FOURTH AND BATTERY OFFICE LEASE

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                                                                    EXHIBIT 10.8

                               FOURTH AND BATTERY
                                  OFFICE LEASE

          THIS LEASE, made the 28th day of April, 2003 (the "Execution Date"),
by and between SELIG REAL ESTATE HOLDINGS EIGHT, a Washington limited liability
company, whose address is 1000 Second Avenue, Suite 1800, Seattle, Washington,
98104-1046, hereinafter referred to as "Lessor" and GENECRAFT, INC., a Delaware
corporation, whose address is 601 Union Street, Suite 4200, Seattle, Washington
98101, hereinafter referred to as "Lessee".

          1. DESCRIPTION. Lessor in consideration of the agreements contained in
this lease, does hereby lease to Lessee, upon the terms and conditions
hereinafter set forth, that certain space consisting of the agreed upon square
footage* of 24,090 (hereinafter referred to as "Premises"), 8,198 square feet of
which is situated on the Tenth (10th) floor level and 15,892 square feet of
which is situated on the Twelfth (12th) floor level of the Fourth & Battery
Building, 2401 Fourth Avenue, City of Seattle, State of Washington 98121 (the
"Building"), the legal description of which is:

          Lots 3, 4, 5, 6, 7 and 8, Block 35, Bell and Denny's Second Addition
          to City of Seattle.

          Suites 1050 and 1200

*     Rentable square footage stated above is an estimate of the rentable square
     footage and is deemed to be the correct square footage of the Premises and
     is based on the Building Owners and Managers Association Standard Method
     for Measuring Area in Office Buildings (ANSI/BOMA Z65.1-1996).

          2. TERM. Lessor represents that it has entered into and given Lessee a
true, correct and complete copy of a lease termination agreement with LifeSpan
BioSciences, Inc., a Washington corporation ("LifeSpan"), the current tenant in
the Premises, which provides that LifeSpan's lease of the Premises (the "Current
Lease") shall terminate and LifeSpan shall vacate the Premises as follows: (i)
LifeSpan will vacate and the Current Lease shall terminate as to the portion of
the tenth (10th) floor included in the Premises on May 15, 2003, (ii) LifeSpan
will vacate and the Current Lease shall terminate as to the south half of the
twelfth (12th) floor of the Premises by June 1, 2003 and (iii) LifeSpan will
vacate and the Current Lease shall terminate as to the north half of the twelfth
(12th) floor of the Premises by August 15, 2003 (each of May 15, 2003, June 1,
2003 and August 15, 2003 being a "Delivery Date" as to the applicable portion of
the Premises). Lessor shall deliver possession of the applicable portion of the
Premises to Lessee on each Delivery Date in good, vacant, broom clean condition,
with all building systems in good working order and in compliance with all laws,
with all systems and equipment operated therein properly decontaminated and
decommissioned and with the roof water tight and otherwise in the condition as
of the date of this Lease. Tenant's acceptance of the

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Premises shall not be deemed a waiver of Tenant's right to have defects in the
Premises repaired at no cost to Tenant. Tenant shall give notice to Landlord
whenever any such defect becomes reasonably apparent, and Landlord shall repair
such defect as soon as practicable. Landlord shall use commercially reasonable
efforts to enforce the provisions of such lease termination agreement against
LifeSpan and to deliver the Premises to Lessee on the dates and in the condition
set forth above, including, without limitation, commencing appropriate unlawful
detainer and/or eviction proceedings against LifeSpan.

          The term of this lease shall be for a period of eighty-four (84)
months, commencing on October 1, 2003 (the "Commencement Date"); provided,
however, that the Commencement Date shall be delayed by one (1) calendar day for
each calendar day that (i) delivery of the applicable portion of the Premises in
the required condition is delayed beyond the applicable Delivery Date as set
forth above and (ii) substantial completion of the Tenant Improvements is
delayed due to Lessor's delay, force majeure, the presence of Hazardous
Materials in the Building or any work required to bring the Building into
compliance with laws except for compliance with laws exclusive to Lessee's
Tenant Improvements other than general laboratory improvements. Notwithstanding
anything to the contrary herein, if the Commencement Date is delayed for any of
the foregoing reasons for more than thirty (30) calendar days, then in addition
to Lessee's other rights or remedies, Lessee may terminate this Lease by written
notice to Lessor, whereupon any monies previously paid by Lessee to Lessor shall
be reimbursed to Lessee, or, at Lessee's election, the date Lessee is otherwise
obliged to commence payment of rent shall be delayed by one additional calendar
day for each calendar day that the Commencement Date is delayed beyond such
date.

          Upon each Delivery Date, Lessee shall have the right to occupy the
applicable portion of the Premises for purposes of the construction of the
initial Tenant Improvements or otherwise. Such occupancy shall be subject to all
of the terms of this Lease except the obligation to pay Rent and shall not
advance the Commencement Date.

          In the event the Premises are not ready for occupancy on the date set
forth above, whether occasioned by Lessor or Lessee, the lease term shall be
extended in such a manner as to reflect the delay occasioned by the failure of
the Premises to be ready for occupancy. In no event shall Lessor or Lessee be
liable for any further damages.

          3. RENT. Lessee covenants and agrees to pay Lessor rent each month in
advance on the first day of each calendar month during the Lease Term in the
amount of $63,270 per month. Rent for any fractional calendar month, at the
beginning or end of the term, shall be the pro rated portion of the rent
computed on an annual basis. Lessor and Lessee agree that Lessee has designated
portions of the Premises identified on Exhibit A attached hereto consisting in
the aggregate of 3,000 rentable square feet as "space pockets" (the "Space
Pockets"). The Space Pockets may be occupied by Lessee without the payment of
Rent for the purpose of constructing the Tenant Improvements and thereafter for
the purpose of storing furniture, equipment and other personal property;
however, in the event that Lessee's employees occupy all or any portion of the
Space Pockets for the purpose of conducting Lessee's business therein, then
Lessee shall


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commence payment of Rent for the portions of such Space Pockets so occupied at
the rate of thirty-six dollars ($36.00) per square foot per year.
Notwithstanding the foregoing, (i) on the first day of the thirteenth (13th)
month of the Lease term, Lessee shall commence the payment of Rent at the rate
of thirty-six dollars ($36.00) per square foot per year as to fifteen hundred
rentable square feet of the Space Pockets, less any portion of the Space Pockets
that Lessee has previously occupied and commenced the payment of Rent as of such
date and (ii) on the first day of the twenty-fifth (25th) month of the Lease
term, Lessee shall commence the payment of Rent at the rate of thirty-six
dollars ($36.00) per square foot per year as to the remaining fifty percent
(50%) of the rentable square footage of the Space Pockets, and thereafter there
shall be no further Space Pockets in the Premises.

          4. CONSIDERATION. Lessee has this date paid to Lessor the sum of
$126,540 (as prepayment for the first and second month's rent), receipt of which
is hereby acknowledged. So long as Lessee is not in default of its obligations
under the terms and conditions of this lease as of the first day of each of the
first and second months of the Lease Term, an amount equal to $63,270 (fifty
percent of such sum) shall be credited to the first and second month's rental
due under this lease.

          5. USES. Lessee agrees that Lessee will use and occupy said Premises
for general offices, laboratory, research and development uses and a rodent
research laboratory and related purposes only and for no other purposes, without
Lessor's prior written consent (the "Permitted Use").

          6. RULES AND REGULATIONS. Lessee and their agents, employees, servants
or those claiming under Lessee will at all times observe, perform and abide by
all of the Rules and Regulations printed on this instrument, or which may be
hereafter promulgated by Lessor, all of which it is covenanted and agreed by the
parties hereto shall be and are hereby made a part of this lease.
Notwithstanding anything to the contrary herein, Lessee shall not be required to
comply with any new rule or regulation unless the same applies
non-discriminatorily to all occupants of the Building, does not unreasonably
interfere with Lessee's use of the Premises or Lessee's parking rights and does
not materially increase the obligations or decrease the rights of Lessee under
this Lease.

          7. CARE AND SURRENDER OF PREMISES. Lessee shall take good care of the
Premises and shall promptly make all necessary repairs except those required
herein to be made by Lessor. At the expiration or sooner termination of this
lease, Lessee, without notice, will immediately and peacefully quit and
surrender the Premises in good order, condition and repair (damage by reasonable
wear, the elements, fire, casualties, condemnation, Hazardous Materials (other
than those released or emitted by Lessee), and alterations or other interior
improvements which it is permitted to surrender at the termination of the Lease,
excepted). Lessee shall be responsible for removal of all personal property from
the Premises, (excepting fixtures being that which is attached to the Premises,
and property of the Lessor) including, but not limited to, the removal of
Lessee's communication cabling, telephone equipment and signage. Lessee shall be
responsible for repairing any damage to the Premises caused by such removal. If
Lessee fails to remove and restore the Premises at lease expiration, then Lessor
shall have the right to remove


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said property and restore the Premises and Lessee shall be responsible for all
costs associated therewith. Lessee shall also be responsible for those costs
incurred by Lessor for removing debris Lessee may discard in the process of
preparing to vacate the Premises and for a final cleaning of the Premises,
including, but not limited to, the cleaning, or replacement of carpets if damage
is not caused by reasonable wear, and removal and disposal of Lessee's personal
property remaining in the Premises.

          8. ALTERATIONS. Lessee shall not make any alterations or improvements
in, or additions to said Premises ("Alterations") without first obtaining the
written consent of Lessor, whose consent shall not be unreasonably withheld;
provided however, that if Lessor has not granted or denied its consent to any
such proposed Alterations within five (5) business days after its receipt of
Lessee's written request for such approval, then Lessor shall be deemed to have
approved such Alterations. All such alterations, additions and improvements
shall be at the sole cost and expense of Lessee and shall become the property of
Lessor and shall remain in and be surrendered with the Premises as a part
thereof at the termination of this lease, without disturbance, molestation or
injury. Notwithstanding anything to the contrary herein, (a) Alterations and
Lessee's trade fixtures, furniture, equipment and other personal property
installed in the Premises (except for any of the foregoing paid for with the
proceeds of the Allowance) ("Lessee's Property") shall at all times be and
remain Lessee's property, (b) except for Alterations which cannot be removed
without structural injury to the Premises, at any time Lessee may remove
Lessee's Property from the Premises, provided that Lessee repairs all damage
caused by such removal, (c) Lessor shall have no lien or other interest in any
item of Lessee's Property and (d) Lessor shall have no right to require Lessee
to remove any alterations unless it notifies Lessee at the time it consents (or
is deemed to have consented) to such alteration that it shall require such
alteration to be removed.

          9. RESTRICTIONS. Lessee will not use or permit to be used in said
Premises anything that will increase the rate of insurance on said building or
any part thereof (except for the Permitted Use), nor anything that may be
dangerous to life or limb; nor in any manner deface or injure said building or
any part thereof; nor overload any floor or part thereof; nor permit any
objectionable noise or odor to escape or to be emitted from said Premises, or do
anything or permit anything to be done upon said Premises in any way tending to
create a nuisance or to disturb any other tenant or occupant of any part of said
building. Lessee, at Lessee's expense, will comply with all health, fire and
police regulations respecting said Premises. The Premises shall not be used for
lodging or sleeping, and no animals or birds will be allowed in the building
(except as permitted under the Permitted Use). Notwithstanding anything to the
contrary herein, Lessee shall not be required to comply with or cause the
Premises to comply with any laws, rules or regulations requiring the
construction of alterations unless such compliance is necessitated solely due to
Lessee's particular use of the Premises.

          10. WEIGHT RESTRICTIONS. Safes, furniture or bulky articles may be
moved in or out of said Premises only at such hours and in such manner as will
least inconvenience other tenants, which hours and manner shall be at the
discretion of Lessor. No safe or other article of over 2,000 pounds shall be
moved into said Premises without the


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consent of Lessor, whose consent shall not be unreasonably withheld, and Lessor
shall have the right to locate the position of any article of weight in said
Premises if Lessor so desires.

          11. SIGN RESTRICTION. No sign, picture, advertisement or notice shall
be displayed, inscribed, painted or affixed to any of the glass or woodwork of
the building without the prior approval of Lessor. Notwithstanding the
foregoing, Lessor shall install, at Lessor's cost and expense, appropriate
building standard signage identifying Lessee's name at all entry level building
directories, and on the suite door(s) or entryway(s).

          12. LOCKS. No additional locks shall be placed upon any doors of the
Premises. Keys will be furnished to each door lock. At the termination of the
lease, Lessee shall surrender all keys to the Premises whether paid for or not.

          13. KEY. Lessor, his janitor, engineer or other agents may retain a
pass key to said Premises to enable him to examine the Premises from time to
time with reference to any emergency or to the general maintenance of said
Premises. Notwithstanding anything to the contrary herein, Lessor and Lessor's
agents, except in the case of emergency, shall provide Lessee with one (1)
business day notice prior to entry of the Premises. Any entry by Lessor and
Lessor's agents shall not impair Lessee's operations more than reasonably
necessary, and shall comply with Lessee's reasonable security measures, all
applicable laws and regulations and all of Lessee's policies and procedures,
including, without limitation, all posted notices and instructions.

          14. TELEPHONE SERVICE. If Lessee desires telephonic or any other
electric connection, Lessor will direct the electricians as to where and how the
wires are to be introduced, and without such directions no boring or cutting for
wires in installation thereof will be permitted.

          15. SERVICES. Lessor shall maintain Premises and the public and common
areas of building, such as lobbies, stairs, corridor and restrooms, in
reasonably good order and condition except for damage occasioned by the act of
Lessee. Notwithstanding anything to the contrary herein, Lessor shall perform
and construct, and Lessee shall have no responsibility to perform or construct,
any repair, maintenance or improvements (a) necessitated by the acts or
omissions of Lessor or any other occupant of the Building, or their respective
agents, employees or contractors, (b) for which Lessor has a right of
reimbursement from others, (c) to the structural portions of the Premises, (d)
which could be treated as a "capital expenditure" under generally accepted
accounting principles, (e) to the heating, ventilating, air conditioning,
electrical, water, sewer, and plumbing systems serving the Premises and the
Building; provided, however, that Lessee shall obtain a one (1) year warranty on
any Tenant Improvements made to such systems, and (f) to any portion of the
Building outside of the demising walls of the Premises. Notwithstanding the
foregoing, Lessee shall pay for its share of the repairs described in
subsections (d)-(f) to the extent such costs are properly included in Operating
Services.


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          Lessor shall furnish Premises with electricity for lighting and
operation of low power usage office machines, laboratory machines up to a
maximum amount of 4.5 watts per square foot per year, heat, normal office and
laboratory air-conditioning, and elevator services, during the ordinary business
hours of the building. Air-conditioning units and electricity therefor for
special air-conditioning requirements, such as for computer centers, shall be at
Lessee's expense. Lessor shall also provide lighting replacement for Lessor
furnished lighting, toilet room supplies, window washing with reasonable
frequency, and customary janitor service. Lessor shall provide all services,
which are normally provided in similar office buildings in the general area in a
first class and a cost efficient manner. Lighting and HVAC shall be provided
without additional charge between the hours of 7 a.m. to 7 p.m., Monday through
Friday and between 7 a.m. to 1 p.m., Saturdays throughout the year except
Christmas Day, Thanksgiving, New Year's Day, Memorial Day, Independence Day and
Labor Day. Any after hour services, which Lessee requires, will be provided upon
request at Lessee's cost. There shall be no Lessor profit or mark up on such
after-hours services, although Lessor may have a right to pass through actual
electricity costs due to Lessee's excessive use of the electricity, water or
HVAC.

          Lessor shall not be liable to Lessee for any loss or damage caused by
or resulting from any variation, interruption or any failure of said services
due to any cause whatsoever. No temporary interruption or failure of such
services incident to the making of repairs, alterations, or improvements, or due
to accident or strike or conditions or events not under Lessor's control shall
be deemed as an eviction of Lessee or relieve Lessee from any of Lessee's
obligations hereunder. Notwithstanding anything to the contrary herein, if the
Premises should become not reasonably suitable for Lessee's use as a consequence
of cessation of utilities or other services, interference with access to the
Premises, legal restrictions or the presence of any Hazardous Material which
does not result from Lessee's release or emission of such Hazardous Material,
and in any of the foregoing cases the interference with Lessee's use of the
Premises persists for fifteen (15) calendar days, then Lessee shall be entitled
to an equitable abatement of rent to the extent of the interference with
Lessee's use of the Premises occasioned thereby. If the interference persists
for more than ninety (90) calendar days, Lessee shall have the right to
terminate this Lease; provided that Lessee has given Lessor at least thirty (30)
calendar days prior written notice of such termination, which notice may be
delivered within such ninety (90) day period.

           In the event of any lack of attention on the part of Lessor and any
dissatisfaction with the service of the building, or any unreasonable annoyance
of any kind, Lessee is requested to make complaints at Lessor's building office
and not to Lessor's employees or agents seen within the building. Lessee is
further requested to remember that Lessor is as anxious as Lessee that a high
grade service be maintained, and that the Premises be kept in a state to enable
Lessee to transact business with the greatest possible ease and comfort. The
rules and regulations are not made to unnecessarily restrict Lessee, but to
enable Lessor to operate the building to the best advantage of both parties
hereto. To this end Lessor shall have the right to waive from time to time such
part or parts of these rules and regulations as in his judgment may not be
necessary for the proper maintenance or operation of the building or consistent
with good service, and may from time to time make such further reasonable rules
and regulations as in his judgment


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may be needed for the safety, care and cleanliness of the Premises and the
building and for the preservation of order therein.

          16. SOLICITORS. Lessor will make an effort to keep solicitors out of
the building, and Lessee will not oppose Lessor in his attempt to accomplish
this end.

          17. FLOOR PLAN. The floor plan and specifications for Lessee's
occupancy shall be attached hereto and marked Exhibit "A" which shall be
approved by both Lessor and Lessee, both of whose approval shall not be
unreasonably withheld.

          18. ASSIGNMENT. Lessee will not assign this lease, or any interest
hereunder without Lessor's prior written consent, which shall not be
unreasonably withheld or delayed, and this lease, or any interest hereunder,
shall not be assigned by operation of law without Lessor's prior written
consent, which shall not be unreasonably withheld or delayed. Lessee will not
sublet said Premises or any part thereof and will not permit the use of said
Premises by others other than Lessee and the agents of Lessee without first
obtaining the written consent of Lessor, whose consent shall not be unreasonably
withheld. In the event such written consent shall be given, no other or
subsequent assignment or subletting shall be made without the previous written
consent of Lessor, whose consent shall not be unreasonably withheld.
Notwithstanding anything to the contrary herein, Lessee may, without Lessor's
prior written consent and without constituting an assignment or sublease
hereunder, sublet the Premises or assign this Lease to (a) an entity
controlling, controlled by or under common control with Lessee, (b) a successor
entity related to Lessee by merger, consolidation, nonbankruptcy reorganization,
or government action, or (c) a purchaser of substantially all of Lessee's assets
located in the Premises. A sale or transfer of Lessee's capital stock shall not
be deemed an assignment, subletting or any other transfer of this Lease or the
Premises.

          19. OPERATING SERVICES AND REAL ESTATE TAXES. The annual base rental
rate per rentable square foot in Paragraph 3 includes Lessee's proportionate
share of Operating Services and Real Estate Taxes for the first twelve months of
the lease term, "Base Year Costs". Only actual increases from these Base Year
Costs, if any, will be passed on to Lessee on a proportionate basis.

                                   DEFINITIONS

Base Year

For computing the Base Year Costs, the base year shall be the calendar year
stated herein or if a specific calendar year is not stated herein then the base
year shall be the calendar year in which the lease term commences. The base year
shall be the calendar year 2004.

Comparison Year

The Comparison Year(s) shall be the calendar year(s) subsequent to the base
year.


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Operating Services

"Operating Services" include, but are not limited to, the charges incurred by
Lessor for building operation salaries, benefits, management fee (not to exceed
5% of gross income for the building), insurance, electricity, janitorial,
supplies, telephone, HVAC, repair and maintenance, window washing, water and
sewer, security, landscaping, disposal, elevator, and any other service or
supplies reasonably necessary to the use and operation of the premises.
Operating Services shall also include the amortization cost of capital
investment items and of the installation thereof, which are primarily for the
purpose of safety, saving energy or reducing operating costs, or which may be
required by governmental authority, (all such costs shall be amortized over the
reasonable life of the capital investment item, with the reasonable life and
amortization schedule being determined in accordance with generally accepted
accounting principles). Notwithstanding anything to the contrary contained
herein, Operating Services shall not include and Lessee shall in no event have
any obligation to perform or to pay directly, or to reimburse Lessor for, all or
any portion of the following repairs, maintenance, improvements, replacements,
premiums, claims, losses, fees, charges, costs and expenses (collectively,
"costs"):

          (i) real estate taxes

          (ii) legal fees, auditing fees, brokerage commissions, advertising
costs, or other related expenses incurred by Lessor in an effort to generate
rental income;

          (iii) repairs, alterations, additions, improvements, or replacements
made to rectify or correct any defect in the original design, materials or
workmanship of the building or common areas (but not including repairs,
alterations, additions, improvements or replacements made as a result of
ordinary wear and tear);

          (iv) damage and repairs and other costs attributable to fire or other
casualty or condemnation;

          (v) damage and repairs necessitated by the negligence or willful
misconduct of Lessor, Lessor's employees, contractors or agents;

          (vi) executive salaries and the salaries of other employees of Lessor
to the extent that such services are not in connection with the management,
operation, repair or maintenance of the Building;

          (vii) Lessor's general overhead expenses not related to the building;

          (viii) legal fees, accountant's fees and other expenses incurred in
connection with disputes with tenants or other occupants of the building or
associated with the enforcement of the terms of any leases with tenants or the
defense of Lessor's title to or interest in the building or any part thereof,
unless the outcome is to the financial benefit of all tenants;


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          (ix) costs (including permit, license and inspection fees) incurred in
renovating or otherwise improving, decorating, painting or altering (1) vacant
space (excluding common areas) in the building or (2) space for tenants or other
occupants in the building and costs incurred in supplying any item or service to
less than all of the tenants in the building;

          (x) costs incurred due to a violation by Lessor or any other tenant of
the building of the terms and conditions of a lease or other agreement;

          (xi) cost of any specific service provided to Lessee or other
occupants of the building for which Lessor is reimbursed (but not including
Operating Services and Real Estate Tax increases above Base Year Costs to the
extent reimbursed Lessor) or any other expense for which Lessor is or will be
reimbursed by another source (i.e., expenses covered by insurance or
warranties);

          (xii) costs and expenses which could be capitalized under generally
accepted accounting principles, wi