AMENDMENT AGREEMENT #1

This AMENDMENT AGREEMENT #1 ("Amendment") is made and dated as of June 14, 2000
(the "Effective Amendment Date") by and between Schering Aktiengesellschaft
("Schering") and Techniclone Corporation ("Techniclone").

WHEREAS, Schering and Techniclone entered into the License Agreement dated as of
March 8, 1999 relating to the grant by Techniclone to Schering of certain rights
in the area of radiolabeled antibodies for use in oncology, and the development
by the Parties of a Product (the "Agreement") ;

WHEREAS, the Agreement calls for Techniclone to bear a portion of certain
Clinical Development Expenses and all of certain CMC/Manufacturing Expenses; and

WHEREAS, Techniclone is desirous of having Schering take over the responsibility
for paying Techniclone's portion of Clinical Development Expenses in two stages
(described below) through Decision Point #2 (defined below), and Schering is
willing to assume such payment responsibilities (but not Techniclone's
obligations to perform and pay for CMC/Manufacturing) in exchange for the
consideration described in this Amendment;

NOW THEREFORE, intending to be legally bound and for good and sufficient
consideration, the receipt and sufficiency of which is hereby acknowledged, the
Parties agree as follows.

SECTION 1: DEFINITIONS. Capitalized terms used in this Amendment shall have the
meanings ascribed in the Agreement. The following additional terms shall be
added to "Article I: Definitions" of the Agreement:

         "DECISION POINT #1" means the date on which the clinical study results
are finalized for the Phase I Maximum Tolerated Dose Trial.

         "DECISION POINT #2" means the date on which the first twenty-eight (28)
fully evaluable patients have completed the protocol for the Phase II/III
Clinical Trial.

         "PAYMENT SHARES" means the common equity shares of Techniclone that
Techniclone transfers to Schering to fulfill Techniclone's payment obligations
pursuant to Section 3.04(d). Such shares shall be registered with the United
States Securities and Exchange Commission, and shall be saleable by Schering in
the public market for securities in the United States through a broker-dealer
licensed by the United States Securities and Exchange Commission, upon an S-3
registration statement filed by Techniclone with the United States Securities
and Exchange Commission relating thereto becoming effective.

<PAGE>

         "PHASE I MAXIMUM TOLERATED DOSE TRIAL" means a clinical trial of
Product in humans to establish the maximum tolerated dose and to collect
dosimetry data.

         "PHASE II/III CLINICAL TRIAL" means a clinical trial of Product in
humans designed to fulfill the FDA requirements of both a Phase II Clinical
Trial and a Phase III Clinical Trial, sufficient to avoid the necessity of
conducting a separate Phase II Clinical Trial and Phase III Clinical Trial,
while providing adequate data to support a grant of Regulatory Approval from
EMEA and FDA.

         "PROCEEDS" means the cash amount that Schering receives as a result of
selling Payment Shares in the public market for securities in the United States,
net of commissions and other expenses of Schering related to the sale of the
Payment Shares .

SECTION 2: AMENDMENT OF SECTION 3.04(b). The Parties agree that Section 3.04 (b)
(ii) of the Agreement shall be deleted in its entirety and replaced with the
following language:

                           (ii)     CLINICAL DEVELOPMENT EXPENSES.

                           (A) CLINICAL DEVELOPMENT EXPENSES FROM EFFECTIVE
                           AMENDMENT DATE THROUGH DECISION POINT #1. Schering
                           shall be responsible for one hundred percent (100%)
                           of all Clinical Development Expenses, subject to a
                           maximum of one million, three hundred thousand United
                           States dollars ($1,300,000), incurred from the
                           Effective Amendment Date through Decision Point #1
                           for Products in the Territory; provided however that
                           Techniclone shall be responsible for one hundred
                           percent (100%) of Clinical Development Expenses
                           relating to the manufacture, packaging and delivery
                           to clinical sites of Oncolym for use in Clinical
                           Development through Decision Point #1. In the event
                           that Clinical Development Expenses incurred from the
                           Effective Amendment Date through Decision Point #1
                           exceed one million three hundred thousand United
                           States dollars ($1,300,000), then Schering shall be
                           responsible for eighty percent (80%) of the excess
                           and Techniclone shall be responsible for twenty
                           percent (20%) of the excess. In the event that
                           Schering determines to continue Clinical Development
                           after Decision Point #1, then clause B below shall be
                           applicable.

                                       2
<PAGE>

                           (B) CLINICAL DEVELOPMENT EXPENSES FROM DECISION POINT
                           #1 THROUGH DECISION POINT #2. In the event that
                           Schering determines to continue Clinical Development
                           following Decision Point #1, then Schering shall be
                           responsible for one hundred percent (100%) of all
                           Clinical Development Expenses, subject to a maximum
                           of one million, seven hundred thousand United States
                           dollars ($1,700,000), incurred from Decision Point #1
                           through Decision Point #2 for Products in the
                           Territory; provided however that Techniclone shall be
                           responsible for one hundred percent (100%) of
                           Clinical Development Expenses relating to the
                           manufacture, packaging and delivery to clinical sites
                           of Oncolym for use in Clinical Development from
                           Decision Point #1 through Decision Point #2. In the
                           event that Clinical Development Expenses incurred
                           from Decision Point #1 through Decision Point #2
                           exceed one million, seven hundred thousand United
                           States dollars ($1,700,000), then Schering shall be
                           responsible for eighty percent (80%) of the excess
                           and Techniclone shall be responsible for twenty
                           percent (20%) of the excess. In the event that
                           Schering determines to continue Clinical Development
                           after Decision Point #2, then Schering shall be
                           responsible for eighty percent (80%) of all Clinical
                           Development Expenses incurred after Decision Point #2
                           (including Clinical Development Expenses relating to
                           the manufacture, packaging and delivery to clinical
                           sites of Oncolym for use in Clinical Development) for
                           Products in the Territory, and Techniclone shall be
                           solely responsible for the remaining twenty percent
                           (20%) of such Clinical Development Expenses.

SECTION 3: ADDITION OF SECTION 3.04(d). The Parties agree to add the following
new Section 3.04(d) to the Agreement, as follows:

                  (d)  PAYMENTS TO SCHERING BY TECHNICLONE.

                           (A) FROM EFFECTIVE AMENDMENT DATE THROUGH DECISION
                           POINT #1.

                                    (i) In consideration of Schering's agreement
                           to undertake responsibility for payment of Clinical
                           Development Expenses as described above from the
                           Effective Amendment Date through Decision Point #1,
                           Techniclone agrees to transfer to Schering, within
                           three (3) days after the registration statement
                           described below in Section 3.04(d)(A)(iii) becomes
                           effective, Payment Shares equal to one million, three
                           hundred thousand United States dollars ($1,300,000)
                           determined by the average closing stock price for the
                           five trading days prior to the date the registration
                           statement becomes effective. In addition, in lieu of
                           transferring all or part of the Payment Shares to
                           Schering, Techniclone shall have the right to pay
                           Schering in cash at any time to satisfy the

                                       3
<PAGE>

                           obligations of Techniclone hereunder, for either the
                           full amount due to Schering or any portion thereof,
                           at the sole discretion of Techniclone. The Parties
                           recognize that the public market for securities in
                           the United States is volatile, and that as a result
                           Schering may not realize Proceeds of one million,
                           three hundred thousand United States dollars
                           ($1,300,000) (or such lower amount as may be
                           applicable if Techniclone has satisfied part of its
                           obligations hereunder in cash) when it sells the
                           Payment Shares. In the event that Schering realizes
                           Proceeds of less than one million, three hundred
                           thousand United States dollars ($1,300,000) (or such
                           lower amount as may be applicable if Techniclone has
                           satisfied part of its obligations hereunder in cash)
                           as a result of the sale of the Payment Shares,
                           Schering shall notify Techniclone of the shortfall.
                           Techniclone shall pay the amount of the shortfall to
                           Schering either by issuing additional Payment Shares
                           to Schering, by paying cash to Schering, or some
                           combination thereof in the sole discretion of
                           Techniclone, but in any event such payment shall be
                           made to Schering within ten trading days from the
                           date of written notification from Schering to
                           Techniclone of the shortfall. The Parties recognize
                           that if Techniclone makes up any shortfall through
                           the transfer of additional Payment Shares to
                           Schering, then the process described above may have
                           to be repeated more than once in order for Schering
                           to realize Proceeds equal to one million, three
                           hundred thousand United States dollars ($1,300,000).
                           Schering agrees to provide Techniclone with a copy of
                           the relevant broker/dealer trading record within a
                           reasonable time of receipt of a written request from
                           Techniclone. Schering's obligations under this
                           Amendment and the Agreement are conditioned upon
                           Schering realizing Proceeds equal to one million,
                           three hundred thousand United States dollars
                           ($1,300,000) (with any shortfall to be made up in
                           Payment Shares, cash, or a combination thereof by
                           Techniclone as described above), and Schering shall
                           have no obligation to perform under this Amendment or
                           the Agreement until such time as such sum is realized
                           by Schering. In the event that Schering realizes more
                           that one million, three hundred thousand United
                           States dollars ($1,300,000), Schering shall refund
                           such excess to Techniclone.

                                    (ii) Schering agrees not to sell more than
                           that number of Payment Shares on any trading day that
                           exceeds ten percent (10%) of the trading volume of
                           Techniclone shares on that day.

                                    (iii) Techniclone agrees to use its best
                           efforts to file an S-3 registration statement with
                           the United States Securities and Exchange Commission
                           within seven (7) days of the Effective Amendment Date
                           providing for the registration of the Payment Shares,
                           and to have an effective registration statement
                           within forty-five (45) days of the Effective
                           Amendment Date.

                                       4
<PAGE>

                           (B) FROM DECISION POINT #1 THROUGH DECISION POINT #2.

                                    (i) In the event that Schering determines to
                           go forward with Clinical Development after Decision
                           Point #1 as provided herein, Schering shall so notify
                           Techniclone in writing. In consideration of
                           Schering's agreement to undertake responsibility for
                           payment of Clinical Development Expenses from
                           Decision Point #1 through Decision Point #2, as
                           described above, Techniclone agrees to transfer to
                           Schering, within three (3) days after the
                           registration statement described below in Section
                           3.04(d)(B)(iii) becomes effective, Payment Shares
                           equal to one million, seven hundred thousand United
                           States dollars ($1,700,000) determined by the average
                           closing stock price for the five trading days prior
                           to the date the registration statement becomes
                           effective. In addition, in lieu of transferring all
                           or part of the Payment Shares to Schering,
                           Techniclone shall have the right to pay Schering in
                           cash at any time to satisfy the obligations of
                           Techniclone hereunder, for either the full amount due
                           to Schering or any portion thereof, at the sole
                           discretion of Techniclone. The Parties recognize that
                           the public market for securities in the United States
                           is volatile, and that as a result Schering may not
                           realize Proceeds of one million, seven hundred
                           thousand United States dollars ($1,700,000) (or such
                           lower amount as may be applicable if Techniclone has
                           satisfied part of its obligations hereunder in cash)
                           when it sells the Payment Shares. In the event that
                           Schering realizes Proceeds of less than one million,
                           seven hundred thousand United States dollars
                           ($1,700,000) (or such lower amount as may be
                           applicable if Techniclone has satisfied part of its
                           obligations hereunder in cash) as a result of the
                           sale of the Payment Shares, Schering shall notify
                           Techniclone of the shortfall. Techniclone shall pay
                           the amount of the shortfall to Schering either by
                           issuing additional Payment Shares to Schering, by
                           paying cash to Schering, or some combination thereof
                           in the sole discretion of Techniclone, but in any
                           event such payment shall be made to Schering within
                           ten trading days from the date of written
                           notification from Schering to Techniclone of the
                           shortfall. The Parties recognize that if Techniclone
                           makes up any shortfall through the transfer of
                           additional Payment Shares to Schering, then the
                           process described above may have to be repeated more
                           than once in order for Schering to realize Proceeds
                           equal to one million, seven hundred thousand United
                           States dollars ($1,700,000). Schering agrees to
                           provide Techniclone with a copy of the relevant
                           broker/dealer trading record within a reasonable time
                           of receipt of a written request from Techniclone.

                                       5
<PAGE>

                           Schering's obligations under this Amendment and the
                           Agreement following Decision Point #1 are conditioned
                           upon Schering realizing Proceeds equal to one
                           million, seven hundred thousand United States dollars
                           ($1,700,000) (with any shortfall to be made up in
                           Payment Shares, cash, or a combination thereof by
                           Techniclone as described above), and Schering shall
                           have no obligation to perform following Decision
                           Point #1 under this Amendment or the Agreement until
                           such time as such sum is realized by Schering. In the
                           event that Schering realizes more that one million
                           United States dollars ($1,700,000), Schering shall
                           refund such excess to Techniclone.

                                    (ii) Schering agrees not to sell more than
                           that number of Payment Shares on any trading day that
                           exceeds ten percent (10%) of the trading volume of
                           Techniclone shares on that day.

                                    (iii) Techniclone agrees to use its best
                           efforts to file an S-3 registration statement with
                           the United States Securities and Exchange Commission
                           within seven (7) days of receipt by Techniclone of
                           the written notice from Schering stating that
                           Schering has determined to go forward with Clinical
                           Development following Decision Point #1 providing for
                           the registration of the Payment Shares, and to have
                           an effective registration statement within forty-five
                           (45) days of such written notice from Schering.

                           (C) CREDIT FOR CLINICAL DEVELOPMENT EXPENSES
                           FOLLOWING DECISION POINT #2. In the event that
                           Schering determines to go forward with Clinical
                           Development after Decision Point #2, then eighty
                           percent (80%) of the Proceeds of the Payment Shares
                           actually spent by Schering on Clinical Development
                           Expenses from the Effective Amendment Date through
                           Decision Point #2 shall be credited toward
                           Techniclone's obligations under Section 3.04(b)
                           incurred after Decision Point #2.

SECTION 4: AMENDMENT OF SECTION 12.02(a); ADDITION OF SECTION 12.02(J). The
Parties agree to delete clauses (A), (B), (C) and (D) from Section 12.02(a)(ii),
to delete Section 12.02(a)(v) from the Agreement and to replace it with the
following new Section 12.02(a)(v), to add new Sections 12.02(a)(viii) and
12.02(a)(ix), and to add a new Section 12.02(j) to the Agreement, as follows:

                                    (v) upon thirty days' written notice given
                           at any time subsequent to Decision Point #2 and prior
                           to Regulatory Approval for any reason;

                                       6
<PAGE>

                                    (viii) upon thirty days' written notice in
                           the event that Schering determines that it is not
                           commercially reasonable to continue Clinical
                           Development. Schering acknowledges that there are
                           several competitive products for Non-Hodgkins
                           Lymphoma currently under development. These products
                           include but are not limited to products under
                           development at Coulter, Idec, SmithKline Beecham,
                           Genentech, Immunomedics, and NeoRx. Schering agrees
                           that the public release of efficacy data after the
                           Effective Amendment Date for any other product for
                           Non-Hodgkins Lymphoma, or the regulatory approval in
                           any country for any such product shall not constitute
                           a reason for termination under this Subsection prior
                           to the Decision Point.

                                    (ix) upon thirty days' written notice if, at
                           Decision Point #1, Schering determines that the
                           clinical efficacy of the Product does not warrant
                           further clinical development.



                  (j) REFUND OF CERTAIN SUMS TO TECHNICLONE. In the event that
this Agreement is terminated in its entirety by Schering under any provision of
Section 12.02, other than a termination by Schering on account of Techniclone's
failure to comply with one or more of Techniclone's material obligations
pursuant to Section 12.02 (b), then Schering shall refund to Techniclone any
Proceeds realized by Schering pursuant to Section 3.04(d) in excess of
Schering's actual Clinical Development Expenses incurred prior to the date of
termination. Schering shall have the right to deduct from the amount to be
refunded pursuant to this Section 12.02(j) any sums then owed to Schering by
Techniclone, whether or not such sums are related to Clinical Development
Expenses.

SECTION 5: PRESS RELEASE. Schering agrees that within ten (10) business days of
the commencement to the first clinical trial contemplated by this Amendment, it
will publish a press release reasonably satisfactory to both Schering and
Techniclone referring to such clinical trial, expressing in reasonable business
terms Schering's support of the Clinical Development of Oncolym and Schering's
desire to continue to work with Techniclone in such Clinical Development.

SECTION 6: EFFECT OF AMENDMENT. This Amendment is intended to supplement and
modify the terms of the Agreement, it being the intent of the Parties that this
Amendment shall control the construction, interpretation, and intent of the
Agreement. This Amendment shall be effective as of the Effective Amendment Date.
From and after the Effective Amendment Date all references in and to the

                                       7
<PAGE>

Agreement shall be deemed to include this Amendment. This Amendment is limited
as specified, and shall not constitute an amendment, modification, or waiver of
any other provisions of the Agreement. This Amendment shall be subject to
Section 14.09 of the Agreement. This Amendment may be executed in two or more
counterparts, each of which shall be deemed to be an original, but all of which
taken together shall constitute one and the same instrument.

SECTION 7: EXECUTION BY COUNTERPARTS; EXCHANGE BY FACSIMILE. This Amendment may
be executed by the Parties in one or more counterparts. Such counterparts may be
exchanged by facsimile (provided that each executed counterpart is transmitted
in one complete transmission). Where there is an exchange of executed
counterparts, each Party shall be bound by the Agreement as amended by this
Amendment notwithstanding that original copies of the Amendment may not be
exchanged immediately. The Parties shall cooperate after execution of the
Amendment and exchange by facsimile to ensure that each Party obtains an
original executed copy of this Amendment.



(Remainder of page intentionally left blank.)

                                       8
<PAGE>


IN WITNESS WHEREOF, the Parties have executed this Amendment as of the Effective
Amendment Date.





TECHNICLONE CORPORATION                     SCHERING AG



By: /S/ JOHN  N. BONFIGLIO                  By: /S/ G. STOCK
     -------------------------                  --------------------------------
        John Bonfiglio, Ph. D.,                 Prof. G. Stock,
        President & CEO                         Member of Executive Board of
                                                Directors



                                            By: /S/ J.F. KAPP
                                                --------------------------------
                                                Dr. J.-F. Kapp,
                                                Head of Strategic Business Unit,
                                                Therapeutics


                                       9