costs and charges for the care of said Premises while vacant,
                  which damages shall be due and payable by Tenant to Landlord
                  at such time or times as such expenses are incurred by the
                  Landlord.

         (d)      In the event of a default or threatened default by Tenant of
                  any of the terms or conditions of this Lease, Landlord shall
                  have the right of injunction and the right to invoke any
                  remedy allowed by law or in equity as if no specific remedies
                  of Landlord were set forth in this Lease.

         (e)      If default be made and a compromise and settlement shall be
                  had thereupon, it shall not constitute a waiver of any
                  covenant herein contained, nor of the Lease itself.

25.      RIGHTS OF LANDLORD

         Landlord reserves the following rights with respect to the Premises:

         (a)      During normal business hours, upon 24 hours notice, to go upon
                  and inspect the Premises, and at Landlord's option, to make
                  repairs, alterations and additions to the Premises or the
                  Building of which the Premises are a part, provided there is
                  no interference with Tenant's occupancy. An Agent of the
                  Tenant may be present for inspection, if requested by Tenant.

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         (b)      To display, within sixty (60) days prior to the expiration of
                  this Lease or after notice from either party of intention to
                  terminate this Lease, a "For Rent" sign, and all of said signs
                  which shall be placed upon such part of the Premises as
                  Landlord shall determine, except on doors leading into the
                  Premises. Prospective purchasers or tenants authorized by
                  Landlord may inspect the Premises during normal business hours
                  following adequate notice to Tenant.

         (c)      To install, place upon, or fix to the roof and exterior walls
                  of the Premises, equipment, signs, displays, antennae, and any
                  other object or structure of any kind, providing the same
                  shall not materially impair the structural integrity of the
                  Building or interfere with Tenant's occupancy.

26.      HOLDING OVER

         It Tenant holds possession of the Premises after the termination of
         this Lease or any renewal or extension thereof, Tenant shall become a
         Tenant from month to month at 125% of the then current escalated rental
         rate.

27.      WAIVER OF CLAIMS

         Except as may result from their negligence, Landlord and Landlord's
         agents, employees, and contractors shall not be liable for, and Tenant
         hereby releases all claims for, damages to persons or property
         sustained by Tenant (or any person claiming through Tenant) resulting
         from any fire, accident, occurrence or condition in or upon the
         Premises or Building, including but not limited to such claims for
         damage resulting from (1) any defect in or failure of plumbing, heating
         or air-conditioning equipment, electric wiring or installation thereof,
         water pipes, stairs, railings or walks; (2) any equipment or apparatus
         becoming out of repair (3) the bursting, leaking or running of any
         tank, washstand, water closet, waste pipe, drain or any other pipe or
         tank, upon or about such building or premises; (4) the backing up of
         any sewer pipe or downspout; (5) the escape of steam hot water; (6)
         water, snow or ice being upon or coming through the roof of any place
         upon or near the Building or Premises or otherwise; (7) the falling of
         any fixtures, plaster or stucco; (8) broken glass; and (9) any act or
         omission of occupants of adjoining or contiguous property of buildings.

28.      NOTICE

         All notices required under this Lease shall be given in writing and
         shall be deemed to be properly serviced if sent by certified or
         registered United States Mail, postage prepaid, as follows:

           If to the Landlord:              W. M. Rickman Construction Co.

                                            15215 Shady Grove Road

                                            Suite 201

                                            Rockville, Maryland 20850

           If to the Tenant:                TherImmune Research Corporation

                                            555 Quince Orchard Road

                                            Suite 460

                                            Gaithersburg, Maryland 20878

                                            Attention: Stephen J. Trevisan

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         or to such other address as either may have designated from time to
         time by written notice to the other. The date of service of such
         notices shall be the date such notices are deposited in any United
         States Post Office.

29.      COVENANTS OF TENANT

         Tenant covenants and agrees:

         (a)      To give to Landlord prompt written notice of any accident,
                  fire, or damage occurring on or to the Premises.

         (b)      To keep the thermostats in the Premises set at a temperature
                  sufficient to prevent freezing of water pipes, fixtures and
                  HVAC units.

         (c)      To keep the Premises clean, orderly, sanitary, and free from
                  all objectionable odors and from insects, vermin and other
                  pests.

         (d)      To comply with the requirements of the State, Federal and
                  County statutes, ordinances, and regulations applicable to
                  Tenant and its use of the Premises, and to save Landlord
                  harmless from penalties, fines, costs, and expenses resulting
                  from failure to do so, provided Tenant shall not be obligated
                  to make structural repairs or alterations to so comply.

         (e)      Tenant shall promptly pay all contractors, suppliers of
                  material and persons it engages to perform work and provide
                  materials for construction work on the Premises so as to
                  minimize the possibility of a lien attaching to the Premises.
                  Should any such lien be made or filed, Tenant shall cause the
                  same to be discharged and released of record by bond or
                  otherwise within ten (10) days of receipt of written request
                  from Landlord.

30.      LANDLORD'S RIGHT TO ALTER SITE PLAN

LANDLORD shall, from time to time, have the right to alter or modify the site
plan of the Building and to rearrange the driveways and parking areas, as well
as the entrance and exits to the Premises.

31.      PARKING SPACES

         LANDLORD agrees to furnish 3 1/3 unreserved parking spaces per thousand
         square feet of space occupied by the TENANT.

32.      ENTIRE AGREEMENT

         This Lease contains the entire agreement of the parties. There are no
         oral agreements existing between them.

33.      SUCCESSORS AND ASSIGNS

         This Lease, and the covenants and conditions herein contained shall
         inure to the benefit of and be binding upon the Landlord, its
         successors and assigns, and shall inure to the benefit of and be
         binding upon the Tenant, its successors and assigns, if permitted.

34.      BANKRUPTCY

         If Tenant shall make an assignment of its assets for the benefit of
         creditors, or if Tenant shall file a voluntary petition in bankruptcy,
         or if any involuntary petition in bankruptcy or for receivership be
         instituted against the Tenant and the same be not dismissed within
         thirty (30) days of the filing thereof, or if Tenant shall be adjudged
         bankrupt, then and in any of said events, this Lease shall immediately
         cease and terminate at the option of the Landlord with the same force
         and effect as though the date of said event was the date herein fixed
         for expiration of the term of this Lease.

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35.      NON-DELIVERY

         In the event the Landlord shall be unable to give possession of the
         Premises because construction of the Building is not complete or for
         any other cause reasonably beyond the control of the Landlord, the
         Landlord shall not be liable to Tenant for any damage resulting from
         failure to give possession.

36.      PARTIAL INVALIDITY

         If any term, covenant, or condition of this Lease or the application
         thereof to any person or circumstance shall be held to be invalid and
         unenforceable, the remainder of this Lease, and the application of such
         terms, covenants, or conditions shall be valid and enforceable to the
         fullest extent permitted by law.

37.      FORCE MAJEUR

         With the exception of those provisions contained herein regarding the
         payment of rent, the inability of either party to perform any of the
         terms, covenants or conditions of this Lease shall not be deemed a
         default if the same shall be due to any cause beyond the control of
         that party.

38.      ESTOPPEL CERTIFICATE

         The Tenant shall from time to time, within five (5) days after being
         requested to do so by the Landlord or any Mortgagee, execute,
         acknowledge and deliver to the Landlord (or, at the Landlord's request,
         to any existing or prospective purchaser, transferee, assignee or
         Mortgagee of any or all of the Premises) an instrument in recordable
         form, certifying (a) that this Lease is unmodified and in full force
         and effect (or, if there has been any modification thereof, that it is
         in full force and effect as so modified, stating therein the nature of
         such modification); (b) as to the dates to which the Minimum Rent and
         other charges arising hereunder have been paid; (c) as to the amount of
         any prepaid Rent or any credit due to the Tenant hereunder; (d) that
         the Tenant has accepted possession of the Premises, and the date on
         which the Term commenced; (e) as to whether, to the best knowledge,
         information and belief of the signer of such certificate, the Landlord
         or the Tenant is then in default in performing any of its obligations
         hereunder (and, if so, specifying the nature of each such default); and
         (f) as to any other fact or condition reasonably requested by the
         Landlord or such addressee. In the event the Tenant fails or refuses to
         provide such a certificate, Tenant shall be liable to Landlord for any
         loss or damage (including reasonable counsel fees) arising out of or in
         connection with such failure or refusal.

<PAGE>

IN WITNESS WHEREOF, the parties have caused this Lease Agreement to he executed
on the year and date first written.

WITNESS:                                LANDLORD:

                                        RICKMAN FIRSTFIELD ASSOCIATES

/s/ Ross L. Englehart                    /s/ William M. Rickman
--------------------------------       ------------------------------
                                   By:    William M. Rickman
                                       ___________________________________

WITNESS:                                TENANT:

                                        THERIMMUNE RESEARCH CORPORATION

/s/ Nanette Marakovitz                   /s/ Joseph W. Angle, Jr.
--------------------------------       ------------------------------

                                   By:   Joseph W. Angle, Jr.
                                       ------------------------------