================================================================================


                       LIMITED LIABILITY COMPANY AGREEMENT




                                       OF




                             ARCUS THERAPEUTICS LLC




                                     BETWEEN




                             TECHNICLONE CORPORATION




                                       AND




                                  OXiGENE, INC.








                               Dated May 11, 2000


================================================================================

<PAGE>


                                TABLE OF CONTENTS

                                                                            PAGE
                                                                            ----



                                    ARTICLE 1

                           DEFINITIONS; INTERPRETATION

1.1      DEFINITIONS...........................................................2
1.2      INTERPRETATION.......................................................10


                                    ARTICLE 2

                               GENERAL PROVISIONS

2.1      NAME.................................................................10
2.2      PRINCIPAL PLACE OF BUSINESS; REGISTERED OFFICE AND AGENT.............10
2.3      CERTIFICATE OF FORMATION.............................................10
2.4      TERM.................................................................10
2.5      TITLE TO COMPANY PROPERTY............................................11
2.6      CONFIDENTIALITY......................................................11
2.7      PRESS RELEASES.......................................................12


                                    ARTICLE 3

                                     CAPITAL

3.1      CAPITAL CONTRIBUTIONS................................................13
3.2      PAYMENTS TO Techniclone..............................................15
3.3      NO WITHDRAWAL OF CAPITAL; NO INTEREST ON CAPITAL.....................15


                                    ARTICLE 4

                         ALLOCATIONS AND TAX PROVISIONS

4.1      MAINTENANCE OF CAPITAL ACCOUNTS......................................15
4.2      ALLOCATIONS OF PROFITS...............................................16
4.3      ALLOCATION OF LOSSES AND DEDUCTIONS..................................17
4.4      SPECIAL ALLOCATIONS..................................................17
4.5      OTHER ALLOCATIONS RULES..............................................19
4.6      TAX MATTERS MEMBER...................................................19


                                      -i-
<PAGE>


                                    ARTICLE 5

                                  DISTRIBUTIONS

5.1      DISTRIBUTIONS; GENERAL...............................................20
5.2      ADDITIONAL LIMITATIONS ON DISTRIBUTIONS..............................20
5.3      DISTRIBUTIONS TO MEMBERS.............................................20


                                    ARTICLE 6

                            MANAGEMENT AND OPERATION

6.1      MANAGEMENT OF THE COMPANY............................................21
6.2      MANAGEMENT...........................................................22
6.3      PERFORMANCE OF DUTIES................................................22
6.4      DEVOTION OF TIME.....................................................23
6.5      MEETINGS OF THE BOARD................................................23
6.6      QUORUM AND VOTING AT MEETINGS OF MANAGERS............................24
6.7      OFFICERS; COMMITTEES.................................................25
6.8      INTERNAL CONTROLS....................................................25
6.9      FINANCIAL AND BUSINESS INFORMATION AND TAX RETURNS...................25
6.10     BANK ACCOUNTS........................................................26
6.11     INDEPENDENT ENTERPRISE...............................................26
6.12     COMPENSATION.........................................................26
6.13     FIDUCIARY DUTY.......................................................26
6.14     OTHER ACTIVITIES.....................................................26
6.15     NONCOMPETITION.......................................................26
6.16     CONFLICTS OF INTEREST................................................27
6.17     PATENTS..............................................................27
6.18     TRADEMARKS...........................................................27


                                    ARTICLE 7

                  RIGHTS, OBLIGATIONS AND POWERS OF THE MEMBERS

7.1      COMPENSATION OF MEMBERS..............................................28
7.2      SERVICES.............................................................28
7.3      ADMISSION OF ADDITIONAL MEMBERS......................................29


                                    ARTICLE 8

                   LIMITATION UPON LIABILITY; INDEMNIFICATION

8.1      LIMITATION UPON LIABILITY............................................29
8.2      COMPANY'S DEBTS......................................................30
8.3      MEMBER'S DEBTS.......................................................30
8.4      FAILURE TO OBSERVE FORMALITIES.......................................30
8.5      INDEMNIFICATION......................................................30

                                      -ii-
<PAGE>


                                    ARTICLE 9

                REPRESENTATIONS, WARRANTIES AND CERTAIN COVENANTS

9.1      REPRESENTATIONS AND WARRANTIES.......................................31
9.2      ADDITIONAL REPRESENTATIONS AND WARRANTIES OF Techniclone.............32
9.3      ADDITIONAL REPRESENTATIONS AND WARRANTIES OF OXiGENE.................33
9.4      WARRANTY OF STATEMENTS...............................................33
9.5      COVENANTS............................................................33
9.6      SURVIVAL OF REPRESENTATIONS, WARRANTIES AND CERTAIN COVENANTS........34


                                   ARTICLE 10

                         CONDITIONS PRECEDENT TO CLOSING

10.1     CONDITIONS PRECEDENT TO THE OBLIGATIONS OF THE MEMBERS...............34
10.2     DELIVERY TO OXiGENE..................................................35
10.3     DELIVERY TO Techniclone..............................................36
10.4     CLOSING..............................................................36


                                   ARTICLE 11

                                 INDEMNIFICATION

11.1     INDEMNIFICATION......................................................36
11.2     MECHANISM FOR INDEMNIFICATION........................................36


                                   ARTICLE 12

                               DISPUTE RESOLUTION

12.1     DISPUTE..............................................................37
12.2     MEDIATION............................................................37
12.3     ARBITRATION..........................................................37


                                   ARTICLE 13

                        TRANSFERS OF MEMBERSHIP INTERESTS

13.1     OVERALL RESTRICTIONS.................................................39
13.2     ADDITIONAL RESTRICTIONS..............................................39
13.3     PURCHASE PRICE AND PAYMENT DATE......................................39
13.4     CHANGE OF CONTROL....................................................40
13.5     ADMISSION OF SUBSTITUTED MEMBERS.....................................40
13.6     SPECIFIC PERFORMANCE.................................................41

                                      -iii-
<PAGE>


                                   ARTICLE 14

                        SALE, DISSOLUTION AND LIQUIDATION

14.1     EVENTS OF DISSOLUTION................................................41
14.2     FINAL ACCOUNTING AND TAX RETURNS.....................................41
14.3     LIQUIDATION..........................................................42
14.4     DISTRIBUTIONS IN LIQUIDATION.........................................42
14.5     DEFICIT CAPITAL ACCOUNTS.............................................43
14.6     TERMINATION OF COMPANY AND AGREEMENT.................................44


                                   ARTICLE 15

                             ACCOUNTING AND REPORTS

15.1     BOOKS AND RECORDS....................................................44
15.2     ACCOUNTING METHOD....................................................45
15.3     FISCAL YEAR..........................................................45
15.4     REPORTS; TAX RETURNS.................................................45
15.5     REQUIRED GOVERNMENTAL FILINGS........................................46


                                   ARTICLE 16

                               GENERAL PROVISIONS

16.1     NOTICES..............................................................46
16.2     WAIVER...............................................................47
16.3     SEVERABILITY.........................................................47
16.4     WAIVER OF PARTITION..................................................47
16.5     FURTHER ASSURANCES...................................................47
16.6     GOVERNING LAW........................................................47
16.7     COUNTERPARTS.........................................................48
16.8     LIMITATION ON RIGHTS OF OTHERS.......................................48
16.9     SUCCESSORS AND ASSIGNS...............................................48
16.10    ENTIRE AGREEMENT; AMENDMENT..........................................48
16.11    EXPENSES.............................................................48
16.12    CONSTRUCTION.........................................................48
16.13    DISCLAIMER OF AGENCY.................................................48
16.14    RIGHTS AND REMEDIES..................................................49
16.15    ATTORNEYS' FEES......................................................49

                                      -iv-
<PAGE>


                                    EXHIBITS


Exhibit A      University of Texas patent license agreements

Exhibit B      OXiGENE License Agreement

Exhibit C      Core Joint Development Plan

Exhibit D      Sponsored Research Agreement

Exhibit E      VTA Assignment Agreement

Exhibit F      Techniclone Pending Matters

Exhibit G      Agreement among Techniclone, University of Texas and Dr. Philip
               Thorpe

Exhibit H      Form of Joint Press Release

                                      -v-
<PAGE>


                       LIMITED LIABILITY COMPANY AGREEMENT
                                       OF
                             ARCUS THERAPEUTICS LLC

         THIS LIMITED LIABILITY COMPANY AGREEMENT (this "Agreement") of ARCUS
THERAPEUTICS LLC (the "Company") is made as of this 11th day of May, 2000 by and
between TECHNICLONE CORPORATION, a Delaware corporation ("Techniclone"), and
OXiGENE, INC., a Delaware corporation ("OXiGENE").

                                    RECITALS

         A. Techniclone has conducted research and has developed and possesses
certain existing proprietary patent rights, technical information, technology
and know-how relating to vascular targeting agent ("VTA") technology.

         B. OXiGENE and Techniclone believe that the aforementioned VTA patent
rights, technical information, technology and know-how will have important
application to the development of products.

         C. OXiGENE and Techniclone have formed the Company jointly for the
principal purpose of developing VTA technology and, eventually, creating
products based on it.

         D. OXiGENE and Techniclone believe that a joint business effort between
them dedicated to such purposes would be of mutual benefit to the accomplishment
thereof and that the compatibility between Techniclone and OXiGENE is such that
substantial economic returns may be gained by each through cooperative effort.

         E. Techniclone will assign to the Company the Techniclone Contributed
Technology pursuant to the Techniclone Assignment Agreement, for use consistent
with the Plan in consideration for a Membership Interest in the Company, as more
fully set forth herein.

         F. OXiGENE will (i) contribute cash, in the amount and on the terms of
Section 3.1.2 below, and certain resources, in accordance with the Plan, and
(ii) license the OXiGENE Contributed Technology to the Company pursuant to the
OXiGENE License Agreement, for use consistent with the Plan, all in
consideration for a Membership Interest in the Company, as more fully set forth
herein.

         G. The purpose of the Company is to engage in the business of
developing, licensing, promoting and otherwise commercially exploiting the VTA
Technology with a view toward creating, manufacturing, producing, licensing,
selling, marketing and using the VTA Products for commercial purposes both
within the scope of the Plan and through licensing, strategic alliances and
other third party collaborations agreed to by the Members in accordance with
Sections 6.2 through 6.6 of this Agreement outside of the scope of the Plan.

<PAGE>

         H. The parties believe that it is in their best interest to set forth
their mutual understanding with respect to, among other things, management and
operation of the Company and the ownership and Transfer of the Membership
Interests.

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

                                   ARTICLE 1

                           DEFINITIONS; INTERPRETATION
1.1 DEFINITIONS

         Capitalized terms used herein shall have the following meanings:

         "ACCOUNTING SERVICES PROVIDER" has the meaning ascribed to that term in
Section 15.1.

         "ACT" means the Delaware Limited Liability Company Act, as provided in
Title 6, Chapter 18 of the Delaware Code, ss. 101 et seq., as amended from time
to time.

         "ADDITIONAL LICENSING/MILESTONE FEE" means the fee of $2,000,000 in
cash due from OXiGENE to Techniclone in accordance with Section 3.2(b).

         "ADJUSTED CAPITAL ACCOUNT DEFICIT" means, with respect to any Member,
the deficit balance, if any, in such Member's Capital Account as of the end of
the relevant Fiscal Year, after giving effect to the following adjustments:

                  (a) Credit to such Capital Account any amounts that such
Member is obligated to restore pursuant to any provision of this Agreement or is
deemed to be obligated to restore pursuant to the penultimate sentences of
Regulations Sections 1.704-2(g)(1) and 1.704-2(i)(5); and

                  (b) Debit to such Capital Account the items described in
Regulations Sections 1.704-l(b)(2)(ii)(d)(4), 1.704-l(b)(2)(ii)(d)(5) and
1.704-l(b)(2)(ii)(d)(6).

         The foregoing definition of Adjusted Capital Account Deficit is
intended to comply with the provisions of Regulations Section
1.704-l(b)(2)(ii)(d) and shall be interpreted consistently therewith.

         "AFFILIATE" means, with respect to any Person, another Person that,
directly or indirectly, controls, is controlled by or is under common control
with such Person. The term "control" means the possession, directly or
indirectly, of the power to direct or cause the direction of the management and
policies of a Person, whether through the ownership of voting securities, by
contract or otherwise. The direct or indirect ownership of 50% or, if smaller,
the maximum allowed by applicable law, of the voting securities of a business
entity or of an interest in the assets, profits or earnings of an Entity shall
be deemed to constitute "control" of the Entity.

                                      -2-
<PAGE>

         "AGREEMENT" means this Limited Liability Company Agreement, including
all exhibits attached hereto, as originally executed and as amended from time to
time.

         "APPROVED BUDGET" has the meaning ascribed to such term in Section
3.1.4

          "BOARD" means the board of Managers established in accordance with
Section 6.1.

         "CAPITAL ACCOUNT" means the capital account to be determined and
maintained for each Member pursuant to Section 4.1 throughout the existence of
the Company, which shall be interpreted and applied in a manner consistent with
Regulations Section 1.704-1(b).

         "CAPITAL CONTRIBUTION" means, with respect to any Member, the amount of
money and the initial Gross Asset Value of any property (other than money)
contributed to the Company with respect to the Interest held by such Member
reduced by the amount of any liabilities of such Member assumed by the Company
in connection with such Capital Contribution or that is secured by any property
contributed by such Member as a part of such Capital Contribution.

         "CHAIR" means the chairperson of the Board as appointed in Section 6.2.

         "CLOSING DATE" means the date of execution of this Agreement or such
other date as shall be mutually agreed upon by OXiGENE and Techniclone.

         "CODE" means the Internal Revenue Code of 1986, as amended.

         "COMPANY" means the limited liability company formed pursuant to the
Certificate of Formation and this Agreement.

         "COMPANY DISCOVERIES" means all inventions, patents, discoveries and
intellectual property of any type discovered or developed by the Company.
Company Discoveries shall not include any inventions, patents, discoveries and
intellectual property of any type discovered or developed by one of the Members
after the liquidation of the Company. Use of Company Discoveries in the
development of any inventions, patents, discoveries and intellectual property of
any type after the liquidation of the Company by a former Member (the
"developing Member") must be licensed from the other Member if the developing
Member does not have ownership, development and sublicense rights in the Company
Discoveries pursuant to Section 14.4(c).

         "COMPANY MINIMUM GAIN" has the meaning of "partnership minimum gain"
set forth in Regulations Sections 1.704-2(b)(2) and 1.704-2(d).

         "CONFIDENTIAL INFORMATION" has the meaning ascribed to such term in
Section 2.6(a).

         "DEPRECIATION" means, for each Fiscal Year, an amount equal to the
depreciation, amortization or other cost recovery deduction allowable with
respect to an asset for such Fiscal Year, except that if the Gross Asset Value
of an asset differs from its adjusted basis for federal income tax purposes as
of the beginning of such Fiscal Year, Depreciation shall be an amount that bears
the same ratio to such beginning Gross Asset Value as the federal income tax
depreciation, amortization or other cost recovery deduction for such Fiscal Year
bears to such beginning adjusted tax basis; provided, however, that if the
adjusted basis for federal income tax purposes of an asset at the beginning of
such Fiscal Year is zero, Depreciation shall be determined with reference to
such beginning Gross Asset Value using any reasonable method selected by the
Board.

                                      -3-
<PAGE>

         "DISCLOSER" means the Member, and each of its Affiliates, whose
Confidential Information is disclosed or made available to the other Member, and
each of its Affiliates (the "Recipient").

         "EARLY TERMINATION EVENT" means the determination of the Board to
abandon the Plan, including without limitation, the licensing or sale of
substantially all of the Technology to third parties, without incurring the risk
and expense of development by the Company.

         "EARLY TERMINATION PREFERENCE" means

                  (A) in the event of a decision by the Board to cause an Early
Termination Event, the preference equal to 75 percent of all Net Cash From
Operations (with the remaining 25% of such net revenues (the "Early Termination
Remainder"), for as long as the Early Termination Preference is applicable, to
be distributed to OXiGENE in accordance with Section 5.3(d)) derived from any
licensing or sale arrangements made in connection with an Early Termination
Event, until Techniclone has received total Net Cash From Operations and
distributions pursuant to this Early Termination Preference equal to the result
obtained by multiplying (i) two by (ii) the difference between (x) $20,000,000
and (y) OXiGENE's cumulative Capital Contributions made pursuant to Section
3.1.2, which preference will be due and payable to Techniclone in accordance
with Section 5.3(d); and

                  (B) in the event of an Early Termination Event authorized by a
tie-breaking vote of the Board pursuant to Section 6.2.3, all Net Cash From
Operations derived from the Technology and Company Discoveries shall be
distributed to Techniclone in proportion to the Applicable Percentage and to
OXiGENE in proportion to the difference between 100% and the Applicable
Percentage for as long as any Net Cash From Operations are derived from the
Technology or the Company Discoveries. The Applicable Percentage shall mean 100%
MINUS (50% TIMES the percentage derived by dividing OXiGENE's cumulative Capital
Contributions under Section 3.1.2 BY $20,000,000).

          "EARLY TERMINATION REMAINDER" has the meaning ascribed to such term
under the definition of Early Termination Preference.

         "EMPLOYEES OF THE COMPANY" means those persons whose names appear as of
any given time or date on a list to be maintained by the Company, with special
designation thereon with respect to persons engaged in full or part time
operations pursuant to the Plan; provided that the term "Employees of the
Company" may include persons employed solely by the Company as well as persons
who are or have been employed by OXiGENE or Techniclone.

         "ENTITY" means any general partnership, limited partnership, limited
liability partnership, limited liability company, corporation, joint venture,
trust, estate, business trust, cooperative or association or any other
organization that is not a natural Person.

                                      -4-
<PAGE>

         "FIELD" means the field described by the University of Texas patent
license agreements and other license agreements identified in Exhibit A and
defined in the University of Texas agreements as "Licensed Field". The
definition of Field excludes those rights licensed to or in the process of being
licensed to Supergen Pharmaceuticals for the use of Vascular Endothelial Growth
Factor (VEGF) as a targeting agent under the VTA license agreements and those
rights licensed to Scotia Holdings for the use of Photodynamic Therapy (PDT)
applications under the VTA license agreements.

         "FISCAL YEAR" means the accounting year of the Company determined under
Section 15.3.

         "GAAP" has the meaning ascribed to such term in Section 6.8.

         "GROSS ASSET VALUE" means, with respect to any asset, the asset's
adjusted basis for federal income tax purposes, except as follows:

                  (a) The initial Gross Asset Value of any asset contributed by
a Member to the Company shall be the gross fair market value of such asset, as
determined by the contributing Member and the Board, provided that the initial
Gross Asset Value of the assets contributed to the Company pursuant to Section
3.1 shall be as set forth in such Section;

                  (b) The Gross Asset Values of Company assets shall be adjusted
to equal their respective gross fair market values, as determined by the Board,
as of the following times: (i) the acquisition of an additional Interest by any
new or existing Member in exchange for more than a DE MINIMIS Capital
Contribution; (ii) the distribution by the Company to a Member of more than a DE
MINIMIS amount of Property as consideration for an Interest; and (iii) the
liquidation of the Company within the meaning of Regulations Section
1.704-l(b)(2)(ii)(g) provided, however, that the adjustments pursuant to clauses
(i) and (ii) above shall be made only if the Board reasonably determines that
such adjustments are necessary or appropriate to reflect the relative economic
interests of the Members in the Company;

                  (c) The Gross Asset Value of any Company asset distributed to
any Member shall be adjusted to equal the gross fair market value of such asset
on the date of distribution as determined by the distributee and the Board; and

                  (d) The Gross Asset Values of Company assets shall be
increased (or decreased) to reflect any adjustments to the adjusted basis of
such assets pursuant to Code Section 734(b) or Code Section 743(b), but only to
the extent that such adjustments are taken into account in determining Capital
Accounts pursuant to Regulations Section 1.704-l(b)(2)(iv)(m) and Section 4.1
hereof; provided, however, that the Gross Asset Values shall not be adjusted
pursuant to this clause (d) to the extent the Board determines that an
adjustment pursuant to clause (b) is necessary or appropriate in connection with
a transaction that would otherwise result in an adjustment pursuant to this
clause (d).

                  (e) If the Gross Asset Value of an asset has been determined
or adjusted pursuant to clause (a), (b) or (d) above, such Gross Asset Value
shall thereafter be used for purposes of calculating Depreciation with respect
to such asset for purposes of determining Profits and Losses.

                                      -5-
<PAGE>

         "INITIAL LICENSING FEE" means the fee of $3,000,000 in cash due from
OXiGENE to Techniclone in accordance with Section 3.2(a).

         "IND" means the Investigational New Drug Application required by the
U.S. Food and Drug Administration ("FDA") in order to begin clinical trials in
the United States.

         "IRS" means the Internal Revenue Service of the U.S. Department of the
Treasury.

         "MANAGER" means a person appointed to the Board pursuant to Article 6.

         "MEMBER" means each of the parties to this Agreement or its respective
successors and permitted assigns (and, collectively, the "MEMBERS").

         "MEMBER NONRECOURSE DEBT" has the meaning of "partner nonrecourse debt"
set forth in Regulations Section 1.704-2(b)(4).

         "MEMBER NONRECOURSE DEBT MINIMUM GAIN" means an amount, with respect to
each Member Nonrecourse Debt, equal to the Company Minimum Gain that would
result if such Member Nonrecourse Debt were treated as a Nonrecourse Liability
determined in accordance with Regulations Section 1.704-2(i)(3).

         "MEMBERSHIP INTEREST" or "INTEREST" means the interest in the Company
representing each Member's percentage ownership in, and share of Profits and
Losses of, and the right to receive distributions under Sections 5.1 and 14.4
from, the Company. The Membership Interest of each Member is fifty percent
(50%), unless adjusted pursuant to Section 3.1.

         "NET CASH FROM OPERATIONS" means (a) prior to the contribution in full
of OXiGENE's Capital Contribution under Section 3.1.2, all revenues from the
operation of the Company's business from whatever source derived (other than
cash referred to in Sections 5.3(a) and (b) below), as reduced by cash expenses
incurred for such operation, and (b) after the contribution in full of OXiGENE's
Capital Contribution under Section 3.1.2, all revenues from the operation of the
Company's business from whatever source derived (other than cash referred to in
Sections 5.3(a) and (b) below), as reduced by expenses incurred or accrued for
such operation, including reasonable reserves for amounts that the Board
determines necessary to sustain operations of the Company's business in
accordance with the Plan.

         "NONRECOURSE DEDUCTIONS" has the meaning set forth in Regulations
Section 1.704-2(b)(1).

         "NONRECOURSE LIABILITY" has the meaning set forth in Regulations
Section 1.704-2(b)(3).

         "OPERATING COMMITTEE" has the meaning ascribed to such term in Section
3.1.4.

         "OXIGENE CONTRIBUTED TECHNOLOGY" means all of the proprietary rights,
technical information, technology and know-how, including inventions, patents,
copyrights, trade secrets, methods, processes, technologies, software, clinical
data, technical data and the like, certification marks, confidential business
information, and all licenses and sublicenses, applications, registrations and
renewals regarding any of the foregoing, including any continuing developments
or improvements of such information, technology and know-how, owned or

                                      -6-
<PAGE>

controlled (with the power to license the requisite interest therein without the
necessity of obtaining the prior consent thereto of any other person) by OXiGENE
as of the Closing Date or developed by, for or on behalf of OXiGENE thereafter,
that are included within the next generation of OXiGENE's tubulin binding
agents, other than compounds derived from the bush willow Combretum caffrum and
analogs thereof, that are used or useful, in combination with either (i) the
Techniclone Contributed Technology or (ii) the development of VTA Technology
that includes or is based on Techniclone Contributed Technology and possibly the
creation of VTA Products solely pursuant to the Plan; OXiGENE Contributed
Technology will be licensed to the Company as of the Closing Date pursuant to
the OXiGENE License Agreement, as identified on Exhibit B.

          "OXIGENE LICENSE AGREEMENT" means the OXiGENE License Agreement to be
entered into between the Company and OXiGENE as of the Closing Date in
connection with the OXiGENE Contributed Technology that is attached hereto as
Exhibit B.

         "PENDING MATTERS" means the licensing arrangements in place or in
negotiation as more specifically set forth on Exhibit F between Techniclone and
Alza Corp., Antisoma PLC, Bristol Meyers Squibb Corp., BZL Corporation, Cytogen
Corp., Genentech Inc., Hoffman La Roche, Inc., ILEX Oncology, Inc., Scotia,
Smith Kline Beecham/Glaxo and Supergen, Inc. relating to VTA Technology.

          "PERSON" means any individual or Entity, and the heirs, executors,
administrators, legal representatives, successors and assigns of such Person
where the context so permits.

         "PLAN" means the Core Joint Development Plan entered into between
OXIGENE and Techniclone in the form of Exhibit C. Both parties acknowledge that
this Plan is subject to change or amendment by the Members as the Members
perceive the need to expand, contract, modify or amend the methods, costs or
means for developing and exploiting the Technology.

         "PROFITS" and "LOSSES" mean the net taxable income and net tax loss of
the Company computed for each Fiscal Year or other relevant period, as
determined in accordance with Code Section 703(a) (for this purpose, all items
of income, gain, loss, or deduction required to be stated separately pursuant to
Code Section 703(a)(1) shall be included in taxable income or loss), with the
following adjustments:

                  (a) Any income of the Company that is exempt from federal
income tax and not otherwise taken into account in computing Profits and Losses
pursuant to this clause (a) shall be added to such taxable income or loss;

                  (b) Any expenditures of the Company described in Code Section
705(a)(2)(B) (including expenditures treated as described in Code Section
705(a)(2)(B) under Regulations Section 1.704-l(b)(2)(iv)(i)), and not otherwise
taken into account in computing Profits and Losses pursuant to this definition,
shall be subtracted from such taxable income or loss;

                  (c) In the event the Gross Asset Value of any Company asset is
adjusted pursuant to the terms of this Agreement, the amount of such adjustment
shall be taken into account as gain or loss from the disposition of such asset
for purposes of computing Profits and Losses;

                                      -7-
<PAGE>

                  (d) Gain or loss resulting from any disposition of Property
with respect to which gain or loss is recognized for federal income tax purposes
shall be computed by reference to the Gross Asset Value of the Property disposed
of, notwithstanding that the adjusted tax basis of such Property differs from
its Gross Asset Value;

                  (e) In lieu of the depreciation, amortization and other cost
recovery deductions taken into account in computing such taxable income or loss,
there shall be taken into account Depreciation for such Fiscal Year, computed in
accordance with the terms hereof;

                  (f) To the extent an adjustment to the adjusted tax basis of
any Company asset pursuant to Code Section 734(b) or Code Section 743(b) is
required pursuant to Regulations Section 1.704-l(b)(2)(iv)(m)(4) to be taken
into account in determining Capital Accounts as a result of a distribution other
than in liquidation of the Member's interest, the amount of such adjustment
shall be treated as an item of gain (if the adjustment increases the basis of
the asset) or loss (if the adjustment decreases the basis of the asset) from the
disposition of the asset and shall be taken into account for purposes of
computing Profits or Losses; and

                  (g) Notwithstanding any other provisions of this Agreement,
any items that are specially allocated by the Company pursuant to Sections
4.2(a) and (b), 4.4 or 4.5 shall not be taken into account in computing Profits
or Losses. The amount of the items of Company income, gain, loss or deduction
available to be specially allocated pursuant to Sections 4.2(a) and (b), 4.4
and4.5 shall be determined by applying rules analogous to those set forth in
this definition of Profits and Losses.

         "PROPERTY" means any real, personal, tangible or intangible property
contributed to or purchased, developed or otherwise acquired and owned by the
Company, including any improvements thereto.

         "RECIPIENT" has the meaning ascribed to such term under the definition
of Discloser.

         "REGULATIONS" means the income tax regulations promulgated under the
Code, as such regulations are amended from time to time (including corresponding
provisions of succeeding regulations).

         "SEC" means the Securities and Exchange Commission of the United
States.

         "SECURITIES ACT" means the Securities Act of 1933, 15 U.S.C. "77a ET
SEQ.

         "SCIENTIFIC COMMITTEE" shall consist of equal numbers of OXiGENE and
Techniclone appointees to implement and suggest changes to the Board regarding
scientific aspects of the Plan, including implementation thereof.

         "SPONSORED RESEARCH AGREEMENT" has the meaning ascribed to such term in
Section 6.1.3.

                                      -8-
<PAGE>

         "TECHNOLOGY" means the Techniclone Contributed Technology and the
OXiGENE Contributed Technology owned or developed by the Company.

         "TECHNICLONE'S CUMULATIVE PREFERENCE" means distributions to
Techniclone pursuant to Section 5.3 (b) and (c) in the aggregate amount of
$10,000,000.

         "TECHNICLONE CONTRIBUTED TECHNOLOGY" means (excluding the Supergen and
Scotia fields of use as specified in Exhibit F) all of the proprietary rights,
technical information, technology and know-how, including inventions, patents,
copyrights, trade secrets, methods, processes, technologies, software, clinical
data, technical data and the like, trademarks (whether registered or
unregistered), trade names, service marks and certification marks, confidential
business information, and all licenses and sublicenses, applications,
registrations and renewals regarding any of the foregoing, including any
continuing developments or improvements of such information, technology and
know-how, owned or controlled (with the unconditional power to license or assign
full right, title and interest therein and thereto without the necessity of
obtaining the prior consent thereto of any other person) by Techniclone as of
the Closing Date, or developed by, for or on behalf of Techniclone thereafter,
that is used or useful in the development of VTA Technology and possibly the
creation of VTA Products, solely pursuant to the Plan; Techniclone Contributed
Technology will be effectively assigned and conveyed to the Company as of the
Closing Date pursuant to the Techniclone VTA Assignment Agreement. Techniclone
Contributed Technology includes, without limitation, an assignment to the
Company of all of the contract rights of Techniclone under the agreements
identified in Exhibit A.

         "TRANSFER" means any sale, assignment, gift, exchange, pledge,
encumbrance, change in beneficial interest of any trust or estate, distribution
from any trust or estate, change in ownership of the Members, or any other
disposition of all or any part of a Membership Interest, whether voluntary or
involuntary.

         "VTA ASSIGNMENT AGREEMENT" means the agreement assigning the
Techniclone Contributed Technology to the Company in the form of Exhibit E.

         "VTA PRODUCTS" means all products created pursuant to the application
of VTA Technology in connection with the Plan and produced, manufactured, used
or sold, for by or on behalf of the Company or any Person licensed to do so by
the Company.

         "VTA TECHNOLOGY" means vascular targeting agent technology that is
developed pursuant to the Plan, and that includes or is based upon any of the
following, or any combination thereof (including any combination with any
earlier embodiment of VTA Technology): (i) the OXiGENE Contributed Technology;
(ii) the Techniclone Contributed Technology; and (iii) any other technology
developed under, pursuant to or in connection with the Plan by, for or on behalf
of the Company or any licensee of the Company.
1.2

                                      -9-
<PAGE>

1.2 INTERPRETATION

                  (a) When required by the context, the singular includes the
plural and vice versa, and the masculine includes the feminine and neuter
genders, and vice versa;

                  (b) Except as otherwise specifically indicated, all references
in this Agreement to "Exhibits," "Schedules," "Articles," "Sections" and other
subdivisions are to the corresponding Exhibits, Schedules, Articles, Sections or
subdivisions of this Agreement as they may be amended from time to time; and

                  (c) Headings set forth in this Agreement are used for
convenience only and are not to be considered in construing or interpreting this
Agreement.

                                   ARTICLE 2

                               GENERAL PROVISIONS

2.1 NAME

         The name of the Company shall be ARCUS THERAPEUTICS LLC. All business
of the Company shall be conducted under such name and under such variations
thereof as the Board deems necessary or appropriate to comply with the
requirements of law in any jurisdiction in which the Company may elect to do
business.

2.2 PRINCIPAL PLACE OF BUSINESS; REGISTERED OFFICE AND AGENT

                  (a) The address and principal place of business of the Company
in Delaware shall be Corporation Trust Center, 1209 Orange Street, Wilmington,
DE 19801, or at such other place as the Board may from time to time determine.

                  (b) The registered office of the Company in the State of
Delaware is located at Corporation Trust Center, 1209 Orange Street, Wilmington,
DE 19801. The registered agent of the Company to accept service of process is
Corporation Trust Company.

2.3 CERTIFICATE OF FORMATION

         The Members shall form the Company under and pursuant to the Act by
filing a Certificate of Formation for the Company (the "Certificate of
Formation") with the Secretary of State of the State of Delaware.

2.4 TERM

         The term of the Company shall commence upon the filing of the
Certificate of Formation with the Secretary of State of the State of Delaware
and shall continue until dissolved in accordance with Article 14.

                                      -10-
<PAGE>

2.5 TITLE TO COMPANY PROPERTY

         The Property shall be owned solely by the Company as an entity, and no
Member, individually, shall have any ownership interest in any of the Property,
subject to the provisions of Section 14.4.

 2.6 CONFIDENTIALITY

                  (a) As used in this Agreement, the term "Confidential
Information" means all confidential or proprietary materials or information
designated as such in writing by the Discloser, whether by letter or by the use
of an appropriate proprietary stamp or legend, prior to or at the time any
confidential or proprietary materials or information are disclosed by the
Discloser or Recipient. Notwithstanding the foregoing, information or materials
which are orally or visually disclosed to the Recipient by the Discloser, or are
disclosed in writing or other tangible form without an appropriate letter,
proprietary stamp or legend, shall constitute Confidential Information if the
Discloser, within thirty (30) days after such disclosure, delivers to the
Recipient a written document or documents describing such information or
materials and referencing the place and date of such oral, visual or written or
other tangible disclosure, and the names of employees or officers of the
Recipient to whom such disclosure was made.

                  (b) The Recipient shall hold in confidence, and shall not
disclose to any Person any Confidential Information except in accordance with
the last sentence of this Section 2.6(b). The Recipient shall use such
Confidential Information only for the purpose for which it was disclosed and
shall not use or exploit such Confidential Information for its own benefit or
the benefit of another without the prior written consent of the Discloser. The
Recipient shall disclose Confidential Information received by it under this
Agreement only to those of its employees, agents and consultants, or those of an
Affiliate, who have a need to know such Confidential Information in the course
of the performance of their duties with respect to the purposes of this
Agreement and who are bound by written agreement to protect the confidentiality
of such Confidential Information in accordance with the terms hereof.

                  (c) The obligations of the Recipient specified in Section 2.6
(a) and (b) above shall not apply, and the Recipient shall have no further
obligations, with respect to any Confidential Information to the extent that
such Confidential Information:

                           (i) is generally known to the public at the time of
disclosure or becomes generally known through no wrongful act on the part of the
Recipient;

                           (ii) is in the Recipient's possession at the time of
disclosure otherwise than as a result of any prior confidential disclosure by
the Discloser or another or the Recipient's breach of any legal obligation;

                           (iii) becomes known to the Recipient through
disclosure by sources other than the Discloser having no duty of confidentiality
with respect to such Confidential Information, whether to the Discloser or
another, and having the legal right to disclose such Confidential Information;

                                      -11-
<PAGE>

                           (iv) is independently developed by the Recipient
without reference to or reliance upon the Confidential Information;

                           (v) is required to be disclosed by the Recipient to
comply with applicable laws or governmental regulations; provided, however, that
in such event, the Recipient shall provide prompt prior written notice of such
disclosure requirement to the Discloser so that Discloser may seek a protective
order or other appropriate remedy, shall take reasonable and lawful actions to
avoid and/or minimize the extent of such disclosure, shall furnish only that
portion of the Confidential Information which Recipient is advised in writing by
counsel is legally required to be disclosed and shall exercise all reasonable
efforts to obtain reliable assurance that confidential treatment will be
accorded such Confidential Information.

         The Recipient agrees that the Discloser or the Company, as the case may
be, is and shall remain the exclusive owner of the Confidential Information and
all patent, copyright, trade secret, trademark and other intellectual property
rights therein. No license or conveyance of any such rights to the Recipient is
granted or implied under this Agreement. The Company shall be and remain sole
owner of the right, title and interest in and to any invention conceived solely
by one or more Employees of the Company, regardless of the circumstances of such
conception, during the term of this Agreement. Any invention conceived jointly
by (a) one or more Employees of the Company and one or more employees of OXiGENE
and/or Techniclone or (b) one or more employees of OXiGENE together with one or
more employees of Techniclone shall be property of the Company, and the Members
will forthwith assign (or cause to be assigned) to the Company their entire
right, title and interest in and to such joint invention.

                  (d) This Section 2.6 shall supersede and cancel that part of
the letter agreement dated April 1, 2000, between OXiGENE and Techniclone,
regarding Confidential Information.

                  (e) This Section 2.6 shall survive this Agreement and shall
continue in full force and effect for a period of five (5) years after the
dissolution of the Company.

2.7 PRESS RELEASES

         2.7.1 REGARDING THIS AGREEMENT

                  Attached hereto as Exhibit H is a form of press release
concerning this Agreement and the transactions and other matters contemplated
hereby that the Members intend to release jointly, promptly following the
execution of this Agreement.

         2.7.2 REGARDING FUTURE RELEASES

                  (a) All future press releases relating to this Agreement and
the transactions and other matters contemplated hereby or related hereto shall
be made by the Company or jointly by OXiGENE and Techniclone, except that: (i)
Techniclone shall have the right to issue press releases relating to Scotia and
Supergen, subject to approval in advance by OXiGENE, notice of which shall be
sent to OXiGENE for comment or approval, a reasonable amount of time in advance
of the proposed specified date of the first publication of such press release,
which approval shall not be unreasonably withheld and which comment or approval
shall be given within the time specified in the notice to OXiGENE; provided,
however, that OXiGENE shall assume no responsibility for the accuracy or

                                      -12-
<PAGE>

completeness of any press release related to Scotia or Supergen and shall be
indemnified by Techniclone from and against any claim, loss, liability or damage
arising out of or in connection with any such press release; (ii) any press
release that, in the opinion of legal counsel to a Member, is required by law,
shall be issued; and (iii) any press release that has previously been reviewed
and released by the other Member or the Company or is in the public domain
through no fault of the releasing Member may be released by any Member. The
contents of each future press release shall be reasonable under the
circumstances.

         2.7.3 PROCEDURE

         A member who wishes to issue or have the Company issue a press release
shall prepare such release and deliver it to the other Member for approval. The
timing of such delivery shall provide the other Member a reasonable opportunity
under the circumstances to review and comment upon the proposed press release.
Subject to the proviso contained in Section 2.7.2 hereof, no press release
concerning the Company, this Agreement or the transactions and other matters
contemplated hereby or related hereto shall be issued by the Company or any
Member without the prior approval of each of the Members, which approval shall
not be unreasonably withheld.

                                    ARTICLE 3

                                     CAPITAL

3.1 CAPITAL CONTRIBUTIONS

         3.1.1 Techniclone'S CAPITAL CONTRIBUTION OF Techniclone CONTRIBUTED
               TECHNOLOGY

                  (a) Techniclone shall execute and deliver to the Company the
VTA Assignment Agreement.

                  (b) In consideration for its transfer of the Techniclone
Contributed Technology and its other promises and covenants contained herein,
Techniclone shall receive the following: (i) the fees described in Section 3.2;
and (ii) a fifty percent (50%) Membership Interest and shall have an initial
Capital Account balance equal to $30,000,000, the value of the Techniclone
Contributed Technology, as mutually agreed upon by the Members.

         3.1.2 OXiGENE CAPITAL CONTRIBUTIONS

         OXiGENE shall make cash Capital Contributions in the amounts and at the
times prescribed in the Approved Budget, which shall not in the aggregate exceed
$20,000,000. In consideration of its cash Capital Contribution, its transfer to
the Company of a license covering the OXiGENE Contributed Technology, having a
value of $30,000,000, as mutually agreed upon by the Members, and its other
promises and covenants contained herein, OXiGENE shall receive a fifty percent
(50%) Membership Interest and shall have an initial Capital Account balance of
$30,000,000. Upon OXiGENE's making each capital contribution prescribed in the
Approved Budget, OXiGENE's Capital Account Balance shall be increased in the
dollar amount of such payment.

                                      -13-
<PAGE>

         3.1.3 ADDITIONAL CAPITAL CONTRIBUTIONS

         After OXiGENE has made its cumulative Capital Contribution
under Section 3.1.2 equal to $20,000,000, any additional Capital Contribution
required as set forth in the Approved Budget shall be made in the following
manner:

                  (a) First, if the Members so agree, pro rata in proportion to
their Membership Interests;

                  (b) Second, if the Members are unable to agree to make the
additional Capital Contributions in proportion to their Membership Interests,
then the Members shall negotiate in good faith to determine the additional
Capital Contributions to be made by each Member (if any) and the effects thereof
for purposes of this agreement and the relationship between the Members.

                  (c) Any disagreement between the Members as to the effect of a
non-pro rata additional Capital Contribution which disagreement continues
unresolved for more than thirty (30) days shall be submitted for mediation
pursuant to Article 12 in the county and state in which the principal place of
business within the United States of the Member making the larger portion of the
additional Capital Contribution is located.

         3.1.4 APPROVED BUDGET; ANNUAL BUDGET

                  (a) In connection with the development of the Plan, the
Operating Committee shall recommend to the Board, and the Board shall agree
upon, an Approved Budget covering the anticipated timing and amounts of the
Company's anticipated cash needs and expenditures consistent with the Plan, as
then in effect. The initial Approved Budget shall be reviewed periodically, as
reasonably determined to be necessary or appropriate by the Members, and shall
be subject to modification as agreed upon by both Members from time to time in
the light of developments concerning the Plan and the Company.

                  (b) Ninety (90) days prior to the end of each Fiscal Year, the
Operating Committee shall adopt a new budget for the forthcoming year (each, an
"Approved Budget"). Each Approved Budget shall be prepared in accordance with
annual budgeting procedures agreed upon in the exercise of their reasonable,
good faith business judgment by the Members' delegates on the Operating
Committee, taking into account, among other things, (i) the effect on the
Company's cash requirements with respect to the Plan and the Company's other
activities, pre-clinical development expenses, laboratory and other sponsored
research expenses, drug costs (including anti-body humanization expenses),
patent fees, clinical trial costs, regulatory expenses, and patent and other
related legal expenses; (ii) the Company's requirements and prospects with
respect to the development and exploitation of the VTA Technology and the
creation, production, marketing and sale of VTA Products; and (iii) furthering
the Company's stated purpose.

                                      -14-
<PAGE>

                  (c) The Operating Committee shall consist of an equal number
of delegates appointed by each Member. The Operating Committee shall be operated
under rules consistent with Section 6.2 and Section 6.5, consistent with the
Plan, as in effect from time to time.

                  (d) The Company shall expend its funds and other resources
only in a manner that is consistent with the Approved Budget.

                  (e) Each Member shall bear its own internal general and
administrative overhead costs, which costs shall not be allocated to the
Company.

3.2 PAYMENTS TO Techniclone

         In addition to the Capital Contributions described in Section 3.1.2,
OXiGENE shall make payments to Techniclone as follows:

                  (a) THE INITIAL LICENSING FEE. OXiGENE will pay to Techniclone
within three (3) days of the Closing Date the Initial Licensing Fee, of which
$2,000,000 will be applied towards the purchase of a number of shares of
Techniclone's unregistered common stock derived by dividing such $2,000,000 by
the average closing price on the NASDAQ National Market of Techniclone's common
stock for the five (5) trading days immediately prior and the five (5) trading
days immediately subsequent to the Closing Date (the "Initial Techniclone
Shares"), and $1,000,000 of which will be a non-refundable licensing fee.

                  (b) THE ADDITIONAL LICENSING/MILESTONE FEE. OXiGENE will pay
to Techniclone within three (3) days of the filing of the Company's first IND
that relates to a drug developed pursuant to the Plan, the Additional
Licensing/Milestone Fee, of which $1,000,000 will be applied towards the
purchase of an additional number of shares of Techniclone's unregistered common
stock derived by dividing such $1,000,000 by the average closing price on the
Nasdaq National Market of Techniclone's common stock for the five (5) trading
days immediately prior to and the five (5) days immediately subsequent to the
filing with the Food and Drug Administration of such IND (the "Additional
Techniclone Shares") and $1,000,000 of which will be a non-refundable licensing
fee.

3.3 NO WITHDRAWAL OF CAPITAL; NO INTEREST ON CAPITAL

         No Member shall be entitled to withdraw or demand the return of any
part of such Member's Capital Contributions, except as provided in Article 5 and
Article 14. No Member shall have the right to receive interest on its Capital
Contribution or its Capital Account.

                                   ARTICLE 4

                         ALLOCATIONS AND TAX PROVISIONS

4.1 MAINTENANCE OF CAPITAL ACCOUNTS

         A Capital Account shall be established and maintained for each Member
in accordance with the following provisions:

                                      -15-
<PAGE>

                  (a) Each Member's Capital Account shall be increased by (i)
the amount of such Member's Capital Contribution, (ii) such Member's allocable
share of Profits and any items of the nature of income or gain that are
specially allocated pursuant to Sections 4.2(a) or (b), 4.4 or 4.5, and (iii)
the amount of any Company liabilities assumed by such Member or that are secured
by any Property distributed to such Member.

                  (b) Each Member's Capital Account shall be decreased by (i)
the amount of cash and the Gross Asset Value of any Property distributed to such
Member pursuant to any provision of this Agreement, (ii) such Member's
distributable share of Losses and any items in the nature of expenses or losses
that are specially allocated pursuant to Sections 4.3, 4.4 or 4.5, and (iii) the
amount of any liabilities of such Member assumed by the Company or that are
secured by any property contributed by such Member to the Company.

                  (c) Upon the Transfer of all or part of an Interest, the
Capital Account of the transferor that is attributable to the transferred
Interest shall carry over to the transferee Member in accordance with the
provisions of Regulations Section 1.704-l(b)(2)(iv)(1), except as otherwise
required to satisfy Regulations Section 1.704-l(b) in connection with a
termination of the Company.

                  (d) In determining the amount of any liability for purposes of
maintaining Capital Accounts for the Members, there shall be taken into account
Code Section 752(c) and any other applicable provisions of the Code and the
Regulations. In the event the Board shall determine that it is prudent to modify
the manner in which the Capital Accounts, or any debits or credits thereto
(including, without limitation, debits or credits relating to liabilities that
are secured by contributed or distributed property or that are assumed by the
Company or the Members), are computed in order to comply with the Code and the
Regulations, the Board may make such modification, provided that it is not
likely to have any material effect on the amounts distributable to any Member
pursuant to Article 14 upon the dissolution of the Company. The Board also shall
make (i) any adjustments that are necessary or appropriate to maintain equality
between (a) the Capital Accounts of the Members and (b) the amount of Company
capital reflected on the Company's balance sheet, as computed for book purposes,
in accordance with Regulations Section 1.704-1(b)(2)(iv)(g) and (ii) any
appropriate modifications in the event unanticipated events might otherwise
cause this Agreement not to comply with Regulations Section 1.704-1(b).

4.2 ALLOCATIONS OF PROFITS

         After giving effect to the special allocations set forth in Sections
4.4 and 4.5, Profits or items thereof for any Fiscal Year shall be allocated
among the Members in the following manner:

                  (a) First, Profits (or items thereof) to Techniclone in the
amount of any distributions made by the Company during the year under Section
5.3 (a).

                  (b) Second, Profits (or items thereof) to Techniclone in the
amount of any distributions made by the Company during the year under Section
5.3 (b).

                                      -16-
<PAGE>

                  (c) Third, to the Members in proportion to and in the amount
of any distributions made by the Company during the year under Section 5.3(c).

                  (d) Fourth, to the Members in proportion to and in the amount
of any distributions made by the Company during the year under Section 5.3(d).

                  (e) Fifth, Profits equal to Losses (or items of deduction)
previously allocated pursuant to Section 4.3 shall be allocated to the Members
who received such Loss allocations in proportion to and in the amount of such
prior allocation (reduced by previous allocations of Profits under this Section
4.2(e).)

                  (f) Thereafter, all remaining Profits shall be allocated to
the Members in proportion to their respective Membership Interests.

4.3 ALLOCATION OF LOSSES AND DEDUCTIONS

         4.3.1 The Company shall allocate to OXiGENE cumulative losses and items
of deduction equal to the cumulative cash capital contributions actually made by
OXiGENE under section 3.1.2.

         4.3.2 The Company next shall allocate to the Members contributing
additional Capital Contributions under Section 3.1.3 any Losses in proportion to
the additional Capital Contributions made by each Member, up to the amount of
such additional Capital Contributions.

         4.3.3 After giving effect to the special allocations set forth in this
Section 4.3 and Sections 4.4 and 4.5, Losses for any Fiscal Year shall be
allocated among the Members in proportion to their respective Membership
Interests.

4.4 SPECIAL ALLOCATIONS

         The following special allocations shall be made in the following order
and priority:

         4.4.1 MINIMUM GAIN CHARGEBACK AND QUALIFIED INCOME OFFSET

         No Member shall be allocated Losses or deductions if the allocation
causes the Member to have an Adjusted Capital Account Deficit; in such event,
such items shall be allocated to the other Members. If a Member for any reason
(whether or not expected) receives (1) an allocation of Loss or deduction (or
item thereof) or (2) any Distribution, which causes the Member to have an
Adjusted Capital Account Deficit at the end of any taxable year, then all items
of income and gain of the Company (consisting of a pro rata portion of each item
of Company income, including gross income and gain) for that taxable year shall
be allocated to that Member, before any other allocation is made of Company
items of Profit or Loss for that taxable year (other than an allocation under
Section 4.4.2), in the amount and in proportions required to eliminate the
excess as quickly as possible. This Section 4.4.1 is intended to comply with,
and shall be interpreted consistently with, the "alternate test for economic
effect" and "qualified income offset" provisions of the Regulations promulgated
under Code Section 704(b).

                                      -17-
<PAGE>

         4.4.2 MINIMUM GAIN CHARGEBACKS

         In order to comply with the "minimum gain chargeback" requirements of
Regulation Sections 1.704-2(f)(1) and 1.704-2(i)(4), and notwithstanding any
other provision of this Agreement to the contrary, in the event there is a net
decrease in a Member's share of Minimum Gain and Member Nonrecourse Debt Minimum
Gain during a taxable year of the Company, such Member shall be allocated items
of income and gain for that year (and if necessary, other years) as required by
and in accordance with Regulation Sections 1.704-2(f)(1) and 1.704-2(i)(4)
before any other allocation is made. It is the intent of the parties hereto that
any allocation pursuant to this Section 4.4.2 shall constitute a "minimum gain
chargeback" under Regulation Section 1.704-2(f) and 1.704-2(i)(4).

         4.4.3 CONTRIBUTED PROPERTY AND BOOK-UPS

         In accordance with Code Section 704(c) and the Regulations thereunder,
including Regulation Section 1.704-1(b)(2)(iv)(d)(3), income, gain, loss, and
deduction with respect to any property contributed (or demand contributed) to
the Company shall, solely for tax purposes, be allocated among the Members so as
to take into account any variation between the adjusted basis of the property to
the Company for federal income tax purposes and its fair market value at the
date of Contribution (or deemed Contribution). If the adjusted book value of any
Company asset is adjusted under Regulation Section 1.704-1(b)(2)(iv)(f),
subsequent allocations of income, gain, loss, and deduction with respect to the
asset shall take into account any variation between the adjusted basis of the
asset for federal income tax purposes and its adjusted book value in the manner
required under Code Section 704(c) and the Regulations thereunder. The Board
shall select a method as described in Regulation 1.704-3 for making Section
704(c) allocations.

         4.4.4 NONRECOURSE DEDUCTIONS

         Nonrecourse Deductions for any Fiscal Year shall be specially allocated
among the Members in proportion to their Membership Interests.

         4.4.5 MEMBER NONRECOURSE DEDUCTIONS

         Any Member Nonrecourse Deductions for any Fiscal Year shall be
specially allocated to the Member who bears the economic risk of loss with
respect to the Nonrecourse Debt to which such Member Nonrecourse Deductions are
attributable in accordance with Regulations Section 1.704-2(i)(1).

         4.4.6 CODE SECTION 754 ADJUSTMENTS

         To the extent an adjustment to the adjusted tax basis of any Company
asset pursuant to Code Section 734(b) or Code Section 743(b) is required
pursuant to Regulations Section 1.704-1(b)(2)(iv)(m)(2) or Section
1.704-1(b)(2)(iv)(m)(4) to be taken into account in determining Capital Accounts
as a result of a distribution to a Member in complete liquidation of its
Interest, the amount of such adjustment to Capital Accounts shall be treated as
an item of gain (if the adjustment increases the basis of the asset) or loss (if
the adjustment decreases the basis of the asset) and such gain or loss shall be
specially allocated to the Members in accordance with their interests in the
Company in the event Regulations Section 1.704-1(b)(2)(iv)(m)(2) applies, or to
the Member to whom such distribution was made in the event Regulations Section
1.704-1(b)(2)(iv)(m)(4) applies.

                                      -18-
<PAGE>

         4.4.7 ALLOCATIONS RELATING TO TAXABLE ISSUANCE OF INTERESTS

         Income, gain, loss or deduction, if any, realized by the Company as a
direct or indirect result of the issuance of an Interest by the Company to a
Member (the "Issuance Items") shall be allocated among the Members so that, to
the extent possible, the Capital Account balance for each Member for any Fiscal
Year is equal to the Capital Account balance that would have been maintained for
such Member for such Fiscal Year had the Company not realized the Issuance
Items.

4.5 OTHER ALLOCATIONS RULES

                  (a) For purposes of determining the Profits, Losses or any
other items allocable to any period, Profits, Losses and any such other items
shall be determined on a daily, monthly or other basis, as determined by the
Board using any permissible method under Code Section 706 and the Regulations
thereunder.

                  (b) Except as otherwise provided in Section 4.6 with respect
to allocations pursuant to Code Section 704(c), for federal income tax purposes,
all items of Company income, gain, loss or deduction shall be made in a manner
that is consistent with the allocation of Profits and Losses pursuant to this
Article 4. The Members are aware of the income tax consequences of the
allocations of this Article 4 and hereby agree to be bound by the provisions of
this Article 4 in reporting their allocable shares of Company income and loss
for income tax purposes.

                  (c) Solely for purposes of determining a Member's
proportionate share of the "excess nonrecourse liabilities" of the Company
within the meaning of Regulations Section 1.752- 3(a)(3), the Members' interests
in Company profits shall be equal to their respective Membership Interests.

4.6 TAX MATTERS MEMBER

                  (a) Techniclone shall be the "tax matters partner" (the "Tax
Matters Member") for the Company within the meaning of Code Section 6231(a)(7).

                  (b) The Tax Matters Member shall notify and provide copies to
the other Members within five (5) business days (or as soon as reasonably
practicable thereafter) of any communication received from any governmental
authority regarding any proposed or existing audit, administrative or judicial
proceeding, request for information, preliminary discussion or any other formal
or informal communication regarding any tax matters pertaining to the Company or
any Member. In addition to and not in limitation of the foregoing, the Tax
Matters Member shall request, pursuant to Code Section 6223, that the other
Members receive notice from the IRS regarding any proceedings or adjustments.
The Tax Matters Member shall consult with the other Members concerning all tax
matters and shall not take any action in connection with any audit or
proceeding, or enter into any agreement with the IRS, that may adversely affect
the other Members without their express prior written consent.

                  (c) The Tax Matters Member shall, upon request of a Member,
make an election under Code Section 754 and the applicable regulations
thereunder.

                                      -19-
<PAGE>

                                   ARTICLE 5

                                  DISTRIBUTIONS

5.1 DISTRIBUTIONS; GENERAL

         The Board shall cause the Company to distribute, no less frequently
than annually, all of the Net Cash From Operations of the Company and any
special distributions required under Section 5.3

5.2 ADDITIONAL LIMITATIONS ON DISTRIBUTIONS

         No distribution shall be made if it would render the Company insolvent
or compromise its ability to operate, giving consideration to OXiGENE's required
Capital Contributions. Further, the Board shall not distribute any Property in
kind except upon liquidation of the Company.

5.3 DISTRIBUTIONS TO MEMBERS

                  (a) All licensing fees (which term does not include royalties)
and milestone payments received by the Company, whether in cash or in kind,
derived pursuant to Techniclone's agreements with Scotia and Supergen, shall be
distributed to Techniclone in the form received by the Company. All royalties
(other than licensing fees and milestone payments) received by the Company,
whether in cash or kind, derived pursuant to Techniclone's agreements with
Scotia and Supergen shall be included in Net Cash From Operations and shall be
determined, allocated and distributed in the form received by the Company
pursuant to Section 5.3(c).

                  (b) Subject to the first sentence of Section 5.3(a), all
revenues derived from Pending Matters (after deducting such expenses associated
with the production of such revenues as are reasonably established by
Techniclone in connection with the preparation of its financial statements in
accordance with GAAP consistently applied) shall be distributed to Techniclone
(and shall be credited against the Techniclone Cumulative Preference).

                  (c) All remaining Net Cash From Operations of the Company
shall be distributed in the following manner; (i) until Techniclone has received
cumulative distributions under Section 5.3(b) and this 5.3(c) equal to the
Techniclone Cumulative Preference, 75% to Techniclone and 25% to OXiGENE; and
(ii) after Techniclone has received aggregate distributions equal to the
Techniclone Cumulative Preference, to each Member in accordance with its
Membership Interests.

                  (d) Notwithstanding Section 5.3(c), upon the occurrence of an
Early Termination Event, prior to any distribution under Section 5.3(c), Net
Cash From Operations equal to the Early Termination Preference shall be
distributed to Techniclone and the Early Termination Remainder (or the remainder
after payment to Techniclone of its Applicable Percentage in Paragraph (B) of
the definition of Early Termination Preference shall apply) shall be distributed
to OXiGENE, each to the extent and in the amount applicable.

                                      -20-
<PAGE>

                                   ARTICLE 6

                            MANAGEMENT AND OPERATION

6.1 MANAGEMENT OF THE COMPANY

         6.1.1 MANAGERS

         The Members hereby agree that the business, property and affairs of the
Company shall be managed exclusively by a board of Managers (the "Board"), which
shall be constituted as set forth in Section 6.2. Except for situations in which
the direct approval of the Members is expressly required by this Agreement or
the Act, the Board shall have full, complete and exclusive authority, power and
discretion to manage and control the business, property and affairs of the
Company, to make all decisions regarding those matters and to perform or cause
to be performed any and all other acts or activities customary or incident to
the management of the Company's business, property and affairs. The Board may
delegate such of its duties to one or more committees as the Board may establish
with the approval of all the persons who are then sitting on the Board.

         6.1.2 MEMBERS

         The Members shall only have the power to participate in the management
of the Company as expressly authorized by this Agreement or the Act. No Member,
acting solely in such capacity, is, or shall hold itself out as being, an agent
of the Company. Unless expressly and duly authorized in writing to do so by the
Board, no Member shall have any power or authority to bind or act on behalf of
the Company in any way, to pledge its credit, to execute any instrument on its
behalf or to render it liable for any purpose.

         6.1.3 COMPANY CONTRACTUAL OBLIGATIONS

                  (a) Within sixty (60) days after the Closing Date, the Company
will agree to terms, to be set forth in a definitive agreement, with the
University of Texas and Dr. Philip Thorpe with respect to the research to be
conducted by the University of Texas and Dr. Thorpe for or on behalf of the
Company and the funding of such research by the Company. Such definitive
agreement (the "SPONSORED RESEARCH AGREEMENT") shall be in the form of either a
new agreement between and among the Company or Techniclone, on the one hand, and
the University of Texas and Dr. Thorpe, on the other hand, or a modification of
the existing agreement between and among Techniclone, the University of Texas
and Dr. Thorpe (a copy of which is attached hereto as Exhibit G; the
"TEXAS/THORPE Agreement"). If the Company is not a party to the Sponsored
Research Agreement, Techniclone shall promptly assign its rights, subject to its
obligations, under the Sponsored Research Agreement to the Company (such
assignment to be in such form as the Company may reasonably require). The
Sponsored Research Agreement, whether a new agreement or a modification of the
Texas/Thorpe Agreement, shall contain all the terms and conditions that are
currently contained in the Texas/Thorpe Agreement, provided however, that the
amount and timing of funding shall be as set forth in the Approved Budget.

                                      -21-
<PAGE>

                  (b) In addition to the Sponsored Research Agreement,
Techniclone shall have the right to enter into one or more agreements with the
University of Texas and/or Dr. Thorpe to conduct research outside the Field. The
Company's rights and obligations under the Sponsored Research Agreement shall
represent the first priority for the use by the Company, the Members and their
affiliates of the services of the University of Texas and Dr. Philip Thorpe.
Techniclone has and will continue to have the right to enter into one or more
agreements with the University of Texas and Dr. Philip Thorpe to conduct
research outside the Field provided that such research does not directly involve
the Field and does not adversely affect the ability of the University of Texas
or Dr. Philip Thorpe to perform the services required of either or both of them
under the Sponsored Research Agreement. The Board shall have the authority to
determine whether research or other activities referred to in the preceding
sentence are outside the Field.

6.2 MANAGEMENT

         6.2.1 The Board shall have four (4) Managers, two (2) of whom shall be
designated by OXiGENE (the "OXiGENE Managers") and two (2) of whom shall be
designated by Techniclone (the "Techniclone Managers"). OXiGENE may remove any
OXiGENE Manager or fill any vacancy created by the removal, resignation, death
or disability of an OXiGENE Manager and determine the effective date of such
replacement. Techniclone may remove any Techniclone Manager or fill any vacancy
created by the removal, resignation, death or disability of a Techniclone
Manager and determine the effective date of such replacement. The number of
Managers shall not be decreased or increased without the unanimous written
consent of the Members. The Board shall appoint one Manager to serve as Chair,
who shall serve in such capacity for a term of two (2) years. The Board shall
attempt to alternate between appointing an OXiGENE Manager and a Techniclone
Manager as Chair in each succeeding term; provided, however, a Manager may serve
consecutive terms if so appointed by the Board.

         6.2.2 Each Manager shall sign an addendum to this Agreement agreeing to
be bound by its terms.

         6.2.3 In the event of a disagreement between the OXiGENE Managers and
the Techniclone Managers, (x) OXiGENE shall have the tie-breaking vote with
respect to (i) development activities, including without limitation a decision
to abandon the Plan, and (ii) any sublicense agreements, in either case, that
directly involve the Plan or its administration by the Company, and (y)
Techniclone shall have the tie-breaking vote with respect to any sublicense
agreements related to Pending Matters or to any other sublicense not directly
related to the Plan.

         6.2.4 Subject to the foregoing, Techniclone shall have complete
authority to negotiate and enter into sublicensing contracts in connection with
any Pending Matters.

                                      -22-
<PAGE>

6.3 PERFORMANCE OF DUTIES

         Each Manager shall perform his or her managerial duties in good faith,
in a manner he or she reasonably believes to be in the best interests of the
Company and its Members, and with such care, including reasonable inquiry, as an
ordinarily prudent person in a like position would use under similar
circumstances. In performing his or her duties, the Managers shall be entitled
to rely on information, opinions, reports, or statements, including financial
statements and other financial data, of the following persons or groups, unless
they have knowledge concerning the matter in question that would cause such
reliance to be unwarranted and provided that the Manager acts in good faith and
after reasonable inquiry when the need therefor is indicated by the
circumstances:

                  (a) one or more officers, employees or other agents of the
Company or a Member whom the Manager reasonably believes to be reliable and
competent in the matters presented; or

                  (b) any attorney, independent accountant or other person as to
matters that the Manager reasonably believes to be within such person's
professional or expert competence.

6.4 DEVOTION OF TIME

         A Manager is not obligated to devote all of his or her time or business
efforts to the affairs of the Company. A Manager shall devote whatever time,
effort and skill as he or she deems appropriate for the operation of the
Company.

6.5 MEETINGS OF THE BOARD

         The Board shall meet at least once every quarter. In addition, the
Board shall meet upon the request of any Manager made to the Chair. Managers may
participate in meetings by means of audio or video conferencing equipment
through which all Managers participating in the meeting can hear each other at
the same time, and participation by such means shall constitute presence in
person at a meeting. Meetings shall be held at such place and time as agreed to
by the Board. The Chair shall provide at least five (5) business days' advance
written notice and an agenda of each meeting of the Board to each Manager,
unless a Manager waives the advance notice requirement with respect to that
Manager. Records of proceedings of the Board shall be prepared by the Chair and
shall be subject to the approval of the Board.

         6.5.1 Regular meetings of the Board may be held at any place that has
been designated from time to time by resolution of the Board. In the absence of
such a designation, regular meetings shall be held in alternating years at the
principal executive office of one of the Members. Special meetings of the Board
may be held at any place that has been designated in the notice of the meeting
or, if not stated in the notice or if there is no notice, at the principal
executive office of one of the Members (which location shall alternate from
special meeting to special meeting, starting with Techniclone).

         Members of the Board may participate in a meeting through the use of
conference telephone or similar communications equipment, so long as all
directors participating in such meeting can hear one another. Participation in a
meeting pursuant to this paragraph constitutes presence in person at such
meeting.

         6.5.2 Regular meetings of the Board may be held without notice if the
time and place of such meetings are fixed by the Board.

                                      -23-
<PAGE>

         6.5.3 Subject to the provisions of the following paragraph, special
meetings of the Board for any purpose or purposes may be called at any time by
any three Managers.

         Notice of the time and place of special meetings shall be delivered
personally, by e-mail or by telephone to each Member or sent by first-class mail
or by telecopier, addressed to each Member at that Member's address as it is
shown on the records of the Company. If the notice is mailed, it shall be
deposited in the United States mail at least four (4) days before the time of
the holding of the meeting. If the notice is delivered personally or by
telephone or by telecopier or by e-mail, it shall be delivered personally or by
telephone or by telecopier at least forty-eight (48) hours before the time of
the holding of the meeting. Any oral notice given personally or by telephone may
be communicated either to the director or to a person at the office of the
director who the person giving the notice has reason to believe will promptly
communicate it to the Manager. The notice shall specify the purpose of the
special meeting.

         6.5.4 Notice of a meeting need not be given to any Manager who signs a
waiver of notice or a consent to holding the meeting or an approval of the
minutes thereof, whether before or after the meeting, or who attends the meeting
without protesting, prior thereto or at its commencement, the lack of notice to
such Manager. All such waivers, consents, and approvals shall be filed with the
Company's records or made a part of the minutes of the meeting. A waiver of
notice need not specify the purpose of any regular or special meeting of the
Board.

         6.5.5 A majority of the Members present, whether or not a quorum is
present, may adjourn any meeting to another time and place.

         6.5.6 If the meeting is adjourned for more than twenty-four (24)
hours, notice of any adjournment to another time and place shall be given prior
to the time of the adjourned meeting to the Members who were not present at the
time of the adjournment.

         6.5.7 Any action required or permitted to be taken by the Board may
be taken without a meeting, if all members of the Board individually or
collectively consent in writing to such action. Such written consent or consents
shall be filed with the minutes of the proceedings of the Board. Such action by
written consent shall have the same force and effect as a unanimous vote of the
Board.

         6.5.8 If a quorum is present at a meeting but fewer than all the
Managers designated by a Member are present at such meeting, the Managers
designated by such Member who are present shall be entitled to cast the number
of votes at such meeting that could have been cast by all the Managers
designated by such Member had all such Managers been present at such meeting.

6.6 QUORUM AND VOTING AT MEETINGS OF MANAGERS

                  (a) QUORUM. One Techniclone member and one OXiGENE member
shall constitute a quorum of the Board for the transaction of business.

                  (b) VOTING. Except as provided in Sections 6.5.8 and 6.6(c),
any management decision shall require the approval of the Board, which approval
shall exist only upon the affirmative vote of two (2) or more Managers at a
meeting of the Board at which a quorum is present.

                                      -24-
<PAGE>

                  (C) MEMBERS' CONSENT. The following actions shall require both
the approval of the Board and the unanimous written consent of the Members:

                           (i) The entry by the Company into any business
outside the development and sale of the Technology or in a manner inconsistent
with the Plan; and

                           (ii) Any act in material contravention of this
Agreement.

6.7 OFFICERS; COMMITTEES

         The Board may, but is not required to, establish officers of the
Company and prescribe the duties of such officers. The officers of the Company
shall be chosen by, and shall serve at the pleasure of, the Board, and shall
hold their respective offices until their resignation, removal, or other
disqualification from service in a manner determined by the Board, or until
their respective successors shall be elected. The Board may, but is not required
to, establish such teams or committees composed of representatives from the
Members or otherwise and delegate to such teams or committees such authority,
duties and responsibilities as it deems appropriate. To assist the Board in
managing the Company, the Board shall establish an Operating Committee and a
Scientific Committee composed of individuals who shall serve for one (1) year
terms each, subject to reappointment by the Board. The Operating Committee shall
perform such functions as directed by the Board. The Board shall prescribe the
duties, responsibilities, operating procedures and deadlines for each such
Committee.

6.8 INTERNAL CONTROLS

         The Board shall conduct the business of the Company at all times in
accordance with high standards of business ethics and devise and maintain a
system of internal accounting controls sufficient to provide reasonable
assurances that (a) transactions are executed in accordance with management's
general or specific authorization; (b) transactions are recorded as necessary to
permit preparation by the Company, OXiGENE and Techniclone of financial
statements in conformity with U.S. generally accepted accounting principles, to
permit preparation of all tax returns and to maintain accountability for assets
as set forth in Section 15.1; and (c) access to assets is permitted only in
accordance with management's general or specific authorization.

6.9 FINANCIAL AND BUSINESS INFORMATION AND TAX RETURNS

         The Board shall make available to all the Members on a regular basis,
and as reasonably requested, all such information and/or documents (including
Business Documents as defined in Section 6.6(c)(iii)) as may be required to
permit the Board and the Members, as the case may be, to make informed judgments
with respect to all matters concerning the Company of interest to them.

                                      -25-
<PAGE>

6.10 BANK ACCOUNTS

         All funds of the Company shall be deposited in the name of the Company
in such bank accounts as shall be determined by the Board. No withdrawals for
cash may be made in excess of $100,000 at any one time without Board approval.
Any payment from the accounts may be made or authorized only by an individual
who is so authorized by the Board. The funds of the Company shall not be
commingled with the funds of any other Person, and the Board shall not employ,
or permit any other Person to employ, such funds in any manner except for the
benefit of the Company. The Members shall not make deposits into or issue any
checks against the Company bank accounts without full, proper and complete
supporting records.

6.11 INDEPENDENT ENTERPRISE

         The Members agree to cause the Company at all times to be conducted as
an enterprise for profit. Except as otherwise agreed to by the Members in
writing or provided herein, all commercial transactions between the Company and
OXiGENE and/or Techniclone (or their Affiliates) shall be conducted on an
arm's-length basis with neither granting to the other terms or conditions more
favorable than would be accorded unrelated third parties, except as the Members
otherwise agree in writing prior to any such transaction.

6.12 COMPENSATION

         No Manager shall be entitled to compensation from the Company for
services rendered to the Company as Manager, except that the Company shall
reimburse each Manager for reasonable out-of-pocket expenses incurred by the
Manager in connection with the Company's business. The previous sentence,
however, shall not preclude any Manager from serving the Company in any other
capacity and receiving compensation therefor.

6.13 FIDUCIARY DUTY

         Each Member, Manager and officer shall all have the fiduciary
responsibility for the safekeeping and use of all funds and assets (including
records) of the Company, whether or not in immediate possession or control, for
the exclusive benefit of the Company and its Members.

6.14 OTHER ACTIVITIES

         The Members may engage in or possess an interest in other business
ventures of any nature or description, independently or with others, whether
presently existing or hereafter created, other than those that are reasonably
within the scope of the Plan.

6.15 NONCOMPETITION

                  (a) GENERAL. Until dissolution of the Company in accordance
with Article 14 or purchase of the Member's Interest in accordance with this
Agreement, no Member shall, and each Member shall cause its Affiliates not to,
develop, license, research or sell the Technology other than in accordance with
the Plan and this Agreement.

                                      -26-
<PAGE>

                  (b) EXCEPTIONS. Section 6.15(a) shall not apply to any PENDING
MATTER.

6.16 CONFLICTS OF INTEREST

         The Managers who represent any Member referred to in Section 6.2 (the
"Interested Member") shall not be entitled to vote on any matter that involves
(a) a claim by the Company against the Interested Member or an Affiliate of the
Interested Member; (b) a claim by the Interested Member or its Affiliate against
the Company; (c) the declaration by the Company of a default under any agreement
between the Company and the Interested Member or its Affiliate; (d) the exercise
by the Company of any right to terminate any agreement between the Company and
the Interested Member or its Affiliate based on a default thereunder; (e) the
negotiation of any new agreements to be entered into by the Company and such
Interested Member or its Affiliate; or (f) any and all disputes between the
Company and the Interested Member or its Affiliate. As to matters where the
representatives of a Member are not entitled to vote, the representatives of the
other Member who are not disqualified may exercise the powers of the Board in
accordance with, and subject to the other provisions of, this Agreement.
Notwithstanding the foregoing, however, no claim shall be asserted by the
Company or by an Interested Member (or its Affiliate) against the other, and no
default shall be declared by the Company or an Interested Member (or its
Affiliate) with respect to the other, unless such claim or dispute cannot be
resolved either by the approval of the Board as provided under Section 6.6 or
under Article 12.

6.17 PATENTS

         The Company will seek patent protection for any Company Discovery or
other patentable information developed by the Company pursuant to the Plan, as
to which the Board, upon recommendation of the Scientific Committee, determines
such protection is necessary or desirable in order to further the Company's
purposes and/or enhance or protect the Company's economic return. Company
Discoveries of any type created or perfected pursuant to the Plan shall be the
property of the Company until the liquidation and termination of the Company.

6.18 TRADEMARKS

         At or shortly after formation each of the Members will grant the
Company a nonexclusive, royalty free, worldwide license to use the Member's name
and logo in the name of the Company and with the Company's products, product
literature (including promotional materials) and services, subject to the terms
of reasonable trademark licenses to be negotiated in good faith.

                                      -27-
<PAGE>

                                   ARTICLE 7

                  RIGHTS, OBLIGATIONS AND POWERS OF THE MEMBERS

7.1 COMPENSATION OF MEMBERS

         Except as may be specifically provided in this Agreement or in any
other written agreement between the Company and the Member, no Member shall
receive any salary, fee or draw for services rendered to or on behalf of the
Company.

7.2 SERVICES

         7.2.1 TYPES OF SERVICES

                  (a) Initially, OXiGENE and its Affiliates are expected to
provide the Company with business management, accounting and financial support
services in connection with the daily operation of the Company's business. Both
Members or their Affiliates are expected to provide the Company with legal
advice and related support services in connection with filing of patent
applications, protection of intellectual property and support of litigation
related to intellectual property matters and with such other services as the
Company may require and the Members may agree to provide. The foregoing services
that are expected to be provided to the Company shall be subject to the terms of
reasonable service agreements to be negotiated in good faith.

                  (b) OXiGENE agrees to use its commercially reasonable best
efforts, consistent with pharmaceutical industry standards and OXiGENE's
customary practices in connection with similar matters on its own behalf, to
enable and cause the Company to file an IND for a therapeutic agent based on and
deriving from the VTA Technology and coming within the framework of the Plan
within thirty-six (36) months of the Closing Date, which period shall
automatically be extended (i) for an additional period of 18 months if, at the
end of such 36-month period, OXiGENE is, in good faith and in a manner
consistent with pharmaceutical industry standards and OXiGENE's customary
practice in connection with similar matters on its own behalf, working towards
the filing of such an IND and (ii) on a day-by-day basis for every day that the
failure of OXiGENE to file such IND results substantially from a matter that is
within the control of Techniclone.

         7.2.2 CHARGES FOR SERVICES

         Services supplied to the Company by any Member may be charged on the
following basis and shall be paid by the Company within 30 days of submission to
the Company of the statement of expenses for such services by the Member seeking
reimbursement thereof:

                  (a) Each Member may charge the Company for actual expenses
incurred, including an allocable portion of payroll and reimbursed employee
business expenses, in connection with the actual time spent on Company business
by employees of the member. Any employee of a Member working on Company business
shall maintain detailed time records, in hourly increments, setting forth the
identity and nature of the Company's project and specific activities performed
and a summary of such time records shall be submitted by the Member to the
Company as a prerequisite to reimbursement. If such a summary is provided, the
actual records of the Member from which that summary were derived shall be made
available upon request to the other Member at reasonable times and places.

                                      -28-
<PAGE>

                  (b) If a Member retains a third party to provide consulting or
other services to the Company, the Member may charge the Company for providing
such services in the amount that the third party charges the Member, provided
such charges are reasonable.

                  (c) Each Member will submit charges for its employees' actual
time expended in projects for the Company based on their actual hourly
compensation, including the employer's share of FICA and similar employment
taxes, for work performed for the Member, but not including indirect costs and
overhead. Such charges shall not exceed industry norms for projects of such or
similar type.

                  (d) Any delegate to the Operating Committee may request copies
of the time records required by Section 7.2.2(a).

7.3 ADMISSION OF ADDITIONAL MEMBERS

         The Board may admit to the Company additional Members, from time to
time, subject to the following:

                  (a) All the Members agree in writing to the admission of the
new Member;

                  (b) The additional Member shall make a Capital Contribution in
such amount and on such terms as the Board determines to be appropriate; and

                  (c) No additional Member shall be admitted if the effect of
such admission would be to terminate the Company within the meaning of Code
Section 708(b).

                                   ARTICLE 8

                   LIMITATION UPON LIABILITY; INDEMNIFICATION

8.1 LIMITATION UPON LIABILITY

         No Member, Manager, officer or Affiliate thereof shall be liable,
responsible or accountable for damages or otherwise to the Company for any act
or omission by a Member, Manager, officer or Affiliate thereof performed in good
faith and in a manner reasonably believed by him, her or it to be within his,
her or its scope of authority granted by this Agreement and in the best interest
of the Company. The Member, Manager or Officer shall be liable, however, for an
act or omission that constitutes fraud, intentional misconduct, bad faith, gross
negligence or a knowing violation of law. The liability of the Members,
Managers, officers or Affiliates shall be further limited as set forth in the
Act and other applicable law. Any repeal or modification of this Section 8.1
shall not adversely affect any right or protection of a Member, Manager, officer
or Affiliate thereof existing at the time of such repeal or modification.

                                      -29-
<PAGE>

8.2 COMPANY'S DEBTS

         The debts, obligations and liabilities of the Company, whether arising
in contract, tort or otherwise (except for the Member's, Manager's or officer's
own torts), shall be solely the debts, obligations and liabilities of the
Company; and no Member, Manager or officer shall be obligated personally for any
such debts, obligations and liabilities of the Company solely by reason of being
a Member or acting as a Manager or officer of the Company.

8.3 MEMBER'S DEBTS

         The personal debts, obligations and liabilities of any Member, Manager,
officer or Affiliate thereof, whether arising in contract, tort or otherwise,
shall be solely the personal debts, obligations and liabilities of such Member,
Manager, officer or Affiliate and the Company shall not be obligated for such
debts, obligations or liabilities.

8.4 FAILURE TO OBSERVE FORMALITIES

         A failure to observe any formalities or requirements of this Agreement,
the Certificate of Formation or the Act shall not be grounds for imposing
personal liability on the Members, Managers or officers for liabilities of the
Company.

8.5 INDEMNIFICATION

         To the maximum extent and manner permitted under Section 18-108 of the
Act, the Company shall indemnify and hold harmless all Members, Managers,
officers, employees, their Affiliates and authorized agents of the Company (an
"indemnitee") against any liability, loss, damage, cost or expense (including
attorneys' fees and costs) actually and reasonably incurred by an indemnitee by
reason of the fact that the Person is or was a Member, Manager, officer,
employee or Affiliate thereof; provided, however, that the Company shall not
indemnify and hold harmless an indemnitee in any of the circumstances identified
in Section 8.1 under which a Member, Manager, officer or Affiliate thereof would
be liable to the Company. No Member, Manager, officer or Affiliate thereof shall
have any personal liability with respect to the satisfaction of any required
indemnification of an indemnitee. Any indemnification required hereunder shall
be made promptly as the liability, loss or expense is incurred or suffered, and
the indemnification provided by this Section 8.5 shall be in addition to any
other rights to which those indemnified may be entitled under any agreement, as
a matter of law or equity, or otherwise, and shall continue as to a Member,
Manager, officer or employee who has ceased to serve in that capacity, and shall
inure to the benefit of the heirs, successors, assigns and administrators of the
indemnitees.

                                      -30-
<PAGE>

                                   ARTICLE 9

                REPRESENTATIONS, WARRANTIES AND CERTAIN COVENANTS

9.1 REPRESENTATIONS AND WARRANTIES

         Each Member hereby represents and warrants to the other Member and to
the Company as of the date hereof the following:

         9.1.1 ORGANIZATION AND EXISTENCE

         Such Member is a corporation duly organized, validly existing and in
good standing under the laws of the jurisdiction in which it was incorporated.
Such Member is duly licensed or qualified to do business and in good standing in
each of the jurisdictions in which the failure to be so licensed or qualified
would have a material adverse effect on its financial condition, operations or
prospects or its ability to perform its obligations hereunder.

         9.1.2 POWER AND AUTHORITY

         Such Member has the full power and authority to execute, deliver and
perform this Agreement, and to own and lease its properties and assets and to
carry on its business as now conducted and as contemplated hereby.

         9.1.3 AUTHORIZATION AND ENFORCEABILITY

         The execution and delivery of this Agreement by such Member and the
carrying out by such Member of the transactions contemplated hereby have been
duly authorized by all requisite corporate actions, and this Agreement has been
duly executed and delivered by such Member and constitutes the legal, valid and
binding obligation of such Member, enforceable against it in accordance with the
terms hereof, subject, as to enforceability of remedies, to limitations imposed
by bankruptcy, insolvency, reorganization, moratorium or other similar laws
relating to or affecting the enforcement of creditors' rights generally and
general principles of equity.

         9.1.4 NO GOVERNMENTAL CONSENTS

         No authorization, consent or approval of, or notice to or filing with,
any governmental authority is required for the execution, delivery and
performance by such Member of this Agreement.

         9.1.5 NO CONFLICT OR BREACH

         None of the execution, delivery and performance by such Member of this
Agreement, the compliance with the terms and provisions hereof, and the carrying
out of the transactions contemplated hereby conflicts or will conflict with or
will result in a breach or violation of any of the terms, conditions or
provisions of any law, governmental rule or regulation or the charter documents,
as amended, or bylaws, as amended, of such Member or any order, writ,
injunction, judgment or decree of any court or governmental authority against
such Member or by which it or any of its proprieties is bound, or any loan

                                      -31-
<PAGE>

agreement, indenture, mortgage, note, resolution, bond, or contract or other
agreement or instrument to which such Member is a party or by which it or any of
its properties is bound, or constitutes or will constitute a default thereunder
or will result in the imposition of any lien upon any of its properties.

         9.1.6 NO PROCEEDINGS

         There are no suits or proceedings pending (other than those disclosed
on Schedule 9.1.6 attached hereto), or to the knowledge of such Member,
threatened in any court or before any regulatory commission, board or other
governmental administrative agency against or affecting such Member that could
have a material adverse effect on the business or operations of such Member,
financial or otherwise, or on its ability to fulfill its obligations hereunder.

         9.1.7 NO COMPETITION

         No Member shall take any action to develop, research, exploit or sell
the Technology other than through the Company or as contemplated herein.

9.2 ADDITIONAL REPRESENTATIONS AND WARRANTIES OF Techniclone

         Techniclone hereby represents and warrants to OXiGENE as of the date
hereof, that (a) it owns all right, title and interest in and to, or controls
with the power unconditionally to license or assign without the further consent
of any other Person and subject to the consent of the University of Texas, all
of the Techniclone Contributed Technology, (b) except for the Pending Matters,
the Techniclone Contributed Technology is free and clear of any liens, claims or
encumbrances, (c) to its knowledge, there is no material and unauthorized use,
infringement or misappropriation of any of its rights in the Techniclone
Contributed Technology, (d) to its knowledge, use of the Techniclone Contributed
Technology will not infringe upon the rights of any third party, (e) Exhibit A
contains a complete and accurate list of all the licenses that are owned or
controlled by Techniclone and that are related to the Field, (f) the Field as
described herein is the entire Field known to Techniclone that is necessary for
the Company to effectuate its intended purposes relative to the Plan, (g) the
scope of the Field, insofar as it relates to the Company's intended purposes
relative to the Plan, is not adversely affected by the exclusion therefrom of
existing or contemplated licenses pursuant to the Pending Matters, (h) all of
the Pending Matters are accurately identified in Exhibit F and true and complete
copies of all the licensing arrangements in place or in negotiation with respect
thereto have been delivered to OXiGENE, (i) Exhibit G is a true and complete
copy of the Texas/Thorpe Agreement, such agreement is a valid and binding
obligation of each party thereto, enforceable in accordance with its terms and
Techniclone is not, and to the best of Techniclone's knowledge each of the other
parties to the Texas/Thorpe Agreement is not, in breach or violation of or
default under such agreement, and (j) to the best of Techniclone's knowledge,
the OXiGENE Contributed Technology and the Techniclone Contributed Technology,
when combined and subjected to the Company's operations contemplated under the
Plan, will be adequate to permit the Company to achieve its stated purposes
relative to the Plan and is all the Technology known to Techniclone that is
owned or controlled by it and OXiGENE that is or may be used or useful with
respect to the development of the Technology.

                                      -32-
<PAGE>

9.3 ADDITIONAL REPRESENTATIONS AND WARRANTIES OF OXiGENE

         OXiGENE hereby represents and warrants to Techniclone as of the date
hereof, that (a) it owns or controls (with the power to license the requisite
interest therein without the necessity of obtaining the prior consent thereto of
any other party), all of the OXiGENE Contributed Technology (except technology
that is not the subject of patents), (b) the OXiGENE Contributed Technology is
free and clear of any liens, claims or encumbrances, (c) to its knowledge, there
is no material and unauthorized use, infringement or misappropriation of any of
its rights in the Oxigene Contributed Technology, (d) to the best of its
knowledge, use of the OXiGENE Contributed Technology within the Licensed Field
(as defined in the OXiGENE License Agreement) will not infringe upon the rights
of any third party, (e) to the best of OXiGENE's knowledge, the OXiGENE
Contributed Technology and the Techniclone Contributed Technology, when combined
and subjected to the Company's operations contemplated under the Plan, will be
adequate to permit the Company to achieve its stated purposes relative to the
Plan and (f) it has the financial ability to fund in full its capital
contribution as set forth in section 3.2(a).

9.4 WARRANTY OF STATEMENTS

         No representation or warranty of either Member, or any exhibit,
document, statement, certificate or schedule pursuant hereto or in connection
with the transactions contemplated hereby, contains or will contain any untrue
statement of a material fact, or omits or will omit to state a material fact
necessary to make statements or facts contained therein not misleading. The
representations and warranties of the Members set forth in this Agreement and in
any exhibit, document, statement, certificate or schedule furnished or to be
furnished pursuant hereto shall be true on and as of the Closing Date as though
such representations and warranties were made on and as of Closing Date.

9.5 COVENANTS

         Each Member hereby agrees that:

         9.5.1 Techniclone shall file a registration statement under the
Securities Act, covering the offer and sale of the Initial Techniclone Shares as
promptly as practicable after the Closing Date, shall use its best efforts to
have such registration statement declared effective by the U.S. Securities and
Exchange Commission as promptly as practicable thereafter and shall cause the
final prospectus included in such registration statement to remain current for
180 days after its effectiveness. If the registration is in connection with an
underwritten offering, OXiGENE agrees to become a party to, and abide by the
terms of, any underwriting agreement that contains terms and provisions
customary under the circumstances.

         9.5.2 Techniclone shall file a registration statement under the
Securities Act covering the offer and sale of the Additional Techniclone Shares
as promptly as practicable after the date on which the first IND that is
described in Section 3.2(b) hereof is filed, shall use its best efforts to have
such registration statement declared effective by the U.S. Securities and
Exchange Commission as promptly as practicable thereafter and shall cause the
final prospectus included in such registration statement to remain current for
180 days. If the registration is in connection with an underwritten offering,
OXiGENE agrees to become a party to and abide by the forms of, any underwriting
agreement.

                                      -33-
<PAGE>

         9.5.3 Each registration statement filed by Techniclone hereunder
shall be prepared carefully by it and shall, when it is filed and when it
becomes effective, comply as to form with all the requirements of the Securities
Act and will not include any untrue statement of a material fact or fail to make
any statement necessary so that the statements made in the registration
statement are not misleading in any material respect; provided, however, that
Techniclone shall have no responsibility with respect to any information
included in a registration statement that is provided by OXiGENE in writing to
Techniclone specifically for inclusion in such registration statement.

         9.5.4 OXiGENE shall timely provide to Techniclone all such
information concerning OXiGENE and its plan of distribution for the securities
included in any registration statement filed by Techniclone hereunder as
Techniclone shall reasonably request, and shall cooperate in all reasonable
respects with Techniclone in connection with the matters contemplated by this
Section 9.5.

         9.5.5 OXiGENE and Techniclone shall exchange mutual, customary
indemnification agreements in connection with each registration statement filed
by Techniclone pursuant to this Section 9.5.

9.6 SURVIVAL OF REPRESENTATIONS, WARRANTIES AND CERTAIN COVENANTS

         The respective representations and warranties of the Members shall
survive the Closing Date and continue in full force and effect for a period
thereafter equal to five (5) years following the Closing Date. The Covenants set
forth in this Section 9 shall survive the Closing Date without limitation.

                                   ARTICLE 10

                         CONDITIONS PRECEDENT TO CLOSING

10.1 CONDITIONS PRECEDENT TO THE OBLIGATIONS OF THE MEMBERS

         All the obligations of any Member under this Agreement are subject to
the fulfillment, at or prior to the Closing Date, of each of the following
conditions:

         10.1.1 NO MISREPRESENTATIONS

         Neither Member shall have discovered, learned or been made aware of any
material error, misstatement or omission in the representations and warranties
made by the other party in Article 9.

                                      -34-
<PAGE>

         10.1.2 COMPLIANCE WITH AGREEMENT

         Each Member shall have performed and complied with all terms, covenants
and conditions required by this Agreement prior to the Closing Date.

         10.1.3 NO LITIGATION

         No suit, action or proceeding against any Member shall be pending or
threatened before any court or governmental agency in which such suit, action or
proceeding seeks to restrain or prohibit or to obtain damages or other relief in
connection with this Agreement or the transactions contemplated hereby.

         10.1.4 ADDITIONAL DOCUMENTS

         Each Member shall have delivered to the other Member such other
instruments and documents as may be, in the opinion of counsel for the other
Member, reasonably necessary to effectuate the transactions contemplated by this
Agreement, and all legal matters in connection with this Agreement and the
transactions contemplated hereby shall have been approved by counsel for the
other Member.

         10.1.5 GOVERNMENTAL APPROVAL AND CONSENTS

         All necessary notifications and filings, if any, required to be made in
or with respect to any relevant country will have been made and all necessary
governmental approvals, if any, shall have been received and the prescribed
waiting periods will have expired or been terminated. No governmental entity
shall have indicated its objection to, or its intent to challenge as violative
of any federal, state or foreign laws, any of the transactions contemplated by
this Agreement or any related documents. In the event a governmental entity
places a condition on its approval of the transaction as contemplated by this
Agreement or any related documents that has a material effect on the proposed
business of the Company, the Members shall attempt to negotiate a mutually
agreeable modification to this Agreement.

         10.1.6 AGREEMENTS

         The Members and the Company have entered into, and duly executed, the
Plan. The Company and Techniclone have entered into, and duly executed, the VTA
Assignment Agreement. The Company and OXiGENE have entered into, and duly
executed, the OXiGENE License Agreement.

10.2 DELIVERY TO OXiGENE

         Techniclone shall have delivered to OXiGENE each of the following at or
prior to the Closing Date:

                                      -35-
<PAGE>

         10.2.1 Confirmation in form and substance reasonably satisfactory to
OXiGENE evidencing receipt of the Techniclone Contributed Technology specified
in Section 3.1;

         10.2.2 Duly executed certificate from an officer of Techniclone that
the representations and warranties of Techniclone contained in Article 9 are
true and correct as of the Closing Date.

10.3 DELIVERY TO Techniclone

         OXiGENE shall have delivered to Techniclone each of the following at or
prior to the Closing Date:

         10.3.1 Confirmation in form and substance reasonably satisfactory to
Techniclone evidencing receipt of its OXiGENE's Contribution specified in
Section 3.1; and

         10.3.2 Duly executed certificate from an officer of OXiGENE that the
representations and warranties of OXiGENE contained in Article 9 are true and
correct as of the Closing Date.

10.4 CLOSING

         The closing hereunder shall occur on the Closing Date at such time and
place as may be mutually agreed upon by the parties. At the closing, each party
shall deliver such documents, instruments and materials as are called for by
this Agreement or as may be reasonably required in order to carry out the
provisions and purposes hereof, all of which shall be satisfactory in substance
and form to legal counsel for each party.

                                   ARTICLE 11

                                 INDEMNIFICATION
11.1     INDEMNIFICATION

         11.1.1 Techniclone shall indemnify and hold OXiGENE, the Company and
their respective Managers, officers, employees and agents harmless from and
against any and all claims, liabilities, losses, costs, damages and expenses,
including costs of investigation, court costs and reasonable attorneys' fees, to
which any of them may become subject arising from or in any manner connected
with, directly or indirectly, any material misstatement, error or omission in
any representation or warranty of Techniclone contained in this Agreement
(without effect on Techniclone's liability under the various instruments and
documents to be executed in connection herewith).

         11.1.2 OXiGENE shall indemnify Techniclone, the Company and their
respective Managers, officers, employees and agents to the same extent that
OXiGENE is being indemnified pursuant to Section 11.1(a) above.

                                      -36-
<PAGE>

11.2 MECHANISM FOR INDEMNIFICATION

         The Member seeking indemnification hereunder ("Indemnified Member")
shall give written notice to the indemnifying Member ("Indemnifying Member") of
its indemnification claims hereunder, specifying the amount and nature of the
claim, and giving the Indemnifying Member the right to contest any such claim
represented by counsel of its choice; if any such claim is made hereunder by the
Indemnified Member and such claim arises from the claims of a third party
against the Indemnified Member and the Indemnifying Member does not elect to
undertake the defense thereof by written notice within fifteen (15) days after
receipt of the original notice from the Indemnified Member, the Indemnified
Member shall be entitled to indemnity pursuant to the terms of this Agreement to
the extent of its payment in respect of such claim. To the extent that the
Indemnifying Member undertakes the defense of such claim in good faith by
proceeding diligently at its expense, and without materially impairing the
financial conditions or operations of the Indemnified Member, the Indemnified
Member shall be entitled to indemnity hereunder only if, and to the extent that,
such defense is unsuccessful as determined by a final judgment of a court of
competent jurisdiction or is settled with the consent of the Indemnifying
Member. The Member defending a third-party claim shall have the right to choose
its own counsel.

                                   ARTICLE 12

                               DISPUTE RESOLUTION

12.1 DISPUTE

         Subject to Section 6.2.3, in the event of any controversy or claim
arising out of or relating to this Agreement, or the breach thereof, or if there
is a deadlock among the Managers with respect to any management decision (a
"Dispute"), then upon the written request of either Member that includes a
summary of the Dispute, the Company shall submit the Dispute to Mediation
pursuant to Section 12.2.

12.2 MEDIATION

         Any Dispute that the Members are unable to resolve shall be submitted
by any Member to nonbinding mediation administered by the American Arbitration
Association (the "AAA") under its Commercial Mediation Rules. The mediation will
be held in Boston, Massachusetts, if initiated by Techniclone and in Orange
County, California, if initiated by OXiGENE. The Members will mutually determine
the mediator from a list of mediators obtained from the American Arbitration
Association office located in the city in which the proceeding will take place.
If the Members are unable to agree on the mediator, the mediator will be
selected by the American Arbitration Association with a preference for selecting
a retired federal district judge or state superior court judge as the mediator.
Any mediation initiated under this Section will be concluded within 30 days of
the filing by a Member of a written request to the AAA for mediation. Each
Member will pay its own costs plus an equal share of the cost of the mediator
and the mediation facilities.

12.3 ARBITRATION

         If a Dispute is not resolved through Mediation under Section 12.2 above
or if both Members waive Mediation, such Dispute shall be submitted by any
Member to binding arbitration administered by the AAA under its Commercial
Arbitration Rules, including the AAA's Optional Procedures for Large, Complex

                                      -37-
<PAGE>

Commercial Disputes, to the extent not modified by this Section 12.3, before a
single arbitrator. The Members will mutually determine the arbitrator from a
list of arbitrators obtained from the American Arbitration Association office
located in the city in which the Mediation took place. If the Members are unable
to agree on the arbitrator, the arbitrator will be selected by the American
Arbitration Association with a preference for selecting a retired federal
district judge or state superior court judge as the arbitrator.

         12.3.1 PLACE OF ARBITRATION

         The arbitration will be held in Boston, Massachusetts, if initiated by
Techniclone and in Orange County, California, if initiated by OXiGENE.

         12.3.2 GOVERNING LAW

         This Agreement shall be governed by and interpreted in accordance with
the laws of the State of Delaware without giving effect to any conflict of law
rules. The Members acknowledge that this Agreement evidences a transaction
involving interstate commerce. The United States Arbitration Act shall govern
the interpretation, enforcement and proceedings pursuant to the Arbitration
under Section 12.3 of this Agreement.

         12.3.3 PROVISIONAL REMEDIES

         Prior to the selection of the arbitrator required under Section 12.3 of
this Agreement, any Member may seek a provisional remedy necessary to prevent
irreparable harm (including, without limitation, injunction, attachment or other
similar remedy) or may seek to enforce the provisions of Section 2.7 by
initiating a demand for arbitration in accordance with the provisions of Section
12.3 (whether or not the mediation pursuant to Section 12.2 has been completed)
and by proceeding pursuant to the AAA's Optional Rules for Emergency Measures of
Protection. Once an arbitrator has been selected in accordance with Section
12.3, a party seeking a provisional remedy shall proceed in accordance with
Article 21 of the AAA's International Arbitration Rules.

         12.3.4 ENFORCEMENT OF AWARD

         The Members agree that judgment on any award rendered by the
arbitrators may be entered in any court having jurisdiction thereof including,
but not limited to, the state courts of California and Massachusetts and the
U.S. federal courts located therein to which the Members hereby consent to
submit to jurisdiction for purposes of enforcement of any arbitration award.

                                      -38-
<PAGE>

                                   ARTICLE 13

                        TRANSFERS OF MEMBERSHIP INTERESTS

13.1 OVERALL RESTRICTIONS

         The Company will be owned on the Closing Date by two (2) entities that
have the technical compatibility and financial stability that are major elements
contributing toward the prospect of the future success of the Company. Each
Member is entering into and performing its obligations under this Agreement in
reliance upon the unique and particular know-how, personnel, assets and services
being contributed and performed by the other Member. Except in accordance with
the terms of this Agreement, no Member shall Transfer all or any part of its
Membership Interest, or any interest therein, unless the Member (a) obtains the
prior written consent of the other Member ("Nontransferring Member"), which
consent may not be unreasonably withheld, and (b) provides satisfactory evidence
to the Company that such Transfer shall not violate applicable securities laws.
Unless such prior requirements are met, the proposed Transfer may not take
place, and any attempted Transfer in derogation hereof shall be deemed null and
void. Notwithstanding the foregoing, a Member may transfer all or part of its
Membership Interest within or among the members of its "affiliated group" within
the meaning of Section 1504(a)(1) of the Code. If for any reason any clause or
provision of this Section 13.1 should be held unenforceable, invalid or in
violation of law by any court or tribunal, then the Non-transferring Member
shall have the right, exercisable in writing within ninety (90) days of the date
of final determination of invalidity or unenforceability, to purchase the
Membership Interest Members such transferring Member purported to Transfer,
pursuant to the terms of Section 13.3.

13.2 ADDITIONAL RESTRICTIONS

         Upon the occurrence of any of the following events with respect to a
Member ("Occurrence Member") (wherein there is not a continuity of proprietary
interest of the shareholders of the Member who owned the shares of the Member
prior to the occurrence of such event): (a) any transfer of substantially all of
its assets, (b) a liquidation or dissolution, or (c) any insolvency or
bankruptcy proceeding, the Member that is not involved with such an occurrence
shall have the right, exercisable in writing within sixty (60) days after the
later of (i) receipt of written notice of such occurrence and (ii) the
conclusion of the appraisal contemplated in Section 13.3, to purchase the
Occurrence Member's entire Membership Interest pursuant to the terms of Section
13.3 or to dissolve the Company pursuant to the terms of Article 14. The
Occurrence Member shall notify the other Member in writing of any occurrence
described in clauses (a), (b) or (c) of this Section 13.2 at the earliest time
practicable.

13.3 PURCHASE PRICE AND PAYMENT DATE

         For purposes of Sections 13.1 and 13.2, the purchase price to be paid
for the Membership Interest of the transferring Member or Occurrence Member
shall be computed as follows:

                                      -39-
<PAGE>

         13.3.1 Within sixty (60) days after the occurrence of an event
described in Section 13.2, the Members shall jointly appoint an investment
banking firm or failing this joint action, each shall designate an investment
banking firm. Within thirty (30) days after their appointment, the designated
investment banking firms shall designate an additional investment banking firm
(the "Neutral Investment Banker") (collectively, the Neutral Investment Banker
and the two investment banking firms designated by the Members being referred to
as the "Three Investment Bankers"). The failure by any Member to appoint an
investment banking firm within the time allowed shall be deemed equivalent to
appointing the other Member's investment banking firm as the jointly appointed
investment banking firm. Within sixty (60) days after the appointment of the
jointly appointed investment banking firm or the Neutral Investment Banker, as
the case may be, the jointly appointed investment banking firm or the Three
Investment Bankers, by a majority vote, shall render their appraisal of the fair
market value of the Membership Interest being purchased, which appraisal shall
be binding and conclusive. The Company shall bear all appraisal expenses.

         13.3.2 The payment date of the purchase price pursuant to this Section
13.3 shall not be later than sixty (60) days after the sixty (60) day period set
forth in Section 13.3(a).

13.4 CHANGE OF CONTROL

         13.4.1 In the event of a Change in Control (as defined below) of either
Member (the "Acquired Member"), the other Member shall have the option to
purchase the Membership Interest of the Acquired Member in accordance with the
procedure set forth in Section 13.3.

         13.4.2 For purposes of this Section 13.4, a "Change in Control" occurs
when (a) any Person becomes, after the date hereof, the beneficial owner,
directly or indirectly, of more than 50% of the outstanding securities of the
Acquired Member having a right to vote in the election of Directors or (b) the
Acquired Member is involved in a reorganization, merger or consolidation, except
a "Change in Control" will not have occurred if, after the transaction, 50% or
more of the outstanding voting securities of the corporation acquiring the
Acquired Member's voting securities or resulting or surviving from the
reorganization, merger or consolidation are owned by the Acquired Member's
shareholders in the same proportion as they own the Acquired Member's voting
securities immediately prior to such transaction.

13.5 ADMISSION OF SUBSTITUTED MEMBERS

         Subject to the other provisions of this Section 13, a transferee of an
Interest may be admitted to the Company as a substituted Member only upon
satisfaction of the following conditions:

         13.5.1 The Members unanimously consent to such admission, which consent
may be given or withheld in the sole discretion of each Member;

         13.5.2 The transferee becomes a party to this Agreement as a Member and
executes such documents and instruments as the Board may reasonably request as
may be necessary or appropriate to confirm such transferee as a Member and bind
such transferee by the terms and conditions of this Agreement; and

                                      -40-
<PAGE>

         13.5.3 The transferee pays or reimburses the Company for all reasonable
legal, filing and publication costs that the Company incurs in connection with
the admission of the transferee as a Member with respect to the transferred
Interest.

13.6 SPECIFIC PERFORMANCE

         Each of the Members acknowledges that the rights and obligations
provided by this Section 13 are of unique value to it and that the payment of
monetary damages could not adequately compensate the other Member for any breach
of the obligations set forth herein. Accordingly, the rights of the Members set
forth in this Section 13 shall be specifically enforceable in accordance with
their terms.

                                   ARTICLE 14

                        SALE, DISSOLUTION AND LIQUIDATION

14.1 EVENTS OF DISSOLUTION

         14.1.1 The Company shall be dissolved upon the mutual written consent
of the Members.

         14.1.2 The Company shall be dissolved upon the occurrence of any of the
events set forth in Section 13.2 if the Member that is not the Occurrence Member
shall not have exercised the purchase option provided in Section 13.2 and shall
have requested, within sixty (60) days after such occurrence, that the Company
be dissolved.

         14.1.3 The Company may be dissolved for federal and Delaware income tax
purposes, but preserved in nominal form for Delaware state law purposes, by
either Member upon the bankruptcy, receivership or insolvency of the other
Member or the Company, or upon the material breach of this Agreement by the
other Member.

         14.1.4 The Members recognize that the Company may be dissolved by order
of a court of competent jurisdiction pursuant to ss.18-802 of the Act.

         14.1.5 Either Member may cause the Company to be dissolved if the
material requirements of Section 7.2.1(b) are not satisfied.

         14.1.6 The Company shall be dissolved upon the abandonment of the Plan,
unless both Members agree to continue the existence of the Company.

14.2 FINAL ACCOUNTING AND TAX RETURNS

         Upon the dissolution of the Company, a complete and accurate accounting
shall be made by the Company's independent certified public accountants from the
date of the last previous accounting to the date of dissolution, and all
required tax returns shall be timely filed in connection therewith.

                                      -41-
<PAGE>

14.3 LIQUIDATION

         Upon the dissolution of the Company, each Member shall appoint an
individual to act as a liquidator to wind up the Company (and, if either Member
fails to appoint such individual within sixty (60) days after the written
request of the other Member, the individual that shall have been appointed by
such other Member within such sixty (60) day period shall act as the liquidator)
(the individuals so appointed shall be referred to collectively as the
"Liquidator"). The Liquidator shall have full power and authority to take full
account of the Company's assets and liabilities and to wind up and liquidate the
affairs of the Company in an orderly and business-like manner as is consistent
with obtaining the fair value thereof upon dissolution. The Company shall engage
in no further business thereafter other than as necessary to operate on an
interim basis, collect its receivables, pay its liabilities and liquidate its
assets.

14.4 DISTRIBUTIONS IN LIQUIDATION

         14.4.1 Upon dissolution of the Company and the liquidation of the
assets of the Company pursuant to this Article 14, the Liquidator shall wind up
the affairs of the Company and liquidate the assets as promptly as is consistent
with obtaining fair value therefor and cause the remaining assets of the
Company, including proceeds of sales or other dispositions in liquidation of
assets, to be applied in accordance with the following priorities:

         14.4.2 First, to payment of the debts and obligations of the Company to
its creditors (other than a Member), including sales commissions and other
expenses incident to any sale of the assets of the Company;

         14.4.3 Second, to the establishment of such reserves as the Liquidator
may deem reasonably necessary for any unliquidated contingent or unforeseen
liabilities or obligations of the Company;

         14.4.4 Third, to the payment in full of loans (including for this
purpose, accrued interest thereon through the date of payment) to the Company by
the Members, pro rata, according to the relative amount of such unpaid loans
(including for this purpose, accrued interest thereon through the date of
payment) and then to the payment in full of any other debts and obligations of
the Company to its Members (e.g., under service agreements), pro rata, according
to the relative amount of such debts and obligations;

         14.4.5 Fourth, to the Members having positive Capital Accounts pro rata
in accordance with their relative positive Capital Accounts (as determined after
taking into account all Capital Account adjustments for the Company's Fiscal
Year during which such liquidation occurs), until all such positive Capital
Accounts are reduced to zero;

         14.4.6 Fifth, among the Members in proportion to their respective
Membership Interests; and,

         14.4.7 Notwithstanding the foregoing provisions of this Section 14.4,
upon liquidation of the Company, Company Discoveries shall be the joint property
of each Member. Each Member shall have joint and non-exclusive rights to develop
or sublicense the Company Discoveries; provided, however, that Techniclone shall
have exclusive ownership, development and sublicense rights in the Company

                                      -42-
<PAGE>

Discoveries until Techniclone has received cumulative distributions equal to the
Early Termination Preference; and provided further that the OXiGENE Contributed
Technology shall be distributed in kind to OXiGENE and the Techniclone
Contributed Technology shall be distributed in kind to Techniclone, each at the
value set forth in Section 3.1.

         The reserves established pursuant to clause (ii) of this Section
14.4(a) shall be paid over by the Liquidator to a bank or other financial
institution to be held in escrow for the purpose of paying unliquidated,
contingent or unforeseen liabilities or obligations, and, at the expiration of
such period as the Liquidator deems advisable, such reserves shall be
distributed to the Members or their assigns in the priority set forth in clauses
(iii) and (iv) of this Section 14.4(a). Distributions to the Members pursuant to
this Section 14.4(a) shall be made within the time period prescribed by
Regulations Section 1.704-1 (b)(2)(ii)(b).

         14.4.8 In the event the Liquidator determines that an immediate sale of
part or all of the Company assets would cause undue loss to the Members, the
Liquidator, in order to avoid such loss, may either (i) defer liquidation of any
assets of the Company for a reasonable time, except those assets necessary to
satisfy Company debts and obligations, or (ii) distribute the assets in kind to
the Members. If any assets of the Company are to be distributed in kind, such
assets shall be valued and shall be deemed sold at their fair market value and
any gain or loss deemed realized shall be allocated to the Capital Accounts of
the Members for purposes of applying this Section 14.4 as if such gain or loss
had actually been fully realized. Any assets that are to be so distributed shall
be distributed on the basis of the fair market value thereof and any Member
entitled to an interest in such assets shall receive such interest therein as a
tenant-in-common with all other Members so entitled. The fair market value of
such assets shall be determined by an appraiser to be selected by the Liquidator
or by agreement of all the Members. In the event of such distribution in kind,
the distributee Member shall not thereafter sell or otherwise Transfer or
dispose of any interest in any assets so distributed which it holds as a
tenant-in-common without first offering such interest in writing to the other
tenant-in-common upon the same terms and conditions and for the same price as
such proposed sale or Transfer. The other tenant-in-common shall have thirty
(30) days after the receipt of such offer within which to accept the same and
shall have the right to acquire such interest. If the other tenant-in-common
shall fail to accept such offer within such period of time, such distributee
Member shall be free to sell the interest in such assets upon the terms and
conditions described in the offer disclosed to the other tenants-in-common free
of any further rights of first refusal.

         14.4.9 During the period, if any, that Techniclone has exclusive
ownership, development and sublicense rights to develop or sublicense the
Company Discoveries pursuant to the first proviso of the second sentence of
subsection 14.4(a)(vi), Techniclone will (i) promptly pay to OXiGENE, no less
often than annually, the Early Termination Remainder, and (ii) provide OXiGENE
with quarterly unaudited financial statements and annual audited financial
statements.

14.5 DEFICIT CAPITAL ACCOUNTS

         Except as may otherwise be required by law, notwithstanding anything to
the contrary contained in this Agreement, to the extent that any Member has a
Deficit Capital Account balance upon dissolution of the Company, that balance
shall not be an asset of the Company and that Member shall not be obligated to
contribute any amount to the Company to bring the balance of that Member's
Capital Account to zero.

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14.6 TERMINATION OF COMPANY AND AGREEMENT

         Upon the completion of the distributions in liquidation of the Company
as provided in this Article 14, (a) the Liquidator shall take all actions as may
be appropriate to finally dissolve and liquidate the Company and (b) this
Agreement shall terminate.

                                   ARTICLE 15

                             ACCOUNTING AND REPORTS

15.1 BOOKS AND RECORDS

         15.1.1 Procedures. The Board shall implement standard procedures with
respect to accounting, financial reporting and management information,
including, without limitation, statements reflecting Company distributions,
earnings, Profits and Losses, residual value of Company Property and taxable
income.

         15.1.2 Records. At all times during the term of the Company, the Board
shall keep or cause to be kept full and accurate books, records and accounts,
which shall, in reasonable detail, accurately and fairly reflect each
transaction of the Company. Each Member and its representatives shall have
access to such books, records and documents during reasonable business hours and
may inspect and make copies of any of them. The Board may delegate to a third
party or Member the duty to maintain and oversee the preparation of such records
and books of account. The Board shall maintain all such books and records for
the six (6) most recent Fiscal Years or until such year is closed for tax audit
purposes.

         15.1.3 Audit of Company's Statements. The Company will engage and pay
for an external accounting firm to audit its financial statements at least
annually, which firm may, but need not be, the external accounting firm for one
or both of the Members. Since it is anticipated that one Member, as chosen by
the Board (the "Accounting Services Provider"), will provide accounting services
to the Company, the Board is advised that, whenever practicable, it should
appoint the primary external accounting firm which provides services to the
Accounting Services Provider. The Member which is not the Accounting Services
Provider shall have the right, during regular business hours and upon reasonable
advance notice, to review the audited financial statements and the related work
papers and findings of the external accounting firm supporting the financial
statements or request another external accounting firm to perform such
examination, the cost of which shall be borne by the party requesting the
examination.

         15.1.4 Examination of Member Transactions. Each Member shall keep
comprehensive books and records relating to (i) such Member's reimbursements
under this Agreement and (ii) any compensation or reimbursements under any
agreement with the Company, on a full accrual basis of accounting in accordance
with generally accepted accounting principles for the three (3) most recent
Fiscal Years. Either Member, upon reasonable advance notice to the other Member,
may examine or engage an external accounting firm to examine the accuracy of
revenues, billings and supporting documentation of the other Member for services
or payments to or from the Company during the prior three (3) Fiscal Years,
including under the Sponsored Research Agreement, the OXiGENE License Agreement

                                      -44-
<PAGE>

and any other agreements involving the Company and the other Member. The Member
requesting the review shall, for purposes of such review, utilize the other
Member's regular outside certified public accounting firm. The cost of such
examination shall be borne by the Member requesting the examination; however, in
the event such examination reveals information that deviates by 5% or more from
the information previously provided to the Member requesting the examination,
the cost of the examination shall be borne by the other Member.

15.2 ACCOUNTING METHOD

         The books and records of the Company shall be kept in accordance with
GAAP applied on a consistent basis from year to year.

15.3 FISCAL YEAR

         Unless otherwise determined by unanimous vote of the Board, the Company
shall use the calendar year as its fiscal year for all financial reporting and
tax purposes (the "Fiscal Year").

15.4 REPORTS; TAX RETURNS

         (a) Copies of all accounts, reports and other writings pertaining to
the business of the Company furnished by a Member, the Company or the Company's
accountants to any Member or regulatory agency shall contemporaneously be
delivered to all Members.

         (b) Prior to March 15 of each year, the Board shall provide to the
Members regular annual audited financial statements prepared by independent,
nationally recognized certified public accountants as chosen under Section
15.l(c), which shall include a statement of profits and losses, changes in
financial position and a balance sheet for the year then ended, as well as such
other appropriate financial information reasonably requested by the Board or
Members.

         (c) The Board shall cause to be prepared and filed, on the Company's
behalf and at the Company's expense, all federal, state and other tax returns
required to be filed, and shall submit the same to the Members for review and
approval not less than thirty (30) days prior to the respective due dates for
such returns (including any extensions thereof), but, with respect to the
Company's United States federal income tax information return, in no event later
than May 15 of each year. Apportionment data for state returns will be provided
by June 1 of each year.

         (d) Within thirty (30) days of the end of each calendar month (or
sooner if available) the Company shall provide unaudited financial statements
prepared in accordance with GAAP to each Member .

         (e) Within thirty (30) days after the end of each calendar quarter, the
Company shall provide unaudited quarterly financial statements showing the
quarterly and annual financial results of the Company and comparing such
financial results to the projections of income and expenses in the Approved
Budget.

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<PAGE>

15.5 REQUIRED GOVERNMENTAL FILINGS

         The Board shall cause the Company to file, on or before the dates the
same may be due, giving effect to extensions obtained, all reports, returns and
applications that may be required by any governmental or quasi-governmental body
having jurisdiction.

                                   ARTICLE 16

                               GENERAL PROVISIONS

16.1 NOTICES

         Any notice, request, instruction or other document to be given
hereunder by a Member to another Member hereto shall be in writing, delivered in
person, or mailed by certified or registered mail, return receipt requested, or
transmitted by facsimile transmission with electronic confirmation of receipt to
the addressee's address or facsimile number set forth below (or such other
address or facsimile number as the party changing its address specifies in a
notice to the other parties):

                  If to Techniclone:

                           Techniclone Corporation
                           14282 Franklin Ave.
                           Tustin, CA 92780
                           Phone: (714) 508-6000
                           Facsimile: (714) 838-9433

                  with a copy to:

                           Jeffers, Shaff & Falk, LLP
                           18881 Von Karman Ave., Suite 1400
                           Irvine, CA 92612
                           Attention:  Mark R. Ziebell
                           Phone: (949) 660-7700
                           Facsimile: (949) 660-7799

                  If to OXiGENE:

                           OXiGENE INC
                           One Copley Place, Suite 602
                           Boston, MA 02116
                           Phone: (617) 536-9500
                           Facsimile: (617) 536-4700

                                      -46-
<PAGE>

                  with a copy to:

                           Cadwalader, Wickersham & Taft
                           100 Maiden Lane
                           New York, NY 10038
                           Phone: (212)504-6000
                           Facsimile: (212)504-6666
                           Attention: Gerald Eppner

         Notices shall be deemed to have been given on the date of service, if
served personally on the party to whom notice is to be given, or on the first
day after transmission by facsimile transmission, if transmitted by facsimile as
set forth above, or on the fifth day after mailing, if mailed as set forth
above.

16.2 WAIVER

         No waiver of any breach of the terms of this Agreement shall be
effective unless such waiver is in writing and signed by the Member against whom
such waiver is claimed. No waiver of any breach shall be deemed to be a waiver
of any other or subsequent breach.

16.3 SEVERABILITY

         If any provision of this Agreement shall be held to be invalid, illegal
or unenforceable, the validity, legality and enforceability of the remaining
provisions shall not in any way be affected or impaired thereby.

16.4 WAIVER OF PARTITION

         No Member, either directly or indirectly, shall take any action to
require partition of the Company or any of its assets or properties.
Notwithstanding any provisions of applicable law to the contrary, each Member
(and its successors and assigns) hereby irrevocably waives any and all right to
maintain any action for partition or to compel any sale with respect to its
Membership Interest, or with respect to any assets or properties of the Company,
except as expressly provided in this Agreement.

16.5 FURTHER ASSURANCES

         Each Member shall execute such deeds, assignments, endorsements,
evidences of transfer and other instruments and documents and shall give further
assurances as shall be necessary to perform its obligations hereunder and shall
execute such estoppel and other documents as are reasonably requested by any
other Member regarding the status of the Company.

16.6 GOVERNING LAW

         This Agreement shall be governed by and construed in accordance with
the laws of the State of Delaware, without regard to the choice of law
provisions of the State of Delaware or any other jurisdiction.

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<PAGE>

16.7 COUNTERPARTS

         This Agreement may be executed in any number of counterparts, each of
which shall be deemed an original, but all of which shall constitute one and the
same instrument.

16.8 LIMITATION ON RIGHTS OF OTHERS

         This Agreement is entered into between the Members for the exclusive
benefit of the Company, its Members, and their successors and permitted assigns.
This Agreement is not intended for the benefit of any creditor of the Company or
any other Person. Except to the extent provided by applicable statute, and then
only to that extent, no creditor or third party shall have any rights under this
Agreement or under any other agreement between the Company and any Member with
respect to any contribution to the Company or otherwise.

16.9 SUCCESSORS AND ASSIGNS

         This Agreement shall be binding on and inure to the benefit of the
Members and their respective successors and permitted assigns.

16.10 ENTIRE AGREEMENT; AMENDMENT

         This Agreement constitutes the entire agreement between the Members
with respect to the subject matter hereof and supersedes all prior agreements
and understandings, whether oral or written, between the Members (and their
Affiliates) with respect to the subject matter hereof, including the
Confidential Disclosure and Preliminary Invention Rights Agreement dated April
1, 2000 countersigned between OXiGENE and Techniclone regarding confidential
information (which is superseded and replaced by Section 2.7). This Agreement
may be amended only in writing signed by all the Members.

16.11 EXPENSES

         Except as otherwise provided herein or agreed to in writing by the
Members or their Affiliates, each Member shall bear its own costs and expenses,
including legal fees, associated with carrying on its business as a Member
hereof.

16.12 CONSTRUCTION

         This Agreement has been submitted to the scrutiny of, and has been
negotiated by, all Members hereto and their counsel, and shall be given a fair
and reasonable interpretation in accordance with the terms hereof, without
consideration or weight being given to its having been drafted by any party
hereto or its counsel.

16.13 DISCLAIMER OF AGENCY

         This Agreement does not create any entity or relationship beyond the
scope set forth herein, and except as otherwise expressly provided herein, this
Agreement shall not constitute any Member the legal representative or agent of
the other, nor shall any Member or any Affiliate of a Member have the right or
authority to assume, create or incur any liability or obligation, express or
implied, against, in the name of or on behalf of any other Member, its
Affiliates, the Company or its Affiliates.

                                      -48-
<PAGE>

16.14 RIGHTS AND REMEDIES

         The rights and remedies provided by this Agreement are cumulative and
the use of any one right or remedy shall not preclude or waive the right to use
any or all other remedies. These rights and remedies are given in addition to
any other rights, other than the right of partition, the Members may have by
law, statute, ordinance or otherwise.

16.15 ATTORNEYS' FEES

         In the event of a dispute between the Manager and Members, or the
Members arising out of this Agreement that is arbitrated or litigated, the
nonprevailing party shall pay the reasonable costs and attorneys' fees of the
prevailing party, including the reasonable costs and attorneys' fees incurred in
the appeal of any final or interlocutory judgment.

                                      -49-
<PAGE>

         IN WITNESS WHEREOF, the Members hereto have executed this Limited
Liability Company Agreement of ARCUS THERAPEUTICS LLC as of the day and year
first above written.


OXiGENE INC.                                        TECHNICLONE CORPORATION



By:   /S/ BJORN NORDENVALL                          By:  /S/JOHN BONFIGLIO
      --------------------                               -----------------
      Bjorn Nordenvall                                   John Bonfiglio
      President and Chief Executive Officer              President


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