Exhibit 10.1

THIRD AMENDMENT TO LEASE

This THIRD AMENDMENT TO LEASE dated as of March 23, 2001 (this “Amendment”)
between RCPI TRUST, a Delaware business trust having an office c/o Tishman
Speyer Properties, L.P., 45 Rockefeller Plaza, New York, New York 10111
(“Landlord”), and ANTIGENICS, INC., a Delaware corporation having an office at
630 Fifth Avenue, New York, New York 10111 (“Tenant”).

WITNESSETH:

WHEREAS, Landlord’s predecessor-in-interest, Rockefeller Center Properties, and
Tenant’s predecessor-in-interest, GHA Management Corporation, entered into that
certain Lease dated December 6, 1995 (the “Original Lease”), as assigned by GHA
Management Corporation to Tenant pursuant to that certain Assignment of Lease
dated as of January 3, 2000, which Assignment of Lease was consented to by
Landlord pursuant to that certain Consent to Assignment dated as of August 24,
2000, and as amended by (i) First Amendment to Lease, dated as of October 23,
1996 (the “First Amendment to Lease”), and (ii) Second Amendment to Lease, dated
as of February 25, 2000 (the “Second Amendment to Lease”) (as amended by the
First Amendment to Lease and the Second Amendment to Lease, the “Original
Lease”), covering a portion of the 16th floor and a portion of the 21st floor
(the “Original Premises”) of the building located at 630 Fifth Avenue, New York,
New York (the “Building”), all as more particularly described in the Original
Lease; and

WHEREAS, Landlord and Tenant desire to modify the Original Lease to (i) provide
for the leasing by Tenant of a portion of the 22nd floor of the Building,
designated as Space ‘C’, and being more particularly shown on Exhibit A attached
hereto (the “Third Additional Premises”), and (ii) otherwise modify the terms
and conditions of the Original Lease, all as hereinafter set forth (the Original
Lease, as modified by this Amendment, the “Lease”).

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

1. Capitalized Terms. All capitalized terms used and not otherwise defined in
this Amendment shall have the respective meanings ascribed to them in the
Original Lease.

2. Lease of Third Additional Premises. (a) Landlord hereby leases to Tenant, and
Tenant hereby leases from Landlord, subject and subordinate to the Qualified
Encumbrances, the Third Additional Premises for a term commencing on the date
that Landlord delivers possession of the Third Additional Premises to Tenant
free of all tenancies and occupants (the “Third Additional Premises Commencement
Date”) (provided, however, Tenant shall not be required to accept possession of
the Third Additional Premises prior to March 19, 2001) and ending on
December 31, 2006 (the “Third Additional Premises Expiration Date”), or such
earlier date upon which the term of the Lease may expire or be terminated
pursuant to any of the conditions of limitation or other provisions of the Lease
or pursuant to law, upon all of the terms and conditions of the Original Lease,
as modified by this Amendment.

(b) Landlord shall deliver possession of the Third Additional Premises to Tenant
on the Third Additional Premises Commencement Date by giving Tenant notice that
the Third Additional Premises are vacant and available for Tenant’s occupancy.
Landlord shall not be liable for failure to deliver possession of the Third
Additional Premises to Tenant on any specified date, and such failure shall not
impair the validity of this Amendment. There shall be no postponement of the
Third Additional Premises Commencement Date for any delay in the delivery of
possession of the Third Additional Premises to Tenant that results from any
Tenant Delay. The provisions of this paragraph are intended to constitute “an
express provision to the contrary” within the meaning of Section 223a of the New
York Real Property Law or any successor Requirement.

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(c) Effective as of the Third Additional Premises Commencement Date, Tenant
shall lease the Third Additional Premises upon all of the terms and conditions
of the Original Lease, except as follows:

(i) The fixed rent payable under the Lease with respect to the Third Additional
Premises shall be an amount equal to $173,604.00 per annum ($14,467.00 per
month) for the period commencing on the date which is three (3) months following
the Third Additional Premises Commencement Date and ending on the Third
Additional Premises Expiration Date, both dates inclusive. Tenant shall pay one
installment of fixed rent upon the execution and delivery of this Amendment. If
the Third Additional Premises Commencement Date is on the first day of the
month, such payment shall be credited towards such month’s installment of fixed
rent. If the Third Additional Premises Commencement Date is not the first day of
a month, then on the Third Additional Premises Commencement Date Tenant shall
pay fixed rent for the period from the Third Additional Premises Commencement
Date through the last day of such month, and the payment made by Tenant on the
date of execution and delivery of this Amendment shall be credited towards
monthly fixed rent for the next succeeding calendar month.

(ii) The Third Additional Premises shall be deemed to consist of 2,553 rentable
square feet for all purposes of this Amendment and the Lease.

(iii) Tenant shall pay all additional rent payable pursuant to the Original
Lease including Article Twenty-Four hereof, except with respect to the Third
Additional Premises only, (i) “Base Real Estate Taxes” shall mean the R.E. Tax
Share of the Real Estate Taxes for the Computation Year beginning on January 1,
2001 and ending on December 31, 2001 (i.e., one-half of the R.E. Tax Share of
the Real Estate Taxes for the Tax Year beginning on July 1, 2000 and ending on
June 30, 2001 and one-half of the R.E. Tax Share of the Real Estate Taxes for
the Tax Year beginning on July 1, 2001 and ending on June 30, 2002) and
(ii) “Base COM” shall mean the O.E. Share of the Cost of Operation and
Maintenance for the Computation Year beginning on January 1, 2001 and ending on
December 31, 2001.

(iv) Tenant has inspected the Third Additional Premises and agrees (i) to accept
possession of the Third Additional Premises in their “as is” condition existing
on the Third Additional Premises Commencement Date, (ii) that neither Landlord
nor Landlord’s agents have made any representations or warranties with respect
to the Third Additional Premises or the Building except as expressly set forth
herein, and (iii) Landlord has no obligation to perform any work, supply any
materials, incur any expense or make any alterations or improvements to the
Third Additional Premises to prepare the Third Additional Premises for Tenant’s
occupancy (except as expressly set forth herein). Tenant’s occupancy of any part
of the Third Additional Premises shall be conclusive evidence, as against
Tenant, that (A) Tenant has accepted possession of the Third Additional Premises
in their then current condition, and (B) the Third Additional Premises and the
Building are in a good and satisfactory condition as required by this Amendment.

(v) The provisions of Article Thirty of the Original Lease shall apply to the
Third Additional Premises, except that the reference to “$67,385.00” contained
in Section 30.5 of the Original Lease shall be replaced with “$72,760.50”.

(vi) Tenant shall maintain in good order and repair, the sprinkler system and
fire alarm and life safety system serving the Third Additional Premises. Such
maintenance shall be performed by Tenant in accordance with the Lease, the rules
and regulations and all Requirements. If the Fire Insurance Rating Organization
or any Governmental Authority or any of Landlord’s insurers requires or
recommends any modifications or Alterations be made or any additional equipment
be supplied in connection with the sprinkler system or fire alarm and
life-safety system serving the Building or the Third Additional Premises by
reason of Tenant’s business, or the location of the partitions, trade fixtures,
or other contents of the Third Additional Premises, Landlord (to the extent such
modifications or Alterations are structural, affect any Building System or
involve the performance of work outside the Third Additional Premises), or
Tenant (to the extent such modifications or Alterations are nonstructural, do
not affect any Building System and do not involve the performance of work
outside the Third Additional Premises) shall make such modifications or
Alterations, and supply such additional equipment, in either case at Tenant’s
expense.

 

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(vii) Except as provided in this Amendment, all references in the Original Lease
to the “Premises” shall be deemed to mean the Original Premises and the Third
Additional Premises for all purposes of the Lease. With respect to the Third
Additional Premises only, all references in the Original Lease to “term” or
“term of this Lease” or words of similar import shall be deemed to refer to the
term of the leasing of the Third Additional Premises commencing on the Third
Additional Premises Commencement Date and ending on the Third Additional
Premises Expiration Date.

(viii) Landlord shall provide heating, ventilation and air-conditioning service
to the Premises in accordance with the provisions of Article Twenty of the
Original Lease, except that such heating, ventilation and air-conditioning
service shall be provided in accordance with the standards set forth in Exhibit
B attached hereto during Business Hours on Business Days. Landlord shall not be
responsible if the normal operation of the Building system providing heating,
ventilation and air-conditioning to the Premises (the “HVAC System”) shall fail
to provide cooled or heated air, as the case may be, in accordance with the
specifications set forth in Exhibit B by reason of (x) any machinery or
equipment installed by or on behalf of Tenant, which shall have an electrical
load in excess of the average electrical load and human occupancy factors for
the HVAC System as designed, as the case may be, or (y) any rearrangement of
partitioning or other alterations made or performed by or on behalf of Tenant.
For purposes hereof, “Business Days” shall mean all days, excluding Saturdays,
Sundays and all days observed by either the State of New York, the Federal
Government or the labor unions servicing the Building as legal holidays.

(ix) Landlord shall cause the Premises to be cleaned in accordance with the
provisions of Article Twenty of the Original Lease, except that such cleaning
shall be done in accordance with the standards set forth in Exhibit C attached
hereto. Any areas of the Premises requiring cleaning which Landlord is not
required to clean under Section 20.1 of the Original Lease, and any additional
cleaning of any portion of the Premises requested by Tenant shall be done, at
Tenant’s expense, by Landlord’s employees or Landlord’s contractor, at rates
which shall be competitive with rates of other cleaning contractors providing
services to first-class office buildings in midtown Manhattan. Landlord’s
cleaning personnel shall have access to the Premises at all times except between
8:00 A.M. and 5:30 P.M. on Business Days.

(x) Third Additional Premises End of Term. (a) Expiration. Upon the Third
Additional Premises Expiration Date or the expiration or other termination of
the Lease, Tenant shall quit and surrender the Third Additional Premises to
Landlord, vacant, broom clean and in good order and condition, ordinary wear and
tear and damage for which Tenant is not responsible under the terms of the Lease
excepted, and Tenant shall remove all of Tenant’s personal property and any
alterations made by Tenant or on Tenant’s behalf within the Third Additional
Premises and Center.

(b) Holdover Rent. Landlord and Tenant recognize that the damage to Landlord
resulting from any failure by Tenant to timely surrender possession of the Third
Additional Premises may be substantial, may exceed the amount of the fixed rent
and additional rent theretofore payable hereunder, and will be impossible to
accurately measure. Tenant, therefore, agrees that if possession of the Third
Additional Premises is not surrendered to Landlord on or before the Third
Additional Premises Expiration Date or sooner termination of the Term, in
addition to any other rights or remedies Landlord may have hereunder or at law,
Tenant shall

(i) pay to Landlord for each month (or any portion thereof) during which Tenant
holds over in the Third Additional Premises after the Third Additional Premises
Expiration Date or sooner termination of the Term, a sum equal to the greater of
(1) two times the fixed rent and additional rent applicable to the Third
Additional Premises payable under the Lease for the last full calendar month of
the Term, or (2) one and one-half times the fair market rental value of the
Third Additional Premises for such month (as reasonably determined by Landlord);

(ii) be liable to Landlord for (1) any payment or rent concession which Landlord
may be required to make to any tenant obtained by Landlord for all or any part
of the Third Additional Premises (a “New Tenant”) in order to induce such New
Tenant not to terminate its lease by reason of the holding over by Tenant, and
(2) the loss of the benefit of the bargain if any New Tenant shall terminate its
lease by reason of the holding over by Tenant; and

 

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(iii) indemnify Landlord against all claims for damages by any New Tenant.

No holding over by Tenant, nor the payment to Landlord of the amounts specified
above, shall operate to extend the Term. Nothing herein contained shall be
deemed to permit Tenant to retain possession of the Third Additional Premises
after the Third Additional Premises Expiration Date or sooner termination of the
Lease, and no acceptance by Landlord of payments from Tenant after the Third
Additional Premises Expiration Date or sooner termination of the Term shall be
deemed to be other than on account of the amount to be paid by Tenant in
accordance with the provisions of this clause (x). Nothing contained in this
clause (x) shall be deemed to modify the provisions of Section 25.7 of the
Original Lease with respect to a holdover by Tenant in that portion of the
Premises that excludes the Third Additional Premises.

(c) Waiver of Stay. Tenant expressly waives, for itself and for any person or
entity claiming through or under Tenant, any rights which Tenant or any such
person or entity may have under the provisions of Section 2201 of the New York
Civil Practice Law and Rules and of any successor law of like import then in
force, in connection with any holdover summary proceedings which Landlord may
institute to enforce the foregoing provisions of this clause (x).

3. Modifications. Effective as of the date hereof, the Original Lease shall be
amended as follows:

(a) Section 6.1 (k) of the Original Lease is amended by (i) deleting the
reference to “$1,000,000” contained therein and substituting “$5,000,000”
therefor; (ii) deleting the reference to “$2,000,000” contained therein and
substituting “$5,000,000” therefor; and (iii) deleting the last sentence thereof
and inserting the following provision in its place:

“In addition, Tenant, at Tenant’s expense, shall obtain and keep in full force
and effect during the term of this Lease, (i) insurance against loss or damage
by fire, and such other risks and hazards as are insurable under then available
standard forms of “all risk” property insurance policies with extended coverage,
insuring Tenant’s goods, furniture and furnishings, all Fixtures removable by
Tenant as provided in this Lease, and all of Tenant’s alterations and
improvements to the Premises, for the full insurable value thereof or
replacement cost value thereof, having a deductible amount, if any, as
reasonably determined by Landlord; (ii) during the performance of any
alteration, until completion thereof, Builder’s risk insurance on an “all risk”
basis and on a completed value form including a Permission to Complete and
Occupy endorsement, for full replacement value covering the interest of Landlord
and Tenant (and their respective contractors and subcontractors), any lessor of
an underlying lease and any holder of an underlying mortgage in all work
incorporated in the Building and all materials and equipment in or about the
Premises; (iii) Workers’ Compensation Insurance, as required by law;
(iv) Business Interruption Insurance; and (v) such other insurance in such
amounts as Landlord, any holder of an underlying mortgage and/or any lessor of
an underlying lease may reasonably require from time to time. All insurance
required to be carried by Tenant pursuant to the terms of this Lease shall
contain a provision that (x) the policy shall not be canceled unless Landlord
and each additional insured shall have received 30 days’ prior notice of the
same, by certified mail, return receipt requested, (y) Tenant shall be solely
responsible for the payment of all premiums under such policies and Landlord,
the lessors of underlying leases and holders of underlying mortgages shall have
no obligation for the payment thereof, and (z) shall be effected under valid and
enforceable policies issued by reputable and independent insurers permitted to
do business in the State of New York, and rated in Best’s Insurance Guide, or
any successor thereto (or if there be none, an organization having a national
reputation) as having a Best’s Rating of “A” and a “Financial Size Category” of
at least “IX” or if such ratings are not then in effect, the equivalent thereof
or such other financial rating as Landlord may at any time consider appropriate.
Landlord and Tenant shall each procure an appropriate clause in or endorsement
to any property insurance covering the Premises, the Building and personal
property, fixtures and equipment located therein, wherein the insurance
companies shall waive subrogation or consent to a waiver of right of recovery,
and Landlord and Tenant agree not to make any claim against, or seek to recover
from, the other for any loss or damage to its property or the property of others
resulting from fire and other hazards to the extent covered by such property
insurance; provided, however, that the release, discharge, exoneration and

 

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covenant not to sue contained herein shall be limited by and coextensive with
the terms and provisions of the waiver of subrogation or waiver of right of
recovery. If the payment of an additional premium is required for the inclusion
of, or consent to, a waiver of subrogation, each party shall advise the other,
in writing, of the amount of any such additional premiums and the other party
may pay such additional premium. If such other party shall not elect to pay such
additional premium, then the first party shall not be required to obtain such
waiver of subrogation or consent to waiver. Tenant acknowledges that Landlord
shall not carry insurance on, and shall not be responsible for, (i) damage to
any Alterations or improvements to the Premises, to the extent they exceed
Building standard installations, (ii) any property of Tenant, and (iii) any loss
suffered by Tenant due to interruption of Tenant’s business. Tenant shall
deliver to Landlord appropriate policies of insurance, including evidence of
waivers of subrogation, required to be carried by it pursuant to this Lease.
Evidence of each renewal or replacement of a policy shall be delivered by Tenant
to Landlord at least 10 days prior to the expiration of such policy. In lieu of
the policies of insurance required to be delivered to Landlord pursuant to this
paragraph (the ‘Policies’), Tenant may deliver to Landlord a certification from
Tenant’s insurance company (on the form currently designated “Acord 27”, or the
equivalent, rather than on the form currently designated “Acord 25-S”, or the
equivalent) which shall be binding on Tenant’s insurance company, and which
shall expressly provide that such certification (1) conveys to Landlord and any
other named insured and/or additional insureds thereunder (the ‘Insured
Parties’) all the rights and privileges afforded under the Policies as primary
insurance, and (2) contains an unconditional obligation of the insurance company
to advise all Insured Parties in writing at least 30 days in advance of any
termination of the Policies.”

(b) Article Eight of the Original Lease is amended by adding the following
Section 8.3 at the end thereof:

“8-3. Fire Alarm System; Sprinklers. If due to a change in Requirements the
Premises are required to be sprinklered, Landlord may at any time during the
Term install a sprinkler system and fire alarm and life safety system in the
Premises. Tenant shall pay, within 30 days after demand, as Additional Rent, the
cost of such installation, which cost shall be pro-rated based on the remaining
portion of the Term; provided, however, if such systems are required to be
installed any time during the last 2 years of the Term, Landlord shall pay for
the cost of such installation. Tenant shall afford Landlord and its employees,
contractors and agents access to the Premises at all times for the performance
of such work (and there shall be no Rent abatement or allowance to Tenant for a
diminution of rental value, no actual or constructive eviction of Tenant, in
whole or in part, no relief from any of Tenant’s obligations under this Lease,
and no liability on the part of Landlord, by reason of inconvenience, annoyance
or injury to business arising from the performance of such work). Landlord shall
use reasonable efforts to minimize interference with Tenant’s use and occupancy
of the Premises during the performance of any such repair or restoration;
provided, however, Landlord shall have no obligation to employ contractors or
labor at overtime or other premium pay rates or to incur any other overtime
costs or additional expenses whatsoever. Tenant shall thereafter maintain in
good order and repair, the sprinkler system and fire-alarm and life-safety
system serving the Premises. Such maintenance shall be performed by Tenant in
accordance with this Lease, the Rules and Regulations and all Requirements. If
the Fire Insurance Rating Organization or any Governmental Authority or any of
Landlord’s insurers requires or recommends any modifications or Alterations be
made or any additional equipment be supplied in connection with the sprinkler
system or fire alarm and life-safety system serving the Building or the Premises
by reason of Tenant’s particular manner of use of the Premises (as distinguished
from general office use), or the location of the partitions, trade fixtures, or
other contents of the Premises, Landlord (to the extent such modifications or
Alterations are structural, affect any Building System or involve the
performance of work outside the Premises), or Tenant (to the extent such
modifications or Alterations are non-structural, do not affect any Building
System and do not involve the performance of work outside the Premises) shall
make such modifications or Alterations, and supply such additional equipment, in
either case at Tenant’s expense.”

(c) Section 2(c)(iii) of the Second Amendment to Lease is amended by deleting
the first reference to “Tax Year” contained therein and by substituting the
reference to “Computation Year” therefor.

 

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(d) Article Twenty-Six of the Original Lease, Section 6 of the First Amendment
to Lease, and Section 2(c)(v) of the Second Amendment to Lease are deleted and
replaced by the following:

“ARTICLE TWENTY-SIX

SECURITY

Section 26.1 Security Deposit. (a) Tenant shall deposit $154,252 (the ‘Security
Deposit’) with Landlord upon the execution of the Third Amendment to Lease in
respect of this Lease in cash as security for the faithful performance and
observance by Tenant of the terms, covenants and conditions of this Lease,
including the surrender of possession of the Premises to Landlord as herein
provided.

(b) Landlord shall deposit the Security Deposit in a standard interest-bearing
security deposit account in a bank located in New York State. To the extent not
prohibited by law, Landlord shall be entitled to receive and retain as an
administrative expense an amount equal to interest on the Security Deposit at
the rate of 1% per annum, which fee Landlord shall have the right to withdraw,
at any time and from time to time, as Landlord may determine. The balance of the
interest shall be paid to Tenant annually, within a reasonable time following
the date upon which the depository bank customarily makes interest payments.
Landlord shall not be required to credit Tenant with any interest for any period
during which Landlord does not receive interest on the Security Deposit.

Section 26.2 Letter of Credit. In lieu of a cash deposit, Tenant may deliver the
Security Deposit to Landlord in the form of a clean, irrevocable,
non-documentary and unconditional letter of credit in the amount of the Security
Deposit (the ‘Letter of Credit’) issued by and drawable upon any commercial
bank, trust company, national banking association or savings and loan
association with offices for banking and drawing purposes in the City of New
York (the ‘Issuing Bank’), which has outstanding unsecured, uninsured and
unguaranteed indebtedness, or shall have issued a letter of credit or other
credit facility that constitutes the primary security for any outstanding
indebtedness (which is otherwise uninsured and unguaranteed), that is then
rated, without regard to qualification of such rating by symbols such as “+” or
“-” or numerical notation, “Aa” or better by Moody’s Investors Service and “AA”
or better by Standard & Poor’s Ratings Service (and is not on credit-watch with
negative implications), and has combined capital, surplus and undivided profits
of not less than $500,000,000. The Letter of Credit shall (i) name Landlord as
beneficiary, (ii) be in the amount of the Security Deposit, (iii) have a term of
not less than one year, (iv) permit multiple drawings, (v) be fully transferable
by Landlord without the payment of any fees or charges, and (vi) otherwise be in
form and content satisfactory to Landlord; provided, however, that Landlord
shall in no event be obligated to accept a Letter of Credit for any amount less
than $50,000. If upon any transfer of the Letter of Credit, any fees or charges
shall be so imposed, then such fees or charges shall be payable solely by Tenant
and the Letter of Credit shall so specify. The Letter of Credit shall provide
that it shall be deemed automatically renewed, without amendment, for
consecutive periods of one year each thereafter during the Term through the date
that is at least 60 days after the Expiration Date, unless the Issuing Bank
sends a notice (the ‘Non-Renewal Notice’) to Landlord by certified mail, return
receipt requested, not less than 30 days prior to the then-current expiration
date of the Letter of Credit, stating that the Issuing Bank has elected not to
renew the Letter of Credit. Landlord shall have the right, upon receipt of a
Non-Renewal Notice, to draw the full amount of the Letter of Credit, by sight
draft on the Issuing Bank, and shall thereafter hold or apply the cash proceeds
of the Letter of Credit pursuant to the terms of this Article 26. The Letter of
Credit shall state that drafts drawn under and in compliance with the terms of
the Letter of Credit will be duly honored upon presentation to the Issuing Bank
at an office location in New York City. The Letter of Credit shall be subject in
all respects to the International Standby Practices 1998, International Chamber
of Commerce Publication No. 590.

Section 26.3 Application of Security. If Tenant defaults in the payment or
performance of any the terms, covenants or conditions of this Lease, including
the payment of Rent, Landlord may use, apply or retain the whole or any part of
the cash Security Deposit or may notify the Issuing Bank and thereupon

 

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receive all or a portion of the Security Deposit represented by the Letter of
Credit, and use, apply, or retain the whole or any part of such proceeds, as the
case may be, to the extent required for the payment of any Rent or any other sum
as to which Tenant is in default, including (i) any sum which Landlord may
expend or may be required to expend by reason of Tenant’s default, and (ii) any
damages or Deficiency to which Landlord is entitled pursuant to this Lease or
applicable Requirements, whether such damages or Deficiency accrues before or
after summary proceedings or other reentry by Landlord. If Landlord uses,
applies or retains any part of the Security Deposit, Tenant, upon demand, shall
deposit with Landlord the amount so applied or retained so that Landlord shall
have the full Security Deposit on hand at all times during the Term. If Tenant
shall fully and faithfully comply with all of the terms, covenants and
conditions of this Lease, the Security Deposit (or so much thereof as remains)
shall be returned to Tenant after the Expiration Date and after delivery of
possession of the Premises to Landlord in the manner required by this Lease.
Tenant expressly agrees that Tenant shall have no right to apply any portion of
the Security Deposit against any of Tenant’s obligations to pay Rent hereunder.

Section 26.4 Transfer. Upon a sale of the Building or the Real Property or a
leasing of the Building, or any financing of Landlord’s interest therein,
Landlord shall have the right to transfer the cash Security Deposit or the
Letter of Credit, as applicable, to the vendee, lessee or lender. With respect
to the Letter of Credit, within 10 days after notice from Landlord of any such
anticipated sale, leasing or financing, Tenant, at its sole cost, shall arrange
for the transfer of the Letter of Credit to the new landlord or lender, as
designated by Landlord in the foregoing notice, or to have the Letter of Credit
reissued in the name of the new landlord or lender. Tenant shall look solely to
the new landlord or lender for the return of such cash Security Deposit or
Letter of Credit, and the provisions of this Section 26.4 shall apply to every
transfer or assignment made of the Security Deposit to a new landlord. Tenant
will not assign or encumber, or attempt to assign or encumber, the cash Security
Deposit or Letter of Credit, and neither Landlord nor its successors or assigns
shall be bound by any such actual or attempted assignment or encumbrance.

Section 26.5 Reduction. If Tenant (a) has not previously defaulted in its
obligation to pay fixed rent or additional rent to Landlord within the time
periods set forth in the Lease beyond any applicable notice and cure period, and
(b) is not then in default in the due keeping, observance or performance of any
term or condition of the Lease, then, provided that Tenant complies with the
provisions of this Section 26.5, on or after the 3rd anniversary of the Second
Additional Premises Commencement Date, the Security Deposit shall be reduced to
$130,359.50. The Security Deposit shall be reduced as follows: (A) if the
Security Deposit is in the form of cash, Landlord shall, within 30 Business Days
following notice by Tenant to Landlord that Tenant is entitled to reduce the
Security Deposit pursuant to this Section 26.5, deliver to Tenant the amount by
which the Security Deposit is reduced, or (B) if the Security Deposit is in the
form of a Letter of Credit, Tenant shall deliver to Landlord an amendment to the
Letter of Credit (which amendment must be reasonably acceptable to Landlord in
all respects), reducing the amount of the Letter of Credit by the amount of the
permitted reduction, and Landlord shall execute the amendment and such other
documents as are reasonably necessary to reduce the amount of the Letter of
Credit in accordance with the terms hereof. If Tenant delivers to Landlord an
amendment to the Letter of Credit in accordance with the terms hereof, Landlord
shall, within 30 Business Days after delivery of such amendment, either
(1) provide its reasonable objections to such amendment or (2) execute such
amendment of the Letter of Credit in accordance with the terms hereof.”

4. Brokerage. Each of Landlord and Tenant represents and warrants to the other
that it has not dealt with any broker in connection with this Amendment other
than Tishman Speyer Properties, L.P. (“Broker”) and that, to the best of its
knowledge, no other broker negotiated this Amendment or is entitled to any fee
or commission in connection herewith. Landlord shall pay Broker any commission
which may be due in connection with this Amendment pursuant to a separate
agreement. Each of Landlord and Tenant shall indemnify, defend, protect and hold
the other party harmless from and against any and all losses, liabilities
damages, claims, judgments, fines, suits, demands, costs, interest and expenses
of any kind or nature (including reasonable attorneys’ fees and disbursements)
incurred in connection with any claim, proceeding or judgment and the defense
thereof which the indemnified party may incur by reason of any claim of or
liability to any broker, finder or like agent (other than

 

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Broker) arising out of any dealings claimed to have occurred between the
indemnifying party and the claimant in connection with this Amendment, or the
above representation being false. The provisions of this Paragraph 4 shall
survive the expiration or earlier termination of the term of the Lease.

5. Representations and Warranties. Tenant represents and warrants to Landlord
that, as of the date hereof, (a) the Original Lease is in full force and effect
and has not been modified except pursuant to this Amendment; (b) there are no
defaults existing under the Lease; (c) there exist no valid abatements, causes
of action, counterclaims, disputes, defenses, offsets, credits, deductions, or
claims against the enforcement of any of the terms and conditions of the Lease;
(d) this Amendment has been duly authorized, executed and delivered by Tenant
and constitutes the legal, valid and binding obligation of Tenant; (e) Landlord
has paid all amounts and performed all work required to be paid or performed
under the Lease in connection with Tenant’s initial occupancy of the Premises
under the Lease; and (f) Landlord is not in default of any of its obligations or
covenants under the Lease.

6. Miscellaneous.

(a) Except as set forth herein, nothing contained in this Amendment shall be
deemed to amend or modify in any respect the terms of the Original Lease and
such terms shall remain in full force and effect as modified hereby. If there is
any inconsistency between the terms of this Amendment and the terms of the
Original Lease, the terms of this Amendment shall be controlling and prevail.

(b) This Amendment contains the entire agreement of the parties with respect to
its subject matter and all prior negotiations, discussions, representations,
agreements and understandings heretofore had among the parties with respect
thereto are merged herein.

(c) This Amendment may be executed in duplicate counterparts, each of which
shall be deemed an original and all of which, when taken together, shall
constitute one and the same instrument.

(d) This Amendment shall not be binding upon Landlord or Tenant unless and until
Landlord shall have delivered a fully executed counterpart of this Amendment to
Tenant.

(e) This Amendment shall be binding upon and inure to the benefit of Landlord
and Tenant and their successors and permitted assigns.

(f) This Amendment shall be governed by the laws of the State of New York
without giving effect to conflict of laws principles thereof.

(g) The captions, headings, and titles in this Amendment are solely for
convenience of reference and shall not affect its interpretation.

 

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IN WITNESS WHEREOF, Landlord, and Tenant have executed this Amendment as of the
day and year first above written.

 

LANDLORD:

RCPI TRUST By:  

Tishman Speyer Properties, L.P., its Agent

By:   LOGO [g42721sign.jpg]  

Geoffrey P. Wharton

Senior Managing Director

TENANT:

ANTIGENICS, INC. By:   LOGO [g42721sign1.jpg]  

Garo Armen

Chief Executive Officer

 

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EXHIBIT A

THIRD ADDITIONAL PREMISES FLOOR PLAN

The floor plan that follows is intended solely to identify the general location
of the Third Additional Premises of the Building and should not be used for any
other purpose. All areas, dimensions, and location’s are approximate, and any
physical conditions indicated may not exist as shown.

 

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[Floorplan graphic omitted as not material to investors; a copy will be
furnished upon request.]

 

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EXHIBIT B

HEATING, VENTILATION AND AIR CONDITIONING SPECIFICATIONS

The HVAC System shall be capable of maintaining 78 degrees Fahrenheit when
summer outdoor conditions are 92 degrees Fahrenheit dry bulb and 74 degrees
Fahrenheit wet bulb. The HVAC System shall be capable of maintaining 68 degrees
Fahrenheit at winter outdoor conditions of 11 degrees Fahrenheit. The HVAC
System shall be capable of handling (i) an electrical usage load of not more
than 4 watts per usable square foot; (ii) an occupancy rate of one (1) person
per 150 usable square feet; and (iii) a ventilation make-up rate of 20 cubic
feet per minute per person with the blinds or shades drawn on the exposure
subject to direct solar radiation.

 

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EXHIBIT C

CLEANING SPECIFICATIONS

GENERAL

All hard surface flooring to be dust mopped nightly. All other floor maintenance
shall be done at Tenant’s expense.

All carpeting and rugs to be carpet swept nightly and vacuumed twice monthly.

Hand dust nightly all furniture tops and exposed surfaces of shelves, ledges and
bookcases within reach.

Empty and wipe clean all wastebaskets nightly and remove the contents thereof
from the Premises.

Empty and wipe clean all ash trays and screen all sand urns nightly.

Wash clean all water fountains and coolers nightly.

Dust all door and other ventilating louvers within reach, as necessary.

Dust all telephones as necessary.

Sweep all private stairway structures nightly.

All windows, interiors and exteriors, are to be washed approximately five times
per year.

Do all high dusting approximately once every three months, namely:

Dust all pictures, frames, charts, graphs and similar wall hangings not reached
in nightly cleaning.

Dust clean all vertical surfaces, such as walls, partitions, doors, bucks and
other surfaces not reached in nightly cleaning.

Dust clean all pipes, ventilating and air conditioning louvers, ducts,
diffusers, high moldings and other high areas not reached in nightly cleaning.

Dust all lighting fixtures, including exterior surfaces of diffusers and
enclosures.

Dust all venetian blinds.

CORE LAVATORIES

Sweep and wash all lavatory floors nightly, using disinfectants.

Wash and disinfect all basins, bowls and urinals nightly.

Wash and disinfect all toilet seats nightly.

Hand dust and clean, washing where necessary, all partitions, tile walls,
dispensers and receptacles in all lavatories and restrooms nightly.

 

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Empty paper towel receptacles and transport wastepaper from the Premises
nightly.

Fill toilet tissue holders nightly (tissue to be furnished by Landlord).

Empty sanitary disposal receptacles nightly.

Wash interior of wastecans and receptacles at least once a week.

If core lavatory is within Tenant’s space, the soap and towel dispenser will be
filled at Tenant’s direction at Tenant’s expense. If core lavatory is on a
public corridor, the soap and towel dispenser will be maintained by Landlord.

PUBLIC AND CORE AREAS AND ELEVATORS

Dust mop all floors nightly and wash once a week. Spray buff resilient tile
flooring on a semi-monthly schedule.

Inspect, maintain and keep clean firehoses, extinguishers and similar equipment
as necessary.

Spot wash walls of corridors and public stairways as necessary.

Empty and screen all cigarette urns daily.

Mop floor in public stairwells once per week.

Dust elevator doors and frames, and Building directories as required.

********

“Nightly”, as used herein, shall be exclusive of Saturdays, Sundays and
holidays.

 

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