EXHIBIT 10.26 STANDARD COMMERCIAL-INDUSTRIAL LEASE

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                                                                   EXHIBIT 10.26

                      STANDARD COMMERCIAL-INDUSTRIAL LEASE

1. PARTIES. This Lease dated, for reference purposes only DECEMBER 30, 1997 is
made by and between TUCSON TECH PARK (herein called "Lessor") and IMARX
PHARMACEUTICAL CORPORATION (herein called "Lessee").

2. PREMISES. Lessor hereby leases to Lessee and Lessee leases from Lessor for
the term, at the rental and upon all the conditions set forth herein that
certain real property situated in the County of Pima State of Arizona commonly
known as: Suite 100, located at 1700 East 18th Street, Tucson, Arizona 85719.
Approximately 1500 sq ft as shown on the attached site plan, and described on
Exhibit A attached premises outlined in red hereto and made a part hereof. Said
real property including the land and all improvements thereon is herein called
"the Premises". All dimensions and areas quoted herein are approximate.

3. TERM.

     3.1 TERM. The term of this Lease shall be for one year less 15 days
commencing on February 15, 1998 and ending on January 31, 1999 unless sooner
terminated pursuant to any provision hereof.

     3.2 DELAY IN COMMENCEMENT. Notwithstanding said commencement date, if for
any reason Lessor cannot deliver possession of the Premises to Lessee on said
date, Lessor shall not be subject to any liability therefore, nor shall failure
affect the validity of this Lease or the obligations of Lessee hereunder or
extend the term hereof, but in such case Lessee shall not be obligated to pay
rent until possession of the Premises is tendered to Lessee; provided, however
that if Lessor shall not have delivered possession of the Premises within sixty
(60) days from said commencement date, Lessee may, at Lessee's option, by notice
in writing to Lessor within ten (10) days thereafter cancel this Lease, in which
event the parties shall be discharged from all obligations hereunder. If Lessee
occupies the Premises prior to said commencement date such occupancy shall be
subject to all provisions hereof; such occupancy shall not advance the
termination date, and Lessee shall pay rent for such period at the initial
monthly rates set forth below. If Lessor by reason outside the reasonable
control of Lessor, cannot deliver said premises within ninety (90) days from
said commencement date, Lessor may at Lessor's option, by notice in writing
within ten (10) days thereafter cancel this Lease.

4. RENT. Lessee shall pay by the first day of each month, Lessor a monthly
rental of eight hundred forty and no/00 dollars ($840.00) in lawful money of the
United States of America for each and every month of the Lease. The Lessee
further agrees to pay in addition to the rent as provided herein all privilege,
sales, excise, and other taxes (except income taxes) imposed by State Federal,
or municipal upon the rentals herein provided to be paid by the Lessee to the
Lessor. Said payment shall be in addition to and accompanying each rental
payment made by Lessee to Lessor.

Rent for any period during the term hereof which is for less than one month
shall be a pro rata portion of the monthly installment. Rent shall be payable in
lawful money of the United States to Lessor at the address stated herein or to
such other persons or at such other places as Lessor may designate in writing.
The rent due under terms of this Paragraph may be modified by Paragraph Eleven
(11) below.

5. SECURITY DEPOSIT. Lessee shall deposit with Lessor upon execution hereof
$840.00 as security for Lessee's faithful performance of Lessee's obligations
hereunder. If Lessee fails to pay rent or other charges due hereunder or
otherwise defaults with respect to any provision of this Lease. Lessor may use
apply, or retain all or any portion of said deposit for the payment of any rent
or other charge in default or for the payment of any other sum to which Lessor
may become obligated by reason of Lessee's default, or to compensate Lessor for
any loss or damage which Lessor may suffer thereby if Lessor so uses or applies
all of any portion of said deposit Lessee shall within ten (10) days after
written demand thereof deposit cash with Lessor in an amount sufficient to
restore said deposit to the full amount hereinabove stated, and Lessee's failure
to do so shall be a material breach of this Lease. Lessor shall not be required
to keep said deposit separate from its general accounts. If Lessee performs all
of Lessee's obligations hereunder, said deposit, or so much thereof as has not
theretofore been applied by Lessor, shall be returned, without payment of
interest or other increment for its use to Lessee (or at Lessor's option, to the
last assignee, if any, of Lessee's interest hereunder) at the expiration of the
term hereof, and after Lessee has vacated the premises.

6. USE.

     6.1 USE. The Premises shall be used and occupied only for research and
associated activities, including but not limited to storage, records
maintenance, general office, etc. and for no other purpose Lessee shall not use,
or permit to be used, the Premises or any part thereof, for any purpose or
purposes other than the purpose or purposes for which said Premises are hereby
leased; and no use shall be made or permitted to be made of said Premises, which
will increase the existing rate of insurance upon the building in which said
Premises may be located, or cause a cancellation of any insurance policy
covering said building, or any part thereof, nor shall Lessee sell, or permit to
be kept, used, or sold, in or about said Premises, any article which may be
prohibited by standard form of fire Insurance policies.

     6.2 COMPLIANCE WITH LAW. Lessee shall at Lessee's expense, comply promptly
with all applicable statutes, ordinances, rules, regulations, orders, and
requirements in effect during the term or any part of the term hereof regulating
the use by Lessee of the Premises Lessee shall not use or permit the use of the
Premises in any manner that will tend to create waste or a nuisance or, if there
shall be more than one tenant of the building containing the Premises, which
shall tend to disturb such other tenants.

     6.3 CONDITION OF PREMISES. Lessee hereby accepts the Premises in their
condition existing as of the date of the execution hereof, subject to all
applicable zoning, municipal, county and state laws, ordinances and regulations
governing and regulating the use of the Premises, and accepts this Lease subject
thereto and to all matters disclosed thereby and by any exhibits attached
hereto. Except as otherwise stated in this Lease, Lessee hereby acknowledges
that neither the Lessor nor any employees or agents of Lessor has made any oral
or written warranties or representations to Lessee relative to the condition or
use by Lessee of said Premises and Lessee acknowledges that Lessee assumes all
responsibility regarding the Occupational Safety Health Act, the legal use and
adaptability of the Premises and the compliance thereof with all applicable laws
and regulations in effect during the term of this Lease except as otherwise
specifically stated in this Lease.

7. MAINTENANCE, REPAIRS AND ALTERATIONS.

     7.1 LESSOR'S OBLIGATIONS. Subject to the provisions of Paragraph 9 and
except for damage caused by any negligent or intentional act or ommission of
Lessee. Lessee's agents employees, or invitees Lessor, at Lessor's expense shall
keep in good order, condition, and repair the foundations, exterior walls, and
the exterior roof of the Premises. The Lessee shall give the Lessor prompt
notice of any defects or breakage in the structure, equipment fixtures, or of
any unsafe conditions upon or within the Leased Premises. Lessee expressly
waives the benefits of any statute now or hereafter in effect which would
otherwise afford Lessee the right to make repairs at Lessor's expense or to
terminate this Lease because of Lessor's failure to keep the Premises in good
order, condition, and repair.

     7.2 LESSEE'S OBLIGATIONS.

     (a) Subject to the provision of Paragraphs 7 and 9, Lessee, at Lessee's
expense shall keep in good order and in a neat and sanitary condition and repair
the Premises and every part thereof (whether or not the damaged portion of the
Premises or the means of repairing the same are reasonably or readily accessible
to Lessee) including, without limiting the generality of the foregoing, all
plumbing, heating air conditioning, ventilating, electrical and lighting
facilities and equipment within the Premises, fixtures, interior walls and
interior surface of exterior walls, ceilings, windows, doors plate glass, and
skylights, located within the Premises, and all landscaping, driveways, parking
lots fences and signs located in the Premises and all areas immediately adjacent
to the Premises. Notwithstanding the foregoing the Lessor shall maintain and
repair all Lessee's expense the heating and cooling equipment and shall bill
Lessee for said work.

     (b) If Lessee fails to perform Lessee's obligations under this Paragraph
7.2, Lessor may at Lessor's option enter upon the Premises after ten (10) day's
prior written notice to Lessee and put the same in good order condition and
repair, and the cost thereof together with interest thereon shall be due and
payable as additional rent to Lessor together with Lessee's next rental
installment.

7.3 ALTERATIONS AND ADDITIONS.

     (a) Lessee shall not without Lessor's prior written consent make any
alterations, improvements or additions in, on or about the Premises. Lessor may
require that Lessee, at Lessee's expense, remove any or all of said alterations,
improvements, or additions at the expiration of the term, and restore the
Premises to their prior condition. Should Lessee make any alterations,
improvements or additions without the prior approval of Lessor. Lessor may
require that Lessee remove the same. Anything herein contained to the contrary
notwithstanding, Lessee shall not drill, punch or otherwise cause any crack,
hole, opening or other break in the roof or roof area, or roof supports, or in
the floors, on the walls or in other permanent areas or structures without first
receiving the prior written consent of Lessor.

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          (b) Any alterations improvements or additions in, or about the
Premises that Lessee shall desire to make and which requires the consent of the
Lessor shall be presented to Lessor in written form with proposed detailed
plans. If Lessor shall give its consent the consent shall be deemed conditioned
upon Lessee acquiring a permit to do so from appropriate governmental agencies
the furnishing of a copy thereof to Lessor prior to the commencement of the work
and the compliance by Lessee of all conditions of said permit in a prompt and
expeditious manner. In addition, Lessor may require Lessee to provide Lessor, at
Lessee's sole cost and expense, a lien and completion bond in an amount equal to
one and one half times the estimated costs of such improvements to insure Lessor
against any liability for mechanics and materialmen's liens and to insure
completion of the work.

          (c) Lessee shall pay when due all claims for labor or materials
furnished or alleged to have been furnished to or for Lessee at or for use in
the Premises, which claims are or may be secured by any mechanics or
materialmen's lien against the Premises or any interest therein. Lessee shall
give Lessor not less than ten (10) days notice prior to the commencement of any
work in the Premises and Lessor shall have the right to post notices of
non-responsibility in or on the Premises as provided by law. If Lessee shall in
good faith, contest the validity of any such lien, claim or demand then Lessee
shall at its sole expenses defend itself and Lessor against the same and shall
pay and satisfy any such adverse judgment that may be rendered thereon before
the enforcement thereof against the Lessor or the Premises, upon the condition
that if Lessor shall require, Lessee shall furnish to Lessor a surely bond
satisfactory to Lessor in an amount equal to such contested lien claim or demand
indemnifying Lessor against liability for the same and holding the Premises free
from the effect of such lien or claim in addition. Lessor may require Lessee to
pay Lessor's attorney's fees and costs in participating in such action if Lessor
shall decide it is to its best interest to do so.

          (d) Unless Lessor requires their removal as set forth in Paragraph
7.3(a) all alterations improvements and additions which may be made on the
Premises shall become the property of Lessor and remain upon and be surrendered
with the Premises at the expiration of the term or on sooner termination
thereof.

8. INSURANCE; INDEMNITY.

     8.1. Liability Insurance. Lessee shall at Lessees expense obtain and keep
in force during the term of this Lease a policy of comprehensive public
liability Insurance insuring Lessor and Lessee against any liability arising out
of the ownership use occupancy or maintenance of the Premises and all areas
appurtenant thereto. Such insurance shall be in an amount of not less than
$300,000 for injury to or death of one person in any one accident or occurrence
and any amount of not less than $500,000 for injury to or death of more than one
person in any one accident or occurrence. Such Insurance shall further insure
Lessor and Lessee against liability for property damage of at least $50,000. The
limits of said insurance shall not, however limit the liability of Lessee
hereunder. In the event that the Premises constitute a part of a larger property
said insurance shall have a Lessor's Protective Liability endorsement attached
thereto. If Lessee shall fail to procure and maintain said Insurance Lessor may,
but shall not be required to, procure and maintain the same, but at the expense
of Lessee.

     8.2 PROPERTY INSURANCE.

          (a) Lessor shall obtain and keep in force during the term of this
Lease a policy or policies of insurance covering loss or damage to the Premises
and loss of rents; but not Lessee's fixtures equipment or tenant improvements in
such amount as Lessor shall determine providing protection against all perils
included within the classification of fire extended coverage, vandalism,
malicious mischief, special extended perils (all risk) but not plate glass
insurance.

          (b) Lessee shall pay to Lessor, during the term hereof. In addition to
the rent the amount of any increase in premiums for the insurance required under
this Paragraph 8.2 over and above such premiums paid during the Base Period as
hereinafter defined, whether such premium increase shall be the result of the
nature of Lessee's occupancy, any act or omission of Lessee, requirements of the
holder of a mortgage or deed of trust covering the Premises or increased
valuation of the Premises or general rate increases. In the event that the
Premises have been occupied previously the words "Base Period" shall mean the
last twelve months of the prior occupancy and in the event that the Premises
have never been previously occupied the words "Base Period" shall mean the
lowest premium reasonably obtainable for the said insurance for the Premises
assuming the most nominal use of the Premises.

          (c) If the Premises being leased herein are part of a larger property,
then Lessee shall not be responsible for paying any increase in the property
insurance caused by the acts or omissions of any other tenant of the building in
which the Premises are a part.

          (d) Lessee shall pay any such premium increases to Lessor within
thirty (30) days after receipt by Lessee of a copy of the premium statement or
other satisfactory evidence of the amount due. If the insurance policies
maintained hereunder cover other improvements in addition to the Premises,
Lessor shall also deliver to Lessee a statement of the amount of such increase
attributable to the Premises and showing in reasonable detail the manner in
which such amount was computed. If the term of this Lease does not expire
concurrently with the expiration of the period covered by such insurance
Lessee's liability for premium increases shall be prorated on an annual basis.

     8.3 INSURANCE POLICIES. Lessee shall deliver to Lessor copies of policies
of liability insurance required under Paragraph 8.1 or certificates evidencing
the existence and amounts of such insurance with loss payable clauses
satisfactory to Lessor. No such policy shall be cancellable or subject to
reduction of coverage or other modification except after ten (10) days prior
written notice to Lessor. Lessee shall within ten (10) days prior to the
expiration of such policies furnish Lessor with renewals or binders thereof, or
Lessor may order such insurance and charge the cost thereof to Lessee which
amount shall be payable by Lessee upon demand Lessee shall not do or permit to
be done anything which shall invalidate the insurance policies referred to in
Paragraph 8.2.

     8.4 WAIVER OF SUBROGATION. Lessee and Lessor each hereby waives any and all
rights of recovery against the other or against the officers employees, agents
and representatives of the other, for business interruption or for loss of or
damage to such waiving party or its property or the property of others under its
control, where such business interrupting loss or damage is insured against
under any insurance policy in force at the time of such business interrupting
loss or damage: Lessee and Lessor shall, upon obtaining the policies of
insurance required hereunder give notice to the insurance carrier or carriers
that the foregoing mutual waiver of subrogation is contained in this Lease.

     8.5 INDEMNIFY. Lessee shall indemnify and hold harmless Lessor from and
against any and all claims arising from Lessee's use of the Premises or from the
conduct of Lessee's business or from any activity, work or things, done
permitted or suffered by Lessee in or about the Premises or elsewhere and shall
further indemnify and hold harmless Lessor from and against any and all claims
arising from any breach or default in the performance of any obligation on
Lessee's part to be performed under the terms of this Lease or arising from any
negligence of the Lessee, or any of Lessee's agents contractors or employees,
and from and against all costs attorney's fees expenses and liabilities incurred
in the defense of any such claim or any action or proceeding brought thereon and
in case any action or proceeding be brought against Lessor by reason of any such
claim. Lessee upon notice from Lessor shall defend the same at Lessee's expense
by counsel satisfactory to Lessor.

     8.6 EXEMPTION OF LESSOR FROM LIABILITY. Lessee hereby agrees that Lessor
shall not be liable for injury to Lessee's business or any loss of income
therefrom or for damage to the goods wares, merchandise or other property of
Lessee. Lessee's employees, invitees customers or any other person in or about
the Premises nor shall Lessor be liable for injury to the person of Lessee.
Lessee's employees, agents or contractors, whether such damage or injury is
caused by or results from fire, steam electricity, gas, water or rain or from
the breakage, leakage, obstruction or other defects of pipes, sprinklers, wires,
appliances, plumbing, air conditioning or lighting fixtures or from any other
cause, whether the said damage or injury results from conditions arising upon
the Premises or upon other portions of the building of which the Premises are a
part, or from other sources or places and regardless of whether the cause of
such damage or injury or the means of repairing the same is inaccessible to
Lessee.

9. DAMAGE OR DESTRUCTION.

     9.1 PARTIAL DAMAGE-INSURED. Subject to the provisions of Paragraphs 9.3 and
9.4 if the Premises are damaged and such damage was caused by a casualty covered
under an insurance policy required to be maintained and pursuant to Paragraph
8.2, Lessor shall at Lessor's expense repair such damage as soon as reasonably
possible and this Lease shall continue in full force and effect but Lessor shall
not repair or replace Lessee's fixtures, equipment or tenant improvements.

     9.2 PARTIAL DAMAGE-UNINSURED. Subject to the provisions of Paragraphs 9.3
and 9.4 if at any time during the term hereof the Premises are damaged, except
by a negligent or willful act of Lessee (in which event Lessee shall make the
repairs at its expense) and such damage was caused by a casualty not covered
under an insurance policy required to be maintained pursuant to Paragraph 8.2.
Lessor may at Lessor's option either (i) repair such damage as soon as
reasonably possible at Lessor's expense, in which event this Lease shall
continue in full force and effect, or (ii) give written notice to Lessee within
thirty (30) days after the date of the occurrence of such damage of Lessor's
intention to cancel and terminate this Lease as of the date of the occurrence of
such damage in the event Lessor elects to give such notice of Lessor's intention
to cancel and terminate this Lease. Lessee shall have the right within ten (10)
days after the receipt of such notice to give written notice to Lessor of
Lessee's intention to repair such damage at Lessee's expense, without
reimbursement from Lessor, in which event this Lease shall continue in full
force and effect and Lessee shall proceed to make such repairs as soon as
reasonably possible. If Lessee does not give such notice within such 10-day
period this Lease shall be cancelled and terminated as of the date of the
occurrence of such damage.

     9.3 TOTAL DESTRUCTION. If at any time during the term hereof the Premises
are totally destroyed from any cause whether or not covered by the insurance
required to be maintained by Lessor pursuant to Paragraph 8.2 (including any
total destruction required by any authorized public authority) this Lease shall
automatically terminate as of the date of such total destruction.

     9.4 DAMAGE NEAR END OF TERM. If the Premises are partially destroyed or
damaged during the last six (6) months of the term of this Lease Lessor may at
Lessors option cancel and terminate this Lease as of the date of occurren