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                                                                   EXHIBIT 10.1

                                  SUB-SUBLEASE

         AGREEMENT OF SUB-SUBLEASE ("Sub-Sublease"), made as of the 11th day of
November, 2004, by and between BIOPURE CORPORATION, having an address at 11
Hurley Street, Cambridge, Massachusetts 02141 ("Sub-Sublandlord" hereinafter
also called "Landlord") and SENIOR WHOLE HEALTH, LLC, having its principal
office at 101 Rogers Street, Cambridge, Massachusetts 02141 ("Sub-Subtenant,"
hereinafter also called "Tenant").

                              W I T N E S S E T H:

         WHEREAS, a lease dated January 16, 1998 (the "Prime Lease"), by and
between Robert L. Wolff, Jr., as Trustee of the 58 Charles Street Realty Trust
("Prime Landlord") as landlord and Cendant Operations, Inc. as Tenant, was
entered into for premises situated in Cambridge, MA, such premises being
commonly known as entire second floor, 58 Charles Street and more particularly
described in the Prime Lease (the "Premises"), a copy of which (with financial
terms deleted) is attached hereto as Exhibit A; and

         WHEREAS, a Sublease dated June 20, 2001 (the "Sublease"), by and
between CENDANT OPERATIONS, INC. ("Landlord" and "Sublandlord") as Sublandlord
and BIOPURE CORPORATION, the Sub-Sublandlord herein, as Tenant and Subtenant,
was entered into for premises situated in Cambridge, MA such premises being
commonly known as the entire second floor, 58 Charles Street and more
particularly described in the Sublease (the "Premises"), a copy of which (with
financial terms deleted) is attached hereto as Exhibit A-1; and

         WHEREAS, the parties hereto have agreed to enter into a sub-sublease of
all the Premises.

         NOW, THEREFORE, in consideration of the mutual promises and other good
and valuable consideration hereinafter contained, the parties hereto agree as
follows:

         1. (a) The Premises. Sub-Sublandlord does hereby sub-sublease to
Sub-Subtenant and Sub-Subtenant does hereby sub-sublease from Sub-Sublandlord
the Premises for the term, at the rental and upon all of the terms and
conditions set forth in this Sub-Sublease.

         (b) Parking. Pursuant to the Sublease, Sub-Sublandlord has the right to
use twenty-one (21) Parking Spaces in the building lot. Sub-Subtenant shall,
provided it is not in default under this Sub-Sublease, have the right to use ten
(10) such Parking Spaces upon occupancy and will pay the Sub-Sublandlord One
Hundred Twenty-Five and 00/100 ($125.00) Dollars per month for each such space.
The monthly fee for each of the ten (10) Parking Spaces shall be due and payable
to the Sub-Sublandlord in advance together with the Rent commencing on December
1, 2004 for the monthly parking fee and commencing on January 1, 2005 for the
Rent as provided in Section 2 herein. Sub-Sublandlord shall have the right to
sublease its remaining parking spaces to other users. So long as Sub-Sublandlord
has available Parking Spaces, in the event that Sub-Subtenant needs more
parking, Sub-Subtenant agrees to acquire the right to use additional space(s)
from the Sub-Sublandlord up to the number of spaces then available from the
Sub-Sublandlord. The monthly fee for any such additional Parking Spaces shall be
$125.00 per

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space and shall be due and payable in advance together with Rent. Sub-Subtenant
shall have no right to surrender Parking Spaces.

         2. Term. The term of this Sub-Sublease shall commence on the earlier of
(a) December 1, 2004 and (b) the date Sub-Subtenant takes possession of the
Premises (the "Commencement Date") and end on February 28, 2008, unless sooner
terminated as provided herein or in the Sublease or in the Prime Lease. The date
upon which Sub-Subtenant shall commence paying rent hereunder shall be January
1, 2005. If Sub-Sublandlord, for any reason whatsoever, cannot deliver
possession of the Premises to Sub-Subtenant on the Commencement Date, this
Sub-Sublease shall not be void or voidable, nor shall Sub-Sublandlord or its
agents be liable to Sub-Subtenant for any loss or damage resulting therefrom;
provided, however, that Sub-Subtenant shall not be liable for any rent until one
month after Sub-Sublandlord delivers possession of the Premises to
Sub-Subtenant. If Sub-Sublandlord tenders possession of the Premises to
Sub-Subtenant prior to the Commencement Date and Sub-Subtenant accepts such
possession, then the term of this Sub-Sublease and Sub-Subtenant's obligations
hereunder shall commence on the date that it accepts such possession. Except as
otherwise expressly set forth in this Section, any failure to deliver possession
on the Commencement Date, or delivery of possession prior thereto, shall not in
any way affect the obligations of Sub-Subtenant hereunder or the commencement or
expiration date of the term hereof.

         3. Rent.

         (a) Sub-Subtenant shall pay to Sub-Sublandlord as rent for the use and
occupancy of the Premises, without deduction, offset, prior notice or demand,
minimum annual rental equal to the following:

<TABLE>
<S>                          <C>               <C>                    <C>
Year 1                       $16.50/RSF        $226,000/year          $18,837.50/Month
Year 2                       $17.75/RSF        $243,175/year          $20,264.58/Month
Year 3 - Sub-                $20.00/RSF        $274,000/year          $22,833.33/Month
Sublease End Date
</TABLE>

         (b) Rent shall be paid in lawful money of the United States of America
to Sub-Sublandlord, in equal monthly installments as set forth above in advance,
on the first day of each calendar month ("Rent Payment Date") during the term of
this Sub-Sublease, to Biopure Corporation, 11 Hurley Street, Cambridge,
Massachusetts 02141, Attention, Francis H. Murphy, Chief Financial Officer, or
at such other address as Sub-Sublandlord may designate in writing. Should the
term of this Sub-Sublease begin or end on a day other than the first or last day
of a calendar month, all base rent and additional rent, payable hereunder shall
be adjusted and prorated on a per diem basis for any such months.

         4. Additional Rent. Contemporaneously with each monthly payment of
fixed rent pursuant to Article 3, Sub-Subtenant shall pay to Sub-Sublandlord the
annual parking fee. Commencing on the thirteenth (13th) month of the term and
thereafter contemporaneously with each monthly payment of fixed rent pursuant to
Article 3, Sub-Subtenant shall also pay to Sub-Sublandlord one-twelfth (1/12th)
of all additional rent, charges and fees of any nature payable by Landlord to
Prime Landlord under the Prime Lease or to Sublandlord under the Sublease in

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excess of the base year amounts as set forth below (including, without
limitation, Operating Expenses and Real Estate Taxes), payable by Landlord
pursuant to the Prime Lease or by Sublandlord pursuant to the Sublease, as the
same may be extended, modified or amended. The base year for Operating Expenses
shall be 2005 and the base year for Real Estate Taxes shall be fiscal year 2005.
Sub-Subtenant shall be fully responsible for the cost of additional services
(including, without limitation, after-hours HVAC service) requested by
Sub-Subtenant or provided by Prime Landlord to the Premises pursuant to Section
4.1.2 of the Prime Lease.

         5. Net Lease.

         (a) This Sub-Sublease shall be deemed and construed to be a net lease
and Sub-Subtenant shall accordingly pay to Sub-Sublandlord, absolutely net, the
rent free of any deductions or set-offs of any kind. Without limiting the
foregoing, Sub-Sublandlord has no obligation to Sub-Subtenant, whether before or
during, the term of this Sub-Sublease (a) to make any repairs, alterations,
additions, or changes to the Premises, including structural portions thereof,
(b) to comply with legal requirements or insurance requirements, (c) to insure
or protect the Premises or persons therein or about, (d) to furnish any
utilities, heat, water, air conditioning, power of any kind, or any other
services, or (e) to pay the real estate taxes, general or special assessments or
other taxes related to the use and operation of the Premises or related to any
accessory uses of the Premises. If there is any conflict between this Article 5
and any other provision of this Sub-Sublease or the Prime Lease or the Sublease,
then, as between Sub-Sublandlord and Sub-Subtenant is the obligations of the
Subtenant under the Sublease to Sublandlord (without in any way modifying the
obligations of the Tenant under the Prime Lease to Prime Landlord) or the
obligations of the Subtenant under the Sublease and as between Sublandlord and
Subtenant this Article 5 shall control.

         (b) Sub-Subtenant understands and acknowledges that (i) Sub-Sublandlord
shall not actually provide any of the services, make any of the repairs,
restoration or maintenance or take any of the actions that Prime Landlord or
Sublandlord has agreed to provide, to make, to take or to cause to be provided
or made or taken under the provisions of the Prime Lease and the Sublease and
Sub-Subtenant shall rely upon, and shall look solely to, the Prime Landlord or
Sublandlord as the case may be, for the provision or making thereof and (ii)
Sub-Sublandlord is not making and shall not be responsible for any
representations whatsoever which Prime Landlord may have made to Sublandlord, as
Tenant, in the Prime Lease. Sub-Sublandlord shall cooperate with Sub-Subtenant
in obtaining services, repairs, restoration or maintenance from Prime Landlord
and the Sublandlord.

         6. Repairs and Maintenance. Sub-Subtenant shall at its sole cost and
expense, maintain and repair the Premises and the mechanical systems located in
the Premises in good order and condition to the extent required under the Prime
Lease and Sublease.

         7. Alterations. Sub-Subtenant shall not make or permit to be made any
alterations, additions or improvements (the "Alterations") to the Premises
without the prior written consent of Sub-Sublandlord, Sublandlord and Prime
Landlord which may be granted or withheld in their sole discretion. If
Sub-Subtenant shall desire to make any such Alteration, Sub-Subtenant shall
apply for the consent of Sub-Sublandlord, Sublandlord and Prime Landlord and
furnish complete plans and specifications for the desired Alterations and the
names of the construction

                                      - 3 -

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contractor(s) to be engaged by Sub-Subtenant. If Sub-Sublandlord, Sublandlord
and Prime Landlord shall have granted their consent, Sub-Subtenant may proceed
with any such approved Alterations subject to Sub-Subtenant fulfilling the
following conditions:

                  (i) Subsequent to obtaining the consent of Sub-Sublandlord,
Sublandlord and Prime Landlord and prior to commencement of construction of the
Alterations, Sub-Subtenant shall deliver to Sub-Sublandlord, Sublandlord and
Prime Landlord (a) the building permit and a copy of the executed construction
contract covering the Alterations and (b) certificates evidencing the existence
of workers' compensation insurance covering all persons employed for such work
and comprehensive general liability and property damage insurance naming
Sub-Sublandlord, Sublandlord, Prime Landlord, and Sub-Subtenant as insureds,
with coverage of at least $5,000,000 single limit.

                  (ii) All Alterations shall be performed at Sub-Subtenant's
sole cost and expense. Sub-Subtenant shall keep the Premises free and clear of
all liens for any work or material claimed to have been furnished to
Sub-Subtenant or to the Premises on Sub-Subtenant's behalf. Sub-Subtenant shall
discharge any mechanics lien filed against the Premises or the Building of which
the Premises forms a part within thirty (30) days of such filing. Sub-Subtenant
shall indemnify Sub-Sublandlord, Sublandlord and Prime Landlord for any and all
claims, costs and expenses incurred by Sub-Sublandlord, Sublandlord and/or Prime
Landlord in connection with any liens. If Sub-Subtenant fails to discharge such
lien, Sub-Sublandlord may, but shall not be obligated to, discharge such lien on
Sub-Subtenant's behalf without determining the validity of the same.

                  (iii) At Sub-Sublandlord's option, Sub-Subtenant shall
provide, at Sub-Subtenant's expense, such completion, performance and/or payment
bonds.

                  (iv) Any construction, alteration, maintenance, repair,
replacement, installation, removal or decoration undertaken by Sub-Subtenant in
connection with the Premises shall be completed in accordance with the plans and
specifications approved by Sub-Sublandlord, Sublandlord and Prime Landlord,
shall be carried out in a good, workmanlike and prompt manner, shall comply with
all applicable statutes, laws, ordinances, regulations, rules, orders and
requirements of the authorities having jurisdiction thereof, and shall be
subject to supervision by Sub-Sublandlord or its employees, agents or
contractors.

                  (v) If the Alterations which Sub-Subtenant causes to be
constructed result in Sub-Sublandlord, Sublandlord or Prime Landlord being
required to make any alterations and/or improvements to other portions of the
Building in order to comply with any applicable statutes, laws, ordinances,
regulations, rules, orders or requirements (e.g., ordinances intended to provide
full access to handicapped persons), then Sub-Subtenant shall reimburse
Sub-Sublandlord, Sublandlord and/or Prime Landlord, as the case may be, upon
demand for all costs and expenses incurred by Sub-Sublandlord, Sublandlord
and/or Prime Landlord, as the case may be, in making such alterations and/or
improvements.

                  (vi) Any Alterations made by Sub-Subtenant shall remain on and
be surrendered with the Premises upon the expiration or sooner termination of
the Term, except Sub-Subtenant shall upon demand by Sub-Sublandlord, Sublandlord
or Prime Landlord, at Sub-

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Subtenant's sole cost and expense, forthwith and with all due diligence remove
all or any portion of any Alterations made by Sub-Subtenant which are designated
by Sub-Sublandlord to be removed, and Sub-Subtenant shall forthwith and with all
due diligence, and at its sole cost and expense, repair and restore the Premises
to their original condition, reasonable wear and tear excepted. Prior to any
installation of Alterations, and upon written request therefor by Sub-Subtenant,
Sub-Sublandlord, Sublandlord or Prime Landlord shall notify Sub-Subtenant if
removal of Alterations will be required.

                  (vii) During the progress of any Alterations, Sub-Sublandlord,
Sublandlord and Prime Landlord shall have the right to inspect the Premises and
Sub-Subtenant shall afford Sub-Sublandlord, Sublandlord and Prime Landlord
access and the opportunity to respect, at all reasonable times.

         8. Utilities. Electricity for Sub-Subtenant's lights and plugs shall be
separately metered and are the sole responsibility of the Sub-Subtenant. By the
Commencement Date, Sub-Subtenant shall notify the local utility servicing the
Premises that all utilities, electric and water charges should be billed by such
utility directly to Sub-Subtenant. Sub-Subtenant shall, during the term of this
Sub-Sublease and at its expense, pay all utility bills payable by
Sub-Sublandlord as subtenant pursuant to the Sublease or by Sublandlord as
tenant pursuant to the Prime Lease. If Sub-Sublandlord shall receive a utility
bill directly from the local utility company after the Commencement Date and
prior to the time the utility meters shall be billed directly to Sub-Subtenant,
then, upon rendition by Sub-Sublandlord of such bill to Sub-Subtenant,
Sub-Subtenant shall promptly pay to Sub-Sublandlord such charges. If
Sub-Subtenant shall fail timely to pay all or any portion of its utility bills
when due and owing, Sub-Sublandlord may render payment to the utility for the
account of Sub-Subtenant and any such sums paid by Sub-Sublandlord, together
with Landlord's Costs (defined in Article 23) shall be additional rent and added
to the monthly base rent for the following month. The provisions of this Article
8 shall survive the expiration or earlier termination of this Sub-Sublease.

         9. Brokerage. Sub-Sublandlord and Sub-Subtenant warrant and represent
to each other that neither party has dealt with any broker for the procurement
of this Sub-Sublease, other than Spaulding & Slye Colliers International
("Sub-Sublandlord's Broker") and GVA Thompson Doyle Hennessey & Stevens
("Sub-Subtenant's Broker"). Each party shall defend, indemnify and hold harmless
the other party from any loss, cost or expense suffered or incurred and arising
out of a breach of the foregoing representation. Sub-Sublandlord agrees to pay a
commission to Sub-Sublandlord's Broker pursuant to separate agreement.
Sub-Sublandlord shall also pay a commission to Sub-Subtenant's Broker.

         10. Assignment and Subletting.

         (a) Sub-Subtenant may not assign this Sub-Sublease or further
sub-sublet all or any portion of the Premises without the prior written consent
of Sub-Sublandlord, Sublandlord and Prime Landlord (in accordance with the
provisions of the Sublease and the Prime Lease). Said consent shall not be
unreasonably withheld or delayed. In the event of any such assignment or
sub-subletting, Sub-Subtenant shall remain liable for all liabilities of tenant
and obligations required on its part to be performed under this Sub-Sublease. If
this Sub-Sublease is assigned, or if the Premises or any part thereof are
sub-sublet or occupied by anybody other than Sub-

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Subtenant, Sub-Sublandlord may, after default by Sub-Subtenant, collect rent
from the assignee, sub-subtenant or occupant, and apply the net amount collected
to the rental herein reserved or otherwise required to be paid, but no such
assignment, sub-subletting, occupancy or collection shall be deemed a waiver of
this covenant, or the acceptance of the assignee, sub-subtenant or occupant as
tenant, or a release of Sub-Subtenant from the further performance by
Sub-Subtenant of the covenants on the part of Sub-Subtenant herein contained.

         (b) If Sub-Subtenant is a corporation or a partnership, an assignment
within the meaning of this Article shall include any one or more sales or
transfers, direct or indirect, by operation of law or otherwise, or the creation
of a new stock or partnership interest, by which a majority interest of capital
stock or partnership interest, as the case may be, shall be vested in a party or
parties who are non-stockholders or non-partners as of the date of execution of
this Sub-Sublease. This Article shall not apply if Sub-Subtenant's capital stock
or partnership interest, as the case may be, is listed on a recognized security
exchange.

         11. Insurance/Subrogation Waiver.

         (a) At all times while this Sub-Sublease is in effect, Sub-Subtenant
agrees to maintain at its expense, with an insurance carrier satisfactory to
Sub-Sublandlord the insurance required to be maintained by Sub-Subtenant under
this Sub-Sublease, by Subtenant under the Sublease and by Tenant under the Prime
Lease and the following:

                  (i) Workers' Compensation and Employer's Liability. Workers'
Compensation insurance for statutory limits or a State certificate. Employer's
Liability coverage should have limits of not less than $500,000.

                  (ii) Liability Insurance.

                           1) Occurrence basis commercial general liability
insurance, including blanket contractual coverage, for personal injury and
property damage of not less than $1 'million combined single limit per
occurrence.

                           2) Automobile liability insurance covering all owned,
non-owned and hired vehicles, with limits of not less than $1 million combined
single limit per occurrence.

                           3) Excess insurance coverage with a combined single
limit of not less than $4 million per occurrence in excess of the underlying
liability insurance requirements set forth above.

                           4) Such other liability insurance as may be required
by Landlord.

                  (iii) Property Insurance.

                           1) Insurance covering the Sub-Subtenant's property,
equipment, and/or material against loss or damage by fire and the perils
commonly referred to as extended coverage, vandalism and malicious mischief, in
an amount not less than 90% of replacement cost of the property, equipment
and/or material.

                                      - 6 -

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                           2) Such other property insurance as may be required
by Sub-Sublandlord.

                  (iv) Additional Insurance Requirements.

                           1) Each insurance policy listed above (except
workers' compensation) must name Biopure Corporation, Cendant Operations, Inc.
and Prime Landlord as insureds under the policy (Additional Named Insureds). All
insurance policies shall be primary to any self-insurance or insurance policies
carried by Sub-Sublandlord, Sublandlord or Prime Landlord.

                           2) Sub-Subtenant agrees to furnish Sub-Sublandlord,
Sublandlord and Prime Landlord, (i) contemporaneously with Sub-Subtenant's
execution of this Sub-Sublease and on each anniversary of the Commencement Date,
with a certificate of insurance evidencing the insurance required by this
Section. Such certificate will provide that said insurance may not be canceled
or materially modified for any reason, including without limitation, non-payment
of premium, except upon at least thirty (30) days prior written notice to
Sub-Sublandlord, Biopure Corporation at 11 Hurley Street, Cambridge,
Massachusetts 02141, Attention: CFO and to Cendant Operations, Inc. 1 Campus
Drive, Parsippany, New Jersey 07054, Attention: Legal or to Sub-Sublandlord and
Sublandlord at such other address as Sub-Sublandlord or Sublandlord may
designate from time to time, in writing. Certificates evidencing the renewal of
such policy shall be delivered to Sub-Sublandlord, Sublandlord and Prime
Landlord no later than thirty (30) days prior to the expiration of such policy.
Sub-Subtenant shall be in material breach of this Sub-Sublease if any insurance
required hereunder is not procured or is canceled or materially modified. If at
any time Sub-Subtenant fails or neglects to maintain the insurance required
pursuant to this Sub-Sublease, Sub-Sublandlord may, at its option, but without
any obligation to do so, and in addition to Sub-Sublandlord's other remedies
hereunder, upon five (5) days prior written notice thereof, effect such
insurance as the agent of and at the expense of Sub-Subtenant, by taking out
policies in companies satisfactory to Sub-Sublandlord for a period not exceeding
one (1) year in any one policy. Such insurance shall be kept in force as long as
necessary to protect Sub-Sublandlord's interest. Sub-Sublandlord shall not be
limited in the proof of any damages which it may claim against Sub-Subtenant,
arising out of or by reason of Sub-Subtenant's failure to provide and keep in
force insurance as provided herein, to the amount of the insurance premium or
premiums not paid or incurred by Sub-Subtenant which would have been payable
upon such insurance. Sub-Sublandlord shall be entitled to recover as damages for
such breach the uninsured amount of any loss or damages and the costs and
expense of suit suffered or incurred during any period when Sub-Subtenant shall
have failed or neglected to provide such insurance. The cost of any such
insurance procured by Sub-Sublandlord shall be added to the monthly Rent for the
following month, and same shall be considered as part of the Rent, and
Sub-Sublandlord shall have the same rights and privileges for the collection
thereof as if same were Rent.

                           3) In the event of any loss or damage to the Premises
or any property, equipment, fixtures of Sub-Subtenant, Sub-Subtenant waives all
claims against the Sub-Sublandlord, Sublandlord and Prime Landlord for any such
loss or damage and Sub-Subtenant shall look only to any Insurance which it has
obtained to protect against such loss and Sub-Subtenant shall obtain, for each
policy of such insurance, provisions waiving any claim against Sub-Sublandlord,
Sublandlord and Prime Landlord for loss or damage.

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                  (v) All policies required herein shall be purchased from
insurers licensed in the state in which the Premises are located and shall be
rated in the most recent Best's Insurance Reports as having a minimum
policyholder's rating of "A-" and a financial category no lower than "VI" ($25
million to $50 million of adjusted policyholder's surplus).

         (b) Comprehensive General Liability Insurance, including contractual
liability insurance coverage insuring all of Sub-Subtenant's indemnity
obligations under this Sub-Sublease except for the indemnity contained in
Section 19(h), personal injury, completed operations and Fire Legal Liability
Insurance, which covers the Premises and Sub-Subtenant's operations. The policy
shall name Sub-Sublandlord, Sublandlord and Prime Landlord as additional
insureds for liability, for bodily injury, including death, and property damage,
personal injury and other covered loss. The insurance will be primary and not
excess, with a combined single limit of not less than One Million
($1,000,000.00) Dollars for bodily injury, including death, and property damage
for any one occurrence.

         (c) Noncontributory, "All-Risk" casualty insurance covering all
buildings and improvements located on the Premises and trade fixtures,
merchandise and other personal property of Sub-Subtenant from time to time in,
on or about the Premises, in an amount not less than one hundred (100%) percent
of their actual replacement cost from time to time. Such insurance shall be
primary and not excess and shall protect Sub-Subtenant from damage or other loss
caused by fire or other casualty or cause including sprinkler damage, vandalism
and malicious mischief.

         (d) Sub-Subtenant hereby waives any and all rights of recovery against
Sub-Sublandlord, Sublandlord and Prime Landlord and their respective
subsidiaries and affiliates, and their respective officers, directors,
stockholders, agents and employees relating to Premises or property damage and
any resulting business interruption losses, occurring on or arising out of the
use, maintenance or occupancy of the Premises, the Prime Lease Premises or the
Building whether or not such loss or damage is insured.

         (e) This property damage subrogation waiver will preclude the
assignment of any insurance claim by way of subrogation to any insurer.
Sub-Subtenant agrees to give immediately to each appropriate insurer written
notice, if required, of the terms of this waiver and, if necessary, have said
insurance policies properly endorsed to prevent the invalidation of the
insurance coverages by reason of this waiver, if required by the insurance
policies.

         (f) Sub-Subtenant shall indemnify Sub-Sublandlord, Sublandlord and
Prime Landlord against any loss or expense, including but not limited to
reasonable attorneys' fees, resulting from the failure to obtain such insurance
subrogation waiver. This subrogation waiver shall be in addition to, and not in
limitation or derogation of, any other waiver or release contained in this
Sub-Sublease.

         (g) The provisions of this Section will survive the termination or
earlier expiration of this Sub-Sublease.

                                      - 8 -

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         12. Subordination to Prime Lease.

         (a) This Sub-Sublease is subject and subordinate to the Sublease and to
the Prime Lease. If the Sublease or the Prime Lease is terminated for any cause
whatsoever (other than by reason of the willful default of Sub-Sublandlord with
respect to Sub-Sublandlord's obligations as tenant under the Sublease, during
the term of this Sub-Sublease), Sub-Subtenant shall promptly vacate and
surrender the Premises to Sublandlord or to Prime Landlord and this Sub-Sublease
shall terminate as of the date of termination of the Sublease or the Prime
Lease, and Sub-Sublandlord and Sublandlord shall have no liability and/or
obligation to Sub-Subtenant for the termination of this Sub-Sublease. This
Section shall be self-operative and no further instrument of subordination shall
be required. To confirm such subordination, Sub-Subtenant shall execute promptly
any certificate that Sublandlord or Prime Landlord may request. Sub-Sublandlord
shall make best efforts to provide Sub-Subtenant with a Subordination
Non-Disturbance and Attornment Agreement ("SNDA") from Sublandlord which
Sublandlord has agreed to provide.

         (b) With respect to repairs, replacements, restoration, services, and
the performance of any other obligations required to be performed by the Prime
Landlord under the Prime Lease, and with respect to any consent or approval
required to be obtained of the Prime Landlord under the Prime Lease, and
provided Sub-Subtenant is not in default hereunder, Sub-Sublandlord's or
Sublandlord's sole obligation with respect thereto, upon being requested in
writing by Sub-Subtenant, shall be to assign to Sub-Subtenant such rights as
Sub-Sublandlord or Sublandlord may have, whether under the Prime Lease or
otherwise, to require compliance by the Prime Landlord with all of the
provisions of the Prime Lease insofar as they affect the Premises or any part
thereof or the use or occupancy thereof and to seek the approval or consent of
the Prime Landlord as well as such rights and remedies as Sub-Sublandlord or
Sublandlord may have as a result of the Prime Landlord's failure or refusal to
comply with such provisions. Sub-Subtenant acknowledges and agrees that
Sub-Sublandlord shall not be liable to Sub-Subtenant with respect to any delay,
default or failure of the Prime Landlord in the performance by the latter of its
obligations and covenants under the Prime Lease unless such be due to acts or
misconduct of Sub-Sublandlord or Sublandlord and neither shall the Rent,
Additional Rent, and other charges hereunder abate nor shall any of the
obligations of Sub-Subtenant hereunder be affected by reason thereof and
Sub-Subtenant agrees to look solely to the Prime Landlord for the performance of
same.

         13. Consent of Prime Landlord and of Sublandlord. This Sub-Sublease
shall not be an effective, binding and enforceable agreement as between the
parties hereto until Prime Landlord and Sublandlord execute the consent form
attached to this Sub-Sublease and made a part hereof. Following Sub-Subtenant's
execution of this Sub-Sublease, Sub-Sublandlord shall request the written
consents of Sublandlord and of Prime Landlord to this Sub-Sublease. The
signatures of the Sublandlord and Prime Landlord on the consent form at the end
of this document shall constitute consent to the terms of this Sub-Sublease.
Sub-Sublandlord makes no representation with respect to obtaining the required
consents, and, in the event that Prime Landlord or Sublandlord notes that it
will not give such consent, Sub-Sublandlord will notify Sub-Subtenant and, upon
receipt of such notification by Sub-Sublandlord of the disapproval by
Sublandlord or Prime Landlord, this Sub-Sublease shall be deemed null and void
and without force or effect, and Sub-Sublandlord and Sub-Subtenant shall have no
further obligations or liabilities to the other with respect to this
Sub-Sublease. Whenever in this Sub-Sublease, Sub-

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Subtenant is required to obtain Sub-Sublandlord's consent or approval,
Sub-Subtenant understands that Sub-Sublandlord may be required to first obtain
the consent or approval of Sublandlord and/or Prime Landlord. If Sublandlord
and/or Prime Landlord shall refuse such consent or approval, Sub-Sublandlord
shall be released of any obligation to grant its consent or approval whether or
not Sublandlord's or Prime Landlord's refusal, in Sub-Subtenant's opinion, is
arbitrary or unreasonable.

         14. Use. Sub-Subtenant shall use the Premises solely for the general
office uses permitted by the Prime Lease, and for no other uses or purposes.

         15. Condition of Premises. Sub-Subtenant, immediately prior to the
Commencement Date of this Sub-Sublease, has inspected and examined the Premises
and knows of the condition of the Premises. Sub-Subtenant accepts the Premises
in its "as is" condition on the Commencement Date herein. The Premises is
equipped with a card access security system customizable for employee use of
Sub-Subtenant. Telecommunications equipment including TI cable and Cat 5 and all
phones and data are wired to the furniture systems currently installed in the
Premises. All furniture and telecommunications equipment located in the Premises
as of the Commencement Date (the "Existing Furniture") shall be deemed to be
available to Sub-Subtenant, on an as-is basis, without any representation or
warranty whatsoever from Sub-Sublandlord. At the expiration of the term of this
Sub-Sublease, provided that Sub-Subtenant is not in default hereunder,
Sub-Sublandlord's shall transfer its title (without warranty) to the Existing
Furniture to Sub-Subtenant without any additional charge therefor. Sub-Subtenant
acknowledges that Sub-Sublandlord has no obligation to incur any expense
whatsoever in connection with the preparation of the Premises for
Sub-Subtenant's occupancy thereof and that Sub-Sublandlord has not made any
representation or warranty as to the suitability of the Premises for the conduct
or proper zoning of Sub-Subtenant's business, or otherwise.

         16. End of Term; Surrender; Holdover.

         (a) On the expiration or termination of this Sub-Sublease,
Sub-Subtenant shall (1) surrender the Premises to Sub-Sublandlord broom clean,
in good order and condition, ordinary wear and tear excepted, (2) remove all of
its signs, all furniture (including the Existing Furniture) and trade fixtures
from the Premises, repair all damages caused thereby and restore the Premises to
the condition it was in prior to such installation and (3) surrender all keys
for the Premises. The provisions of this Article shall survive the expiration or
earlier termination of this Sub-Sublease.

         (b) Sub-Subtenant shall remove from the Premises on or prior to such
expiration or earlier termination such property situated thereon which is not
owned by Sub-Sublandlord, Sublandlord or Prime Landlord, and, at its sole cost
and expense, shall, on or prior to such expiration or earlier termination,
repair any damage caused by such removal. Such property not so removed shall
become the property of Sub-Sublandlord, which may thereafter cause such property
to be removed from the Premises and disposed of, but the cost of any such
removal and disposition as well as the cost of repairing any damage caused by
such removal shall be borne by Sub-Subtenant. Sub-Subtenant's obligation to
observe or perform the covenants of this Section shall survive the expiration or
early termination of this Sub-Sublease.

                                     - 10 -

<PAGE>

         (c) Sub-Subtenant acknowledges that possession of the Premises must be
surrendered to Sub-Sublandlord at the expiration or sooner termination of the
term of this Sub-Sublease. Sub-Subtenant agrees it shall indemnify and save
Sub-Sublandlord harmless against all costs, claims, loss or liability resulting
from delay by Sub-Subtenant in so surrendering the Premises, including, without
limitation, any claims made by any succeeding tenant founded on such delay and
any holdover rent and other damages payable by Sub-Sublandlord to Sublandlord or
Prime Landlord. The parties recognize and agree that the damage to
Sub-Sublandlord resulting from any failure by Sub-Subtenant to surrender
possession of the Premises on a timely basis as aforesaid will be extremely
substantial, will exceed the amount of Rent theretofore payable hereunder and
will be impossible of accurate measurement. Sub-Subtenant, therefore, agrees
that if possession of the Premises is not surrendered to Sub-Sublandlord on the
date of expiration or sooner termination of the Term of this Sub-Sublease, then
Tenant agrees to pay to Sub-Sublandlord as damages for each month and for each
portion of any month during which Sub-Subtenant holds over in the Premises after
expiration or termination of the Term of this Sub-Sublease, a sum equal to two
hundred percent (200%) of the Rent which was payable per month under this
Sub-Sublease during the last month of the Term of this Sub-Sublease, plus .
Nothing contained herein shall be deemed to authorize Sub-Subtenant to remain in
occupancy of the Premises after the expiration or termination of the Term of
this Sub-Sublease. The indemnity contained in this subparagraph shall survive
expiration or termination of this Sub-Sublease.

         17. Security Deposit.

         (a) Sub-Subtenant shall post with Sub-Sublandlord prior to the
Commencement Date of this Sub-Sublease, and maintain throughout the term hereof,
a security deposit in the amount equal to Forty Thousand Five Hundred
Twenty-Nine and 16/100 Dollars ($40,529.16) (the "Security Deposit") to insure
the full and faithful performance by Sub-Subtenant of all the terms, covenants
and conditions of this Sub-Sublease upon Sub-Subtenant's part to be performed.
No interest shall be paid on the Security Deposit and Sub-Sublandlord may
co-mingle the Security Deposit with other security deposits held by
Sub-Sublandlord. If, at any time during the term hereof, or the term as it may
be extended, Sub-Subtenant shall fail to perform any of its obligations under
this Sub-Sublease, Sub-Sublandlord may use, apply or retain the whole or any
part of the Security Deposit for the payment of (i) any rent or other sums of
money which Sub-Subtenant may not have paid when due, (ii) any sum expended by
Sub-Sublandlord on Sub-Subtenant's behalf in accordance with the provisions of
the Sub-Sublease, and/or (iii) any sum which Sub-Sublandlord may expend or be
required to expend by reason of Sub-Subtenant's default, including, without
limitation, any damage or deficiency in or from the reletting of the Premises.
The use, application or retention of the Security Deposit, or any portion
thereof, by Sub-Sublandlord shall not prevent Sub-Sublandlord from exercising
any other right or remedy provided by this Sub-Sublease or by law (it being
intended that Sub-Sublandlord shall not first be required to proceed against the
Security Deposit) and shall not operate as either liquidated damages or as a
limitation on any recovery to which Sub-Sublandlord may otherwise be entitled.
If any portion of the Security Deposit is used, applied or retained by
Sub-Sublandlord for the purposes set forth above, Sub-Subtenant agrees, upon
written demand therefor made by Sub-Sublandlord, to deposit cash with the
Sub-Sublandlord in an amount sufficient to restore the Security Deposit to its
original amount. If Sub-Subtenant shall fully and faithfully comply with all of
the provisions of this Sub-Sublease, the Security Deposit or any balance
thereof, shall be returned to Sub-Subtenant without interest after the
expiration of the term or upon any later date

                                     - 11 -

<PAGE>

after which Sub-Subtenant has vacated the Premises. In the absence of evidence
satisfactory to Sub-Sublandlord of any permitted assignment of the right to
receive the Security Deposit, Sub-Sublandlord shall return same to the original
Sub-Subtenant, regardless of one or more assignments of Sub-Subtenant's interest
in this Sub-Sublease. Upon the return of the Security Deposit, or the remaining
balance thereof, to the original Sub-Subtenant or any successor to the original
Sub-Subtenant, Sub-Sublandlord shall be completely relieved of liability with
respect to the Security Deposit.

         (b) In lieu of a cash security deposit, Sub-Subtenant may deliver to
Sub-Sublandlord a clean, irrevocable, unconditional, transferable, evergreen
Letter of Credit issued by and drawn upon any commercial bank which is a member
of the Federal Reserve and the Federal Deposit Insurance Corporation acceptable
to Sub-Sublandlord (hereinafter referred to as the "Issuing Bank") with offices
for banking purposes in the City of Cambridge and Commonwealth of Massachusetts,
which Letter of Credit shall have a term of not less than one year, be in form
and content satisfactory to Sub-Sublandlord, be for the account of
Sub-Sublandlord and be in the amount of $40,529.16. The Letter of Credit shall
provide that:

                  (i) The Issuing Bank shall pay to Sub-Sublandlord or its duly
authorized representative an amount up to the face amount of the Letter of
Credit upon presentation of only the Letter of Credit and a sight draft in the
amount to be drawn;

                  (ii) The Letter of Credit shall be deemed to be automatically
renewed, without amendment, for consecutive periods of one year each during the
Term of this Sub-Sublease, unless the Issuing Bank sends written notice
(hereinafter called the "Non-Renewal Notices") to Sub-Sublandlord by certified
or registered mail, return receipt requested, not less than sixty (60) days next
preceding the then expiration date of the Letter of Credit, that it elects not
to have such Letter of Credit renewed;

                  (iii) Sub-Sublandlord, after receipt of the Non-Renewal
Notice, shall have the right, exercisable by a sight draft, only, to receive the
moneys represented by the Letter of Credit unless Sub-Subtenant delivers to
Sub-Sublandlord a replacement Letter of Credit in the form and content set forth
above, prior to Sub-Sublandlord receiving said moneys (which moneys shall be
held by Sub-Sublandlord as a cash deposit pursuant to the terms of this Section
17 pending the replacement of such Letter of Credit); and

                  (iv) Upon an assignment of Sub-Sublandlord's leasehold
interest, the Letter of Credit shall be transferable by Sub-Sublandlord as
provided below.

         (c) In the event of an assignment of Sub-Sublandlord's leasehold
interest, Sub-Sublandlord shall have the right to transfer the cash security or
Letter of Credit, as the case may be, deposited hereunder to the vendee or
lessee, and Sub-Sublandlord shall thereupon be released by Sub-Subtenant from
all liability for the return of such cash security or Letter of Credit. In such
event, Sub-Subtenant agrees to look solely to the new Sub-Sublandlord for the
return of said cash security or Letter of Credit. It is agreed that the
provisions hereof shall apply to every transfer or assignment made of said cash
security or Letter of Credit to a new Sub-Sublandlord. Sub-Subtenant shall
execute such documents as may be necessary to accomplish such transfer or
assignment of the Letter of Credit.

                                     - 12 -

<PAGE>

         (d) Sub-Subtenant covenants that it will not assign or encumber, or
attempt to assign or encumber, the monies or Letter of Credit deposited
hereunder as security, and that neither Sub-Sublandlord not its successors or
assigns shall be bound by any such assignment, encumbrance, attempted
assignment, or attempted encumbrance.

         18. Compliance With Law. Sub-Subtenant shall, at Sub-Subtenant's sole
cost and expense, comply with all laws, ordinances, statutes, rules and
regulations affecting the Premises, including, without limitation, those
referenced in Article 18, below. Sub-Subtenant shall, at Sub-Subtenant's sole
cost and expense, cure any violations levied against the Premises by duly
constituted public authorities having jurisdiction thereof.

         19. Environmental.

         (a) Sub-Subtenant acknowledges that Sub-Sublandlord has made no
representations or warranties as to the environmental conditions of the
Premises. Sub-Subtenant shall be deemed to have accepted the Premises on an "as
is" basis.

         (b) Sub-Subtenant shall not commence operations at the Premises until
obtaining all required federal, state or municipal permits from governmental or
public authorities having jurisdiction over Sub-Subtenant's operations at the
Premises and Sub-Subtenant shall promptly furnish to the Sub-Sublandlord copies
of notices, reports correspondence, submissions, made by Sub-Subtenant to
federal, state or municipal environmental or health authorities. Sub-Subtenant
covenants it will operate the Premises in full compliance with Environmental
Laws throughout the term of the Sub-Sublease and shall not allow any Hazardous
Materials to be used, stored, generated or otherwise handled on the Premises
without the prior written consent of the Sub-Sublandlord.

         (c) The Sub-Subtenant further agrees to keep real or personal property
free and clear of any Environmental Liens.

         (d) Sub-Subtenant shall immediately orally notify Sub-Sublandlord,
Sublandlord and Prime Landlord of any Release of Hazardous Materials and forward
a written notice within twenty-four (24) hours. Sub-Subtenant shall also
promptly provide Sub-Sublandlord with written notice within ten (10) days of the
receipt of any (i) notice of violation of Environmental Laws; (ii) notice that
an Environmental Lien has been filed against the Premises; or (iii) commencement
of an Environmental Action or notice that an Environmental Action will be filed
in connection with the Premises.

         (e) Sub-Subtenant shall, at its own cost and expense, maintain the
Premises in good repair and shall have the responsibility for performing all
Remedial Actions which are necessary for addressing any Releases of Hazardous
Materials on the Premises occurring from and after the Commencement Date. All
Remedial Actions conducted by the Sub-Subtenant shall be performed in accordance
with the requirements of applicable Environmental Laws.

         (f) If Sub-Subtenant fails to immediately undertake such Remedial
Action, Sub-Sublandlord shall have the right but not the obligation to enter
onto the Premises and to take such Remedial Action as it deems necessary to
eliminate or minimize said Release. All costs and expenses incurred by
Sub-Sublandlord in the exercise of such rights shall be deemed to be

                                     - 13 -

<PAGE>

additional rent hereunder and shall be payable by Sub-Subtenant to
Sub-Sublandlord upon demand.

         (g) Sub-Subtenant shall permit Sub-Sublandlord and Sub-Sublandlord's
agents employees and contractors, access to the Premises to conduct
environmental testing and to collect samplings from time-to-time during regular
business hours, or during other hours, if necessary, to abate a Release.
Sub-Sublandlord agrees to use its reasonable efforts to avoid materially and
unreasonably interfering with Sub-Subtenant's use of the Premises during the
conduct of inspection and shall restore the affected areas of the Premises to
its approximate pre-inspection condition upon completion of environmental
investigation.

         (h) Sub-Subtenant hereby agrees to defend, indemnify, and hold harmless
the Sub-Sublandlord from and against any Environmental Liabilities arising out
of any of the following which occur from and after the Commencement Date: (i)
any Release or threatened Release of Hazardous Materials at or from the
Premises, (ii) any violations of Environmental Laws; (iii) any Environmental
Actions; (iv) any personal injury (including wrongful death) or property damage
(real or personal) arising out of exposure to Hazardous Materials used, handled,
generated, transported or disposed at the Premises and (v) any breach of any
warranty or representation or covenant regarding environmental matters made by
the Sub-Subtenant. This environmental indemnity shall survive the termination of
the Sub-Sublease.

         (i) For the purposes of this section, the following definitions will
apply:

                  "Environmental Actions" refers to any complaint, summons,
citation, notice, directive order, claim, litigation, investigation, judicial or
administrative proceeding, judgment, letter or other communication from any
Governmental Authority or any third party involving violations of Environmental
Laws or Releases of Hazardous Materials from the Premises.

                  "Environmental Laws" includes the Comprehensive Environmental
Response, Compensation and Liability Act ("CERCLA"), 42 U.S.C. 9601 et. seq., as
amended; the Resource Conservation and Recovery Act of ("RCRA"), 42 U.S.C. 6901
et. seq., as amended; the Clean Air Act ("CAA"), 42 U.S.C. 7401 et seq., as
amended; the Clean Water Act ("CWA"), 33 U.S.C. 1251 et. seq., as amended; the
Occupational Safety and Health Act ("OSHA"), 29 U.S.C. 655 et. seq., and any
other federal, state, local or municipal laws, statutes, regulations, rules or
ordinances imposing liability or establishing standards of conduct for
protection of the environment.

                  "Environmental Lien" means any lien, security interest, charge
or other encumbrance for Environmental Liabilities and Costs incurred by a
Government Authority.

                  "Environmental Liabilities" means any monetary obligations,
losses, liabilities (including strict liability), damages, punitive damages,
consequential damages, treble damages, costs and expenses (including all
reasonable out-of-pocket fees, disbursements and expenses of counsel,
out-of-pocket expert and consulting fees and out-of-pocket costs for
environmental site assessments, remedial investigation and feasibility studies),
fines, penalties, sanctions and interest incurred as a result of any
Environmental Action filed by any governmental authority or any third party
which relate to any violations of Environmental Laws, Environmental Actions,

                                     - 14 -

<PAGE>

Remedial Actions, Releases or threatened Releases of Hazardous Materials from or
onto the Premises.

                  "Hazardous Materials" shall include any element, compound, or
chemical that is defined, listed or otherwise classified as a contaminant,
pollutant, toxic pollutant, toxic or hazardous substances, extremely hazardous
substance or chemical, hazardous waste, special waste, or solid waste under
Environmental Laws; petroleum and its refined products; polychlorinated
biphenyls; any substance exhibiting a hazardous water characteristic, including
but not limited to, corrosivity, ignitability, toxicity or reactivity as well as
any radioactive or explosive materials; and any raw materials, building
components, including but not limited to, asbestos-containing materials and
manufactured products containing hazardous substances.

                  "Release" means any spilling, leaking, pumping, emitting,
emptying, discharging, injecting, escaping, leaching, dumping, or disposing
(including the abandonment or discarding of barrels, containers or other closed
receptacles containing Hazardous Materials) of Hazardous Materials into the
environment.

                  "Remedial Action" means all actions taken to clean up, remove,
remediate, contain, treat, monitor, assess, evaluate or in any other way address
Hazardous Materials in the indoor or outdoor environment; prevent or minimize a
Release or threatened Release of Hazardous Materials so they do not migrate,
endanger or threaten to endanger public health or welfare or the indoor or
outdoor environment; perform pre-remedial studies and investigations and
post-remedial operation and maintenance activities; or any other actions
authorized by 42 U.S.C. 9601.

         20. Indemnification. Sub-Subtenant shall protect, indemnify, defend
(with counsel acceptable to Sub-Sublandlord) and save harmless Sub-Sublandlord,
Sublandlord and Prime Landlord and their respective officers, directors,
employees, agents, licensees, invitees and assigns (each an "Indemnified Party")
from and against all liabilities, obligations, losses, claims, damages,
penalties, actions, suits, costs, charges, subrogation and expenses (including,
without limitation, fees and expenses of legal counsel and expert witnesses and
court costs) (collectively, "Damages") imposed upon or incurred by or asserted
against any Indemnified Party or against the Premises arising out of, or in any
manner connected with the actual or alleged (a) use of the Premises by
Sub-Subtenant, its agents, employees, invitees, licensees or contractors
(collectively, "Sub-Subtenant's Agents"); (b) any failure on the part of
Sub-Subtenant to perform or comply with any of the terms of this Sub-Sublease;
(c) performance of any labor or services or the furnishing of any materials or
other property in respect of the Premises or any part thereof; (d) any act or
failure to act on the part of Sub-Subtenant or Sub-Subtenant's Agents in or
about the Premises. In case any action, suit or proceeding is brought against
any Indemnified Party by reason of any occurrence referred to above,
Sub-Subtenant, upon the request of such Indemnified Party, will at
Sub-Subtenant's expense, resist and defend such action, suit or proceeding or
cause the same to be resisted and defended by counsel designated by
Sub-Subtenant and acceptable to the Indemnified Party. The foregoing agreement
to indemnify and hold each Indemnified Party harmless shall not be applicable to
the extent that such Damages are caused by the willful misconduct or sole
negligence of an Indemnified Party. This indemnity shall survive the expiration
or earlier termination of this Sub-Sublease.

                                     - 15 -

<PAGE>

         21. Default by Sub-Subtenant. Any of the following events shall be
deemed to be events of default under this Sub-Sublease:

         (a) Failure of Sub-Subtenant to pay any installment of the Base Rent,
Additional Rent or other sum payable to Sub-Sublandlord hereunder on the date
that same is due and the same continues for three (3) days after written notice
from Sub-Sublandlord thereof.

         (b) Failure of Sub-Subtenant to comply with any term, condition or
covenant of this Sub-Sublease, the Sublease or the Prime Lease, other than the
payment of Base Rent, Additional Rent or other sum of money and Sub-Subtenant
shall fail to remedy the same within ten (10) days after prior written notice to
Sub-Subtenant specifying such failure, or if such failure is of such a nature
that Sub-Subtenant cannot reasonably remedy the same within such ten (10) day
period, Sub-Subtenant shall fail to commence promptly to remedy the same and to
prosecute such remedy to completion with diligence and continuity, provided that
such cure is effected within thirty (30) days after such prior written notice.

         (c) The making by Sub-Subtenant of an assignment for the benefit of
creditors, or its admitting in writing its inability to pay its debts as they
mature, or its adjudication as a bankrupt, or its filing of a petition in
voluntary bankruptcy of a petition or answer seeking reorganization or an
arrangement with creditors under the federal bankruptcy laws or any other
similar law or statute of the United States or any state, or its filing of a
petition to take advantage of any debtor's or insolvency act.

         (d) Filing of a petition under any section or chapter of the National
Bankruptcy Act, as amended, or under any similar law or statute of the United
States or any State thereof by Sub-Subtenant or any guarantor of Sub-Subtenant's
obligations or adjudication as a bankrupt or insolvent in proceedings filed
against Sub-Subtenant or such guarantor.

         (e) Appointment of a receiver or trustee for all or substantially all
of the assets of Sub-Subtenant or any guarantor of Sub-Subtenant's obligation
hereunder.

         22. Remedies of Sub-Sublandlord.

         (a) Upon the occurrence of any of the events of default listed in
Article 21, Sub-Sublandlord shall have the option to pursue any remedy available
to Sublandlord as landlord under the Sublease or to Prime Landlord as landlord
under the Prime Lease or any one or more of the following remedies, without any
notice or demand whatsoever:

                  (i) Terminate this Sub-Sublease, in which event Sub-Subtenant
shall immediately surrender the Premises to Sub-Sublandlord. If Sub-Subtenant
fails to so surrender the Premises, Sub-Sublandlord may, without prejudice to
any other remedy which it may have for possession of the Premises or arrearages
in rent, enter upon and take possession of the Premises and expel or remove
Sub-Subtenant and any other person who may be occupying such Premises or any
part thereof, by force if necessary, without being liable for prosecution or any
claim for damages therefor.

                  (ii) Enter upon and take possession of Premises, by force if
necessary, without terminating this Sub-Sublease and without being liable for
prosecution or for any claim for

                                     - 16 -

<PAGE>

damages therefor, and expel or remove Sub-Subtenant and any other person who may
be occupying such Premises or any part thereof. Sub-Sublandlord may relet the
Premises and receive the rent therefor. Sub-Subtenant agrees to pay to
Sub-Sublandlord monthly or on demand from time to time any deficiency that may
arise by reason of any such reletting. In determining the amount of such
deficiency, the brokerage commission, attorneys' fees, remodeling expenses and
other costs incurred by Sub-Sublandlord in connection with such reletting shall
be subtracted from the amount of rent received under such reletting.

                  (iii) Enter upon the Premises, by force, if necessary, without
terminating this Sub-Sublease and without being liable for any prosecution or
for any claim for damages therefor, and do whatever Sub-Subtenant is obligated
to do under the terms of this Sub-Sublease. Sub-Subtenant agrees to pay
Sub-Sublandlord on demand for Sub-Sublandlord's Costs (defined in Article 23) in
effecting compliance with Sub-Subtenant's obligations under this Sub-Sublease.
Sub-Sublandlord shall not be liable for any damages resulting to the
Sub-Subtenant from such action, whether caused by negligence of Sub-Sublandlord
or otherwise.

         (b) If Sub-Sublandlord elects to terminate this Sub-Sublease by reason
of an event of default, Sub-Sublandlord may accelerate all Base Rent, Additional
Rent and other charges required to be paid by Sub-Subtenant under this
Sub-Sublease.

         (c) In case of any event of default or breach by Sub-Subtenant, or
threatened or anticipatory breach or default, Sub-Subtenant shall also be liable
for and shall pay on demand to Sub-Sublandlord (in addition to any sum required
to be paid by Sub-Subtenant under this Sub-Sublease): the amount of all loss and
damage which Sub-Sublandlord may suffer by reason of such default, breach or
threatened default or breach; brokers' fees incurred by Sub-Sublandlord in
connection with reletting the whole or any part of the Premises; the costs of
removing and storing Sub-Subtenant's or any other occupant's property; the
reasonable costs of repairing, altering, remodeling or otherwise putting the
Premises into condition reasonably acceptable to a new tenant or tenants; any
rent concessions given to a new tenant; all expenses incurred by Sub-Sublandlord
in enforcing or defending Sub-Sublandlord's rights and/or remedies, including
attorneys' fees; and the amount of any rent concession, free rent or leasehold
improvement allowance given to Sub-Subtenant in this Sub-Sublease and any
brokerage fee or concession paid by Sub-Sublandlord under this Sub-Sublease.

         (d) All Base Rent and Additional Rent shall bear interest from the date
due until the date paid at the rate equal to the Bank of America "prime rate"
plus 3% per annum, not to exceed the maximum rate allowable by law.

         (e) All rights and remedies of Sub-Sublandlord herein enumerated shall
be cumulative and none shall exclude any other right or remedy allowed by law or
equity. For the purposes of any suit brought or based hereon, this Sub-Sublease
shall be construed to be a divisible contract, to the end that successive
actions may be maintained on this Sub-Sublease on successive periodic sums which
mature hereunder. Sub-Subtenant shall pay, upon demand, all of Sub-Sublandlord's
costs, charges and expenses, including, without limitation, the fees of counsel,
agents and others retained by Sub-Sublandlord and incurred in enforcing
Sub-Subtenant's obligations hereunder or under a hold over tenancy or incurred
by Sub-Sublandlord in any

                                     - 17 -

<PAGE>

litigation, negotiations or transactions in which Sub-Subtenant causes
Sub-Sublandlord, without Sub-Sublandlord's fault, to become involved or
concerned.

         23. Right of Sub-Sublandlord to Perform Sub-Subtenant's Covenants:
Inspections. If Sub-Subtenant shall fail to make any payment or perform any act
required to be made or performed by it hereunder, without being under any
obligation to do so and without thereby waiving such default, Sub-Sublandlord
may at any time thereafter make such payment or perform such act for the account
and at the expense of Sub-Subtenant, and may enter upon the Premises or any part
thereof for such purpose and take all such action thereon as may be necessary or
appropriate therefor. No such entry shall constitute an eviction of
Sub-Subtenant. All payments so made by Sub-Sublandlord, together with all other
costs, expenses, legal fees and disbursements incurred by Sub-Sublandlord in
taking such remedial action (collectively, "Sub-Sublandlord's Costs"), shall
constitute additional rent due hereunder payable by Sub-Subtenant upon demand.
The provisions of this Article 23 shall survive the termination or early
expiration of this Sub-Sublease.

         24. Late Charge. If Sub-Subtenant fails to pay any Base Rent or
Additional Rent when due, to help defray the additional cost to Sub-Sublandlord
for processing such late payments, Sub-Subtenant shall pay to Sub-Sublandlord on
demand a late charge equal to two (2%) percent of such installment. Such amount
if not received within five (5) days shall also bear interest as provided in
Section 22(d). Sub-Subtenant's failure to pay such amount shall be a material
breach of this Sub-Sublease. The provision for such late charge shall be in
addition to all of Sub-Sublandlord's other rights and remedies hereunder, at law
or equity and shall not be construed as liquidated damages.

         At no time shall Sub-Subtenant be obligated or required to make any
interest payment with respect to late fees or defaulted Rent payments at a rate
which could subject Sub-Sublandlord to either civil or criminal liability as a
result of being in excess of the maximum rate which Sub-Subtenant is permitted
by law to contract or agree to pay. If by the terms of this Sub-Sublease,
Sub-Subtenant is at any time required or obligated to pay interest arising out
of late payment fees or defaulted rent payments at a rate in excess of such
maximum rate, the rate of interest under this Sub-Sublease shall be deemed to be
immediately reduced to such maximum rate and interest payable hereunder shall be
computed at such maximum rate and the portion of all prior interest payments in
excess of such maximum rate shall be applied and shall be deemed to have been
payments in reduction of rent due hereunder.

         25. Compliance With Terms of Prime Lease: Incorporation by Reference.

         (a) The terms, conditions and respective obligations of Sub-Sublandlord
and Sub-Subtenant to each other under this Sub-Sublease shall be the terms and
conditions of the Sublease (including the incorporated provisions of the Prime
Lease), except for (i) those provisions of the Sublease which are directly
contradicted by this Sub-Sublease and (ii) the Excluded Provisions of the
Sublease (as defined below), in which event, as between Sub-Sublandlord and
Sub-Subtenant only, the terms of this Sub-Sublease shall control over the
Sublease. Therefore, for the purposes of this Sub-Sublease, wherever in the
Sublease the word "Tenant" is used it shall be deemed to mean the Sub-Subtenant
herein and wherever the word "Landlord" is used it shall be deemed to mean the
Sub-Sublandlord herein.

                                     - 18 -

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         (b) The parties agree that for purposes of incorporating the terms of
the Sublease into this Sub-Sublease, Excluded Provisions of the Sublease (as
defined below) shall only apply to the landlord-tenant relationship between
Sublandlord and Sub-Sublandlord and shall not apply to the landlord-tenant
relationship between Sub-Sublandlord and Sub-Subtenant and shall not be part of
this Sub-Sublease. The foregoing shall not release or impair any obligation of
Sublandlord under the Sublease or Prime Landlord under the Prime Lease.
Sub-Sublandlord shall cooperate with Sub-Subtenant and use commercially
reasonable efforts to cause Prime Landlord to perform its obligations under the
Prime Lease and to cause Sublandlord to perform its obligations under the
Sublease. As used herein, the "Excluded Provisions of the Sublease" shall mean:
Sections 1(b); 2; 3; 4; 9; 17; 26; 33; and 36.

         (c) During the term of this Sub-Sublease and for all periods subsequent
for obligations which have arisen prior to the termination of this Sub-Sublease,
Sub-Subtenant does hereby expressly assume and agree to perform and comply with,
for the benefit of Sub-Sublandlord, Sublandlord and Prime Landlord, each and
every obligation of Sub-Sublandlord under the Sublease, except for the
obligation to pay rent to Sublandlord under the Sublease. Sub-Subtenant shall
not commit or suffer any act or omission that will violate any of the provisions
of the Sublease or the Prime Lease.

         (d) Except as provided herein, in all provisions of the Sublease
requiring the approval or consent of Sublandlord or Prime Landlord,
Sub-Subtenant shall be required to obtain the approval or consent of Prime
Landlord, Sublandlord and Sub-Sublandlord. Wherever in this Sub-Sublease
Sub-Sublandlord's consent or approval is required, if Sub-Sublandlord shall
delay or refuse such consent or approval, Sub-Subtenant in no event shall be
entitled to make, nor shall Sub-Subtenant make, any claim, and Sub-Subtenant
hereby waives any claim for money damages (nor shall Sub-Subtenant claim any
money damages by way of set-off, counterclaim or defense) based upon any claim
or assertion by Sub-Subtenant that Sub-Sublandlord unreasonably withheld or
unreasonably delayed its consent or approval. Sub-Subtenant's sole remedy shall
be an action or proceeding to enforce any such provision, for specific
performance, injunction or declaratory judgment.

         (e) Wherever notices are required in the Sublease to be given to Prime
Landlord or Sublandlord, Sub-Subtenant shall be required to give notice to
Sub-Sublandlord at least an additional five (5) days in advance of the time
required under the Sublease. Whenever in the Sublease defaults by
Sub-Sublandlord are required to be cured or acted upon by Sub-Sublandlord within
a specified period of time, Sub-Subtenant shall perform such act and cure such
default at least five (5) days prior to the time required for such performance
or cure under the Sublease.

         (f) Sub-Subtenant shall give to Sub-Sublandlord a copy of all notices
given to Prime Landlord or Sublandlord in the same manner and simultaneous with
such notices given to Prime Landlord or Sublandlord, as the case may be.
Sub-Subtenant shall promptly give to Sub-Sublandlord a copy of all notices
received from Prime Landlord or Sublandlord.

         (g) Each of Sub-Sublandlord and Sub-Subtenant agrees that it shall not
cause any default on the part of Sub-Sublandlord under the Sublease.
Sub-Subtenant does hereby indemnify and agree to hold Sub-Sublandlord harmless
from any claims, loss, damages, or liability (including attorneys' fees) arising
out of or in connection with the failure of Sub-

                                     - 19 -

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Subtenant to perform any of the terms or provisions contained in the Sublease
which, by the terms of this Sub-Sublease, Sub-Subtenant is obligated to perform.
Sub-Sublandlord hereby indemnifies and agrees to hold Sub-Subtenant harmless for
any claims, loss, damages or liability including attorneys' fees arising out of
or in connection with the failure of Sub-Sublandlord to perform any of the terms
or provisions in the Sublease which (a) by the terms of this Sub-Sublease
Sub-Subtenant is not obligated to perform or (b) Sub-Subtenant has timely
performed pursuant to this Sub-Sublease. This Section shall survive termination
or expiration of the term of this Sub-Sublease.

         26. Notices. Any notice, approval, consent or other communications
permitted or required under this Sub-Sublease shall be effective, if hand
delivered, upon receipt, and otherwise as provided for herein, only if in
writing and given by hand delivery or by mailing by certified or registered
mail, postage prepaid, return receipt requested, or by nationally recognized
overnight air courier, to the address of the party set forth below or to such
other addresses as the party to be notified may from time to time designate by
notice given in the manner provided in this Article. Notices shall be deemed
effective upon receipt, if hand delivered, or upon deposit with nationally
recognized overnight air courier, or deposit in the United States mail. Notices
from Sub-Sublandlord may be given by Sub-Sublandlord's attorney.

             If to Landlord/Sublandlord:      CENDANT OPERATIONS, INC.
                                              1 Campus Drive
                                              Parsippany, New Jersey 07054
                                              Attention: Legal

             If to Sub-Sublandlord/Subtenant: BIOPURE CORPORATION
                                              11 Hurley Street
                                              Cambridge, MA 02141
                                              Attention: Chief Financial Officer

             If to Prime Landlord:            58 Charles Street Realty Trust
                                              c/o The Cambridge Co.
                                              300 Massachusetts Avenue
                                              Boston, MA 02115

             If to Sub-Subtenant:             SENIOR WHOLE HEALTH, LLC
                                              101 Rogers Street
                                              Cambridge, MA 02141
                                              Attention: Matthias Vinikas

         27. Successors and Assigns. The covenants, conditions and agreements
contained in this Sub-Sublease shall bind and inure to the benefit of the
parties hereto and their respective heirs, executors, administrators, legal
representatives, successors and assigns, except as expressly hereinbefore
otherwise provided. If "Sub-Subtenant" consists of more than one person or
party, the obligations and liabilities of each such person or party shall be
joint and several.

         28. Excluded Signage. Sub-Subtenant shall have no right to use, display
or exhibit any signage which has any "Cendant or NetMarket or BIOPURE" insignia,
logo, facsimile or

                                     - 20 -

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trademark thereon. Sub-Sublandlord shall have the right, either before or during
the term of this Sub-Sublease to enter upon the Premises and remove same.

         29. Inspections. Sub-Sublandlord and its representatives may enter the
Premises or any part thereof upon advance notice, except in the event of an
emergency for which no advance notice is necessary, for the purpose of (i)
inspecting the same or for the purpose of doing any work Sub-Sublandlord shall
be required or permitted to do under this Sub-Sublease, and taking all such
action thereon as may be reasonably necessary or appropriate for any such
purpose and (ii) displaying thereon advertisements for sale or letting at any
time after Sub-Subtenant shall have vacated or abandoned the Property.
Sub-Sublandlord shall not have any duty to make any such inspection and shall
not incur any liability or obligation for not making any such Inspection. No
such entry in accordance with the foregoing shall constitute an eviction of
Sub-Subtenant. Sub-Sublandlord and its representatives shall also have the
right, during the last three (3) months of the term, to enter the Premises to
show same to other(s) and shall have the right to erect a "For Rent" sign on the
Property.

         30. Captions. The captions inserted herein are inserted only as a
matter of convenience for reference and in no way define the scope of this
Sub-Sublease or the intent of any provision hereof.

         31. No Offer. This Sub-Sublease shall not be deemed to be an offer and
shall in no event be binding upon Sub-Sublandlord until duly executed by an
authorized officer thereof and delivered to Sub-Subtenant by an authorized
representative of the Sub-Sublandlord.

         32. Rent Tax. Sub-Subtenant shall pay any tax assessed by the State in
which the Premises are located that are applicable to rentals or charges
specified in this Sub-Sublease.

         32. Early Termination Right. By offering their consent to this
Sub-Sublease, both Prime Landlord and the Sublandlord acknowledge and affirm
that the Early Termination Right available to the Sublandlord under the Prime
Lease has not been exercised.

         33. Sub-Sublandlord's Representations and Warranties. Sub-Sublandlord
hereby represents and warrants that (a) the Prime Lease attached hereto as
Exhibit A has not been amended and is the entire agreement between Landlord and
Prime Landlord; (b) the Prime Lease documents are in full force and effect; (c)
no outstanding uncured notices of default or termination exist and no notices of
default have issued under the Prime Lease; (d) Sub-Sublandlord will not amend
the Prime Lease voluntarily if such amendment would adversely affect the
Sub-Subtenant's rights under the Sub-Sublease, increase the Sub-Subtenant's
obligations under the Sub-Sublease, decrease the size of the Premises, or
shorten the term of the Sub-Sublease; and (e) Sub-Sublandlord shall request a
recognition agreement from the Prime Landlord stating that if the Prime Lease
terminates, the Prime Landlord will recognize Sub-Subtenant as a direct tenant.

         34. Access. Sub-Subtenant shall have twenty-four (24) hour per day,
seven (7) day per week access to the Premises and parking.

                                     - 21 -

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         35. Signage. Sub-Subtenant shall have signage in the lobby directory of
the building and on the Sub-Subtenant's main entrance door, with the prior
consent of the Sub-Sublandlord, Sublandlord and Prime Landlord with respect to
such main entrance door signage.

         IN WITNESS WHEREOF, the parties hereto have duly signed, sealed and
delivered this instrument, as of the day and year first above set forth.

                                 SUB-SUBLANDLORD

                                 BIOPURE CORPORATION

                                 By: /s/ Francis H. Murphy
                                     ----------------------------------------
                                 Name: Francis H. Murphy
                                 Title: Chief Financial Officer

                                 SUB-SUBTENANT

                                 SENIOR WHOLE HEALTH, LLC

                                 By: /s/ Matthias J. Vinikas
                                     ----------------------------------------
                                 Name: Matthias J. Vinikas
                                 Title: Chief Operating Officer

                                     - 22 -

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