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                                                                    EXHIBIT 4.19

                               COMMERCIAL SUBLEASE

      THIS COMMERCIAL SUBLEASE (the "Sublease") is made this 6th day of April,
2005 (the "Commencement Date"), by and between Exergen Corporation, a
Massachusetts corporation having an address at 400 Pleasant Street, Watertown,
Massachusetts (the "Landlord"), and Control Delivery Systems, Inc., a Delaware
corporation, having its principal place of business at 400 Pleasant Street,
Watertown, Massachusetts (the "Subtenant").

                                   WITNESSETH:

      WHEREAS, by Commercial Building Lease dated as of the date hereof between
FHP, LLC, a Massachusetts limited liability company, as lessor (the
"Overlandlord"), and Landlord as lessee thereunder (the "Original Sublease"),
Overlandlord leased to Landlord the premises, together with the right to use all
sidewalks, parking areas, easements, rights of way and other means of access to
and from public ways and adjoining properties, being the entire premises now
known and numbered as 396-400 Pleasant Street, Watertown, Massachusetts (the
"Property"); and

      WHEREAS, Subtenant desires to sublease from Landlord and Landlord desires
to sublease to Subtenant, a portion of the Premises as shown on Exhibit A
attached hereto and described below on the terms and conditions set forth
herein.

      NOW, THEREFORE, in consideration of the mutual covenants contained herein,
and for other good and valuable consideration, the receipt and sufficiency of
which are hereby acknowledged, the parties hereby agree as follows:

                                    ARTICLE I

                                     DEMISE

      Section 1. Landlord hereby leases the space shown on Exhibit A attached
hereto consisting of 13,411 square feet exclusive use space (the "Subleased
Premises"), together with the right to use in common with others entitled
thereto the approximately 1,038 square feet of common area space shown on
Exhibit A (the "Common Area") and other common walkways, hallways, driveways and
similar areas necessary for access to the Subleased Premises, situated in or
about the building (the "Building") located at the Property to Subtenant and
Subtenant hereby leases and takes the Subleased Premises from Landlord upon the
terms, provisions and conditions in this Sublease contained, and subject to any
easements, restrictions and conditions of record and all laws and ordinances
applicable to the Subleased Premises.

      Section 2. Subtenant acknowledges that Subtenant owned and occupied the
Building prior to the sale of the Building to Landlord by Subtenant on the date
hereof. As a result, Subtenant is thoroughly familiar with the condition of the
Building and agrees that it is leasing the Subleased Premises "as is" with no
representations or warranties by Landlord, including,

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without limitation, any representations or warranties as to habitability or
fitness for a particular purpose.

                                   ARTICLE II

                                      TERM

      Section 1. The term of this Sublease shall commence on the Commencement
Date and shall continue for a period of eighteen (18) months, unless sooner
terminated or extended as herein provided (the "Term").

      Section 2. Landlord and Subtenant each shall have an option to extend the
Term for eighteen (18) months (the "Extension Period"), provided that the party
seeking to exercise such option shall not be in default under any of the
material terms of this Sublease at the time of the exercise. If either Landlord
or Subtenant elects to exercise this option, it shall do so by giving written
notice of such election to the other no later than six (6) months prior to the
end of the original Term. The Extension Period shall be upon the same terms and
conditions of this Sublease, except that during the Extension Period, Subtenant
shall pay Annual Base Rent equal to $23.00 per square foot for the Subleased
Premises and for Subtenant's Proportionate Share (as defined in Article III,
Section 3 below) of the Common Area.

                                   ARTICLE III

                                      RENT

      Section 1. Subtenant shall pay without demand, setoff or deduction as rent
at such place as Landlord from time to time may direct, annual base rent (the
"Annual Base Rent") equal to $22.00 per square foot for the Subleased Premises
and for Subtenant's Proportionate Share (as defined in Article III, Section 3
below) of the Common Area. As of the Commencement Date, the Subleased Premises
constitute 13,411 square feet and Subtenant's Proportionate Share of the Common
Area constitutes 386 square feet. Therefore, Subtenant shall pay as Annual Base
Rent the amount of Three Hundred Three Thousand Five Hundred Thirty Four Dollars
($303,534) in equal monthly installments of Twenty Five Thousand Two Hundred
Ninety Four Dollars ($25,294) on the first day of each calendar month; provided,
however, that the first calendar month's rent shall be paid on the Commencement
Date. If the Commencement Date falls on other than the first day of a calendar
month or if the Term ends on other than the last day of a calendar month, the
Annual Base Rent shall be prorated for the month in which the Term commences or
ends, as the case may be.

      Section 2. During the Term, in addition to Annual Base Rent, Subtenant
agrees to pay to Landlord, as additional rent (the "Additional Rent"),
Subtenant's Proportionate Share (as defined in Article III, Section 3 below) of
all Taxes (as defined in Article III, Section 4 below) and Operating Expenses
(as defined in Article III, Section 5 below) that accrue during the Term and
Subtenant's portion of Shared Utilities (as described in Article V, Sections 2
and 3 below) that accrue during the Term. On the Commencement Date and thirty
(30) days prior to the beginning


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of each calendar year during the Term (including, if applicable, the Extension
Period), Landlord shall submit an estimate of the Additional Rent for the
ensuing calendar year and Subtenant shall pay Landlord such estimated amount of
Additional Rent in monthly installments on the first day of each calendar month
during the Term. At the end of each calendar year during the Term (including, if
applicable, the Extension Period) and at the termination of the Sublease, as
soon as Landlord can determine the actual amount of Additional Rent owed by
Subtenant for the preceding year (or, if applicable, portion thereof), Landlord
shall give Subtenant written notice of such amount (the "Additional Rent
Statement"). The Additional Rent Statement shall include an itemized statement
showing in reasonable detail the actual Taxes, Operating Expenses, and Shared
Utilities for the relevant period broken down by component expenses. Upon
request by Subtenant, Landlord also shall provide appropriate supporting
documentation.

If the actual amount of Additional Rent owed by Subtenant exceeds the estimated
amount paid by Subtenant, Subtenant shall pay such excess to Landlord within ten
(10) days of receipt by Subtenant of the Additional Rent Statement or the end of
the Dispute Period (as defined below). If the estimated amount of Additional
Rent paid by Subtenant exceeded the actual amount owed by Subtenant, Landlord
shall pay such excess to Subtenant within ten (10) days of receipt by Subtenant
of the Additional Rent Statement.

If Subtenant disputes the accuracy of the Additional Rent Statement, Subtenant
shall have thirty (30) days after receiving the Additional Rent Statement, or
such longer time as may be necessary, to audit Landlord's books and records
concerning the Additional Rent Statement at a mutually convenient time at
Landlord's offices. The books and records shall be kept in accord with generally
accepted accounting principles consistently applied. If the parties cannot
resolve the dispute within thirty (30) days after completion of the audit (the
"Dispute Period"), Subtenant shall still pay the amount shown owing within ten
(10) days of the end of the Dispute Period and Subtenant, in its sole
discretion, may commence alternative dispute resolution procedures or submit the
matter to a court of competent jurisdiction. Any such audit shall be conducted
at Subtenant's sole cost and expense. If a court, arbitrator or mediator
determines that the Additional Rent Statement overstated the Additional Rent by
three percent (3%) or more, Subtenant may recover the amount it spent on the
audit, the amount it paid in excess of the correct Additional Rent, and its
reasonable attorneys' fees and costs associated with the dispute. If a court,
arbitrator or mediator determines that the Additional Rent Statement overstated
the Additional Rent, but by an amount less than three percent (3%), then
Subtenant may recover only the amount it paid in excess of the correct
Additional Rent. If Subtenant does not commence alternative dispute resolution
procedures or submit the matter to a court of competent jurisdiction within
sixty (60) days after the end of the Dispute Period, then the Additional Rent
Statement shall be conclusive and final.

The provisions of this Article III, Section 2 shall survive expiration or
termination of the Sublease.


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      Section 3. For all purposes of this Sublease, "Subtenant's Proportionate
Share" of the Building on and as of the Commencement Date shall be 37.19%.
Subtenant's Proportionate Share is calculated as follows:

                          sq. ft. of Subleased Premises

                           --------------------------

                 (sq. ft. of Building - sq. ft. of Common Area)

In the event that the square footage of any pertinent area changes for any
reason, Subtenant's Proportionate Share shall be automatically recalculated in
accordance with the above equation and using the same measurement techniques and
standards originally employed.

      Section 4. "Taxes" shall mean any and all governmental impositions and
taxes imposed upon the Building and/or the Property, including any fire service
or other charges for municipal services, and all betterment assessments, as well
as all ad valorem, license or other taxes imposed upon the Building and/or the
Property and/or imposed upon Landlord by reason of its ownership thereof or this
Sublease; provided, however, that "Taxes" shall not include (i) federal, state,
or local income taxes, (ii) franchise, gift, transfer, excise, capital stock,
estate, succession, or inheritance taxes, (iii) penalties or interest for late
payment of Taxes, or (iv) the portion of Taxes that is allocable to any capital
improvements made after the Commencement Date expect to the extent the
improvements benefit all tenants or at least benefit Subtenant. If at any time
during the Term the methods of taxation of real estate prevailing on the
Commencement Date shall be altered so that in lieu of, in addition to, or as a
substitute for, the whole or any part of the Taxes, there shall be levied,
assessed or imposed (x) a tax, assessment, levy, imposition or charge, wholly or
partially as capital levy or otherwise, on the rents received therefrom, (y) a
tax, assessment, levy, imposition or charge measured by or based in whole or in
part upon the Subleased Premises and imposed upon Landlord, or (z) a tax license
fee or the like measured by the rents payable from Subtenant to Landlord, then
all such taxes, assessments, levies, impositions, or charges, or the part
thereof so measured or based, shall be deemed to be included within the term
"Taxes" for the purposes hereof. In the event of a betterment assessment,
Landlord shall pay in accordance with the longest payment option offered

      Section 5. "Operating Expenses" shall mean any expenses, costs and
disbursements invoiced to Landlord by an unaffiliated entity (except as agreed
to by Subtenant) in connection with the maintenance, operation and repair of all
or any part of the Building, including the Common Area and the parking and other
common areas outside the Building on the Property (in connection with which
Operating Expenses shall include snow removal and landscaping). Landlord agrees
to maintain, operate and repair the Building and Property to a standard
consistent with Subtenant's former ownership thereof. "Operating Expenses" shall
not include (i) costs incurred due to maintenance, operation and repair of the
Building and/or Property to a standard in excess of Subtenant's former ownership
thereof, (ii) expenses, costs, and disbursements incurred in connection with
Shared Utilities (as defined in Article V, Section 2 below), (iii) Taxes (as
defined in Article III, Section 4 above), (iv) leasing commissions, costs,


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disbursements, and other expenses incurred for leasing, renovating, or improving
space for Landlord or other tenants, (v) costs incurred by Landlord in
discharging its obligations under Article XXV, (vi) costs (including permit,
license, and inspection fees) incurred in renovating, improving, decorating,
painting, or redecorating vacant space or space for Landlord or other tenants,
(vii) costs incurred by Landlord for alterations that are considered capital
improvements and replacements under generally accepted accounting principles
consistently applied, (viii) depreciation and amortization on the Building
except as expressly permitted elsewhere in the Sublease, (ix) costs of a capital
nature including capital improvements, capital repairs, capital equipment, and
capital tools, as determined under generally accepted accounting principles
consistently applied, (x) costs incurred because Landlord or another tenant
violated the terms of any lease, (xi) interest on debt or amortization payments
on mortgages or deeds of trust or any other debt for borrowed money, (xii)
rentals and other related expenses incurred in leasing air conditioning systems
or other equipment ordinarily considered to be of a capital nature, but normal
maintenance shall be included, (xiii) items and services for which Subtenant
reimburses Landlord or pays third parties or that Landlord provides selectively
to one or more tenants of the Building other than Subtenant without
reimbursement, (xiv) advertising and promotional expenditures, (xv) repairs or
other work needed because of fire, windstorm, or other casualty or cause insured
against by Landlord or to the extent Landlord's insurance required under this
Sublease would have provided insurance, whichever is the greater coverage, (xvi)
nonrecurring costs incurred to remedy structural defects in original
construction materials or installations, (xvii) any costs, fines, or penalties
incurred because Landlord violated any governmental rule or authority, (xviii)
costs incurred to test, survey, cleanup, contain, abate, remove, or otherwise
remedy Hazardous Material (as defined in Article X, Section 2 below) in, on, or
under the Property unless and to the extent that the Hazardous Material was in,
on, or under the Property as a result of Subtenant's negligence or wrongful
acts, (xix) costs incurred to comply with the Americans with Disabilities Act
except to the extent compliance is required because of amendment(s) to such law,
which amendment(s) became effective after the Commencement Date, (xx) costs for
sculpture, paintings, or other art, and (xxi) other expenses that under
generally accepted accounting principles consistently applied would not be
considered normal maintenance, operation or repair expenses.

      Section 6. Subtenant agrees to make monthly Annual Base Rent installments,
Additional Rent payments, Security Payments (as described in Article XXIII,
Section 1 below) and, if applicable, Swap Payment repayments (as described in
Article XXVI, Section 1 below) to Landlord by automatic electronic transfer. If
Subtenant does not pay the Annual Base Rent, Additional Rent or any other
charges due hereunder within five (5) days of when due, Subtenant shall pay
Landlord a late charge equal to five percent (5%) of such payment; and, if such
payment shall be made more than ten (10) days after such five (5) day grace
period, Subtenant shall in addition pay Landlord interest on such payment at the
rate of one percent (1%) per month from the date due until the date paid.

                                   ARTICLE IV

                          USE OF THE SUBLEASED PREMISES


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      Section 1. Subtenant shall use the Subleased Premises solely and
exclusively pursuant to the terms of this Sublease for office, research and
development, storage, or other activities incidental to and accessory to
Subtenant's business, and for no other purposes whatsoever without the written
consent of the Landlord.

      Section 2. Subtenant shall comply with all present and future laws, rules,
regulations, ordinances, requirements, and orders of public authorities relating
to Subtenant's use and occupancy of the Subleased Premises, including, without
limitation, building and zoning laws, requirements of Board of Health and
requirements of any other federal, state or local agencies having jurisdiction
of the Subleased Premises and the Building, including, without limitation, any
structural change required to be performed by Subtenant by any of the same.
Subtenant shall furthermore comply with all reasonable requirements of
Landlord's insurance carrier, and any Board of Fire Underwriters, or similar
bodies.

      Section 3. Subtenant shall be entitled to use Subtenant's Proportionate
Share of the parking areas on the Property as designated by Landlord.

                                    ARTICLE V

                                    UTILITIES

      Section 1. Subtenant shall pay all charges for utilities used exclusively
in the Subleased Premises (i.e., those utilities used in the Subleased Premises
that are not "Shared Utilities," as defined in Article V, Section 2 below)
whether such charges shall be made by a quasi-public or private utility company
or by a governmental authority or subdivision or department thereof. Subtenant
shall cause each such utility service to be separately metered to itself in its
name and shall be fully responsible for all costs in connection therewith. If
Landlord shall pay any of such charges on behalf of Subtenant, Subtenant shall
reimburse Landlord upon demand. Landlord shall not be responsible to Subtenant
for the failure or interruption of any such utilities unless such failure or
interruption is caused by the gross negligence or willful misconduct of Landlord
or his agents.

      Section 2. "Shared Utilities" shall mean utilities serving the Building as
a whole (e.g., gas, electricity and water) and the maintenance and repair of
related common mechanical systems and equipment (e.g., HVAC and electrical
systems). Landlord and Subtenant shall share responsibility for the expenses,
costs, and disbursements to third parties incurred in connection with Shared
Utilities. All Shared Utilities shall remain in Landlord's name and Landlord
shall pay the utility suppliers. Subtenant shall reimburse Landlord for its
portion of such expenses, costs, and disbursements as set forth in Article V,
Section 3. Landlord shall not be responsible to Subtenant for the failure or
interruption of any Shared Utilities unless such failure or interruption is
caused by the gross negligence or willful misconduct of Landlord or his agents.
Beginning promptly after the Commencement Date, and sooner if feasible, Landlord
shall retain and pay an energy consultant to develop a cost reduction strategy
for Shared Utilities and a contractor to


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implement the energy consultant's recommended improvements. The parties estimate
that the total cost of such work will be approximately $40,000 ("Program
Costs"). In no event shall Program Costs exceed $50,000.

      Section 3. Subtenant's portion of expenses, costs, and disbursements to
third parties incurred in connection with Shared Utilities shall be determined
as set forth below. If at any time during the Term or the Extension Period, if
any, the cost of electricity or gas changes from the cost of such utilities
during the Reference Year (as defined below), Landlord and Subtenant agree to
make mutually acceptable appropriate changes to Exhibit B to preserve the
intended economics of this Article V, Section 3.

      (a)   First Six Months of Term.

            (1)   During the first six months of the Term, Subtenant shall make
                  monthly estimated payments to Landlord for Shared Utilities
                  ("Estimated Payments"). Each Estimated Payment shall be equal
                  to Subtenant's costs in the same calendar month as set forth
                  in Exhibit B. Exhibit B shows the amounts incurred by
                  Subtenant and Landlord respectively at their former properties
                  for the period December 1, 2003 through November 30, 2004 (the
                  "Reference Year"). By way of clarification, Subtenant's
                  Estimated Payment for May during the first six months of the
                  Term would be $18,295, which is the corresponding amount for
                  May in the Reference Year.

            (2)   Within fifteen (15) days of the end of the first six months of
                  the Term, Landlord shall determine the actual amount spent for
                  Shared Utilities (the "Actual Amount"). The Actual Amount then
                  shall be compared to the total Estimated Payments made by
                  Subtenant during the first six months of the Term plus
                  Landlord's total costs at his former property during the
                  corresponding six calendar months in the Reference Year as
                  shown in Exhibit B (together, the "Reference Amount"). By way
                  of clarification, if the first six months of the Term are May
                  2005 through October 2005, then the Reference Amount shall be
                  $165,903 (total costs incurred by both Landlord and Subtenant
                  during the months May 2004 through October 2004 at their
                  former properties).

                  (i)   If the Actual Amount is less than the Reference Amount,
                        the difference shall be deemed "Savings." Savings shall
                        first be applied to reimburse Landlord for the Program
                        Costs. If a balance remains after such reimbursement,
                        Landlord shall pay Subtenant fifty percent (50%) of such
                        balance.

                  (ii)  If the Actual Amount is greater than the Reference
                        Amount, the difference shall be deemed "Excess." In the
                        event of an Excess, Subtenant shall pay Landlord fifty
                        percent (50%) of the Excess.


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      (b)   Second Six Months of Term.

            (1)   During the second six months of the Term, Subtenant shall make
                  monthly Estimated Payments to Landlord that are adjusted to
                  reflect the percentage of Savings realized by Subtenant in the
                  first six months of the Term ("Adjusted Estimate Payments").
                  Each Adjusted Estimated Payment shall be equal to Subtenant's
                  costs in the same calendar month as set forth in Exhibit B
                  reduced by a fraction the numerator of which is the Savings
                  from the first six months of the Term divided by two, and the
                  denominator of which is the total Estimated Payments made by
                  Subtenant during the first six months of the Term.

            (2)   Within fifteen (15) days of the end of the second six months
                  of the Term, Landlord shall determine the Actual Amount for
                  such period and compare it to the Reference Amount for such
                  period.

                  (i)   If the Actual Amount is less than the Reference Amount,
                        there shall be Savings for the second six months of the
                        Term. Landlord shall be entitled to fifty percent (50%)
                        of such Savings. Landlord shall subtract the following
                        from the other fifty percent (50%) and, if a balance
                        remains, shall pay such balance to Subtenant: (x) any
                        unpaid Program Costs; and (y) the difference between
                        Subtenant's Estimated Payments for the second six months
                        of the Term and the Adjusted Estimated Payments for the
                        same period.

                  (ii)  If the Actual Amount is greater than the Reference
                        Amount such that there is an Excess for the second six
                        months of the Term, Subtenant shall pay Landlord fifty
                        percent (50%) of such Excess.

      (c)   Third Six Months of Term.

            Determined using the methodology for the second six months of the
            Term.

      (d)   Extension Period.

            (1)   If there is an Extension Period, Subtenant shall make monthly
                  Estimated Payments to Landlord.

            (2)   Within fifteen (15) days of the end of each six months of the
                  Extension Period, Landlord shall determine the actual amount
                  spent for Shared Utilities during the applicable six month
                  period and deduct Landlord's total costs at his former
                  property during the corresponding six calendar months in the
                  Reference Year as shown in Exhibit B (the "Extension Actual
                  Amount"). The Extension Actual Amount then shall be compared
                  to the total Estimated


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                  Payments made by Subtenant during the applicable six month
                  period (the "Extension Reference Amount").

                  (i)   If the Extension Actual Amount is less than the
                        Extension Reference Amount such that there are Savings
                        for the applicable six month period, Landlord pay
                        Subtenant one hundred percent (100%) of such Savings.

                  (ii)  If the Extension Actual Amount is greater than the
                        Extension Reference Amount such that there is an Excess
                        for the applicable six month period, Subtenant shall pay
                        Landlord one hundred percent (100%) of such Excess.

                                   ARTICLE VI

                                     REPAIRS

      Section l. Subject to the other terms of this Sublease, including Article
V, Section 2 and those terms relating to fire or other casualty, Landlord at its
expense shall keep the roof, structure, and mechanical systems in or on the
Building in good order and repair; provided, however, that Subtenant shall
reimburse Landlord for the reasonable cost of such repairs to the extent the
repairs are caused by the negligence or misconduct of Subtenant, its employees,
contractors, agents and guests, and to the extent that the cost of the repairs
are not covered by insurance that Landlord is required to maintain under this
Sublease. Notwithstanding anything to the contrary contained in this Sublease,
Subtenant shall be responsible, at its sole expense, for keeping any mechanical
systems that exclusively serve the Subleased Premises in good order and repair.

      Section 2. Throughout the Term, Subtenant agrees to maintain the Subleased
Premises and all additions and improvements made upon them in good order and
repair, reasonable wear and tear and damage by fire or other casualty excepted.

                                   ARTICLE VII

                          RULES, REGULATIONS AND SIGNS

      Section 1. Subtenant shall comply with all reasonable rules and
regulations from time to time promulgated in writing by Landlord, provided that
the same are applicable to all Subtenants and occupants of the Building and do
not conflict with any right expressly granted to Subtenant in this Sublease.
Without consent from Landlord, Subtenant shall not: (a) keep or permit any
outside display or sales, nor place, maintain or permit any signs, placards,
lettering, awnings, aerials, flagpoles, decorations or the like or other
installations upon the exterior or roof of the Building, except for (i) a sign
on or near the front entrance of the Building indicating the location


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of the entrance to the Subleased Premises and (ii) a sign on or near the
entrance to the Subleased Premises indicating the same; or (b) make any holes in
or outside the Building, except as may be necessary for installation or removal
of any approved signs or approved alterations or trade fixtures and equipment
(Subtenant hereby agreeing that upon vacating the Subleased Premises it shall
repair any and all damage caused by any such installation or removals).

                                  ARTICLE VIII

                            ALTERATIONS BY SUBTENANT

      Section 1. Subtenant shall not make any alterations costing in excess of
$50,000 in the Subleased Premises without the prior written consent of Landlord,
which consent shall not be unreasonably withheld or delayed. Prior to the
commencement of any construction within the Subleased Premises, Subtenant shall
submit plans and specifications to Landlord for its approval. All work performed
by Subtenant shall be done in a good and workmanlike manner and in full
compliance with all laws and ordinances, and using materials of quality at least
equal to those employed in the rest of the Building. Upon completion of the
work, Subtenant shall deliver to Landlord sworn statements and lien waivers
evidencing that such work has been fully paid for. Subtenant shall indemnify and
hold Landlord harmless from all claims, liabilities and expenses (including
reasonable attorneys' fees) in connection with such work, including any mechanic
liens, and shall cause all such mechanic liens to be discharged, bonded or
insured over in a manner satisfactory to Landlord.

                                   ARTICLE IX

                       COVENANTS OF SUBTENANT AND LANDLORD

      Section 1. Subtenant shall throughout the Term hereof maintain the
Subleased Premises in safe condition and repair, reasonable wear and tear and
damage by fire or other casualty excepted, free from rubbish, dirt, refuse, or
garbage; store all trash and garbage in approved receptacles within the
Subleased Premises; handle all delivery and receiving of merchandise, supplies
and other materials to and from the Subleased Premises through service areas
provided for such use, if any; use the Common Area and other common areas in a
proper manner and with due regard to the rights of others; notify Landlord
promptly after the same shall come to the attention of Subtenant of the need for
any repairs or replacements to the Building.

      Section 2. Subtenant shall not during the Term hereof injure, overload or
deface the Subleased Premises or the Building, nor permit nor suffer any use of
the Subleased Premises, nor make any use of the Building or of the Subleased
Premises, that will be improper, offensive, or contrary to law, or liable to
invalidate any insurance, whether against risks of loss to persons or property,
or otherwise, or which will be injurious to any person or property or which will
constitute any waste or nuisance; and Subtenant shall pay any increase or extra
premium payable for such insurance resulting from any act done by Subtenant, or
any other increase in insurance premiums resulting from non-compliance of its
obligations under this Sublease. The statement of the insurer shall be
conclusive, as to the cause of such increased or extra premium, unless


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Subtenant shall establish to Landlord's reasonable satisfaction that Subtenant
is not responsible for such increased or extra premium.

      Section 3. To a standard consistent with Subtenant's former ownership and
occupancy of the Property, Landlord shall during the Term ensure the provision
of gas, electricity, water, HVAC service, and other such utilities, and
landscaping, plowing, maintenance of the Common Area and other common areas, and
similar services to and for the benefit of the Subleased Premises.

                                    ARTICLE X

                              ENVIRONMENTAL MATTERS

      Section 1. Subtenant shall not violate and shall promptly remedy or
correct any violations by it of any federal, state or local laws, rules and
regulations now or hereafter in effect with respect to Hazardous Material, as
defined below, introduced to the Subleased Premises. Subtenant shall not use all
or any portion of the Subleased Premises for the generation, storage, treatment,
use or disposal of any Hazardous Material except in compliance with all
applicable laws. Without limitation, express or implied, upon any other
requirements of this Sublease, Subtenant shall pay all such sums and take all
such actions as may be required to avoid or discharge the imposition of any lien
on the Subleased Premises resulting from Subtenant's violation of Massachusetts
General Laws, Chapter 21E, Comprehensive Environmental Response, Compensation,
and Liability Act, 42 U.S.C. Section 9601 et seq., or any other federal, state,
local or other statute, law, ordinance, code, rule, regulation, order or decree
regulating, relating to or imposing liability or standards of conduct concerning
any Hazardous Material, and Subtenant shall indemnify and save harmless Landlord
and Landlord's mortgagee from any and all reasonable losses, claims, liabilities
and expenses, including, without limitation, reasonable attorneys' fees incurred
or suffered by Landlord by virtue of Subtenant's violation of the provisions
thereof as applied to the Subleased Premises. The provisions of this Article X,
Section 1 shall survive the termination of this Sublease.

      Section 2. For purposes of this Sublease, "Hazardous Material" means and
includes any hazardous substance or any pollutant or contaminant defined as such
in (or for purposes of) the federal, state, or local statute, law, ordinance,
code, rule, regulation, order, or decree regulating, relating to, or imposing
liability or standards of conduct concerning, any hazardous, toxic or dangerous
waste, substance or material, as may now or at any time in the future be in
effect, or any other hazardous, toxic or dangerous waste, substance, or
material.

                                   ARTICLE XI

                                LANDLORD'S ENTRY

      Section 1. Landlord shall have the right to enter upon the Subleased
Premises at all reasonable business hours upon reasonable notice (and at any
time in case of an emergency) for the purpose of inspecting or exhibiting the
same, or for the purpose of making repairs to the


                                       11
<PAGE>

Subleased Premises, or for any other purpose or purposes contemplated in this
Sublease; provided, however, that none of the same shall be construed to impose
upon Landlord any obligation or liability whatsoever for the care, supervision
or repair of the Subleased Premises other than as expressly provided in this
Sublease; and provided further, that, Landlord must be accompanied by an
employee of Subtenant during each such entry (except in the case of an emergency
as discussed below), shall abide by all safety and other rules and regulations
of Subtenant, and agrees to hold in confidence and not use for any purpose any
confidential or proprietary information of Subtenant received or observed during
such entry. Landlord shall not, by reason of any inspection, be deemed to have
received notice of any condition with respect to which Landlord is obligated to
take any action under this Sublease. If Subtenant or its employees shall not be
present to permit entry into said Subleased Premises and if at any time, due to
emergency, an entry therein shall be necessary, Landlord or its agents may enter
the Subleased Premises, forcibly, if necessary, to prevent injury to persons or
damage to property without in any way rendering Landlord or its agents liable
therefor or without affecting Subtenant's obligations contained in this
Sublease. Landlord shall use all reasonable efforts to minimize any material
inconvenience to Subtenant in exercising its rights hereunder.

                                   ARTICLE XII

                                 INDEMNIFICATION

      Section 1. To the fullest extent permitted by law, Subtenant agrees to
indemnify and save Landlord harmless against any and all bodily and personal
injury, loss, claim or damage to any person or property while on the Subleased
Premises, and from and against all bodily and personal injury, loss, claim or
damage to any person or property anywhere in the Building or on the Property
caused by any wrongful act or omission or the negligence of Subtenant or of
Subtenant's employees, agents, licensees, invitees or any other person for whom
Subtenant is responsible, or caused by a default in the proper performance of
Subtenant's obligation under the terms of this Sublease; provided, however, that
Subtenant shall have no such indemnification obligations to the extent that any
such injury, loss, claim or damage is caused by the wrongful act or omission or
the negligence of Landlord, or of Landlord's employees, agents, licensees,
invitees or any other person for whom Landlord is responsible, or caused by a
default in the proper performance of Landlord's obligation under the terms of
this Sublease.

      Section 2. To the fullest extent permitted by law, Landlord agrees to
indemnify and save Subtenant harmless against any and all bodily and personal
injury, loss, claim or damage to any person or property while on the Subleased
Premises, and from and against all bodily and personal injury, loss, claim or
damage to any person or property anywhere in the Building or on the Property
caused by any wrongful act or omission or the negligence of Landlord or of
Landlord's employees, agents, licensees, invitees or any other person for whom
Landlord is responsible, or caused by a default in the proper performance of
Landlord's obligation under the terms of this Sublease; provided, however, that
Landlord shall have no such indemnification obligation to the extent that any
such injury, loss, claim or damage is caused by the wrongful act or omission or
the negligence of Subtenant, or of Subtenant's employees, agents, licensees,
invitees or any other person for whom Subtenant is responsible, or caused by a
default in the proper performance of Subtenant's obligation


                                       12
<PAGE>

under the terms of this Sublease.

                                  ARTICLE XIII

                                    SURRENDER

      Section 1. At the expiration or prior termination of the Sublease,
Subtenant shall surrender the Subleased Premises in good condition, reasonable
wear and tear and damage by fire or other casualty excepted.

      Section 2. All personal property and trade fixtures owned by Subtenant
that can be removed without substantial physical injury to the Subleased
Premises shall remain the property of Subtenant and shall be removed by
Subtenant no later than the expiration or termination of the Sublease; provided,
however, that if Subtenant is in default under this Article XIII, Section 2 or
if any such property shall not be removed by the expiration or termination of
this Sublease, such property shall, at the express written election of Landlord,
be deemed to have become Landlord's property. Furthermore, in such event,
Landlord may dispose of any of Subtenant's property not so removed at
Subtenant's risk and expense. Subtenant shall repair any and all damage caused
by the removal of Subtenant's personal property and trade fixtures.

                                   ARTICLE XIV

                                    INSURANCE

      Section 1. During the Term, Subtenant shall maintain in full force and
effect the following insurance, written by one or more insurance companies
licensed to do business in the Commonwealth of Massachusetts having a Best
rating of A or better, class VIII or better:

      A. Workmen's compensation insurance covering all employees, and if
Subtenant shall contract with any independent contractor for the furnishing of
labor, materials or services to Subtenant, Subtenant shall require such
independent contractor to maintain workmen's compensation insurance covering all
its employees and all the employees of any subcontractors. Subtenant shall also
maintain employers liability insurance having limits of not less than
$1,000,000.

      B. Property insurance with standard extended coverage in an amount of not
less than one hundred percent (100%) of the full sound insurable value of all of
Subtenant's property and, if the Subleased Premises shall be sprinkled,
sprinkler insurance in an amount of not less than one hundred percent (100%) of
the full sound insurable value thereof. Said coverage shall include explosion
and boiler insurance if appropriate.

      C. Commercial general liability insurance with limits of $2,000,000 as
provided in the comprehensive general liability forms with contractual liability
endorsements attached, in companies qualified to do business in the Commonwealth
of Massachusetts, insuring against injury to persons and damage to property as
herein provided, naming Landlord and Landlord's


                                       13
<PAGE>

Mortgagee as additional insureds thereunder. Such insurance may be carried by
Subtenant under a blanket or umbrella coverage.

      D. Comprehensive automobile liability insurance covering all owned,
non-owned and hired vehicles, with limits of not less than $1,000,000 combined
single limit for personal injury and property damage.

      Section 2. During the Term, Landlord shall maintain in full force and
effect the following insurance, written by one or more insurance companies
licensed to do business in the Commonwealth of Massachusetts having a Best
rating of A or better, class VIII or better:

      A. Landlord shall, throughout the term of this Sublease, keep the Building
and all other improvements on the Property insured pursuant to one or more
policies of property insurance written on an "all risk" of physical loss or
damage basis in such amounts as would be equal to one hundred percent (100%)
replacement cost of the Building and all other improvements on the Property, as
is necessary to avoid co-insurance.

      B. Commercial general liability insurance with coverage for
premises/operations, personal injury, and contractual liability with combined
single limits of liability of not less than $2,000,000 for bodily injury and
property damage per occurrence. This limit can be made through a combination of
a primary commercial general liability policy and an umbrella policy or other
multi-property "blanket" coverage.

      Section 3. Each policy of insurance placed by Subtenant under this
Sublease shall provide that such policy may not be canceled without at least
thirty (30) days prior written notice to Landlord and Landlord's Mortgagee. Each
policy of insurance placed by Landlord under this Sublease shall provide that
such policy may not be canceled without at least thirty (30) days prior written
notice to Subtenant. Each party shall furnish such policy or a certificate by
the insurer as to the existence thereof to the other party at least thirty (30)
days prior to the Commencement Date and thereafter at least fifteen (15) days
prior to the expiration thereof or of any modification or renewal of such
policy. Each of said policies shall be written on an annual basis with premiums
to be prepaid yearly, and evidence of such payment shall be given to the other
party not less than fifteen (15) days prior to the expiration of such policy.

      Section 4. Each of Landlord and Subtenant hereby reSubleases the other
(and each person and legal entity claiming through each of them) from any and
all liability or responsibility to the other (and each person and legal entity
claiming through the other) by way of subrogation or otherwise for any loss or
damage to property caused by fire or any of the extended coverage casualties, or
by sprinkler leakage, even if such fire or other casualty or such leakage shall
have been caused by the fault or negligence of the other party, or anyone for
whom such party may be responsible. This mutual waiver precludes the assignment
of any such claim by subrogation to an insurance company (or any other person),
and Landlord and Subtenant each agree to give written notice of this waiver to
each insurance company that has issued or shall issue any property insurance
policy to it, and to have the policy properly endorsed with provisions that
either designate the other party as one of the insureds or deny to the insurer
acquisition by


                                       14
<PAGE>

subrogation of rights of recovery against the other party to the extent such
rights have been waived by the insured party, as set forth herein, insofar as,
and to the extent that such provisions may be effective without making it
impossible to obtain insurance coverage from responsible companies qualified to
do business in the Commonwealth of Massachusetts (even though extra premium may
result therefrom). Each party shall be entitled to have certificates of
insurance with respect to such policies containing such provisions. In addition,
and without limiting the foregoing, each of Landlord and Subtenant waives any
and every such claim against the other that would have been covered had the
insurance policies required to be maintained by such person by this Sublease
been in force, to the extent that such loss or damage would have been
recoverable under such policies, whether or not the same have been maintained.


                                   ARTICLE XV

                    DAMAGE OR DESTRUCTION BY FIRE OR CASUALTY

      Section 1. If so much of the Building shall be damaged or destroyed so
that the remainder of the Building becomes uneconomic for Landlord's use in the
good faith judgment of Landlord or if the time to repair the Building would
exceed one hundred eighty (180) days, Landlord may terminate this Sublease by
giving notice to Subtenant within thirty (30) days of such event.

      Section 2. If this Sublease shall not be so terminated, Landlord, within a
reasonable time, having in mind delays resulting from the settlement of any
insurance loss, preparation of plans and obtaining permits, shall commence to
restore the Subleased Premises. Landlord shall proceed reasonably diligently
with such restoration. Landlord shall not be obligated to expend more than
Landlord shall receive as insurance proceeds or otherwise on account of such
damage or destruction, before taking into account deductions for deductibles or
co-insurance. If Landlord fails to proceed with reasonable diligence or fails to
complete restoration within ninety (90) days of its estimated completion date,
Subtenant may, as its sole and exclusive remedy, terminate this Sublease by
written notice to Landlord.

      Section 3. If the Subleased Premises shall be damaged and if this Sublease
shall not be terminated as herein provided, then the Annual Base Rent and
Subtenant's Proportionate Share for all purposes shall be reduced for the
portion of the Subleased Premises that cannot be used as a result of such damage
until the Subleased Premises shall have been restored to its former condition.

                                   ARTICLE XVI

                                 EMINENT DOMAIN

      Section 1. If after the Commencement Date the whole or substantially all
of the Subleased Premises shall be taken under the power of eminent domain or by
purchase in lieu thereof by any public, quasi-public or private authority, or
condemned as unlawful, or suffer any


                                       15
<PAGE>

damage that shall entitle Landlord to make a claim for injury to the Building
arising to the level of a taking, direct or consequential, all herein referred
to as "Taking," then this Sublease shall, at the election of Landlord by written
notice to Subtenant, be terminated.

      Section 2. If after the Commencement Date:

      (i)   the aggregate of all reductions of the floor area of the Subleased
            Premises shall equal or exceed twenty (20%) or more of the original
            floor area of the Subleased Premises; or

      (ii)  the Building shall be permanently deprived of access by motor
            vehicle to and from a public street or private way,

then, in either such case, Subtenant shall have the right at its election to
terminate this Sublease by giving Landlord notice of its election within thirty
(30) days after such event; provided, however, in the case of (ii) that if
Landlord shall have undertaken to provide substitute access and Landlord shall
have completed the same within thirty (30) days, Subtenant's notice of
termination shall be void.

      Section 3. All damages awarded for any Taking, whether for the whole or a
part of the Subleased Premises, or the Building or otherwise, shall belong to
and be the sole property of the Landlord whether such damages shall be awarded
as compensation for diminishing the value of the Subleasehold, fee or otherwise,
and Subtenant does hereby assign to Landlord all of its right, title, and
interest thereto; provided, however, that Subtenant shall be entitled to receive
and retain any amounts which may be specifically awarded to it by reason of the
loss of its furniture or trade fixtures or for moving expenses. Subtenant agrees
to execute and deliver any document necessary or desirable to confirm Landlord's
rights under this Article XVI, Section 3.

      Section 4. If this Sublease shall not be terminated as provided in Article
XVI, Section 1, Landlord shall, within a reasonable period of time after such
damage, commence to restore the damage or destruction to the Subleased Premises.
Landlord shall proceed with reasonable diligence to the completion of such
restoration so that they shall have been restored as nearly as possible to the
condition they were in prior to such damage. If Landlord fails to proceed with
reasonable diligence or fails to complete restoration within ninety (90) days of
its estimated completion date, Subtenant may, as its sole and exclusive remedy,
terminate this Sublease by written notice to Landlord. If the net award after
all costs and expenses incurred by Landlord in the collection thereof shall not
be sufficient to restore the Building, Landlord may terminate this Sublease by
written notice to that effect to the Subtenant.

      Section 5. During the period of restoration, the Annual Base Rent reserved
hereunder shall be suspended or abated according to the proportion of the floor
area of the Subleased Premises rendered unusable and Subtenant's Proportionate
Share for all purposes shall be adjusted in accordance with Article III, Section
3. There shall be no abatement or suspension of Rent hereunder if there shall be
no actual physical damage to the Subleased Premises, nor, in any case shall
there be an abatement of Subtenant's obligation to pay other charges due under
this


                                       16
<PAGE>


Sublease. If Subtenant shall be permanently deprived of any portion of the floor
area of the Subleased Premises, the Annual Base Rent shall be proportionally
abated for the balance of the Term (including the Extension Period, if
applicable) to reflect the then size of the Subleased Premises and the Building
and Subtenant's Proportionate Share for all purposes shall be adjusted in
accordance with Article III, Section 3.

                                  ARTICLE XVII

                                SUBTENANT DEFAULT

      Section 1. Subtenant shall be deemed in default hereunder if, after
receipt from Landlord of the required notice and the expiration of the
applicable cure period (each as described more fully below), (a) Subtenant shall
neglect or fail to make any payment of Annual Base Rent, Additional Rent or
other payments to be made by it hereunder or shall neglect or fail to perform or
observe any of the other material covenants and agreements contained in this
Sublease and on its part to be performed or observed, (b) the estate created
hereby shall be taken upon execution, attachment, or any other process of law
and such process shall not be rendered inoperative within twenty (20) days
thereafter, (c) Subtenant shall be adjudged a bankrupt or insolvent, or if any
receiver or trustee of all or any part of the business or property of Subtenant,
wherever located, shall be appointed and shall not be discharged within ninety
(90) days after appointment, (d) Subtenant shall make any general assignment of
its property for the benefit of creditors, or if Subtenant shall file a
voluntary petition in bankruptcy or insolvency or shall apply for reorganization
or arrangement with its creditors under the bankruptcy or insolvency laws now in
force or hereinafter enacted, federal, state or otherwise, or if any such
petition shall be filed against Subtenant and shall not be discharged within
ninety (90) days after the filing, provided that the rent and all other monetary
obligations of Subtenant shall be paid, or (e) Subtenant shall seek a
composition with its creditors by trust mortgage or otherwise. Anything herein
contained to the contrary notwithstanding, Subtenant shall not be in default
until it receives written notice from Landlord of one or more of (a) through (e)
above, as applicable, and is given the opportunity to cure the same, as follows.
If such potential default shall relate to the payment of money, Subtenant shall
have five (5) days to make payment. If such potential default shall be other
than the payment of money, Subtenant shall have thirty (30) days to cure,
provided that if the potential default complained of is of such character that
it reasonably requires more than thirty (30) days to cure the same, Subtenant
shall have a reasonable period of time, not to exceed sixty (60) days,
subsequent to such thirty (30) day period, provided that Subtenant shall
commence to cure such potential default within such thirty (30) day period and
proceed diligently until completion of such cure. Landlord shall not exercise
any remedy hereunder if Subtenant shall complete the cure of any potential
default within the time periods allowed above.

      Section 2. If Subtenant shall be in default under this Sublease as
specified in Article XVII, Section 1 above, then in any such case Landlord may
terminate this Sublease upon notice to Subtenant, and this Sublease shall come
to an end on the date of such notice (or such other date specified for
termination therein) as fully and completely as if such date were the date
herein originally fixed for the expiration of the Term, and Subtenant will then
quit and surrender the Subleased Premises to Landlord, but Subtenant shall
remain liable as hereinafter provided. If


                                       17
<PAGE>

Subtenant is in default hereunder, Landlord also shall have the right when it
delivers notice of termination or at any time thereafter, to enter upon the
Subleased Premises or any part thereof in the name of the whole and repossess
the same as of its former estate and expel Subtenant and those claiming by,
through or under it, and remove their goods and effects without being deemed
guilty of any manner of trespass and without prejudice to any remedies which
might otherwise be used for arrears of rent or other payments or preceding
breach of covenant.

      Section 3. In the event of termination under Article XVII, Section 2,
Subtenant shall pay to Landlord, as liquidated current damages, the Annual Base
Rent, Additional Rent and other sums that would be payable hereunder for the
remainder of the Term, or the Extension Period if the option under Article II,
Section 2 was already exercised, if such termination had not occurred, less the
net proceeds, if any, of any reletting of the Subleased Premises, after
deducting all reasonable expenses in connection with such reletting, including,
without limitation, all repossession costs, brokerage commissions, legal
expenses, attorneys' fees, and advertising for such reletting. Subtenant shall
pay the liquidated current damages to Landlord monthly on the days when the
Annual Base Rent would have been payable hereunder if this Sublease had not been
terminated. Landlord shall apply the Security Payments provided for in Article
XVII, Section 2 to the liquidated current damages.

      Section 4. If Subtenant shall be in default hereunder, Landlord may, at
its option, without waiving any claim for breach of agreement, at any time
thereafter cure such default for the account of Subtenant, and Subtenant shall
reimburse Landlord for any amount paid and any expense or contractual liability
so incurred, including reasonable attorneys' fees. Landlord may cure the default
of Subtenant prior to the expiration of the cure period, but only after notice,
which notice need not be in writing if confirmed forthwith by notice in writing
to the Subtenant if it is necessary to protect the real estate or the interest
of Landlord therein or to prevent injury or damage to persons or property. Any
amount payable by Subtenant to Landlord pursuant to the provisions of this
Article XVII, Section 4 shall be paid as part of and at the time for payment of
the next installment of Annual Base Rent thereafter coming due.

                                  ARTICLE XVIII

                               LANDLORD'S DEFAULT

Section 1. Landlord's failure to perform or observe any of its Sublease
obligations after a period of thirty (30) business days or the additional time,
if any, that is reasonably necessary to promptly and diligently cure the failure
after receiving notice from Subtenant, or such lesser time as expressly provided
elsewhere in this Sublease, is a default. The notice shall give in reasonable
detail the nature and extent of the failure and identify the Sublease
provision(s) containing the obligation(s). If Landlord commits a default,
Subtenant may pursue any remedies given in this Sublease or under the law,
provided, however, that in no event (unless otherwise specified herein) shall
Subtenant have a right to offset Annual Base Rent or Additional Rent as a result
of an alleged default hereunder.


                                       18
<PAGE>

                                   ARTICLE XIX

                            ASSIGNMENT AND SUBLETTING

      Section 1. Except as herein expressly set forth, Subtenant shall not
assign this Sublease nor any estate of interest therein, nor sublet or license
the whole or any part of the Subleased Premises, all of which are herein
referred to as a "Transfer," without the prior written consent of Landlord, not
to be unreasonably withheld or delayed. Subtenant may Transfer its interest to
any parent corporation or wholly-owned subsidiary corporation or wholly-owned
subsidiary of any parent corporation without such consent, provided that in each
case Subtenant shall give notice of such Transfer to Landlord. Each such
assignee shall assume the obligations of the Subtenant hereunder. Subtenant
shall remain liable to Landlord during the Term (including the Extension Period,
if applicable) for the payment of rent and the performance of all obligations of
Subtenant hereunder. Consent by Landlord to one or more Transfers shall not
operate to exhaust Landlord's right to refuse consent to any future Transfer.
Subtenant shall notify Landlord promptly of any proposed Transfer.

                                   ARTICLE XX

                            OVERSUBLEASES, MORTGAGES

      Section 1. At the election of Landlord, or any future mortgagee, or any
person who is or shall become the owner of the fee of the Building and who has
or shall Sublease the same to Landlord, herein "Overlessor," which election may
be changed from time to time, this Sublease and the Subtenant's rights hereunder
shall be subject and subordinate to such mortgage or OverSublease; provided that
such mortgagee or Overlessor shall first enter into a written instrument in
recordable form and otherwise in form reasonably satisfactory to Subtenant,
which provides that so long as no default, after the giving of any required
notice and expiration of all grace or cure periods, is continuing hereunder: (i)
this Sublease will not be affected and will continue as a direct Sublease
between Subtenant and any such mortgagee or Overlessor and their assignees,
nominees or successors (including, but not limited to, purchasers at a
foreclosure sale) taking title to the Building or the Property or otherwise
succeeding to the interest of Landlord hereunder, (ii) such mortgagee or
Overlessor shall be prospectively bound to Subtenant under the terms of this
Sublease (including Subtenant's right to extend the Term hereof), (iii)
Subtenant's possession hereunder will not be disturbed by any default in,
termination, foreclosure of, exercise of any remedy under such mortgage or
OverSublease and/or any conveyance in lieu of the exercise thereof, as the case
may be and (iv) Subtenant shall attorn to such mortgagee or Overlessor hereunder
upon such mortgagee or Overlessor or their assignees, nominees or successors
(including, but not limited to, purchasers at a foreclosure sale) taking title
to the Building or the Property or otherwise succeeding to the interest of
Landlord hereunder. Subtenant shall, upon request of Landlord, such mortgagee,
or Overlessor, execute any documents which may be necessary to evidence or
confirm such subordination.


                                       19
<PAGE>

      Section 2. Subtenant shall, upon receipt of written notice from any such
mortgagee, Overlessor, or other person to whom Landlord may from time to time
assign the rents or other payments due hereunder, make payment of such rents or
other payment to such person and shall be fully protected in making such
payment. Landlord shall advise Subtenant in writing if Landlord shall hereafter
grant a mortgage or OverSublease or otherwise assign the rents hereunder.

                                   ARTICLE XXI

                                     BROKER

      Section 1. Landlord and Subtenant warrant and represent to each other that
neither has dealt with any broker or agent in connection with this Sublease
except Meredith & Grew Incorporated and Richards Barry Joyce & Partners, and
that no other broker or agent has been instrumental in this transaction. Both
parties agree to indemnify the other against any claim, loss, damage, cost or
liability for any brokerage commission or fee which may be asserted against
either party in connection with this Sublease by any other broker with whom
either party has dealt.

                                  ARTICLE XXII

                                     NOTICES

      Section 1. Except as specifically otherwise provided in this Sublease, all
notices and other communications authorized or required hereunder shall be in
writing and shall be given by mailing the same by certified or registered mail,
return receipt requested, postage prepaid, or by expedited overnight courier
utilizing receipt, or by facsimile confirmed in one of the foregoing methods,
and any such notice shall be deemed to have been given when so mailed. If
intended for Landlord, the same shall be mailed to Landlord at:

                        Dr. Frank Pompei
                        C/o Exergen Corporation
                        51 Water Street Watertown.
                        MA 02472

with a copy contemporaneously sent to:

                        Walter H. McLaughlin, Jr., Esq.
                        Gilman, McLaughlin & Hanrahan LLP
                        101 Merrimac Street
                        P.O. Box 9601
                        Boston, Massachusetts 02114-9601


                                       20
<PAGE>

with copies to such other parties as Landlord shall designate, and if intended
for Subtenant, the same shall be mailed to Subtenant at:

                        Control Delivery Systems, Inc.
                        400 Pleasant Street
                        Watertown, Massachusetts 02472
                        Attention: Cristin L. Rothfuss, Corporate Counsel

with a copy contemporaneously sent to:

                        Mary Weber, Esq.
                        Ropes & Gray, LLP
                        One International Place
                        Boston, MA 02110-2624

      All notices shall be effective upon receipt or the third business day
after deposit with the United States Post Office, postage paid.

                                  ARTICLE XXIII

                                SECURITY DEPOSIT

      Section 1. As security for its full and faithful performance of this
Sublease during the original Term, Subtenant shall make the following payments
(each a "Security Payment"): for each of the first six (6) months of the Term,
Subtenant shall make an $18,000 Security Payment to Landlord and commencing on
the seventh month of the Term and continuing until the total Annual Base Rent
for the original Term is paid in full, Subtenant shall make a $20,000 Security
Payment to Landlord each month. Each Security Payment shall be paid in
conjunction with and be in addition to Subtenant's monthly installment of Annual
Base Rent and Additional Rent. The first such Security Payment shall be applied
against the monthly installment of Annual Base Rent due for the eighteenth
(18th) month of the Term. The second such Security Payment shall be applied
against the balance for the monthly installment of Annual Base Rent due for the
eighteenth (18th) month of the Term, and the remainder shall be applied against
the monthly installment of Annual Base Rent due for the seventeenth (17th) month
of the Term. Other Security Payments shall be applied in the same manner (i.e.,
against the latest unpaid Annual Base Rent installment). Subtenant shall
continue to make such payments and such payments shall continue to be applied in
this manner until the total Annual Base Rent for the original Term is paid in
full.

      Section 2. In the event that this Sublease is terminated prior to the end
of the original Term, and so long as Subtenant is not in default under any of
the terms, provisions or conditions of this Sublease on the termination date,
Landlord shall refund to Subtenant any amounts paid by Subtenant in excess of
the Annual Base Rent due for the actual term length by virtue of the Security
Payment mechanism described in Article XXIII, Section 1.


                                       21
<PAGE>

                                  ARTICLE XXIV

                                  MISCELLANEOUS

      Section 1. In any case where either party hereto is required to do any
act, other than the making of any payment of rent or other monetary sum due
Landlord hereunder, the time for performance thereof shall be extended for a
period equal to any delay caused by or resulting from any act of God, war, civil
commotion, fire casualty, labor difficulties, shortages of labor, materials or
equipment, governmental regulations or other causes beyond such party's
reasonable control, whether such time be designated by a fixed date, a fixed
time, or a "reasonable time." In no event shall the parties inability to pay a
monetary sum be affected by this clause.

      Section 2. Failure of either party to complain of any act or omission on
the part of the other party, no matter how long the same may continue, shall not
be deemed to be a waiver by said party of any of its rights hereunder. No waiver
by either party at any time shall be effective unless in writing and signed by
the party adversely affected by the breach with respect to which waiver is
asserted to have been made. No waiver of any breach of any provision of this
Sublease shall be deemed a waiver of a breach of any other provision of this
Sublease or a consent to any subsequent breach of the same or any other
provision. If any action by either party shall require the consent or approval
of the other party, the other party's consent to or approval of such action on
any one occasion shall not be deemed a consent to or approval of said action on
any subsequent occasion or a consent or approval of any other action on the same
or any subsequent occasion. Each and every right and remedy which either party
may have under this Sublease or by operation of law, either at law or in equity,
with respect to any breach, shall be distinct and separate from every other such
right and remedy; all such rights and remedies shall be cumulative, and none of
them shall be deemed inconsistent with any other, no such right or remedy
whether or not exercised, shall be deemed to be in exclusion of any other, and
any two or more or all of such rights and remedies may be exercised at the same
time or successively, except where in this Sublease otherwise expressly
provided.

      Section 3. If any term or provision of this Sublease or the application
thereof to any person or circumstance shall, to any extent, be invalid or
unenforceable, the remainder of this Sublease, or the application of such term
or provisions to Persons or circumstances other than those as to which it is
held invalid or unenforceable, shall not be affected thereby, and each term and
provision of this Sublease shall be valid and be enforced to the fullest extent
permitted by law.

      Section 4. Except as herein otherwise provided, the terms and provisions
of this Sublease shall be binding upon and inure to the benefit of the heirs,
legal representatives, successors, and assigns respectively of Landlord and
Subtenant. This Article XXIV, Section 4 shall not be deemed to be any consent by
Landlord to an assignment hereof by Subtenant.

      Section 5. The headings used for the various Articles of this Sublease are
used only as a matter of convenience for reference, and are not to be construed
as part of this Sublease or to be


                                       22
<PAGE>

used in determining the intent of the parties to this Sublease.

      Section 6. This instrument constitutes the entire and only agreement
between the parties and no oral statements or representations or prior written
matters not contained in this Sublease shall have any force and effect. Except
as expressly provided in this Sublease, none of the exhibits herein referred to
or attached hereto shall in any way constitute any representation or warranty in
respect to the Building, the Subleased Premises, location of construction and
location of Buildings and improvements, occupancy by other Subtenants,
continuation of occupancy by other Subtenants, use by other Subtenants, nor
limitation on the construction of additional Buildings or additions to Building
by Landlord whether on the roof, if any, of the Subleased Premises, or
elsewhere. No subsequent amendments, changes, or additions to this Sublease
shall be binding upon Landlord or Subtenant unless reduced to writing and duly
executed by Landlord and Subtenant. Any pronoun shall be read in the singular or
plural in such gender as the context may require or permit.

      Section 7. Subtenant shall from time to time, upon request of Landlord,
furnish to Landlord or to any designee of Landlord, certifications as to the
status of this Sublease, the existence or non-existence of default on the part
of Landlord, or any state of fact or facts requested to be certified to by
Subtenant with reference to this Sublease.

      Section 8. Except as otherwise expressly set forth herein, this Sublease
is a net Sublease, and shall be interpreted to the end that the Annual Base Rent
and Additional Rent shall be payable to Landlord without offset or deduction in
any and all events, except as herein expressly set forth. Landlord shall have no
obligation hereunder except as expressly set forth in this Sublease.

      Section 9. So long as Subtenant shall not be in default, Subtenant may
peaceably and quietly occupy and enjoy the Subleased Premises and the use
thereof, without molestation of any person or any claims by, through or under
Landlord.

      Section 10. This Sublease may be executed in counterparts, each of which
shall be deemed an original and all of which, taken together, shall be deemed to
be one and the same instrument.

      Section 11. The liability of Landlord hereunder shall be limited solely to
the equity of Landlord in the Building and any sales or insurance proceeds
realized therefrom, and in no case shall Landlord or any partner or agent of
Landlord ever be personally liable beyond the extent of his or their equity in
the Building or such proceeds for the obligations of Landlord, except that any
of the same may be named in order to obtain jurisdiction of Landlord in any
litigation. Each Landlord hereunder shall be liable for the obligations of
Landlord only during such time as such person shall be Landlord and with respect
only to items occurring during such period of ownership.

      Section 12. The terms of this Sublease shall be not be disclosed by either
party to any


                                       23
<PAGE>

third party; provided, however, that each party may disclose such terms to its
financial advisors and potential investors or in connection with a potential
merger or acquisition, in each case under the auspices of a confidentiality
agreement.

                                   ARTICLE XXV

                                   WORK LETTER

      Section 1. Subtenant enters into this Sublease subject to Landlord's
agreement to complete certain demising work and improvements no later than sixty
(60) days after the Closing Date. In particular, Landlord agrees to complete all
work specified in Exhibit C. Landlord shall be responsible for all costs
associated with upgrading the bathrooms, as specified in Exhibit B. In addition,
Landlord shall be responsible for the first $25,000 of completing all other work
specified in Exhibit B and any Additional Work, as defined below. Landlord and
Subtenant shall each be responsible for fifty percent (50%) of the balance for
completing all other work specified in Exhibit B and any Additional Work.

      Section 2. Until the work associated with upgrading the bathrooms is
completed, Subtenant's employees and guests shall be entitled to use the
bathrooms in Landlord's portion of the Building. Landlord shall use all
reasonable efforts to minimize disruption to Subtenant's business during
performance of the work.

      Section 3. If, no later than six (6) months after the Commencement Date, a
local, state or federal governmental body having appropriate authority orders
Landlord to perform demising work beyond that specified in Exhibit B
("Additional Work"), Landlord shall complete the same. Landlord and Subtenant
shall be responsible for the cost of the Additional Work as set forth above. In
the event that Subtenant is responsible for any part of the cost of the
Additional Work, Landlord agrees to pay Subtenant's fifty percent (50%) share
and Subtenant agrees to increase each monthly payment of Annual Base Rent during
the remainder of the Term by an amount equal to such fifty percent (50%) share
divided by the remaining number of Annual Base Rent payments.

      EXECUTED as a Sealed Instrument on the day, month and year first above
written.


SUBTENANT:                              LANDLORD:

CONTROL DELIVERY SYSTEMS, INC.          EXERGEN CORPORATION


By: /s/ Michael J. Soja                 By: /s/ Francesco Pompei
   ----------------------------------      -------------------------------------
   Name:   Michael J. Soja                 Francesco Pompei, President
   Office: VP and CFO                      Hereunto duly authorized
   Hereunto duly authorized


                                       24
<PAGE>

Overlandlord hereby consents to this Sublease.

FHP, LLC

By: /s/ Francesco Pompei
   ------------------------------------
   Francesco Pompei, Manager


                                       25
<PAGE>

                                    EXHIBIT A

                                   FLOOR PLAN



                                       26
<PAGE>

                                    EXHIBIT B

                                 REFERENCE YEAR

AMOUNTS INCURRED BY LANDLORD AT HIS FORMER PROPERTY

<TABLE>
<CAPTION>
           Water/sewer    Maint. Contracts   Electric       Gas         TOTAL
           ---------------------------------------------------------------------
<S>        <C>            <C>                <C>         <C>          <C>
Dec-03     $     --                          $  3,275    $     962    $   4,237
Jan-04           --                             3,622        1,345        4,968
Feb-04           --                             2,655        1,102        3,756
Mar-04           --                             3,513        1,054        4,566
Apr-04           --                             3,513          418        3,931
May-04           --                             3,776           94        3,870
Jun-04           --                             6,796           93        6,889
Jul-04           --                             5,737           99        5,836
Aug-04           --                             6,924           94        7,018
Sep-04           --                             6,394           90        6,484
Oct-04           --                             6,394          366        6,761
Nov-04           --                             4,342          366        4,708
           ---------------------------------------------------------------------
Total      $     --          $      --       $ 56,941    $   6,084    $  63,025
           ---------------------------------------------------------------------
</TABLE>

AMOUNTS INCURRED BY SUBTENANT AT ITS FORMER PROPERTY

<TABLE>
<CAPTION>
           Water/sewer  Maint. Contracts    Electric         Gas          TOTAL
           ---------------------------------------------------------------------
<S>        <C>          <C>                 <C>           <C>           <C>
Dec-03      $    175        $  1,333        $ 11,139      $  6,931      $ 19,578
Jan-04           175           1,333          11,239         6,562        19,309
Feb-04           175           1,334          10,233         7,367        19,110
Mar-04           175           1,333           9,922         7,402        18,832
Apr-04           175           1,333          10,322         5,820        17,650
May-04           175           1,334          11,182         5,604        18,295
Jun-04           175           1,333          15,149         4,683        21,340
Jul-04           175           1,333          17,082         4,730        23,321
Aug-04           175           1,334          17,053         4,220        22,782
Sep-04           175           1,333          13,376         4,747        19,631
Oct-04           175           1,333          17,623         4,545        23,676
Nov-04           175           1,334           9,264         5,107        15,880
           ---------------------------------------------------------------------
Total       $  2,100        $ 16,000        $153,585      $ 67,717      $239,402
           ---------------------------------------------------------------------
</TABLE>


                                       27
<PAGE>


                                    EXHIBIT C

                                    WORK PLAN

<TABLE>
<S>    <C>                                                            <C>
1.
       Bottom of Ramp in entrance front of building, straighten
       approx. 20' of wall 10'h removing existing double swing
       door and reinstall in another location. Wall single
       thickness 5/8" sheet rock T.J.P.                               $   4,000

2.
       Back section of building straighten wall approx. 17'L x
       10'H. Removing existing doors and not reinstall with
       single 5/8 sheet rock T.J.P.                                   $   2,800

3.
       Building divider wall 34-6" x 10'h with two framed doors
       and hardware, to form a corridor to bath rooms. Includes
       drop ceiling, lighting, VT flooring. T.J.P with base cover.
       (Does not include sprinkler system)                            $   8,200

4.
       In same area cut open in existing wall to gain access to
       area, and baths. Includes, framing 36"x84" opening for
       frame and door with all hardware.                              $   1,400
5.
       Build diagonal wall at bottom of ramp with frame 36" crash
       bar door to match existing doors wall approx. 9'Lx10'H
       single 5/8 sheet rock both sides T.J.P.                        $   3,200
7.
       Install drop ceiling in space 34.5'x16' + 12"x16" adjacent
       to divider wall to baths includes; installing track for
       drop ceiling 2"x4" all ceiling tile and six 2'x4' light
       panels and switching.  Excluding flooring.                     $   4,200

8.     Frame and install sheet rock T.J.P. 6'x8' opening to divide
       office space in front of building                              $   1,000

9.     Ramp outside extend to 18'L. Build with pressure treated
       lumber and pipe rail.                                          $   2,800
                                                                      ---------
                                SUBTOTAL                              $  27,600

                   Contractor mark-up20%                              $   5,520
                                                                      ---------
                                TOTAL                                 $  33,120
                                                                      ---------
</TABLE>


                                       28